Non-metallic and composite materials. Gaskets, sealing and insulating materials Types of gaskets and sealing materials
Electrical materials. Various power cables are used to power electrical equipment used in plumbing work.
Flexible power cables for voltage up to 220 V according to GOST 6731-77E are manufactured in the following grades: RGD - with rubber-insulated copper conductors; RGDO - with copper conductors with a rubber sheath; RGDV - with a main conductor and insulated auxiliary conductors with a common rubber insulation with protective properties. Cables are used to connect electrode holders of automatic or semi-automatic devices with a source of rated alternating voltage up to 220 V, frequency 50 Hz or direct voltage. The cables are designed to operate at temperatures environment from -50 to +50 °С. The construction length of the cables is at least 100 m.
Flexible power cables for a voltage of 660 V according to GOST 13497-77E are produced in the following grades: KRPT - with copper conductors with rubber insulation in a rubber sheath; KRPTN - with copper conductors with rubber insulation in a rubber sheath, in a rubber oil-resistant sheath that does not propagate combustion; CRPG - with copper conductors of increased flexibility with rubber insulation in a rubber sheath; KRPGN - with copper conductors of increased flexibility with rubber insulation in a rubber oil-resistant sheath that does not spread combustion; KRPS - with copper conductors of increased flexibility with rubber insulation with a profiled core in a rubber sheath.
Cables are supplied in coils weighing no more than 50 kg or wound on wooden drums.
Rubber products. Flat rubberized fabric drive belts used in electric generators and electric pumps are made of three types depending on the purpose and design:
- type A - threaded, used for small pulleys at rotation speeds of more than 20 m / s; are made in width 20; 25; thirty; 40; 45; 50; 60; 70; 75; 80; 85; 90; 100; 125; 150 mm;
- type B - wrapped in layers, used when working with a discontinuous load at rotation speeds up to 20 m / s; are made 20 wide; 25; thirty; 40; 150; 200; 250 mm;
- type B - spiral wrapped, used when working with small loads at rotation speeds up to 15 m / s; from-are prepared with a width of 20; 25; thirty; 40; 50; 60; 75; 80; 85; 90; 100; 125; 150 mm.
Belts up to 90 mm wide are produced at least 8 m long; 100 mm wide or more - at least 20 m long.
The surface of the belts must be smooth, without exposing fabric pads, without knots, protruding threads and delaminations, without cracks, dents and blisters, pits, scars and mechanical damage.
V-belts in accordance with GOST 1284.1-80 consist of cord fabric or cord, wrapping fabric and rubber, connected into one whole by vulcanization.
The inner length of the belt corresponds to the length of its inner circumference, and the calculated length corresponds to the circumference at the level of the calculated belt width, measured under tension. Preferred calculated belt lengths are: 400; 450; 500; 560; 630; 710; 800; 900; 1000;1120;1250; 1400;1600; 1800; 2000; 2240; 2500; 2800; 3150; 3550; 4000; 4500; 5000; 5600; 6300; 7100; 8000; 9000; 10,000; 11 200; 12,500; 14,000; 16,000 and 18,000 mm.
In operation, the belts must remain operational in the temperature range from -30 to +60 °C.
Rubber pressure hoses with a textile frame (according to GOST 18698-79) are used as flexible pipelines for supplying liquids, gases and bulk materials under pressure. Depending on the purpose and working conditions, these hoses are manufactured in the following types: B - for supplying gasoline, kerosene, oil and mineral oils; B - for supplying water and weak solutions inorganic acids and alkalis with a concentration of up to 20%; VG - for filing hot water temperature up to 100 °C; G - for supplying air, oxygen, acetylene, carbon dioxide, nitrogen and other inert gases; P - for the supply of food substances; Ш - for supplying solutions at plastering works; Steam-1 and Steam-2 - for the supply of saturated steam.
Rubber-fabric pressure hoses with inner (nominal) diameter 10; 12.5; 16; 20; 25; 31.5; 40; 50 and 63 mm are made for operating pressure up to 2.0 MPa (20 kgf / cm 2); diameter 80; 100; 125; 160 and 200 mm - for working pressure up to 0.5 MPa (5 kgf / cm 2).
Hose of all types must be airtight when tested with hydraulic pressure equal to twice the working pressure, and type D hoses - when tested with air pressure equal to the working pressure. Sleeves of types B, V, P and Sh must have at least a threefold margin of safety, and sleeves of types VG, G, Par-1 and Par-2 - at least five times.
Sleeves of all types must remain operational in the temperature range from -35 to +50 °C.
Rubber sleeves for gas welding and cutting of metals (according to GOST 9356-75) are used for supplying acetylene under pressure, liquid fuel and oxygen to equipment for welding and cutting metals at ambient temperatures from -35 to +70 °С and from -55 to +70 °С in regions with a cold climate (table below).
Depending on the purpose, the sleeves are made in three types with a distinctive color of the outer rubber layer:
- type I - for the supply of acetylene, household gas, propane and butane under a pressure of not more than 0.63 MPa - red;
- type II - for supplying liquid fuel (gasoline, kerosene, white spirit) under a pressure of not more than 0.63 MPa - yellow;
- type III - for supplying oxygen under a pressure of not more than 2.0 MPa - blue.
