The rules set out in GOST 21.205–93, regulate exactly how alphanumeric characters should be applied on the drawings pipeline designations plumbing systems that relate to external networks of heat supply, sewerage and water supply, as well as to internal water and sewer networks, heating networks, ventilation and air conditioning systems.

Alphanumeric designation	Name
Water pipes
B0	General designation of the water supply
IN 1	Domestic and drinking water supply
IN 2	Fire water supply
Industrial plumbing
AT 3	General designation of industrial water supply
AT 4	Plumbing of circulating water supply
AT 5	Circulating water pipeline, return
AT 6	Soft water plumbing
AT 7	For river water
AT 8	For river clarified water
AT 9	For underground water
Sewerage
K0	General designation of the sewer
K1	domestic sewerage
K2	Rain sewer
industrial sewerage
K3	General designation of industrial sewage
K4	Sewerage for mechanically polluted waters
K5	sludge sewerage
K6	Sewage for sludge-containing waters
K7	For chemically polluted waters
K8	Sewerage for acidic waters
K9	For alkaline waters
K10	For acidic waters
K11	For cyanide waters
K12	For chromium-containing waters
Heat pipe
T0	General designation of the pipeline
For heating, ventilation, air conditioning and technical processes
T1	Supply pipeline
T2	Return pipeline
Pipeline for hot water supply
T3	Server
T4	circulation
Hot water for technological processes
T5	Supply pipeline
T6	Return pipeline
Steam heating
T7	Steam pipeline
T8	Condensate line

Note:

For those pipeline systems of sewerage and water supply that are not provided for in the table, designations must be adopted by establishing a serial numbering that is a continuation of the one indicated in the table.

If an industrial or domestic drinking water supply system simultaneously performs the role of a fire-fighting one, then it is assigned exactly the same number as the industrial or domestic drinking water supply. At the same time, an appropriate explanation is applied to the drawing.

Pipeline

In modern technology, pipelines are such devices that are designed to transport a variety of liquid, gaseous and granular media. The main components of pipeline systems are: straight pipes that are tightly interconnected; hangers and supports; control and measuring equipment; shut-off and control devices; fasteners; seals and gaskets; means of automation.

In addition, the elements of pipeline systems include the materials necessary to ensure effective protection of all the above components from the harmful effects of low and high temperatures, as well as from electrochemical corrosion.

The locations of the elements of pipeline systems are their branches, turns, as well as transitions to a different diameter. They serve to ensure a long service life of the system as a whole, as well as the tightness of the entire structure. Practice shows that almost no pipeline system is implemented without such elements as bends, tees and transitions.

Liquid Properties

Liquids are those substances that are in a liquid state of aggregation. It, in turn, is intermediate between the aggregate state of solid and gaseous. The liquid also has a property that is not found in any other state of aggregation: it is capable of changing its shape under the influence of tangential mechanical stresses within practically unlimited limits. In this case, mechanical stresses can be very small, and the volume of the liquid remains unchanged.

Another important property inherent in all liquids is surface tension. Neither gases nor solids have it, but it is explained by the following reasons: due to the fact that the balance of the forces acting on the molecules of the surface is disturbed, a certain new resultant force directed inside the substance appears. This explains the fact that the surface of a liquid is always "stretched". If we consider this situation from the point of view of physics, then it can be argued that surface tension is nothing but the force due to which the molecules of a liquid do not move from its surface to the deep layers. It is the force of surface tension that explains the shape of falling drops of any liquid.

USSR STATE STANDARD

GOST 14202-69 USSR STATE COMMITTEE ON STANDARDS MOSCOW

USSR STATE STANDARD

By the Decree of the Committee of Standards, Measures and Measuring Instruments under the Council of Ministers of the USSR dated February 7, 1969 No. 168, the introduction period was established

1. This standard applies to identification coloring, warning signs and marking plates of pipelines (including fittings, fittings, fittings and insulation) for designed, newly built, reconstructed and existing industrial enterprises inside buildings, for outdoor installations and communications located on overpasses and in underground channels in order to quickly determine the contents of pipelines and facilitate the management of production processes, as well as ensuring labor safety.

The standard does not apply to the identification coloring of pipelines and ducts with electrical wiring.

2. The following ten enlarged groups of substances transported through pipelines are established:

3) air;

4) combustible gases (including liquefied gases);

5) non-flammable gases (including liquefied gases);

6) acids;

7) alkalis;

8) combustible liquids;

9) non-flammable liquids;

10) other substances.

3. Identification coloring and digital designation of enlarged groups of pipelines must correspond to those indicated in the table

1. 4. The characteristics of the colors of the identification color must correspond to those specified in the application

1. 5. Fire-fighting pipelines, regardless of their contents (water, foam, steam for extinguishing a fire, etc.), sprinkler and deluge systems in the areas of shut-off and control valves and at the points of connection of hoses and other fire extinguishing devices must be painted in red color (signal).

If it is necessary to indicate the contents of fire-fighting pipelines, it is allowed to additionally designate them by means of marking plates painted in the appropriate distinctive colors.

Table 1

Substance being transported		Samples and name of colors of identification coloring
Group number	Name
1	Water	Green
2	Steam	Red
3	Air	Blue
4	combustible gases	Yellow
5	Non-flammable gases	Yellow
6	acids	Orange
7	alkalis	Violet
8	Flammable liquids	Brown
9	Non-flammable liquids	Brown
9	Other substances	Grey

6. Identification painting of pipelines should be carried out continuously over the entire surface of communications or in separate sections.

The method for performing identification painting should be selected depending on the location of the pipelines, their length, diameter, the number of lines located together, safety and industrial sanitation requirements, lighting conditions and visibility of pipelines for maintenance personnel and the general architectural solution.

It is recommended to paint pipelines in sections in workshops with a large number and length of communications, as well as in cases where, due to the increased requirements for color rendering and the nature of the architectural solution of the interior, a concentration of bright colors is undesirable due to working conditions.

Identification painting over the entire surface of pipelines is recommended for use with a small length and a relatively small number of communications, if it does not worsen working conditions in the shops.

On outdoor installations, it is recommended to use identification coloring over the entire surface only in cases where this does not cause deterioration of operating conditions due to the effect of solar radiation on communications.

7. When applying identification coloring in sections to pipelines located inside industrial premises, it is recommended to paint the rest of the communication surface in the color of walls, partitions, ceilings and other interior elements against which the pipelines are located. At the same time, it is not allowed to paint pipelines between sections with an identification color adopted to designate other enlarged groups of substances.

