What kind of pe crane is needed for underground installation. Underground ball valves Optimum storage tank material

For a water or gas pipeline, it is most convenient to embed an underground plastic ball valve. Such a design can provide a sufficiently long period of operation, moreover, without any problems with maintenance.

There are many material options for such valves, but plastic is the most convenient, as it is not at all afraid of dampness and corrosion. We'll show you how to install it and show you a themed video in this article.

PE taps

Description

• much cheaper than metal ones, so most settlements and various industrial facilities cannot do without communication routes made of this material. In addition, the price of a PE crane is much less than that of a steel counterpart, but the service life is immeasurably longer, which also plays an important role in the choice of materials for pipelines.
• The widespread use of such a mechanism is also due to its fairly wide range of diameters.- it can be mounted on pipes with a cross section of 20 to 315 mm and it can operate at temperatures from -20 ⁰C to +40 ⁰C, this is acceptable for any region of the Russian Federation for underground installation.

• In addition, a ball valve for underground installation can be mounted without equipping a special well for this - to adjust it, it is enough to bring the control mechanism outside, and the assembly itself can be covered with earth. The distance to the ground surface from the pipe can be from 1650 mm to 2750 mm.
• The telescopic rod is extended by a square hollow profile, at the end of which a hexagonal sleeve is welded, which is installed on the crane axis and rotated using a square / hexagonal metal rod.
• A ball underground valve is made of polymeric materials(the design is intended for butt welding, or for). The outlet pipes on this mechanism are made of PE 100 SDR11 - this is quite enough for gas pipelines with a pressure of 10 bar and water pipes with a pressure of 18 bar.

Note. A protective polyethylene casing of two thin-walled pipes is installed on the extension cord.
They can move freely from one to another.

Specifications of some cranes

Table for SDR11

Ball valves PE

Dimensions. Standard

PE faucet without blowdown

Installation nuances

Note. In the Russian Federation, at the moment, a water or gas underground tap is not widely used.
However, a lot of construction organizations are showing a healthy interest in such structural devices.

These shut-off valves in ground or underground (using wells) design can be used in gas facilities. But, at the same time, the instruction does not recommend the use of wells along the route.

The thing is that the rules for working in these tanks and recommendations for opening them greatly complicate the operation of this type of shut-off valves.

JSC "Gazprom" has developed certain technical standards, in which the installation of stop valves made of polyethylene (the price is not taken into account) is preferably carried out without wells.

Installation "under the hatch"

There is a standard STO GAZPROM 2-2.1-093-2006, which demonstrates (illustrate) solutions for the design, construction and reconstruction of polyethylene pipelines for gas pipelines.

It describes a variety of installation options for PE ball type valves that can be performed:

• Directly on the roadway (in the middle of the road);
• Directly on the carriageway (in the middle of the road) and on pedestrian sidewalks, as well as in the park area;
• Under the carpet (turf) in the park area or forest belt.

Conclusion

Do-it-yourself installation of PE taps for home plumbing is currently somewhat difficult, since there is no special equipment for this, which is supplied through a network of hardware stores.

If we talk about plastic, then for the private sector preference is given to polypropylene and at the moment this material fully satisfies the needs of residents of the private sector.

Underground plumbing

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Underground water pipes should be laid below the freezing depth of the soil. The depth of laying is also dictated by the need to protect pipes from dynamic loads created by moving vehicles.

To connect underground water pipes in Czechoslovakia, Wimer connections are used, and for glass concrete pipes, after putting on a rubber cuff, the joint is reinforced with a metal spiral and filled with cement mortar. For pipelines of large diameters, standard cast-iron plumbing parts are used instead of undeveloped glass fittings.

Galvanized pipes are often used for underground water pipes. In table. 7.4 shows the test results that were obtained on galvanized pipes and plates after testing in the ground in different places.

For firefighting, water is taken from an underground water supply system, natural or artificial reservoirs and is supplied to the fire site by fire trucks. In industrial premises, in niches of walls or cabinets, internal fire hydrants with one (or two) rubberized sleeve and barrel are installed in such a way that at least two jets of 2 5 l / s can be supplied to each industrial premises from two adjacent cranes.

Pig-iron pressure pipes are intended for underground water pipes and pressure sewer collectors; are made of gray cast iron by centrifugal and semi-continuous casting.

Reinforced concrete pipes are used for the construction of underground water pipelines, sewerage, sewerage collectors for cable laying.