Sleeves must have at least three times the tensile strength hydraulic pressure. On the outer surface of the sleeves there should be no bubbles, delaminations, dents and other defects; inner surface must be even, without folds, bubbles, etc.
Basic parameters of rubber sleeves
Pressure fire hoses (according to GOST 472-75) made of dry-spun linen yarn, depending on defects, are divided into the first and second grades.
Sleeves roll up into circles. At the outer end of each batch of circles put a brand, which indicates: 1) the name and address of the manufacturer; 2) inner diameter, mm; 3) name of the hose group; 4) sleeve length in a circle, m; 5) the mass of the circle and its number; 6) date of manufacture of ru-kava (year, month); 7) designation of each standard.
Stuffing, sealing and lining materials. For the production of plumbing work, the industry produces a number of auxiliary materials needed to seal the joints.
Stuffing box packings (according to GOST 5152-77) are used for sealing glands in fittings, pumps, machines and equipment and are designed for a wide range of pressures and temperatures. Packings impregnated with an anti-friction compound promise lubrication of rotating shafts and rods passing through the stuffing box.
Asbestos cords (according to GOST 1779-72) impregnated with an anti-friction compound or graphite mixed with natural drying oil are used for stuffing fittings, compensators, sealing sections of cast-iron boilers, threaded connections, and also as an insulating material.
Asbestos cardboard (according to GOST 2850-75) grades KAON-1 and KAON-2 is used as a heat-insulating and fire-retardant material at an insulated surface temperature of not more than 500 ° C, as well as a gasket material for equipment, instruments and communications. Cardboard brand KAP serves as a cushioning material. Cardboard sheets should not have cracks, dents, foreign mechanical inclusions.
Gasketboard (according to GOST 9347-74) is produced in sheets and rolls with a density of 0.7-0.75 g / cm 3 of two grades - A (impregnated) with a thickness of 0.3; 0.5; 0.8; 1; 1.5 mm; B (unimpregnated) - 0.3 thick; 0.5; 0.8,; 1; 1.25; 1.5; 1.75; 2; 2.25; 2.5 mm. Gaskets are made from cushioning cardboard for sealing flange joints of pipelines transporting water with a temperature of up to 100 ° C. Before installing the gasket, it is necessary to moisten it in water and boil it in natural drying oil. The surface of the cardboard must be even, without warping, wrinkles, wrinkles, bubbles, non-fibrous inclusions and pressure spots.
Rubber and rubber-fabric plates (according to GOST 7338-77), used for the manufacture of gaskets, valve seals, shock absorbers and other parts, are produced acid-alkali-resistant, heat-resistant, frost-resistant and oil-and-petrol-resistant. The length of sheets or strips of plates is 0.5-10 m, width 200-1750 mm, thickness 0.5-50 mm. Heat-resistant rubber plates remain operable when operating in an air environment with a temperature of up to 90 ° C and in a water vapor environment with a temperature of up to 140 ° C. Frost-resistant rubber plates remain operable under operating conditions at temperatures up to -45 ° C. Rubber plates of all types remain heat-resistant when operated within temperatures from -30 to +50 ° C. A sheet rubber plate is used for the manufacture of flange gaskets for pipelines cold water. The rubber-fabric plate is used at water temperatures up to 100 °C.
Paronite (according to GOST 481-71) is made from a mixture of asbestos fibers, solvent, rubber and fillers and is produced in the form of sheets with a thickness of 0.4; 0.6; 0.8; 1.5; 2; 3; 4; 5 and 6 mm, sizes 300x400, 400x500, 500x500, 750x1000, 100x x1500, 1500x1500 and 3000x1500 mm. Gaskets are made from general-purpose paronite for flanged connections of hot water and steam pipelines with temperatures above 100 ° C. Before installation, the gaskets are moistened in hot water and lubricated with graphite mixed with natural drying oil. Paronite cannot be stored together (in the same room) with organic solvents, lubricating oils, acids and other substances that destroy it.
Sheet fiber (according to GOST 14613-69) is produced in eight grades. For example, fiber of the FP K brand (oxygen-resistant gasket) is made with a thickness of 0.6 to 5 mm, and is used as gaskets for neutral gaseous media (oxygen, carbon dioxide, etc.) at high pressures And normal temperatures; fiber must be thoroughly degreased before use. Fiber brand FT (technical) is used as a sealant in valves and taps of hot water supply systems.
Flax torn (according to GOST 10330-76) in the form of a strand impregnated with minium or white lead diluted on natural drying oil is used as a sealant in threaded joints of pipelines transporting water with a temperature of up to 105 ° C.
FUM - fluoroplastic sealing materials in the form of a tape 10-25 mm wide and 0.08-0.12 mm thick and a cord (for flange gaskets). The tape is used to seal threaded connections pipelines D y< 65 мм, шнур — для Уплотнения контргаек, а также в качестве сальниковой набив-ки вентилей и кранов. Уплотнение из ФУМ водостойко и вы-держивает температуру от -60 до +200 °С.