8. When applying identification coloring in sections to pipelines located outside buildings, it is recommended to paint the rest of the communications surface in colors that help reduce the thermal effect of solar radiation on pipelines.

9. When laying communications in impassable channels and when laying communications without channels, areas of identification coloring on pipelines should be applied within the chambers and manholes.

10. Areas of identification coloring should be applied taking into account local conditions at the most critical communication points (at branches, at joints, flanges, at sampling and instrumentation points, at places where pipelines pass through walls, partitions, ceilings, at inputs and outputs from industrial buildings etc.) at least every 10 m inside production facilities and outdoor installations and every 30-60 m on external main routes.

11. The width of the areas of identification coloring should be taken depending on the outer diameter of the pipelines (including insulation):

• for pipes with a diameter of up to 300 mm - at least four diameters;
• for pipes with a diameter of more than 300 mm - at least two diameters.

With a larger number of parallel communications, it is recommended that the areas of identification coloration on all pipelines be of the same width and applied at the same intervals.

With large diameters of pipelines, areas of identification coloring may be applied in the form of strips, with a height of at least 1/4 of the circumference of the pipeline.

The width of the strips must correspond to the dimensions established for pipelines of a given diameter.

12. To designate the most hazardous substances transported by properties, warning color rings should be applied to pipelines.

The colors of the identification color for warning rings must correspond to those indicated in Table. 2.

13. In cases where a substance simultaneously has several dangerous properties, indicated by different colors, rings of several colors should be applied to pipelines at the same time.

On vacuum pipelines, in addition to the distinctive color, it is necessary to give the inscription "vacuum".

14. According to the degree of danger to human life and health or the operation of the enterprise, substances transported through pipelines should be divided into three groups, indicated by the corresponding number of warning rings in accordance with table 3.

15. Characteristics of signal colors must comply with those specified in Appendix 2.

16. The width of the warning rings and the distance between them must be taken depending on the outer diameter of the pipelines in accordance with drawing. 1 and tables 4.

17. With a large number of parallel communications, warning rings on all pipelines should be of the same width and applied at the same intervals.

table 2

Notes:

1. When applying yellow rings for identification coloring of pipelines of gases and acids, the rings must have black borders with a width of at least 10 mm.

2. When applying green rings for the identification color of water pipelines, the rings must have white borders with a width of at least 10 mm.

18. Gas outlet lines and venting to the atmosphere, depending on their contents, must have an identification color established for the symbolic designation of enlarged groups, with winding transverse rings of the corresponding signal color.

19. To designate pipelines with content that is especially hazardous to human health and life or the operation of an enterprise, as well as, if necessary, to specify the type of hazard, warning signs should be used in addition to color warning rings.

20. Warning signs should indicate the following substances: poisonous, flammable, explosive, radioactive, as well as other dangerous contents of pipelines (for example, substances that are hazardous when splashed, etc.).

21. Warning signs should be in the form of a triangle. Images must be black on a yellow background.

Table 3

Group	Number of warning rings	Substance being transported	Pressure in kgf/cm2	Temperature in °C
1	One	superheated steam	up to 22	250 to 350
		Hot water, saturated steam	16 to 80	St. 120
		Superheated and saturated steam, hot water	1 to 16	120 to 250
		Combustible (including liquefied and active gases, flammable and combustible liquids)	up to 25	From minus 70 to 250
			Up to 64	From minus 70 to 350
2	Two	superheated steam	Up to 39	350 to 450
		Hot water, saturated steam	80 to 184	St. 120
		Products with toxic properties (except for highly active toxic substances and fuming acids)	Up to 16	From minus 70 to 350
		Combustible (including liquefied) active gases, flammable and combustible liquids	25 to 64	250 to 350 and minus 70 to 0
		Non-flammable liquids and lares, inert gases	64 to 100	From 340 to 450 and from minus 70 to 0
3	Three	superheated steam	Regardless of the pressure	450 to 660
		Hot water, saturated steam	St. 184	St. 120
		Potent toxic substances (SDN) and fuming acids	Regardless of the pressure	From minus 70 to 700
		Other products with toxic properties	St. 16	From minus 70 to 700
		Combustible (including liquefied) and active gases, flammable and combustible liquids	Regardless of the pressure	350 to 700
		Non-flammable liquids and vapors, inert gases	Regardless of the pressure	450 to 700

Note. For substances that are hazardous in terms of properties or a combination of properties that are not included in this table, hazard groups should be established in agreement with the Gosgortekhnadzor authorities.

Table 4

22. The image of warning signs should be taken in accordance with Drawing 2 and Table 5

Toxic substances	Flammable substances	radioactive substances	Explosives
Caustic and corrosive substances	Harmful and allergic substances	Oxidizer	Other hazards

Table 5

Options	a, mm
1	56
2	52
3	74
4	105
5	148

23. In cases where the impact of aggressive flowing substances can cause a change in the hue of distinctive colors, pipelines should be marked with marking plates.

24. Labeling plates should be used to additionally indicate the type of substances and their parameters (temperature, pressure, etc.) required by the operating conditions. Marking plates on pipelines or on the surfaces of structures to which pipelines are attached must be marked with alphabetic or numeric inscriptions.

25. The inscriptions on the shields of the pipelines must be made in a clear, well-defined font and must not contain unnecessary data, little-used terms and incomprehensible abbreviations. The font for inscriptions is recommended to be taken in accordance with GOST 10807-78.

It is allowed to designate the type of substance by means of numbers in accordance with Appendix 3. The designation of the type of substance by means of chemical formulas is not allowed.

26. The direction of the flow of substances transported through pipelines should be indicated by the sharp end of the marking plates or arrows applied directly to the pipelines. The shape and size of the arrows must match the shape and size of the labels.

27. Marking shields must be of four types: 1 - to indicate the flow moving in both directions; 2 the same, in the left direction; 3 the same, in the right direction; 4 - to indicate the place of selection of the transported substance.

28. The dimensions of the camouflage shields must correspond to those indicated in Fig. 3 and in table. 6.

Table 6

Size options	a, mm	b, mm	Height of letters h, mm
			one line	two lines
1	26	74	19	-
2	52	148	32	19
3	74	210	50	25
4	105	297	63	32
5	148	420	90	50

29. Size options for labels, inscriptions and warning signs should be used mainly:

• 1-in laboratories;
• 2 and 3 - in industrial premises;
• 4 and 5 - on outdoor installations and outdoor trunk routes.