The operational reliability of structures is at risk. This applies, for example, to underground water pipes, which can fail due to corrosion. Other examples would be electronic equipment where important control functions can be affected by corrosion; offshore oil platforms operating in extremely corrosive environments; nuclear power plants, where corrosion damage can lead to costly accidents, in some cases completely unacceptable from a safety point of view. Corrosion-induced production interruptions are becoming increasingly important to society as more and more complex designs are used.

The location of plastic pipes of gas pipelines underground is assigned by the project. The layout of the route of gas pipelines is carried out similarly to the layout of the route of underground water pipelines, described above. Earthworks for digging trenches are carried out by narrow trench excavators. On the soil-free side, plastic pipes prepared for installation are laid out.

In 2003, after field tests of a prototype of the MI-31 in-line magnetic introscope conducted on the basis of the MGP Mosvodokanal, it was concluded that the MI-31 design allows continuous monitoring of the entire length of the pipeline section with a resolution of 2 mm and a productivity of 0 5 m/s. The proposed technology makes it possible to detect both through and non-through defects in the wall of an underground water pipeline located on the inner and outer surface of the pipe, to determine their relative position and geometric dimensions without opening the pipeline route.

Hudson and Acoq [141] describe five years of testing of galvanized steel pipes at five different locations by BISRA. In all test sites, galvanized pipes showed slightly higher resistance to corrosion than steel pipes. Small diameter galvanized pipes are often used in underground plumbing on farms and in other similar applications.

In all industrialized countries, the problem of protecting metal from corrosion is becoming increasingly important. Among the various methods used to solve it, a special place is occupied by electrochemical (cathodic) protection systems, which are widely used to prevent the destruction of metal structures operated in natural waters and soils. The scope of cathodic protection is very wide; it covers underground water pipelines, gas, oil and product pipelines and metal pipelines for other purposes laid in the ground, underground communication cables, power cables with a metal sheath and armor, cables laid in pipes filled with compressed gas or oil, various storage tanks and cisterns, river and sea vessels, port equipment, potable water installations and various chemical industry apparatus requiring internal protection.

Separate data regarding the dimensions and weight of the pipes are given in table. 6.16. Pipes are supplied mainly in lengths of 5 m with smooth ends - the so-called industrial pipes. The pipes are connected using glued couplings or fittings. At the request of the customer, they are supplied at one end with a coupling connected to the pipe with glue. In underground water pipes, it is recommended to use rubber seals for contact connections.

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Ball valve polyethylene for underground installation brand DAEYOUN

Underground polyethylene ball valve is designed for installation on gas pipelines and water pipelines located underground, and acts as a locking mechanism. The working environment is controlled by opening or closing the stop valve valve.

Thanks to the auxiliary bearing, the ball moves smoothly after being installed in the ground.

These cranes have a full passage for passing the working medium through themselves. Valves over 200mm in diameter are equipped with a mechanical operator, which reduces torque and ensures smooth opening/closing.

The design of the valve is made of plastic material (PE 100), which provides the most maximum corrosion resistance, thereby extending the service life up to 50 years.

Unlike underground steel cranes, underground polyethylene cranes have a removable telescopic stem, which can vary from 1.2 m to 2.0 m.

Polyethylene ball valves can be manufactured with Du from 20 mm to 400 mm.

A polyethylene underground crane is attached to the pipeline by butt or electric welding, and has a strong, tight, impermeable working environment connection.

Two (and in the case of large diameter valves, three) O-rings installed between the bearing and the housing, especially the one located at the bottom of the bearing, uniquely increases the level of tightness.

The pin between the adapter and the bearing securely fixes the valve during its opening and closing.

The sealing ring installed between the adapter and the body prevents soil and dust from entering the inside of the valve. Polyethylene ball valves for underground installation may be installed on a gas pipeline with a pressure of not more than 10 bar, and a water supply system with a pressure of not more than 16 bar, and in the temperature range from -29ºС to 60ºС.

To facilitate the rotation of the shut-off element in valves with a large diameter, one-way and two-way purges can be used.

Polyethylene ball valve without extension rod.

The crane is spherical polyethylene extended, for underground installation.

Polyethylene ball valve for underground installation, with one-way purge system.

Polyethylene ball valve for underground installation, with a two-way purge system.