A resin strand (kabolka) is a bast fiber treated with wood resin - a waste from the production of hemp and flax fibers. A strand of two grades is produced: the first grade is made from hemp fiber, the second grade is made from a mixture of hemp and flax fibers. The strand is used to seal the sockets of cast-iron and ceramic pipes.
Hemp rope (according to GOST 483-75), impregnated with resin (to protect against decay) or without impregnation, is used to seal the sockets of cast-iron and ceramic pipes.
Auxiliary materials. Drying oil natural linen and hemp (according to GOST 7931-76) is used for the preparation of red lead putty, dilution of primers and thickly ground paints, as well as for impregnation of cardboard gaskets. Drying oil should be stored in a tightly closed container.
Drying oil oksol (according to GOST 190-78) in some cases can serve as a substitute for natural drying oil. Produced by sealing linseed oil and blowing it with air in the presence of a desiccant, followed by the addition of a solvent (white spirit).
Minium lead (according to GOST 19151-73) is a heavy powder of bright red-orange color, five grades are produced: M-1, M-2, M-3, M-4 and M-5. Minium, diluted on natural drying oil (2 parts by weight of red lead and 1 part by weight of drying oil), is impregnated with a flax strand used as a sealant in threaded joints of heating pipelines with a coolant temperature of up to 105 ° C, pipelines hot water supply and gas supply.
White lead white (according to GOST 12287-77) in the form of a paste from a mixture of lead white, heavy spar and drying oil or raw linen or sunflower oil They produce three grades: MA-011, MA-011-N-1 and MA-OI-N-2. They serve the same purposes as red lead.
Thick zinc white (according to GOST 482-77) is a paste of dry zinc white (or a mixture of them with a filler), rubbed on natural linseed drying oil or vegetable oils with the addition of a desiccant, and is produced in seven grades: MM -00 special, M-00, M-0, V-2-00, V-2-0, V-4-00, V-4-0. These whites, after diluting them with natural glyptal or pentaphthalic drying oil to a painting consistency, are used for painting surfaces. For internal works dilution of white drying oil with oxol is allowed.
Zinc white, diluted with natural drying oil, is used to impregnate a linen strand used as a sealant in threaded joints of cold water pipelines.
Crucible graphite (according to GOST 4596-75) is used as an integral part of gland packings and mastics when connecting pipes, assembling cast-iron sectional boilers, impregnating paronite gaskets, etc.
When connecting pipeline parts to pipeline fittings, it is necessary to ensure the tightness of these connections in order to avoid leakage of the medium.
Leakage is especially dangerous when transporting aggressive and explosive media, as well as those under pressure and at high temperatures.
main type detachable connections pipelines are flanged connections, and its integral element is a gasket.
The gasket material must have the following properties:
ü elasticity, so that when pressure is created, the smallest irregularities of the flange surface are filled, ensuring the tightness of the connection;
ü strength, in order to withstand the force of the pressure of the environment;
ü Resistant to aggressive environments.
Depending on the purpose and working conditions pipe fittings cardboard, paronite, sheet asbestos, rubber, fluoroplast, polyethylene, aluminum, lead, copper, mild annealed steel are used as gasket materials.
The choice of gasket materials for sealing flanged joints depends on the transported medium and its operating parameters.
Some gasket materials depending on the medium parameters and types of sealing surfaces are presented in table 9.
Table 9 - Gasket materials depending on the parameters of the medium and types of sealing surfaces
Table 9 continued
| Gasket material | Working environment | Limiting temperature, 0 C | Operating pressure limit, MPa | ||
| smooth surface | ledge-depression | tenon-groove | |||
| 3. Oil and petrol resistant paronite (PMB) 4. Technical acid and alkali resistant rubber (KSh) 5. Technical oil and petrol resistant rubber (MB) 6. Technical heat resistant rubber (T) 7. Asbestos cardboard 8. Fluoroplastic 4 9. Annealed aluminum (AMC) 10. Sheet copper (M 2) 11. Lead grade C2 12. Corrugated asbestos-aluminum 13. Spiral steel 12X18H10T (filler - asbestos) | Light oil products Heavy oil products Oxygen, gaseous nitrogen Oxygen, liquid nitrogen Coke oven gas Water, air, neutral solutions, neutral gases and vapors, sulfuric acid (up to 65%), hydrochloric acid(up to 30%) Heavy petroleum products, kerosene, oils, butyl alcohol Steam, dry neutral and inert gases Liquid and gaseous hydrocarbons, fuel oil, oils, resins Acids, alkalis, solvents and organic liquids Liquid and gaseous hydrocarbons, fuel oil, oils , resins Superheated water, steam, liquid and gaseous petroleum products Solutions of sulfuric and acetic acid(up to 60%), liquefied chlorine Heavy and light oil products, hydrocarbon gases, flue gases, carbon dioxide Steam, dry gases, oil products | – 182 from minus 30 to 50 from minus 30 to 50 from minus 196 to 250 from minus 196 to 250 from minus 70 to 250 | 2,5 2,0 2,5 0,25 2,5 1,0 1,0 1,0 0,15 – 1,6 2,5 0,6 2,5 2,5 | – – 5,0 – 6,4 – – – – – 4,0 10,0 – 6,4 10,0 | vacuum – 5.0 – – – – – – 2.5 vacuum vacuum – – – |
Table 9 continued
For sealing glands of pipeline fittings and stuffing box expansion joints, packings are used in the form of cords woven from asbestos or hemp threads impregnated with various compounds that make them resistant to aggressive environments.
