Ball valve for welding: design and application

Ball valves act as stop valves onexternal pipelines (gas and oil pipelines, pipelines of utility lines, pipelines in chemical explosive and fire hazardous industries, etc.). One of the varieties of the ball valve is a ball valve for welding.

It is used as a locking device forIn order to completely block the flow of circulating medium in the pipeline. Such an environment can be oil and its products, water, natural gas, air, alcohol products, other aggressive media.

This type of crane is characterized by the fact that itsconnect with the pipeline by welding. The ball valve for welding does not have detachable parts (flanges, couplings, etc.), and this ensures maximum connection density and minimization of leaks in joints.

Classification

Ball valves for welding are classified according to the type of drive:

• manual;
• having electric drive (manufactured by special order taking into account the features of the pipeline);
• manual with a reducer;
• with a pneumatic drive (manufactured by special order, taking into account the features of the pipeline).

Usually a hand welded ball valveThey are used with relatively small overall dimensions of the passages, with low or medium pressure in the pipeline. If the pipeline pressure is above average, and the pipes themselves are large or medium-sized, it is better to use a crane with electric drive or a crane with pneumatic drive.

Also, the ball valve for welding can be full-bore and incomplete (classified by the type of passage).

Production and construction of a ball valve

The components of the body of ball valves are made by welding (so that the connection is strong and reliable). The free-floating ball is sealed with PTFE seats.

In production, the originaltechnology. The principal feature of the devices is a steel, non-separable casing. During production, the locking mechanism is first assembled, and then inserted into the housing. The nipples are gently scalded.

The result is a non-separable design that does not need maintenance.

Кран шаровой стальной под приварку имеет unique internal design. In case of wear, this design compensates for the process itself. This is facilitated by free-floating balls, which are located between the springs having a seal. If one part wears out, then the spring opens up and the design is still tightly connected. It provides tightness for a long time.

Operation and maintenance

1. The ball valve for welding should be operated at a temperature of at least 30 ^aboutFROM.

2. The pressure in the pipeline can be 1.6 / 2.5 / 4 megapascals.

3. The circulating medium must also be of appropriate temperature: range from -35 to +180 ^aboutFROM.

Regular care and costly technicalmaintenance of these devices is not needed. Yourself, you can add only the seal on the stock. Design development does not provide for repair work or replacement of parts during the entire period of use.

Advantages and disadvantages of ball valves for welding

Pluses:

• low specific weight;
• low cost;
• the tap opens easily and quickly;
• when using the crane, no stagnant zones are formed in the area where the fluid flows;
• robust, reliable and simple construction;
• hermetic shut off of the fluid flow;
• This crane is installed in the most critical and difficult to access areas of the pipeline;
• no maintenance required.

Disadvantages:

• repair is impossible;
• it is possible to install and change the crane only with welding;
• the possibility of water hammer with a sharp opening of the crane;
• inconvenience when using because of the long lever of overlapping of the crane (during the work in close conditions).