In the underground version, it is designed for installation on gas and water pipelines located underground, and acts as a locking mechanism.
The working environment is controlled by opening or closing the shut-off valve.
Thanks to the auxiliary bearing, the ball moves smoothly after being installed in the ground.
These taps have a full passage of the working medium passing through them. For taps with a diameter over 200 mm, a mechanical operator is installed, which reduces the torque and ensures smooth opening/closing.
The crane structure is made of plastic material (PE 100), which ensures maximum corrosion resistance, thereby extending the service life to 50 years.
Unlike underground steel cranes, underground polyethylene cranes have a removable telescopic rod, which can vary from 1.2 m to 2.0 m.
Polyethylene ball valves can be manufactured with diameters from 20 mm to 400 mm.
Attaches polyethylene underground crane to the pipeline by butt or electric welding, and has a durable, sealed connection that does not allow the working environment to pass through.
Two (and in the case of large diameter valves, three) sealing rings installed between the bearing and the housing, especially which is located at the bottom of the bearing, uniquely increases the level of tightness.
The pin between the adapter and the bearing securely fixes the tap during opening and closing.
The sealing ring installed between the adapter and the body prevents soil and dust from entering the tap.
Polyethylene ball valves for underground installation can be installed on a gas pipeline with a pressure of no more than 10 bar, and a water supply with a pressure of no more than 16 bar, and in the temperature range from -29ºС to 60ºС.
To facilitate the rotation of the shut-off element in large-diameter taps, one-way and two-way blowdowns can be used.
Material and properties of parts:
1. Body
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, ball seat, retainer, and O-rings. The bottom of the housing is machined tightly for easy installation. The bearing and adapter are located in the center of the bottom. The interior of the case is machined cleanly and accurately using CNC machines to ensure each part fits securely.
2. Bells
Material: polyethylene(MDPE: medium density polyethylene)
Characteristic: Sockets are made to fit a specific pipe connection. Manufactured with grooves for inserting heat conductors. At the customer's choice, it is possible to install it for any type of tap (without blowing, with one, two blows).
3. Ball
Material: polypropylene (POLYPROPYLENE: PP)
Characteristic: The ball is made using a CNC machine. The ovality of the ball does not exceed 30㎛, due to which there is no damage to the seat due to friction. Inflicted Silicone Grease, allows work even with minimal torque.
4. Bearing
Material: acetal (ACETAL)
Characteristic: Bearings are made from acetal parts, digitally molded from extruded blanks taking into account stability, elongation, and dimensional stability. Increased tightness thanks to 3 O-rings - between the middle of the rod and the body (2 pcs.) and between the lower part of the rod 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, durability under standard temperature and pressure ranges.
6. Lock
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 released, including tensile force, elongation, impact resistance. There is a locking device at the bottom of the adapter that prevents rotation beyond 90°. An O-ring is inserted inside the adapter, with which it is possible to prevent the entry of foreign particles.
The adapter can withstand heavy loads.
8. Auxiliary rod
Material: acetal (ACETAL)
Characteristic: Provides simple, easy operation even when the valve is buried deep in the ground. Designed to withstand the heavy load that occurs at the bottom of the stem when the ball is released (which even exceeds the load at the top!). The lower part is made of acetal by injection molding and withstands the greatest excess torque when opening/closing the tap.
9. Mechanical operator
Material: polyethylene, etc.
Characteristic: designed for taps large diameter(more than 200mm), installed on an auxiliary rod with 4 gearboxes to reduce torque. Resistant and anti-corrosion. The flywheel opens/closes easily with 2½ turns. The mechanism is equipped safety device to prevent unnecessary stress when completing opening/closing (internal parts can be replaced if they break).
For a water supply or gas pipeline, it is most convenient to embed an underground ball valve made of plastic. This design can provide a fairly long period of operation, and without any problems with maintenance.
There are many options for materials for such shut-off valves, but plastic is the most convenient, as it is not at all afraid of dampness and corrosion. We will tell you how to install it and demonstrate a thematic 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 tap is much lower than that of a steel analogue, but its 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 from 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 constructing a special well for this purpose - to adjust it, it is enough to remove the control mechanism outside, and the assembly itself can be covered with earth. The distance to the ground surface from the pipe can range from 1650 mm to 2750 mm.