The material for stuffing glands is selected depending on the operating conditions. Fatty asbestos packing can be used at temperatures not exceeding 200 0 C, since at more than high temperatures fatty substances flow out, and the density of the omentum decreases.
At temperatures above 200 0 C, asbestos-programmed packing or special asbestos-metal packings are used, impregnated with a special composition that is resistant to destruction under the influence of transported media and high temperatures.
Fluoroplastic packing is used in the form of rings or a cord, which provides high resistance to acidic and alkaline media at temperatures up to 250 0 C.
Gland packing must be made of braided cord square section in width equal to the width of the stuffing box. Separate rings are cut from such a cord with ends beveled at an angle of 45 0. The rings should be placed in the stuffing box opposite the cut lines, with the sealing of each ring separately. During assembly, the bottom box should enter the chamber by at least 5 mm, but not more than 1/7 of its height.
Tightening of glands should be carried out evenly, without distortions of the bottom box.
QUESTIONS FOR SELF-CHECKING
1. By what main features can pipe fittings be classified?
2. What is a nominal diameter? What is conditional pressure?
3. What is a gate valve? What are the valves, where and how are they installed?
4. List the main advantages and disadvantages of valves in comparison with other types of pipeline fittings.
5. What is a valve? What are its main elements?
6. List the main advantages and disadvantages of the valve in comparison with other types of pipeline fittings.
7. What are the types of valve sealing surfaces?
8. What is a faucet? What types of cranes do you know?
9. List the main advantages and disadvantages of valves compared to other types of pipeline fittings.
11. What applies to safety and protective pipeline fittings?
12. How are pipeline fittings marked?
13. Decipher the marking of the following types of pipeline fittings: 15kp3p; 11h3bk; 30s64br.
14. For what reasons is the normal operation of pipeline fittings disturbed?
15. What is the revision of pipeline fittings, what does it consist of?
16. How is the repair of pipeline fittings (valve, gate valve, cock) carried out? What devices are used for this?
17. How is pipe fittings tested? What are the types of testing?
18. Formulate the basic principles for choosing pipeline fittings.
19. What properties should a gasket have?
20. List the main materials of gasket materials and their areas of application.
21. Up to what maximum temperature can PTFE be used as a gasket material?
23. How to properly stuff the stuffing box?
Sealing, insulating and upholstery materials
In the manufacture and operation of machines, it becomes necessary to seal the places where some parts come into contact with each other. In addition, the ability batteries support very big values current strength (hundreds of amperes), as well as the presence of high voltage in the ignition system (20 ... 30 kV) predetermined high requirements to insulating materials.
Usage upholstery materials improves the appearance of the cabin, interior, body, increases comfort.
Consider the sealing, insulating and upholstery materials used in the automotive industry.
Sealing materials are divided into two groups - gaskets and stuffing.
Gasket materials are used when it is necessary to seal the detachable parts of the engine, transmission housings and other components. Gaskets sometimes regulate gaps or forces in contact pairs.
Packing materials are used to seal gaps between moving pairs of parts, as well as to protect friction units from dust, dirt and water.
Sealing materials are divided into paper, asbestos, rubber, felt, cork and plastic. Sometimes as sealing materials use soft materials: aluminum, lead and copper.
Paper interlining materials include paper, cardboard, fiber and parchment. paper materials up to 0.5 mm thick and specific gravity up to 250 g / m 2 is conventionally referred to as paper, and larger mass and thickness - to cardboard. Cardboards are divided into cushioning, container, construction, decorative, etc.
Interleaved cardboard is a relatively elastic, oil and petrol resistant material, produced with a thickness of 0.2 ... 1.5 mm. The surface of the cardboard sheet must be even, and the thickness must be constant over the entire area.
As a substitute for cushioning cardboard, technical cardboard or drawing paper is used. To increase porosity, they are wetted hot water until completely saturated and then dried. The pores are filled with impregnation for 20 ... 25 minutes, heated to 60 ... 70 0 With vegetable oil or drying oil.
Parchment- transparent oil and grease resistant moisture resistant paper. It is obtained by treating unglued paper with sulfuric acid, followed by its neutralization with an alkali solution.
Fiber - cushioning material, obtained by treating unglued paper or cardboard with a solution of zinc chloride, which gives the material high strength and also oil resistance. When operating the nodes, it must be borne in mind that high hygroscopicity (up to 60 ... 65%) leads to the fact that the fiber warps when moistened.
Fiber is available in several grades:
FSV - special, high-strength (for the manufacture of particularly durable products);
FT - technical, for the manufacture of parts in mechanical engineering and instrumentation;
FE - electrical, for the manufacture of electrically insulating parts;
KGF - castor-glycerine, is used as a sealing material that protects against leakage of water, oil, kerosene and gasoline.