30. When attaching them to pipelines, warning signs should be placed together with marking plates.

31. The height of markings on pipelines should be taken depending on the outer diameter of the pipeline in accordance with drawing. 4 and table. 7.

Table 7

Size options	Outer diameter D, mm	Height of letters h, mm
		one line	two lines
1	up to 30	19	-
2	81 to 160	32	19
3	161 to 220	50	25
4	221 to 300	63	32
5	St. 300	90	50

The color of markings and arrows indicating the direction of flow applied to pipelines and marking plates should be white or black, taking into account the greatest contrast with the main color of the pipelines.

The color of the inscriptions when applied against the background of identification coloring is taken:

• white-on green, red and brown background;
• black on blue, yellow, orange,
• purple and gray background.

32. The size of labels, inscriptions and warning signs should be selected depending on the distance from which they should be perceived by personnel associated with the operation of pipelines in accordance with drawing. 5 and tab. eight.

33. Paint and varnish coatings for identification painting, marking plates and warning signs must be carried out in accordance with the current standards for paintwork materials and coatings, depending on the material of pipelines or the insulation protecting them and operating conditions, as well as the cost of paint and varnish coatings and the technology of their application.

34. Paints and varnishes used for identification painting, marking plates and warning signs must meet the requirements of the relevant standards, as well as technical documentation approved in the prescribed manner.

35. When preparing surfaces for painting, applying and drying paint and varnish coatings, the safety regulations and fire prevention measures provided for by the current fire regulations and rules must be observed.

36. In heated and ventilated industrial premises without aggressive environments, it is recommended to carry out the identification coloring of pipelines, marking plates and warning signs with pentaphthalic enamels of grades PF-115 according to GOST 6465-76, PF-133 according to GOST 926-82 and other brands according to the technical documentation approved according to established order.

It is recommended to paint fire-fighting pipelines and equipment with red enamel according to the technical documentation approved in the prescribed manner.

37. Identification colors and signal colors are allowed to be accepted in accordance with the following standards of the color standard card index:

• green #343-344;
• red #10-11;
• blue #423-424;
• yellow #205-206;
• orange #101-102;
• purple #505-506;
• brown #647-648;
• gray #894-895.

Required shades of purple and brown in accordance with the samples of Table. 1 can be obtained by adding white paint.

38. The identification coloring of pipelines and the color finish of marking plates and warning signs should be periodically renewed, taking into account the provision of clear visibility of colors, images and inscriptions. The coloring should be even, without streaks, wrinkles, spots and should not peel off.

39. Marking boards, inscriptions and warning signs should be located taking into account local conditions at the most critical communication points (at branches, at junctions, at points of selection, at valves, gate valves, valves, gates, control devices, at places where pipelines pass through walls , partitions, ceilings, at inputs and outputs from industrial buildings, etc.). Marking plates, warning signs and inscriptions on pipelines should be located in well-lit places or illuminated to ensure their clear visibility, while light sources should not obscure the images and inscriptions, as well as dazzle personnel when observing them.

Table 8

It is recommended to take the lowest illumination at critical points of communication when labeling plates, inscriptions and warning signs are located in them at 150 lux with fluorescent lamps and 50 lux with incandescent lamps.

40. In all industrial premises where there are pipelines, in places that are well accessible for viewing, identification coloring schemes for communications should be hung out with a decoding of the distinctive colors, warning signs and digital designations adopted for marking pipelines.

X>0.526-0.683y

x<0,410-0,317у

y>0.282+0.396x

at<0,547-0,394x

Below are answers to the most common questions about marking pipelines for industrial and civil facilities.

What color should the pipelines be painted in the central heating station, ITP, boiler room?

According to GOST 14202, the marking of pipelines does not depend on the object, but depends on the substance in the pipeline.

Pipelines with the transported substance WATER are painted green, STEAM - red, AIR - blue, GAS - yellow, ACIDS - orange, ALKALINE - violet, LIQUIDS - brown, OTHER - gray.

How to mark pipelines in the central heating station, ITP, boiler room?

The most common substances in the pipelines of the central heating substation/ITP/boiler rooms are water, steam, and gas.

The pipeline with water should be painted green, with steam - red, with gas - yellow. Identification coloring is allowed to be applied in sections.

It is also necessary to indicate the name and direction of movement of the substance using or. Their color must be the same as that of the identification markings. The locations of the shields are regulated by regulatory documentation.

What color should the hot/cold water/coolant pipes be painted?

All pipelines transporting substances, the main component of which is water, are painted green in accordance with.

How, according to regulatory documentation, to distinguish the color of the supply pipeline from the return pipeline in the central heating station, ITP, boiler room?

If the pipelines are marked in accordance with, then the supply and return pipelines are painted green (if the heat carrier is water).

To identify the supply and return pipelines, use the appropriate designations with the direction of movement and the inscription, for example “HEATING TRANSPORT SUPPLY”

Is it correct to mark the coolant supply / return pipelines with yellow and brown rings on a green background?

The requirement to mark the supply pipeline of the heating network with a yellow ring on a green background, and the return pipeline - with a brown ring on a green background, is borrowed from the now inactive "Typical instructions for the operation, repair and control of stationary pipelines of network water RD 34.39.501, TI 34-70-042- 85" and was valid only for network water pipelines that are on the balance sheet of power plants.

The current regulatory documentation for marking pipelines with coolant refers exclusively to the requirements of GOST 14202.

How to mark gas pipelines correctly?

Pipelines transporting any gases are painted yellow in accordance with.

You must specify the name of the gas and the direction of movement using or.

It is also necessary, depending on the parameters of the gas, to apply warning rings of red or yellow color (table 3), and if the gas has a dangerous property (flammability, toxicity, oxidizing agent), then it is necessary to apply the appropriate hazard sign.

How to mark steam pipelines?

Steam pipelines must be painted red and a red shield with the name and direction of its movement must be applied.

If the pressure in the steam pipeline is more than 1 kgf / cm² and the temperature of St. 120C, a yellow warning ring must be applied over the paint. With an increase in steam parameters, the number of applied rings increases (see Table 3

GOST 14202-69 has the status of a valid document.

What materials should be used when marking pipelines in accordance with GOST 14202-69?