Material and properties of parts:

Material: HDPE polyethylene - low pressure polyethylene (high density)

Characteristic: the body is designed taking into account the installation of the ball inside, the tightness and tightness of the bearing fixation, the ball seat, the retainer, the sealing rings. For easy installation, the bottom of the case is machined tightly. The bearing and adapter are located in the center of the bottom. The inside of the case is machined cleanly and neatly by CNC machines to securely install each part.

2. Bells

Material: Polyethylene (MDPE: Medium Density Polyethylene)

Characteristic: sockets are made taking into account the connection with a specific pipe. It is made with grooves for inserting heat pipes. At the choice of the client, installation for a crane of any type is possible (without purge, with one, two purges).

Material: polypropylene (POLYPROPYLENE: PP)

Feature: The ball is made by CNC machine. The ovality of the ball does not exceed 30㎛, so there is no damage to the seat from friction. The applied silicone grease allows operation even with minimal torque.

4. Bearing

Material: acetal (ACETAL)

Feature: bearings are made of acetal parts molded from extruded blanks by digital control, taking into account stability, elongation, dimensional stability. Increased tightness thanks to 3 O-rings - between the middle of the stem and the body (2 pcs.) and between the lower part of the stem and the body (1 pc.).

5. Ball seat

Material: NBR (RUBBER)

Feature: Ball seat, O-ring, and other rubber parts are made of Nitrile Butadiene Rubber (NBR) to improve elasticity, elongation, and durability under standard temperature and pressure ranges.

6. Retainer

Material: polypropylene (POLYPROPLENE)

Feature: These elastic retainers are injection molded from polypropylene and are inserted on both sides of the body and hold the ball seat firmly.

7. Adapter

Material: polypropylene(POLYPROPLENE)

Feature: Made of polypropylene by injection molding, taking into account the large load when the ball is fired, including tensile force, elongation, impact resistance. At the bottom of the adapter there is a locking device that prevents rotation more than 90°. A sealing ring is inserted inside the adapter, with the help of which it is possible to prevent the ingress of foreign particles. The adapter is able to withstand a large load.

8. Auxiliary rod

Material: acetal (ACETAL)

Feature: Provides simple, easy operation even when the crane is buried deep in the ground. Designed to take into account the high load that occurs at the bottom of the stem when the ball is fired (which even exceeds the load at the top!). The lower part is injection molded from acetal and can withstand the highest excess torque when opening/closing the valve.

9. Mechanical operator

Material: polyethylene, etc.

Feature: designed for large diameter valves (more than 200mm), mounted on the auxiliary stem with 4 gearboxes to reduce torque. Resistant and anti-corrosion. Handwheel opens/closes easily with 2½ turns. The mechanism is equipped with a safety device to prevent unnecessary stress when the opening/closing is completed (internal parts can be replaced if they break).

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location options and installation rules

The organization of an autonomous water supply system in a suburban area provides an opportunity to enjoy the benefits of civilization, regardless of the presence of centralized communications. Most often, in personal baths, a cold water supply system is arranged from a well or a well, and a storage tank is used to provide water pressure. It is also required to collect a reserve supply of water in case of power outages. Where is it better to place a storage tank for cold water so that the bath water supply system works properly and does not create problems for the owners.

Storage tank in autonomous water supply

An individual water supply system with a storage tank is extremely simple. Water from a well or well is pumped by a pump, the type of which depends on the height of the water level in the source. Mostly in suburban farms, quiet submersible pumps or stations with an ejector and their own hydraulic tank are used.

The pumping station is good if the suburban building has its own basement. Or there is enough space on the site for the construction of a change house for its placement, tk. this is quite a "sounding" equipment. But buying a station can save you from installing a storage tank if its built-in tank differs in volume sufficient for daily consumption.

Unattractive in terms of sound interference and surface pumps, but they are significantly cheaper. True, they pump water only from wells and wells with a high water table or from nearby lakes, ponds, rivers. For surface pumps, the main thing is that the height difference between the point of water intake from the source and the point of delivery to the storage tank does not exceed 6-7m, which is extremely rare in reality.

Due to the inclusion of a storage tank in the scheme of an autonomous water supply system, the water pumped out by the pump does not immediately enter the taps, the tank on the sauna stove, the boiler, the shower, the toilet bowl and other water points. First, water accumulates in the form of a reserve approximately equal to the volume of the reservoir. The water reserve in the storage tank makes it possible to use several plumbing fixtures at the same time. Without a supply of water, normal pressure for use would be in only one open tap, and that is not a fact.