Fiber is made in the form of sheets with a width of 1.1...1.4 m and a length of 1.7...2.3 m, a thickness of 0.4...25.0 mm and a density of at least 1100 kg/m 3 .
A common disadvantage of paper cushioning materials is their low heat resistance. At temperatures above 130...140 0 C, paper and cardboard lose their flexibility, become brittle, at 180 0 C charring (blackening) begins, and at 240...250 0 C, paper fibers completely decompose.
Asbestos- natural mineral (chrysotilasbest). It has a fibrous structure, capable of splitting (fluffing) into the thinnest flexible and strong fibers, which are rhomboid-shaped whisker crystals. Density of lump asbestos is 2000...2500 kg/m 3 , and asbestos products without fillers - 1000...2000 kg/m 3 . Asbestos does not burn, heat-resistant, good dielectric. It easily withstands heating up to 300 0 С, and at 386 0 С it loses adsorbed water, which reduces its strength and flexibility (reversible phenomenon). When heated above 450 0 C, water is lost irreversibly. The process ends at 700 ... 800 0 C, asbestos becomes fragile, easily pounded into powder. The strength of asbestos depends on temperature: from 315...320 kgf/cm 2 at 20 0 C to 70...80 kgf/cm 2 at 600 0 C.
Depending on the length of the fibers, asbestos is divided into nine grades with various purposes. So, for the manufacture of fabrics, cords, threads of stuffing boxes, insulating roving, woven tapes and similar textile products, asbestos grades AK are used; 1st, 2nd and 3rd rigid texture and 2nd semi-rigid texture grade (with fiber length 6...18 mm).
For the manufacture of paronite, electronite, asbestos cardboard and asbestos paper, varieties of the 3rd and 4th semi-rigid and soft textures are used.
For the production of asbestos cardboard and other insulating products, the 6th grade of asbestos is used (fiber length 1 ... 1 mm).
Asbestos, as having high heat resistance, is used as a sealing material operating at elevated temperatures (gaskets exhaust manifold, muffler). When asbestos is used as gaskets for engine block (cylinder) heads, it is enclosed in a copper or steel sheath (foil) to prevent contact with hot gases. Damage to the shell leads to contact, loss of constitutional (part of) water and rapid destruction.
For various auxiliary equipment asbestos cardboard, asbestos cords and threads, paronite, as well as crushed asbestos for thermal insulation work are used.
Asbestos cardboard and paper are used for fire protection, thermal insulation, electrical insulation and sealing.
Asbestos cardboard is produced in the form of sheets with a thickness of 2 ... 10 mm and sizes of about one square meter. Density 1000 ... 1300 kg / m 3, thermal conductivity coefficient (for 20 ... 100 0 С) - 0.13 kcal / m × h × deg.
Asbestos paper is produced in rolls 0.25...1.0 mm thick, 670...1150 mm wide.
paronite- cushioning sheet material from rolled asbestos with rubber (with sulfur) binder and mineral fillers in the ratio: 60...75% - 12...13%. Clay, feldspar, talc, etc. are used as mineral fillers.
Paronite is used as gaskets for timing gear covers, oil receiver tube flanges, water pump, fuel sump, etc.
Paronite is produced in the following brands:
MON - general purpose;
PMB - oil and petrol resistant;
PA - reinforced with steel mesh.
Sheet thickness 0.4 ... 3 mm, length - up to 3 m and width - up to 1.5 m.
Asbestos fabrics serve for thermal insulation, production of fire-resistant overalls and blankets, omental packings, production of asbestos-textolite. To increase the strength, cotton fibers are added to asbestos fabrics, reinforced with brass wire or glass threads. The width of asbestos fabrics is 1040...1550 mm, the thickness is 1.2...3.8 mm.
Asbestos cords and threads- are used for omental packings and heat-insulating windings. Making cords three varieties:
asbestos cord from twisted asbestos threads;
asbestos cord from combed asbestos and cotton fibers braided with asbestos cords;
asbestos-magnesia cord with a core of magnesia and asbonite, also braided with asbestos threads (for thermal insulation of surfaces with temperatures up to 550 ... 600 0 С; thermal conductivity coefficient 0.080 ... 0.150 kcal / m × h × hail).
asbestos tapes serve for thermal and electrical insulation. Thickness 0.4...1.4 mm, width 13...250 mm.
Asbestos steel sheets are used for cutting out shaped gaskets. Six stamps, dimensions: length 215...875 mm, width 500 and thickness 1.4...1.75 mm.
It should be noted that in recent years, for reasons of reducing the harmful effects on humans, the volume of use of asbestos products has been decreasing.
Cork cushioning materials- obtained by pressing grits of cork oak bark and used to seal joints operating at low voltage in the environment of water or oil products:
engine valve box covers;
fuel pump filter cups;
crankcase ventilation filter;
engine crankcase;
block head covers;
rocker covers, etc.,
and also as packing of an epiploon of a needle bearing.