There are also no documents prohibiting marking with self-adhesive tapes and PVC-based markers.

Moreover, the use of self-adhesive materials is more expedient (generally accepted all over the world) - more convenient, faster, more accurate, allows you to more accurately comply with the important requirements of GOST for color, size, font and shape.

Crimping is not just a hydraulic test of the system. This is a whole series of measures aimed at preparing the system for the heating season. This includes the repair of emergency sections, the replacement (repair) of valves, and the verification of pressure gauges, cleaning filters and much more.

In this article I will describe the main points that representatives of regulatory authorities pay attention to. The following is not the ultimate truth, each inspector has his own cockroaches in his head. But the necessary minimum of work must be done in any case.

So let's go...

First, let's figure out what we will crimp. There are several options for connecting the building to the heating network. The first, most common option is when introductory valves are installed near the wall at the entrance from the city. With this option, the boundary of the division of responsibility is the flange of the inlet valve, for everything further (including the inlet valve), the owner of the building is responsible. Accordingly, the heating unit and the heating system of the building are pressed.

The second option is when the heating unit is located inside the building, and an internal heating main runs through the building from the inlet valves to it. With this connection option, you need to specify where the demarcation line passes. The “Heat Supply Agreement”, which is concluded between the owner and the heat supply company, will help us with this. This agreement has an appendix, which indicates where the demarcation line passes.

If the inlet valves are considered to be the demarcation boundary, we press three elements of the system: the internal heating main, the heating unit and the heating system. If the delineation of responsibility passes through the valves at the heating unit, naturally, we only pressure test the elevator (heat) unit and the heating system.

Pressure gauges

Perhaps the first thing the inspector turns his attention to when accepting a pressure test is pressure gauges.

Checking the pressure gauge

The pressure gauges must be checked every year. Verification is a check of the measuring device for the accuracy of the readings. If the pressure gauge readings exceed the allowable error, it must be sent for calibration or replaced. Calibration, in fact, is the adjustment of the pressure gauge, aimed at reducing the error in the accuracy of measurements.

After verification, the stamp of the Metrological Service is applied to the pressure gauge body.

1. Month of the year (1, 2, 3, etc.), quarter (I, II, III, IV).
2. Sign of the State Standard.
3. The last digits of the year (here 2002).
4. Individual sign of the believer.
5. Code of the Metrological Service.

New pressure gauges are subject to verification only after 18 months, that is, one year after commissioning. But when checking, you must provide passports for these devices (they are included).

Pressure gauge connection

The pressure gauge must only be connected to a three-way valve or a ball valve with a pressure relief valve. Ordinary ball valves do not work.

Three-way faucets often leak. Tip: to avoid leakage, rotate the valve stem several times around its axis before installation. Thus, you will evenly lubricate the stem and the inner surface of the valve with grease, which was applied during assembly.

Where should the gauges be?

Regarding the installation site of pressure gauges, there is a whole bunch of standards (DBN V.2.5-39 -, SNiP 2.04.01 - Internal water supply and sewerage of buildings, SNiP 2.04.05 Heating, ventilation and air conditioning, SNiP II-35 Boiler installations). In simple words, I will say this: pressure gauges should be placed before and after any equipment that can affect the change in pressure: on all outgoing and passing pipelines before and after shutoff valves, before and after control equipment, before and after mud collectors (to control its condition) and etc.

Another nuance that the inspector can pay attention to is the pressure gauge rating. In heat points, pressure gauges with a nominal value of up to 1.6 MPa (16 bar) should be installed.

thermometers

The sleeve (pocket) of the thermometer should go 2/3 into the pipeline, so that the immersed part is in the center of the flow.

Shown here is a wrong gauge connection.

To ensure good thermal contact, the thermometer sleeve must be filled with mineral oil (GOST 8.586.5-2005 p.6.3.9.).

Washing of filters and mud collectors

Cleaning filters and mud collectors is a mandatory procedure in the process of preparing heating for the heating season. The process of flushing the sump is quite simple: the flange is untwisted, and all the dirt is cleaned out of the sump. The same goes for the oblique filter.

Elevator

The main requirement for the elevator assembly is the flushing of the cone (nozzle). The diameter of the hole in the cone is 5-7 mm (calculated individually for each building), if the cone clogs, the building will not receive the required amount of heat.

The elevator must be sealed. To flush the nozzle, the seal must be removed, but in order to avoid unnecessary questions, this must first be agreed with the inspector who will take the pressure test from you. After washing, the elevator is sealed again.

Often, inspectors require that a tag hang on the elevator with the diameter of the hole in the cone indicated on it.

Insulation and warning color rings on pipelines

All pipelines in the ITP (CTP) must be painted and insulated. Insulation should not hang in tatters, everything should be neat. Accounting units and elevators are also isolated.

The direction of movement of the coolant should be indicated on the pipeline with markers. To identify the contents of the pipes, warning colored rings are applied to them. For heating, green (main color) and yellow rings are used on the supply, green and brown on the return. The same marking is used for DHW. Drainage and cold water are indicated by green rings.

Shut-off valves

Shut-off valves must perform their main function - to block the flow of coolant. If there are valves on the thermal unit that “do not hold”, they must be replaced. Different parts of the system are pressure tested under different pressures, and if there is a non-working valve in the circuit, it will definitely show itself.

Reinforcement marking

Ideally, everything should look like this: the heating point should have a diagram showing numbered and marked inlet and outlet pipelines, shut-off and control valves, drain and drainage devices. The scheme must correspond to the current state of the system, that is, if changes have been made to the system, they must be displayed on the diagram.

All of the above devices must have tags with symbols corresponding to the symbols in the diagram (1,2 - shutoff valves on the supply and discharge pipelines, t1 and t2 - thermometers, P1 and P2 - pressure gauges, etc.).

In practice, in small heating points, inspectors do not always focus on this. The main thing is to make it clear what goes where, for example: “supply to the left wing”, “return from the right wing”, “supply to ventilation”, etc. But if everything is "feng shui" - this is an additional plus.

Revision of gate valves

Old-style wedge gate valves require additional attention during operation.

Wedge valve device: 1 - wedge, 2 - cover, 3 - handwheel, 4 - seat, 5 - body, 6 - sealing ring, 7 - spindle, 8 - threaded bushing, 9 - bushing, 10 - stand, 11 - stuffing box flange , 12 - gland seal made of thermally expanded graphite.