- The telescope rod is extended due to the square hollow profile, at the end of which a hexagonal bushing is welded, which is installed on the axis of the crane and rotates using a square/hexagonal metal rod.
- An underground ball valve is made from polymer 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 pipelines with a pressure of 18 bar.
Note. A protective polyethylene casing made of two thin-walled pipes is installed on the extension cord.
They can move freely one into another.
Technical characteristics of some cranes
Table for SDR11
Ball Valves PE
| Diameter (mm) | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 | 20 | 0,560 |
| Weight (kg) | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 | 25 | 0,560 |
Dimensions. Standard
PE valve without purge
Installation nuances
Note. IN Russian Federation At the moment, the water or gas underground tap is not widely used.
However, a lot construction organizations show a healthy interest in such structural devices.
These shut-off valves in above-ground or underground (using wells) versions can be used in the gas industry. But at the same time, the instructions do not recommend using wells along the route.
The thing is that the rules for working in these tanks and recommendations for opening them significantly complicate the operation of shut-off valves of this type.
OJSC Gazprom has developed certain technical standards in which the installation of shut-off valves made of polyethylene (the price is not taken into account) is preferably carried out without wells.
Under-hatch installation
There is a standard STO GAZPROM 2-2.1-093-2006, which demonstrates (illustrates) solutions for design, construction and reconstruction polyethylene pipelines for gas lines.
The most various options installation of PE taps ball type which can be done:
- Directly on the roadway (in the middle of the road);
- Directly on the roadway (in the middle of the road) and on pedestrian sidewalks, as well as in the park area;
- Under a carpet (turf) in a 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 private sector residents.
Ball valves are a type of pipeline shut-off valves that are designed for gaseous and liquid media. They are used in both household and industrial conditions. Cranes have become so widespread due to their reliability, durability and simplicity of design.
Distinctive features
Ball valves are compact, practical, neat and aesthetic appearance. They are incredibly easy to use: just turn the special handle 90 degrees. This way 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 pipelines.
It is also important that the tap is made of durable material that is resistant to corrosion, mechanical damage and exposure to aggressive environments. In addition, the taps are wear-resistant and have a long service life. If necessary, they can be easily repaired without significant costs.
Design
The taps consist of the following elements:
- frame;
- pens;
- housing and adjusting nut;
- Teflon sealing seat;
- rod with rubber seal;
- sealing washer.
Passage necessary environment is carried out due to 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 is the same as internal diameter connected pipe. In this regard, the valves are called full bore.
Operating the ball valve is extremely simple. If you open it completely, there will be almost no hydraulic losses in the circulation flow. This feature reduces pipe wear and increases their service life. To completely block the flow, simply turn the control knob 90 degrees.
Kinds
By throughput:
- full bore – 90–100%;
- partial 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 specific type depends on the purpose of the crane.
By type of fastening:
- coupling;
- flanged;
- welded;
- combined.
Scope of application
Coupling
Used to equip gas, water and heating systems residential buildings And public buildings. Most often used for standard radiators, even under carpet. Union valves convenient and easy to use, practical, compact, easy and quick to install without special equipment. Suitable for pipes with a diametrical cross-section of no 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 over 5 centimeters. To achieve maximum tightness, special seals are used during their installation. This type spherical structures are distinguished by increased strength indicators. They are either collapsible or non-dismountable. 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 flanged options have an integral body, and if any part is damaged, 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 others. The structure is created by welding.
Combined
They imply several options for attaching to pipes. The number of branch pipes for combined valves is different; therefore, they are: through, angular, multi-way. The latter option is simply irreplaceable in situations where there is a need to simultaneously mix several different environments.
There is another, much less common type of ball valve - union valve. It is used in various industries: chemical, food, etc. Main feature Such structures are capable of repeated dismantling. They are simple to implement and easy to use.
The choice of a ball valve directly depends on what it will be used for and how it will be mounted.
- If you need a strong and durable ball valve that is resistant to corrosion and temperature changes, then it is better to opt for a brass design. This option is ideal for hot water pipes or for the construction of underground structures.
- A plastic or polyethylene ball valve can easily become deformed 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, you do not need to build a special well - to adjust, you just need to remove the control mechanism and fill the assembly with soil.
To see how a ball valve works, see the following video.