Gasket felt is a sheet material made from wool fibers. Technical felt is divided into:
fine-haired;
semi-coarse;
coarse.
Felt is a porous material in which air pores make up at least 75% of the volume. Felt density 200...430 kg/m 3 .
Felt has high heat-, sound-insulating and shock-absorbing properties. The thermal resistance of felt does not exceed 75 0 С.
Felt wool fibers are destroyed by the action of fungi and moths, unstable against alkalis, but resistant against acids.
Related articles:
Timely repair plumbing devices prevents emergencies and creates the conditions for trouble-free long-term operation of home plumbing. In addition to the fact that a home plumber prevents a lot of trouble on the scale of his high-rise building, he also saves family money by repairing a faulty plumbing fixture in time, while it can be done. The ability to repair a “broken” device is valuable because it is not always possible to replace it with a new one due to financial difficulties or due to the lack of a similar analogue on sale.
Most faults household plumbing associated with wear of seals, gaskets, corrosion of parts. The technical solutions to the problems that arise in this case are:
Gaskets, sealing and stuffing materials in household plumbing
The household plumbing system of each house or apartment consists of plumbing fixtures and communications, consisting of rigid or flexible pipelines. To connect them into a single workable system, threaded, flanged or other methods of mating components and parts are used. Most interfaces must be detachable in order to ensure the maintainability of the system and the replacement of failed elements. In this case, the requirements for ensuring the tightness of the connections increase in order to prevent flooding of one's own home and causing damage to neighbors.
The tightness of the connections of the elements of the household plumbing system is ensured by gaskets, sealing and stuffing materials. The need for their presence in the arsenal of home plumbing is due to the fact that during repair and maintenance work, these materials are almost completely replaced with new ones.
Currently traditional ways sealing of plumbing connections is confidently crowding out new assembly technologies using silicone sealants. Every plumber has in his arsenal a plastic tube of plumbing silicone sealant and a gun for squeezing the sealant out of the tube. 
Materials for seals and gaskets
The purpose of seals is to prevent air from entering plumbing fixture, if it works under subatmospheric pressure, and do not allow water to leak from the hydraulic system if it is under excessive pressure. Sealing is achieved by placing a soft elastic material between the surfaces of the parts in order to create the smallest possible gap between them. In practice, gaskets made from gasket materials or sealing materials are used. Home craftsman it is enough to have a certain range of gasket materials in your workshop in order to independently, in place, produce a gasket of the required shape and size.
Paronite is a flexible sheet gasket material made using the technology of pressing asbestos, rubber, mineral fillers, sulfur and solvents. Sheet paronite is produced in accordance with GOST 481-80 “Paronite and gaskets from it. Specifications» sheets with a thickness of 0.4 to 6.0 mm and sizes from 300 x 400 mm to 3000 x 1500 mm. Paronite gaskets are used in the operating temperature range of coolants from - 60 0 С to + 450 0 С. The main condition for the effective use of paronite gaskets is that the sealed connectors must be flat. 
PON paronite (general purpose paronite) is used for the plumbing of our dwelling, capable of operating at temperatures from -50 0 С to + 450 0 С in a water or steam environment, in an aqueous solution of salts, oil products. Ring gaskets are made of paronite in all flange connections of pipelines in which the coolant temperature exceeds 100 0 С (hot water and steam), as well as for sealing threaded and socket joints. Before installation, paronite gaskets must be moistened with hot water and lubricated with graphite mixed with drying oil.
At joint storage V common room paronite must be stored separately from organic solvents, acids and lubricating oils that have a destructive effect on it.
Technical rubber
For the manufacture of sealing gaskets for flange joints of pipelines of cold and hot water, technical rubber GOST 7338-90 “Rubber and rubber-fabric plates. Specifications". Products made of rubber and rubber-fabric plates have proven themselves in sealing fixed joints (flanged joints) in cold and hot water pipelines. In accordance with GOST 7338−90 plates are produced in two types:
On the pictures: pos. 1 - rubber, pos. 2 - fabric.
In the manufacture of rubber-fabric plates, the condition is observed - for every 2 mm of the rubber layer of the plate there should be no more than one layer of fabric.
Technical rubber gaskets are made 3-4 mm thick and are used as follows:
- For pipelines with cold water- rubber gaskets;
- For pipelines with hot water up to 100 0 C - gaskets made of rubber-fabric plates.
Most plumbers keep kits with them. rubber gaskets factory-made, without bothering to homemade performance using a puncher. 
FUM tape, FUM cord
Sealing fluoroplastic materials in the form of tape or cord are widely used in household plumbing.
To seal threaded connections on pipes up to D y \u003d 65 mm, FUM tape is used, and the FUM cord is used for sealing flanges, locknuts and as stuffing box packing for valves. Seals made of FUM (fluoroplastic sealing material) are waterproof, withstand temperatures from -60 0 C to +200 0 C. Fluoroplast-4 is used as a blank for the production of FUM tape or cord. The FUM tape is produced in accordance with GOST 24222-80 “Film and tape from fluoroplast-4. Specifications "with a width of 10 to 25 mm and a thickness of 0.08 to 0.12 mm, cords are produced in accordance with TU 6-05-1570-86" Fluoroplastic sealing material. Specifications” round and square section. 