In an autonomous water supply system, the cold water storage tank, in theory, performs the function of a water tower. The supply of water also allows you to reasonably limit the number of pump on / off, which is extremely beneficial for any technique. The storage tank is equipped with a mechanical, electronic or electric float valve so that the pumping equipment does not work in vain, because:

• when the water pumped into the tank reaches the limit level, the float signals that the pump is turned off;
• when the level drops, a command is given to turn on the pump to replenish the spent stock.

This eliminates unnecessary work of equipment and overflows. Instead of a valve, craftsmen contrived to use the toilet's float mechanism, which simply closes the hole for water to enter when the required volume is exceeded. The pump can be turned on/off manually or automatically. You will also need a “dry running” relay to stop the pump if the storage tank is completely empty.

There are holes in the cold water storage tank that are required to connect the pipeline and to ensure the normal operation of the system as a whole, these are:

• hole for connecting the supply pipe. Before entering the supply pipe, it is recommended to install a coarse mesh filter in order to mechanically prevent small animals and large grains of sand from entering the tank;
• a hole for the overflow pipe, through which excess water is discharged from the tank into the sewer. They arrange an overflow a couple of cm below the float valve in case the latter does not work for some reason;
• one or more openings for outgoing pipes supplying the water heater and cold water draw-off points. Often they are located in the lower third of the tank, but there must be at least 10 cm between the bottom of the tank and the output points so that the sediment inevitable for groundwater does not enter the line;
• a ventilation hole in the cover of the drive, if the cover closes it from penetration into the container of dust, insects and other contaminants.

A hole for entering the supply pipe is sometimes arranged in the upper part of the tank opposite the place where the float valve is installed. However, in order to completely drain the water from the reservoir in order to preserve the autonomous water supply, it is recommended that the inlet pipe opening be located in the lower zone of the reservoir. It still needs to be equipped with a drain valve. If the lower location of the inlet of the supply pipe cannot be used for some technical reasons, then an additional drain hole will be required to preserve the water supply with a storage tank.

Methods for installing storage tanks

The type of water distribution and the set of equipment required for the trouble-free operation of the bath's cold water supply system depend on the location of the reserve tank. In low-rise construction, two main options for the construction of water pipelines with storage are used, these are:

• the upper diagram, according to which the reserve tank is installed on the highest possible platform: on a flat roof, on a specially erected overpass, on brackets under the ceiling, on a concrete podium inside or outside the building, attic, etc. The installation height of the storage tank in the upper diagram is a parameter taken according to individual technical conditions. Accumulators of year-round water pipes are necessarily insulated if they were installed in an unheated room;
• the lower scheme, according to which the cold water tank is buried in the ground in the basement of the building or on the site, if water is supposed to be taken from the tank for irrigation and other household needs. For a year-round water supply device, the storage tank is buried below the freezing zone; for a summer water supply, it is enough to position the tank so that there is at least 0.5 m between its upper plane and the earth's surface. A lower entry of the incoming pipe should also be provided and a drain device should be installed on it.

Often, independent home craftsmen prefer the upper scheme. It is easier to build a water supply system with an upper storage tank with your own hands, and it will not require less expenses than an underground one. Water is distributed by gravity to the water points without additional devices stimulating its movement. The only disadvantage of the upper scheme is a rather weak pressure, depending on the installation height of the storage tank. To create a pressure of 0.1 atmosphere, the tank will need to be raised by 1 m, for 0.5 atm. by 5 m. Do not forget that for the operation of a washing machine, for example, you need a water column pressure of 1 atm.

A water supply system with a lower storage location is sometimes referred to as a system with pneumatic capabilities. The pump pumps water into the underground tank, which compresses the air cushion there. When the water in the tank reaches a certain level, compressed air will begin to push it up to the water points. True, the pneumatic abilities of water pipes with lower wiring are rarely relied upon. They are too small. Most often, to supply water with a stable pressure from the lower storage tank, an additional submersible drainage-type pump installed directly into the tank with a float signaling device is used.

Optimum storage tank material

The volume of the storage tank should be equal to the one-time water consumption. In this aspect, everyone's preferences are different. Therefore, the acceptable capacity of the tanks ranges from 100 to 1000 liters. Requirements for storage tanks for cold water supply determine the upcoming operating conditions. In any case, the container must be airtight, wear-resistant, stable, and inert to chemical and biological contaminants.