In such valves, it is mandatory to carry out stuffing of the stuffing box every year. And during the year, in the event of a leak from the stuffing box, it is necessary to tighten the flange. If this is not done, the valve will become unusable.

To replace the gland packing, unscrew the nuts on the cap bolts, lift the flange, remove the old gland packing and fill in a new one. The seal is wound in rings around the spindle and pressed against the flange.

When tightening the flange, you need to be careful: if you overdo it, the cast-iron flange can burst, and its replacement is very problematic, in practice it is easier to change the valve completely.

The valve must show no signs of rust. The body must be painted black, the flywheel red, and the retractable spindle must be lubricated with grease.

Drainage

Heating points are equipped with a drain for gravity water drainage, and if it is impossible to implement, a drainage pit with a pump (SP 124.13330.2012 Heat networks. Updated edition of SNiP 41-02-2003 p. 14.20). The pit is closed with a removable grate. The latest innovation is that the edge of the pit should be painted with yellow and black stripes.

If there is a safety valve in the TP, then it must be equipped with a drainage pipeline so that no one (or nothing) is injured in the event of a drawdown.

Outcome

There were cases when the inspector said in plain text that he would find ten comments on two meters of the heating unit. It doesn't matter that last year there were no such remarks. In the eyes of the regulatory authorities, an ideal system does not exist. But that's a topic for another conversation...

Marking of pipelines, in accordance with current standards, is carried out to identify the substance transported in it. Usually, the recognition of substances is carried out using color analyzers. Special identification rings, stickers with warning inscriptions can also be applied (this applies to hazardous substances).

Modern marking of pipelines, etc. is done only in accordance with GOST. The surface of the pipeline is painted in a certain color, special inscriptions are attached. Heat exchangers, as well as pipelines through which hot water or steam is supplied, are painted with heat-resistant enamel. It is necessary that all inscriptions exactly comply with the rules for the safe operation of steam and hot water. On the main lines, a number must be applied in Roman numerals, as well as an arrow showing the direction of movement of the transported substance. The same trunk number is applied to trunk branches. All inscriptions must be clearly visible, they must not be obscured by valves and gate valves.

According to GOST 14202 69, if the surface of the pipeline is covered with metal sheathing, the coloring of this sheathing is optional, but a symbol of its type and class of the transported substance can be applied to the pipeline. The coloring and inscriptions on these pipelines must strictly comply with the same standard.

All equipment carrying hot liquid or steam must be adequately insulated. This is done to avoid burns. The temperature at the surface of the insulation must not cause damage to the skin when touched.

The pipelines must have arrows showing the movement of the working fluid. All inscriptions must be visible and printed only. Highly visible serial numbers should also be applied to pumping units, valves, gates and other mechanisms. Also, pipes need appropriate markings, which should indicate their purpose. In this case, it can be easily identified.

All state standards are obligatory for observance by all subjects of housing and communal services, heat supply, regardless of their form of ownership. Failure to comply with such rules can lead to accidents, fires and other man-made incidents.

Reliable and simple reducer Ch-80
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Currently, manual rollers are used for single-piece production of bulk products, and modern equipment equipped with automation is more suitable for large-scale production. In addition to bending flat sheet and metal profiles, the production of products requires metal cutting, and now such operations are carried out using high-precision equipment.

STP OmGUPS–1.13–04

Enterprise Standard

Approved and put into effect by order No.

Date of introduction 01.06.04

1 area of ​​use

This standard establishes rules for the design of thermal circuits.

The requirements of the standard apply to student educational and final qualification papers performed at all departments of the university.

2 Normative references

GOST 2.780-96. ESKD. Conditional graphic designations. Working environment conditioners, hydraulic and pneumatic tanks;

GOST 2.781-96. Eskd. Conditional graphic designations. Hydraulic and pneumatic devices, control devices and instrumentation;

GOST 2.782–96. ESKD. Conditional graphic designations. Pumps and motors hydraulic and pneumatic;

GOST 2.784–96. ESKD. Conditional graphic designations. Elements of pipelines;

GOST 21.205–93. SPDS. Symbols for sanitary systems;

GOST 21.206–93. SPDS. Symbols of pipelines;

GOST 21.403–80. SPDS. Conditional graphic designations in schemes. Energy equipment;

GOST 21.404–85. SPDS. Automation of thermal processes. Conventional designations of devices and automation equipment in diagrams;

GOST 21.604–82. SPDS. Water supply and sewerage. External networks;

GOST 21.605–82. SPDS. Thermal networks. Working drawings;

GOST 21.606-95. SPDS. Rules for the implementation of working documentation for thermal mechanical solutions of boiler rooms;

GOST 21.609–83. SPDS. Gas supply. Internal devices. Working drawings;

STP OmGUPS–1.1–02. Works student educational and final qualifying. Basic provisions;

STP OmGUPS–1.3–02. Works student educational and final qualifying. General rules for the design of drawings;

STP OmGUPS–1.4–02. Works student educational and final qualifying. General rules for the implementation of schemes;

STP OmGUPS–1.11–03. Works student educational and final qualifying. Rules for the design of construction drawings.

3 Terms and definitions

3.1 Thermal scheme - a type of energy scheme, which, using conventional graphic symbols, shows the main and auxiliary equipment of a heat and power facility (boiler house, CHPP, TPP, etc.), combined by pipeline lines for transporting heat carriers in the form of steam or water.

3.2 Depending on the main purpose, the thermal scheme can be structural, principal, connections (assembly).

3.2.1 Structural diagram - a diagram that defines the main functional parts of the product, their purpose and relationships. Structural diagrams are developed when designing products (installations) at stages preceding the development of other types of diagrams, and are used for general familiarization with the product (installation). In the thermotechnical literature, such a scheme is called a principle.

3.2.2 Schematic diagram (complete) - a diagram that determines the complete composition of the elements and the relationships between them and, as a rule, gives a detailed idea of ​​the principles of operation of the product (installation). Schematic diagrams are used to study the principles of operation of products (installations), as well as during their adjustment, control and repair. They serve as the basis for the development of other design documents, such as wiring diagrams (installation) and drawings. In the thermotechnical literature, such schemes are called deployed.