Technical leather
Gaskets and cuffs are made from technical leather GOST 20836−75 for connecting valves and taps to cold water supply pipelines. It is not recommended to contact leather pads with hot water, since tannins are washed out of the leather with hot water, and the material itself loses its elasticity. 
Ragged linen and linen tow
Worn linen is a classic winding seal. The main advantages of flax as a sealing material:
- Possibility of use for any kind of connections;
- The increase in its volume during swelling. Linen fibers swell when wet and block small leaks. If there is a slight leak immediately after flax fiber compaction, it will a short time"closes";
- The mechanical resistance of the fibers, which makes it possible to make changes in the orientation of sanitary fittings by means of a return rotation within a full turn without loss of tightness.
Quite often, tattered flax is mistakenly called tow. The confusion comes from the method of compaction, when linen strands or tangled tow are straightened into individual fibers and wound onto threads. Outwardly, it is difficult to distinguish, but there are significant differences in the purity of the material. 
Among the disadvantages of using flax for seals, two significant points are noted:
- The organic origin of flax fibers provokes their tendency to rot when combined warm water and air. Therefore, the use of flax requires the mandatory use related materials such as lithol, grease, oil paints. However, later these materials will prevent the dismantling of the joints, since they firmly glue the sealed parts to each other.
- Linen is very picky about following the rules of winding, a certain skill is required from a plumber to perform it.
Stuffing materials
Home plumber stuffing materials needed:
- for sealing shutoff valves in water supply systems;
- for sealing sockets of sewer and water pipes.
Gland packings
Stuffing box packings GOST 5152−77 “Stuffing boxes. Specifications” seal seals of fittings, pumps and other equipment operating in a wide range of pressures and temperatures of working media. For drinking water used stuffing HBS (braided cotton dry packing) TU 2572-141-00149363-99, which is an elastic cord of square or round section, woven from cotton threads. 
Resin strands and ropes
For sealing pipe sockets during the installation of sewerage or plumbing systems, resin strands of GOST 16183-77 “Impregnated tape tow. Specifications”, commonly called “kabolka”, and hemp ropes GOST 483−75 “Hemp ropes. Specifications". Impregnation of tow fibers and ropes with resin gives them biostability and resistance to decay, which increases their service life. 
Silicone sealants
Increasingly, sealants are used in plumbing work, which perfectly cope with leaks. Most suitable for use in living conditions is a liquid silicone rubber, called plumbing silicone sealant. Plumbing sealant for filling and sealing joints and connectors is a one-component composition, which is very technologically advanced in domestic use. 
Stuffing materials
To ensure the density of individual nodes of valves and various designs gland packings (GOST 5152-77) are used, designed for operation in a wide range of pressures and temperatures of water, steam, gases, combustible and aggressive media.
Depending on the working conditions, packings of 3 types are used: wicker, rolled and ring.
Braided stuffings are made of cotton, hemp, jute, linen, asbestos cords various weaving- with a core, reinforced or unreinforced, dry or impregnated with antifriction and other compounds (talc, graphite, rubber, fluoroplastic). They are designed for maximum temperature 100 ° C - 400 ° C, pressure 4.5-20 MPa and for use in the following environments: air, industrial and drinking water, salt solutions, water vapor, inert vapors and gases.
Rolled packings are made by rolling cords from cotton, rubberized, asbestos fabric. They are designed for a maximum temperature of 100 o C - 400 o C, pressure 10-20 MPa and application for industrial water and superheated and saturated steam.
Annular packings are solid-rolled or split multi-layer figured cross-section rings made of asbestos rubberized fabric, vulcanized and graphitized. They are designed for a temperature of 300 ° C, a pressure of 20 MPa, they are used for air, industrial water and steam.
Graphite (GOST 4596-75) - a steel-gray crystalline substance, soft and greasy to the touch, is produced in the form of finely ground powder and in the form of flakes. Flake graphite is used to impregnate gland packings and paronite gaskets. Graphite mixed with natural drying oil is called graphite paste. This paste is used to lubricate nipples and nipple sockets when assembling sectional cast iron boilers.
Lubricants, drying oils and paints
Lubricants are used to ensure normal operation, reduce friction and prevent wear of moving and rotating parts of sanitary equipment, instruments and fittings, in particular self-lubricating ones, as well as for temporary protection. metal surfaces from corrosion.
Lubricants are classified into lubricating oils ( liquid materials) and greases.
Lubricants and lubricating oils are available in universal and special purpose, while the scope and conditions of their application are regulated by the relevant standards and specifications.
Industrial (spindle) oil grades 12 and 20 according to GOST 20799-75 is used for lubricating the rubbing parts of mechanisms and wetting the filtering surfaces of oil filters. Compressor oil brand 12 (M) in accordance with GOST 1861-73 is used for lubricating parts of compressors and blowers. Viscinal and perfume oils are used to absorb dust in the filters of ventilation systems.