As a storage device in the organization of autonomous water supply, you can use:

• a home-made welded tank with or without a lid, if the quality of the water is not too worrying for the owners of the summer cottage;
• factory opaque plastic container, instead of which it is quite acceptable to use eurocubes connected by pipes;
• a concrete cavity poured into an underground or above-ground formwork.

With your own hands, the tank can be welded from sheet steel, aluminum, from cutting a large diameter pipe. A metal barrel or an old bath with well-preserved enamel will be a budget alternative if you plan to organize a temporary summer water supply system with an upper storage tank. For it, you still need to make a cover with a vent.

The drive material is selected based on the place of its installation:

• in the upper scheme, a ready-made plastic tank or a metal container of our own manufacture can be used. The structure, on which the drive will be installed, must first be strengthened, because it will have to carry from 100 to 1000 kg of additional weight. If the tank is located outside, it must be carefully attached to the overpass so that after draining the water, the empty tank is not turned over by the wind;
• in the lower scheme of bath water supply with a storage tank, the best choice would be a ready-made container made of food-grade plastic or eurocubes. A tank with concrete walls is perfect, which can also serve as a protective “shell” for a plastic tank. Concrete protection will protect an empty or half-empty plastic product from ground pressure. Those. two in one is the perfect choice.

If the owners of a stationary bath water supply with a lower storage tank leave their beloved estate for several days in winter, the water from the underground reservoir can not be drained. It will not bloom because its environment resembles a thermos, and it will not freeze because the tank is below the freezing horizon. But cleaning an underground tank can create problems if the tank is not equipped with a maintenance hatch and the inlet pipe is not connected at the level of the bottom of the tank.

Membrane accumulator instead of storage

A hydraulic accumulator with a membrane is a high-tech descendant of conventional accumulators. His cost is not very humane, but he solves all issues with supply, water supply and pressure provision on his own. The membrane tank is a metal container, divided inside into two parts by an elastic bag-like partition-membrane. Air or nitrogen is pumped into one of the parts of the tank. Traditionally, a gaseous medium has a pressure of 2 atmospheres, but it can be adjusted.

When the pump is running, water fills the second part of the tank, stretches the membrane and compresses the gaseous medium, which, when the tap is opened, pushes water to the points of consumption. The hydraulic accumulator filled according to the specified parameters automatically turns off the pump. When the tank is empty and the pressure in the tank is reduced, the automation turns on the pumping equipment again.

The membrane tank is mounted in front of the branching of the pipeline. It can be installed in the caisson of the well, in the pit of the well or directly in the bath. There must be a check valve at the inlet to the tank to prevent the pumped water from flowing back into the source, and a pressure gauge at the outlet to check the pressure. To remove air from the system, the accumulator is equipped with an automatic valve. The membrane tank works in dynamic mode, so you can not get carried away with too large internal volumes.

A membrane-type hydraulic tank is a very useful thing in the household, but not cheap. You should not take on its installation and configuration without having experience in this matter. Incorrect pressure setting may cause diaphragm rupture. The fastening of the device vibrating in operation must be very reliable. Without knowledge of the technological intricacies of connecting, the tank will disturb with a rather unpleasant sound. But the hand-made installation of a conventional storage tank for supplying water to the bath is highly recommended and economically justified.

How to install a simple top drive

Let's analyze a common option with the location of the drive in the attic. So, we do it ourselves or choose a container that can climb into the attic hatch or window. Restrictions on volume and dimensions are not terrible for those who, while still in the process of construction, thought out a scheme for constructing a water supply system. Then the container can be pre-installed on the upper floor, if it does not interfere with the construction of the truss system.

Now we will analyze in detail how to install and connect a cold water tank to a year-round bath:

• pre-strengthen the base by laying thick boards on the beams of the upper floor;
• install the container in its place;
• install the float valve. To do this, we mark a point, departing from the upper edge of the container 7-7.5 cm, and cut out a hole of the size we need. We insert the valve shank into the formed hole, after putting a plastic washer on it. On the other side of the tank wall, we first put on a stiffening plate, then a second washer and screw on the nut. We tighten the fasteners and screw the connector to the shank so that the supply pipe can be connected;
• we drill holes for outgoing pipes according to their dimensions. From the inside of the tank, we insert a connector with a plastic washer into each hole. We strengthen the thread by screwing two or three layers of FUM tape, after which we put on the washer and wind the nut;
• we cut a shut-off valve into each outgoing pipe;
• we make an overflow, for which we mark a point 2-2.5 cm below the marking point of the float valve and drill a hole. The overflow pipe is discharged into the sewer, we fasten it to the tank with connectors by analogy with the previous one;
• we bring pipes to the tank and fix them by the compression method. We attach the newly created sections of the pipeline to walls or beams;
• we fill the storage tank with water in order to check the tightness of the connections, at the same time we adjust the position of the float in accordance with the position of the overflow;
• we insulate the container by attaching long pieces of polystyrene around to the walls or wrapping it with mineral wool.