3.2.3 Connection diagram (installation) - a diagram showing the connections of the component parts of the product (installation) and determining the pipelines that make these connections, as well as the places of their connections and input. Connection diagrams (installation) are used in the development of other design documents, primarily drawings that determine the laying and methods of fastening pipelines in a product (installation), as well as for making connections, when monitoring, operating and repairing products (installations). In the thermotechnical literature, such a scheme is called a working scheme, it is usually performed in an orthogonal, and individual complex nodes in an axonometric image.

3.3 In the main inscription, the name of the circuit is indicated in full, for example: Thermal circuit.

3.4 The designation of the scheme should be composed of the letter "P" (energy scheme) and the number 1 (structural), 3 (principal) or 4 (installation).

When carrying out construction and installation and other special works, a special place is occupied by the laying of main steel pipelines.

All communications are divided into 10 main groups in relation to the substances they transport, and therefore it became necessary to identify and mark linear routes.

Marking in Russia has passed the stage of standardization, requiring the mandatory use of GOSTs. Failure to comply with the rules is prosecuted by law, and also threatens the population with accidents, injuries, disruption of the production cycle, man-made disasters.

Color marking of pipelines

Pipelines are marked with the appropriate color, numbers, warning signs, special shields, which allows even an inexperienced specialist to determine the content and risk level of linear systems.

Color gradation when marking pipelines

Color marking of pipelines corresponds to GOST 14202-69. According to this rule:

• green color corresponds to group 1, transports water;
• red color corresponds to group 2, transports steam;
• blue color corresponds to group 3, transports air;
• yellow color corresponds to 4-5 groups, transports combustible and non-combustible gases;
• orange color corresponds to group 6, transports acids;
• purple color corresponds to group 7, transports alkalis;
• brown color corresponds to 8-9 groups, transports flammable and non-flammable liquids;
• gray color corresponds to group 0, transports other substances.

Important! Fire protection systems, regardless of the internal component, are always painted signal red. If necessary, they additionally use other means of notation.

Requirements for dyes

Marking of pipelines taking into account all characteristics

The coloring with which decals are applied must be resistant to chemicals and weather conditions, since marking of communications is necessary both in the industrial sector and in residential complexes. GOST 14202-69 does not apply to electrically conductive networks.

There are several ways to apply paint to systems.

The continuous painting method is applied if the pipeline is short and consists of a small number of connections.

With a large number of components of wired networks, long kilometers, and also if the architecture of the building does not imply large areas of coloring, coloring is used in separate fragments. The rest of the pipeline is tinted to match the color of the walls, ceiling, floor, etc. In the case when communications are located outside buildings and structures, the color should reduce the thermal effect on the pipes.

The size of the coating also depends on the outer diameter of the pipes. In the event that the diameter is large, the color designation is applied in the form of stripes with a height of at least 1/4 of the pipe circumference.

According to GOST, the paint is applied to the most important and critical areas, for example, at the joints and passage of pipes through walls, ceilings, floors, etc., at flanges, at sampling and control points, in the area of ​​\u200b\u200bentrance and exit to the room and from it after 10 -meter sections inside the building and after 30-60 m outside.

All pipeline marking data in the table

Important! On pipelines with increased pressure, connecting flanges are subject to painting, since the linear systems themselves are in protective casings.

Marking communications with various devices

In the event that the contents of communications are particularly aggressive, warning rings are applied to them in one of three colors: red corresponds to flammability, flammability and explosiveness; yellow color - dangers and harmfulness (toxicity, radioactivity, the ability to cause various types of burns, etc.); the green color with a white border corresponds to the safety of the internal content. The width of the rings, the distance between them, the application methods are standardized by GOST 14202-69.

Network marking is possible with the help of stickers. In the event that the sticker contains text, it is made in a clearly distinguishable font, without unnecessary symbols, words, abbreviations, in the maximum accessible syllable. Fonts comply with GOST 10807-78.

Stickers are also made in the form of arrows showing the direction of the flow of the substance inside the pipe. The arrows are also standardized in terms of size. The designation on the arrows is differentiated: “flammable substances”, “explosive and fire hazardous”, “poisonous substances”, “corrosive substances”, “radioactive substances”, “attention - danger!”, “flammable - oxidizer”, “allergic substances ". The color of the arrows, as well as the inscriptions, is applied in black or white, in order to achieve the greatest contrast with respect to the main coating of the pipe.

With a particularly dangerous communication component, stickers are made in the form of warning signs (in addition to color rings). The signs are triangular in shape with a black image on a yellow background.

Important! In plumbing systems with hot water and in the case of transporting leaded gasoline, the inscriptions must be white.

If the contents of the pipeline can damage the color designation, change its shade, special shields are used as additional markings, which are informative in nature, digital and alphabetic. The requirements for the graphics of the shields are identical to those of the stickers. Dimensional characteristics of the shields correspond to the characteristics of the arrows. Labeling boards should be located in clearly visible places, if necessary, illuminated by artificial lighting without interference for viewing by maintenance personnel.

Types of coatings

To cover linear systems, a paintwork material is used that corresponds to GOST and depends on the internal component, the physico-chemical composition of the pipes, their insulating characteristics, and also on the cost of the paint.

In rooms where there is no aggressive environment, good ventilation has been established, it is possible to use enamels in accordance with technical documentation.

Marking must be carried out strictly in accordance with safety regulations in order to avoid accidents and injury hazards.

Periodically, all marking products are subject to renewal to restore the original color.

High-quality and timely marking of main pipelines is not only safe, but economically beneficial due to the absence of accidents at the serviced facilities. And the use of GOSTs will also protect the enterprise from criminal or administrative liability.

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A brief overview of the regulatory documentation for marking pipelines at heat supply facilities

VII. Painting and inscriptions on pipelines

7.1. Depending on the purpose of the pipeline and the parameters of the medium, the surface of the pipeline must be painted in the appropriate color and have markings.

Coloring, symbols, letter sizes and location of inscriptions must comply with state standards.

7.2. Pipelines shall be marked with the following inscriptions:

a) on main lines - the number of the main line (in Roman numerals) and an arrow indicating the direction of movement of the working medium. If in normal mode it is possible to move it in both directions, two arrows are given, directed in both directions;

b) on branches near the mains - the number of the main (in Roman numerals), unit numbers (in Arabic numerals) and arrows indicating the direction of movement of the working medium;

c) on branches from the mains near the units - the number of the main (Roman numeral) and arrows indicating the direction of movement of the working medium.

7.3. The number of inscriptions on the same pipeline is not standardized. The inscriptions must be visible from the control points of valves, gate valves, etc. In places where pipelines exit and enter another room, inscriptions are required.