Greases (greases) are a thick ointment and are used in case of impossibility or difficulty in supplying liquid lubricant to lubricate components and parts. These lubricants are divided into three types: synthetic (from artificial fats), fatty (from natural vegetable and animal fats), emulsion (from oils mixed with rosin). Greases are used to lubricate ball and roller bearings, to protect against corrosion and to preserve machined metal surfaces. Grease grease brand US according to GOST 1033-73 is used for lubrication of fans and other mechanisms at a temperature of not more than 60 ° C. Graphite grease BVN-1 according to GOST 5656-60 is used to lubricate mating surfaces steel pipes subjected to temperature changes during operation. Technical vaseline and conservation lubricants K-17 are used to preserve and protect metal surfaces of sanitary equipment from corrosion.
The purpose of paints and varnishes is to protect products from corrosion and give them a decorative look.
The following requirements are imposed on paintwork materials: the ability to hold firmly on the surface of the product to be painted, the presence of the necessary mechanical strength, hardness and elasticity, resistance to water, oil products, sun rays, maintaining its qualities at low and high temperatures, water resistance, the ability to dry quickly and provide the desired color.
Depending on the purpose, paints and varnishes are divided into three groups: primers designed to provide a strong bond between the surface to be painted and paintwork; putties designed to level the surface to be painted; paints (varnishes, enamels) intended for the formation of the outer layer of the coating.
Primers are either specially manufactured compositions (suspensions of pigments, solvents and fillers), or a mixture of paint and drying oil. The primer is applied thin layer, therefore, its viscosity (thickness) should be significantly lower than the viscosity of the coating itself.
Putties are a thick liquid or paste, which is a mixture of primer, solvent, pigment and aggregate (chalk, gypsum, kaolin).
Paints are divided into oil paints, varnishes and enamels.
Oil paints are a paste consisting of a dye, a small amount of solvent and special impurities. Before use, oil paints must be diluted with drying oil or solvent. Varnishes are a solution of resin in oil or an easily evaporating solvent with the addition of special impurities. Enamels are finely ground dyes diluted on varnish.
Drying oil oksol (GOST 190-68) is a substitute for natural drying oil, made by compacting linseed oil with air blowing it in the presence of a desiccant and then adding a solvent (white spirit). It is used for thinning thick paints.
Primer GS-2020 (GOST 4056-63 *) is a suspension of pigments (red lead and zinc white) and filler (talc) in phthalic varnish with the addition of solvents, a desiccant and a stabilizer. Used for priming metal surfaces. The primer film is resistant to temperature changes from - 40 o C to + 60 o C. Drying time at a temperature of 100-110 o C is no more than 35 minutes, at a temperature of 18-23 o C - no more than 48 hours. It is applied with a paint sprayer, brush, dipping. In order to obtain a working viscosity, the primer is diluted with a solvent, xylene, or a mixture of one of these solvents with white spirit.
Dry iron minium (GOST 8135-74) is a natural mineral pigment, consisting mainly of iron oxide. Depending on the purpose, two grades are produced: A - for the manufacture of primers, enamels and oil paints; B - for the manufacture of adhesive paints, colored asbestos plywood and asbestos products.
Colored oil paints, thickly ground (GOST 8292-75) and special (GOST 18596-73) are a paste of a mixture of dry pigments and filler, rubbed on natural drying oil or its substitutes. They are used after dilution with drying oil to a working viscosity for coating the outer surfaces of products in order to protect them from corrosion and give them a distinctive color. These coatings are weather resistant. Applied by spray, brush, dipping, streaming or spraying in an electrostatic field. In the latter case, white spirit or turpentine is added to the paint. Drying of the paint at a temperature of 18-22 ° C is carried out within 24 hours, at a temperature of 100 ° C - within 2 hours.
Lacquer BT-577 and paint BT-177 are manufactured in accordance with GOST 5631-70*. Lacquer BT-577, which is a solution of black resins and vegetable oils in organic volatile solvents, used to coat metal surfaces, as well as in the manufacture of paint BT-177. The latter is a suspension of aluminum powder in BT-577 varnish.
It is prepared immediately before application to the surface by introducing 15-20% aluminum powder into the BT-577 varnish. The paint is designed for anti-corrosion and decorative coating metal surfaces to which it is applied using a paint sprayer. The time of practical drying at a temperature of 18-23 ° C varnish BT-577 24 hours, paint BT-177 - 16 hours, and at a temperature of 100 ° C, respectively, no more than 20 and 30 minutes. Lacquer coatings have reduced weather resistance, but are resistant to prolonged exposure to temperatures up to 20 ° C. The introduction of aluminum powder increases the weather resistance and heat resistance of the coating. In order to improve protective properties hot drying is recommended.
To dilute the drying oil, turpentine is used, to dilute the primer and oil paints - solvent, white spirit, xylene.
To degrease metal before coating with paintwork material, it is recommended to clean it with white spirit or a mixture of caustic soda with trisodium phosphate, liquid glass.
To cover the air ducts of ventilation systems operating in aggressive environments, perchlorvinyl enamels are used that are resistant to acid vapors, alkalis and other aggressive environments. Enamel grades are selected depending on the operating conditions of the air ducts.