Video instruction for installing an underground storage

In such a democratic way, you can organize cold water supply with a storage tank for a bathhouse. In fact, these are general recommendations - a kind of information for reflection, which should be adjusted according to the technical features of the structure.

Ball valves are a type of valves for pipelines that are designed for gaseous and liquid media. They are used in both domestic and industrial environments. Cranes are so widely used due to their reliability, durability and simplicity of design.

Distinctive features

Ball valves are compact, practical, neat and aesthetic appearance. Using them is incredibly simple: just turn the special knob 90 degrees. So you can instantly stop the supply of water or gas. This factor is especially important when it comes to any accidents and leaks in gas or water pipes.

It is also important that the faucet is made of durable material that is resistant to corrosion, mechanical damage and aggressive environments. In addition, the valves are wear-resistant and have a long service life. If necessary, they can be easily repaired at no tangible cost.

Design

Cranes consist of the following elements:

• frame;
• pens;
• housing and adjusting nut;
• Teflon sealing seat;
• stem with rubber seal;
• sealing washer.

The passage of the necessary medium is carried out by a special shutter - a part in the form of a metal ball with a through cylindrical hole in the middle. The size of this hole matches the inner diameter of the attached pipe. In this regard, the cranes are called full bore.

Operating a ball valve is extremely simple. If you open it completely, there will be almost no hydraulic losses in the circulation flow. This feature reduces the degree of wear of the pipes and increases their service life. To completely shut off the flow, simply turn the control knob 90 degrees.

Kinds

Throughput:

• full bore - 90-100%;
• incomplete bore - 40-50%;
• standard - 70-80%.

According to the material of manufacture:

• brass;
• plastic;
• other alloys.

Each material has certain advantages and disadvantages. The choice of a particular type depends on the purpose of the crane.

Mounting type:

• coupling;
• flanged;
• welded;
• combined.

Scope of application

Coupling

They are used to equip gas, water and heating systems of residential buildings and public buildings. Most often used for standard radiators, even under the carpet. Union valves are convenient and easy to use, practical, compact, easy and quick to install without special equipment. Suitable for pipes with a diametrical section of not more than 40 millimeters. If the pipe is larger, it is better to opt for a flanged valve.

Flanged

Mounted on pipes with a diameter of more than 5 centimeters. To achieve maximum tightness, special seals are used during their installation. This type of spherical structures is characterized by increased strength indicators. They are collapsible non-collapsible. In the first case, the design consists of two elements (to ensure easy and quick disassembly). This is necessary in order to easily replace a faulty structural part. Non-separable flange options have an integral body, and in case of damage to any part, the valve must be completely replaced.

Welded

Most often, such ball valves are mounted in closed places and cannot be dismantled. For example, they are often used in the construction of buildings. This is the main difference between the welded type and all the others. The structure is created by welding.

Combined

They include several options for attaching to pipes. The number of nozzles for combined cranes is different, in connection with this they are: through passage, angle, multi-way. The latter option is simply indispensable in situations where there is a need to mix several different media at the same time.

There is another, much less common type of ball valves - choke. It is used in various industries: chemical, food, etc. The main feature of such structures is the possibility of multiple dismantling. They are simple to implement and convenient to use.

The choice of a ball valve directly depends on what it will be used for and how it will be attached.

• If you are looking for a ball valve that is strong and durable that is resistant to corrosion and temperature changes, then it is better to opt for a brass construction. This option is ideal for hot water pipes or for the construction of underground structures.
• A plastic or polyethylene ball valve can easily deform or become unusable when exposed to high temperatures. Therefore, it is best used for pipes with cold water or gas.

When installing a ball valve underground, it is not necessary to build a special well - for adjustment, it is enough just to remove the control mechanism and cover the assembly with earth.

How the ball valve works, see the following video.