7.4. When covering the surface of the pipeline insulation with metal sheathing (sheets of aluminum, galvanized iron and other corrosion-resistant metals), the sheathing may not be painted along the entire length. In this case, depending on the transported medium, appropriate symbols must be applied.

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Identification painting of pipelines

Protective painting of pipelines is the main way to prevent corrosion and aggressive environmental influences on the pipe material. The main task of protective painting is to prevent contact of the pipeline with the environment in the entire range of operating parameters of the pipeline.

A completely different, but no less important function is performed by an obligatory element of pipeline marking - identification coloring of pipelines. It is designed to quickly identify the substance transported through the pipeline and its degree of danger.

Regulatory documentation for identification painting of pipelines

Each industry has a number of regulatory documents that regulate the issues of identification painting of pipelines, however, all these documents either refer to or repeat the requirements of the main standard for identifying pipelines in the Russian Federation - GOST 14202.

Such unification of the marking makes it possible to unambiguously determine the contents of the pipeline at any facility - from a small modular boiler house to a nuclear power plant and an oil refinery.

Exceptions to which the requirements of GOST 14202 do not apply are pipelines with medical gases, ship and aviation pipelines.

Identification painting of pipelines provides for color identification depending on the transported medium, as well as the application of warning rings that determine the degree of danger of the contents of the pipeline.

There are ten enlarged groups of substances, each of which corresponds to a certain color (table 1):

Often identification and protective colors are combined - a coating of the color that characterizes the transported medium is applied to the pipeline.

However, in many cases this is not possible, for example:

• - the protective coating required under specific conditions has a color different from that required in accordance with GOST 14202;
• - a heat-insulating structure is mounted on the pipeline;
• - the pipeline already has a factory protective coating;
• - the pipeline is made of non-ferrous metal and its coloring is not required.

In these cases, the standard allows protective painting not along the entire length of the pipeline, but in sections.

With this method, the use of marking tapes of various colors is much more efficient. They are easier and faster to apply to the pipeline, and the durability and presentability of such markings are much higher.

The width of the colored sections for pipelines with a diameter (including thermal insulation) up to 300 mm must be at least four diameters, and for pipelines with a diameter of more than 300 mm - at least two diameters. On pipelines of large diameters, it is allowed to apply the color in the form of strips with a height of at least ¼ of the pipeline circumference.

The intervals for applying the identification coloring of pipelines should be no more than 10 meters indoors, as well as on outdoor installations, and no more than 60 meters on external main pipelines.

Elements of identification coloring should be applied at the passage of pipelines through walls and ceilings, at the installation sites of stop valves, at the inputs and outputs in buildings and installations.

More details on the requirements for the identification coloring of pipelines can be found in GOST 14202.

Table 3 - Number of warning rings
Group	Number of warning rings	Substance being transported	Pressure in kgf/cm²	Temperature in °C
1	One	superheated steam	up to 22	250 to 350
Hot water, saturated steam	16 to 80	St. 120
	1 to 16	120 to 250
	up to 25	From minus 70 to 250
	Up to 64	From minus 70 to 350
2	Two	superheated steam	Up to 39	350 to 450
Hot water, saturated steam	80 to 184	St. 120
	Up to 16	From minus 70 to 350
Combustible (including liquefied and active gases, flammable and combustible liquids)	25 to 64
Non-flammable liquids and vapors, inert gases	64 to 100
3	Three	superheated steam	Regardless of the pressure	450 to 660
Hot water, saturated steam	St. 184	St. 120
	Regardless of the pressure	From minus 70 to 700
	St. 16	From minus 70 to 700
Combustible (including liquefied and active gases, flammable and combustible liquids)	Regardless of the pressure	350 to 750
Non-flammable liquids and vapors, inert gases	Regardless of the pressure	450 to 700

If it is necessary to apply yellow rings to pipes with gas (yellow) or acids (orange), their readability will be difficult. For this case, GOST 14202 provides for the implementation of a black border on the warning rings with a width of at least 10 mm.

A similar requirement applies in the case of applying green rings to a pipeline with water (also green) - white borders with a width of at least 10 mm are applied along the edges of the rings.

To simplify the work of applying colored warning rings to pipelines, self-adhesive marking tapes, which, if necessary, can already contain borders of the required color, can be used.

However, even more effective is the use of tapes that simultaneously have a background color corresponding to the group of the transported substance and the necessary warning rings. In this case, the cost and speed of applying the identification coloring of pipelines is significantly reduced.

An example of marking pipelines with self-adhesive tapes

An obligatory element of identification coloring is the placement of schemes and posters in accessible places of the premises or site of the enterprise indicating the relevant requirements of GOST 14202.

To specify the substances transported through pipelines and their parameters, it is necessary to use markings or shields in accordance with the requirements of GOST 14202. The shields must contain the name of the substance, the direction of its movement, as well as the corresponding danger signs. The color, shape, size and font of the inscription must comply with the requirements of the aforementioned standard.

Familiarize yourself with the range of marking products for pipelines.

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Color marking / coding / painting of general industrial pipelines (pipes). Regulatory documentation for the identification coloring of pipelines GOST 1402

In each industry, there are a number of regulatory documents that regulate the issues of identification painting of pipelines, however, all these documents either refer to or repeat the requirements of the main standard for identifying pipelines in the Russian Federation - GOST 14202. Such unification of the marking allows you to unambiguously determine the contents of the pipeline at any object - from a small modular boiler house to a nuclear power plant and an oil refinery. Exceptions to which the requirements of GOST 14202 do not apply are pipelines with medical gases, ship and aviation pipelines.

Basic requirements for identification painting of pipelines

Identification painting of pipelines provides for color identification depending on the medium being transported, as well as the application of warning rings that determine the degree of danger of the contents of the pipeline. There are ten enlarged groups of substances, each of which corresponds to a specific color (table 1):

Table 1 - Colors of identification coloring / marking / coding of pipelines depending on the working medium in the pipeline
Substance being transported	Samples and name of colors of identification coloring
Group number	Name
1	Water	Green
2	Steam	Red
3	Air	Blue
45	Combustible gases Non-combustible gases	Yellow
6	acids	Orange
7	alkalis	Violet
89	Flammable liquidsNon-flammable liquids	Brown
10	Other substances	Grey

Often identification and protective colors are combined - a coating of the color that characterizes the transported medium is applied to the pipeline. However, in many cases this is not possible, for example:

• the protective coating required under specific conditions has a color different from that required in accordance with GOST 14202;
• a heat-insulating structure is mounted on the pipeline;
• the pipeline already has a factory protective coating;
• the pipeline is made of non-ferrous metal and its coloring is not required.