In the underground version, it is designed for installation on gas pipelines and water pipelines located underground, and acts as a locking mechanism.
The working environment is controlled by opening or closing the stop valve valve.

Thanks to the auxiliary bearing, the ball moves smoothly after being installed in the ground.

These cranes have a full passage for passing the working medium through themselves. Valves over 200mm in diameter are equipped with a mechanical operator, which reduces torque and ensures smooth opening/closing.

The design of the valve is made of plastic material (PE 100), which provides the most maximum corrosion resistance, thereby extending the service life up to 50 years.

Unlike underground steel cranes, underground polyethylene cranes have a removable telescopic stem, which can vary from 1.2 m to 2.0 m.

Polyethylene ball valves can be manufactured with Du from 20 mm to 400 mm.

A polyethylene underground crane is attached to the pipeline by butt or electric welding, and has a strong, tight, impermeable working environment connection.

Two (and in the case of large diameter valves, three) O-rings installed between the bearing and the housing, especially the one located at the bottom of the bearing, uniquely increases the level of tightness.

The pin between the adapter and the bearing securely fixes the valve during its opening and closing.

The sealing ring installed between the adapter and the body prevents soil and dust from entering the inside of the valve.
Polyethylene ball valves for underground installation may be installed on a gas pipeline with a pressure of not more than 10 bar, and a water supply system with a pressure of not more than 16 bar, and in the temperature range from -29ºС to 60ºС.

To facilitate the rotation of the shut-off element in valves with a large diameter, one-way and two-way purges can be used.

Material and properties of parts:

1. Housing

Material: HDPE polyethylene - low pressure polyethylene (high density)

Characteristic: the housing is designed taking into account the installation of the ball inside, the tightness and tightness of the bearing, the ball seat, the retainer, the sealing rings. For easy installation, the bottom of the case is machined tightly. The bearing and adapter are located in the center of the bottom. The inside of the case is machined cleanly and neatly by CNC machines to securely install each part.

2. Bells

Material: Polyethylene(MDPE: Medium Density Polyethylene)

Characteristic: sockets are made taking into account the connection with a specific pipe. It is made with grooves for inserting heat pipes. At the choice of the client, installation for a crane of any type is possible (without purge, with one, two purges).

3. Ball

Material: polypropylene (POLYPROPYLENE: PP)

Characteristic A: The ball is made by CNC machine. The ovality of the ball does not exceed 30㎛, so there is no damage to the seat from friction. The applied silicone grease allows operation even with minimal torque.

4. Bearing

Material: acetal (ACETAL)

Characteristic: Bearings are made of acetal parts, molded from extruded blanks by digital control, taking into account stability, elongation, dimensional stability. Increased tightness thanks to 3 O-rings - between the middle of the stem and the body (2 pcs.) and between the lower part of the stem and the body (1 pc.).

5. Ball seat

Material: NBR (RUBBER)

Characteristic: Ball seat, o-ring, and other rubber parts are made of Nitrile Butadiene Rubber (NBR) to improve elasticity, elongation, and durability under standard temperature and pressure ranges.

6. Retainer

Material: polypropylene (POLYPROPLENE)

Characteristic: These elastic retainers are injection molded from polypropylene and are inserted on both sides of the body and hold the ball seat firmly.

7. Adapter

Material: polypropylene(POLYPROPLENE)

Characteristic: Made of polypropylene by injection molding, taking into account the heavy load when the ball is fired, including tensile force, elongation, impact resistance. At the bottom of the adapter there is a locking device that prevents rotation more than 90°. A sealing ring is inserted inside the adapter, with the help of which it is possible to prevent the ingress of foreign particles.
The adapter is able to withstand a large load.

8. Auxiliary rod

Material: acetal (ACETAL)

Characteristic: Provides simple, easy operation even when the crane is buried deep in the ground. Designed to take into account the high load that occurs at the bottom of the stem when the ball is fired (which even exceeds the load at the top!). The lower part is injection molded from acetal and can withstand the highest excess torque when opening/closing the valve.

9. Mechanical operator

Material: polyethylene, etc.

Characteristic: Designed for large diameter valves (more than 200mm), installed on the auxiliary stem with 4 gearboxes to reduce torque. Resistant and anti-corrosion. Handwheel opens/closes easily with 2½ turns. The mechanism is equipped with a safety device to prevent unnecessary stress when the opening/closing is completed (internal parts can be replaced if they break).