In these cases, the standard allows protective painting not along the entire length of the pipeline, but in sections. The width of the colored sections for pipelines with a diameter (including thermal insulation) up to 300 mm must be at least four diameters, and for pipelines with a diameter of more than 300 mm - at least two diameters. On pipelines of large diameters, it is allowed to apply the color in the form of strips with a height of at least 1/4 of the pipeline circumference. The intervals for applying the identification coloring of pipelines should be no more than 10 meters indoors, as well as on outdoor installations, and no more than 60 meters on external main pipelines. Elements of identification coloring should be applied at the passage of pipelines through walls and ceilings, at the installation sites of stop valves, at the inputs and outputs in buildings and installations. More details on the requirements for the identification coloring of pipelines can be found in GOST 14202.

It is also mandatory to apply warning rings that carry information about the degree of danger of the medium in the pipeline. The color and number of rings are shown in tables 2-3, and the application scheme is in drawing 1.

Now about the number of rings:

Table 3 - Number of warning rings depending on the pressure and temperature of the working medium in the pipeline
	Number of warning rings	Substance being transported	Pressure in kgf/cm2	Temperature in °C
		superheated steam	up to 22	250 to 350
Hot water, saturated steam	16 to 80	St. 120
Superheated and saturated steam, hot water	1 to 16	120 to 250
Combustible (including liquefied and active gases, flammable and combustible liquids)	up to 25	From minus 70 to 250
Non-flammable liquids and vapors, inert gases	Up to 64	From minus 70 to 350
		superheated steam	Up to 39	350 to 450
Hot water, saturated steam	80 to 184	St. 120
Products with toxic properties (except for highly toxic substances and fuming acids)	Up to 16	From minus 70 to 350
Combustible (including liquefied and active gases, flammable and combustible liquids)	25 to 64	250 to 350 and minus 70 to 0
Non-flammable liquids and vapors, inert gases	64 to 100	From 340 to 450 and from minus 70 to 0
		superheated steam	Regardless of the pressure	450 to 660
Hot water, saturated steam	St. 184	St. 120
Potent toxic substances (SDN) and fuming acids	Regardless of the pressure	From minus 70 to 700
Other products with toxic properties	St. 16	From minus 70 to 700
Combustible (including liquefied and active gases, flammable and combustible liquids)	Regardless of the pressure	350 to 750
Non-flammable liquids and vapors, inert gases	Regardless of the pressure	450 to 700

If it is necessary to apply yellow rings to pipes with gas (yellow) or acids (orange), their readability will be difficult. For this case, GOST 14202 provides for the implementation of a black border on the warning rings with a width of at least 10 mm. A similar requirement applies in the case of applying green rings to a pipeline with water (also green) - white borders with a width of at least 10 mm are applied along the edges of the rings.

It is no coincidence that polypropylene pipelines are becoming increasingly popular with home craftsmen and professional installers. Polypropylene pipes have a number of advantages due to which they are gradually replacing products from traditional materials. The choice of plastic pipes today is simply huge and all products differ in their characteristics and purpose. To find out which of them are suitable for a heating system, cold or hot water supply, ventilation, decoding the marking of polypropylene pipes will help.

"Reading" information

• The name of the manufacturer usually comes first.
• Next comes the designation of the type of material from which the product is made: PPH, PPR, PPB.
• On pipe products, the working pressure must be indicated, which is indicated by two letters - PN, - and numbers - 10, 16, 20, 25.
• Several numbers indicate the diameter of the product and the wall thickness in millimeters.

• On domestic modifications, the class of operation in accordance with GOST may be indicated.
• The maximum allowed.

Additionally indicated:

1. Regulatory documents in accordance with which pipe products are manufactured, international regulations.
2. Quality mark.
3. Information about the technology by which the product is made, and the classification according to MRS (Minimum Long-Term Strength).
4. 15 digits containing information about the date of production, batch number, etc. (the last 2 are the year of manufacture).

And now let us dwell in more detail on the most important characteristics of polypropylene pipes indicated in the marking.

Material and scope

Manufacturers from different countries use slightly different designations, but the PP marking will definitely be present, demonstrating that the pipe is made of polypropylene. Additional letters or numbers indicate a specific type of this material that has its own properties.

1. PRN (PP-type 1, PP-1) - the pipe is made of a homopolymer. Due to the characteristics of this type of polypropylene, it is intended only for cold water, as well as for ventilation.
2. РРВ (РР-type 2, РР-2) – the product is made of a block copolymer. It can be used for cold water supply and in low-temperature types of heating systems.
3. PPR (PP-2, PPR, PP-random, PPRC) - the pipe is made from a random copolymer. Products with this marking are most common due to their versatility. Due to the increased heat resistance, they can be used in heating systems of any kind, as well as for supplying hot and cold water to apartments and houses.

Rated pressure

The letters PN are the designation of the permitted working pressure. The next figure indicates the level of internal pressure in bars that the product can withstand during a service life of 50 years at a water temperature of 20 degrees. This indicator directly depends on the wall thickness of the product.

• PN10. This designation has an inexpensive thin-walled pipe, the nominal pressure in which is 10 bar. The temperature maximum that it can withstand is 45 degrees. Such a product is used for pumping cold water and underfloor heating.

• PN16. Higher nominal pressure, higher limiting liquid temperature - 60 degrees Celsius. Such a pipe is significantly deformed under the influence of strong heat, therefore it is not suitable for use in heating systems and for supplying hot liquids. Its purpose is cold water supply.

• PN20. The polypropylene pipe of this brand can withstand a pressure of 20 bar and temperatures up to 75 degrees Celsius. It is quite versatile and is used to supply hot and cold water, but should not be used in a heating system, since it has a high coefficient of deformation under the influence of heat. At a temperature of 60 degrees, a segment of such a pipeline of 5 m is extended by almost 5 cm.

• PN25. This product has a fundamental difference from previous types, since it is either fiberglass. In terms of properties, the reinforced pipe is similar to metal-plastic products, is less susceptible to temperature effects, and can withstand 95 degrees. It is intended for use in systems of heating, and also in GVS.