The characteristics and usage of gate valve expansion joint

The characteristics and usage of gate valve expansion joint
Valve expansion joint working principle and use: the model of single flange limit expansion joint is: VSSJA-1 type or BF type, also called compensation joint, expansion joint, expansion joint, pipeline compensator, etc. The single flange limit expansion joint is a kind of loose-fitting expansion joint developed on the basis of the loose-fitting expansion joint. The connection method of the single flange limit expansion joint is flange connection on one side and welding on the other side, which should be noted during installation: the loose-fitting expansion joint is installed After being installed on the pipe, tighten the nut elastic seal, and rely on mutual slope under the action of the nut gland, tightly pressed on the outer ring of the pipe to seal and connect the role. When the temperature changes the pipe can be free to expand and contract in the middle of the joint, when the foundation sinks, the pipe can be deflected and ensure the seal without leakage, thus playing the purpose of automatic compensation.
The gate expansion joint is a limit device added on the basis of the original performance of the loose-fitting expansion joint, which is locked with double nuts at the expansion volume. The pipe can be freely expanded and contracted within the allowed expansion volume, and once the expansion volume exceeds the limit, it ensures the normal operation of the pipeline, which is especially suitable for the connection in pipelines with vibration or with certain slope and bend. Because of the good comprehensive performance of monoflange limit expansion joint, it is widely used in chemical industry, construction, water supply, drainage, petroleum, light and heavy industry, refrigeration, sanitation, plumbing, fire-fighting, electric power and other basic projects.
Notes for installation of gate valve expansion joint:
1 . The gate valve expansion joint should be checked for its type, specification and pipeline configuration before installation, which must meet the design requirements.
2 . For the gate valve expansion joint with inner sleeve, attention should be paid to make the direction of the inner sleeve consistent with the direction of media flow, and the hinge rotation plane of the hinge type expansion joint should be consistent with the displacement rotation plane.
3 . For the gate valve expansion joint that needs to be "cold tightened", the auxiliary components used for pre-deformation should be removed only after the pipeline is installed.
4 . It is strictly forbidden to use the method of deformation of the gate expansion joint to adjust the installation of the pipeline overrun, so as not to affect the normal function of the expander, reduce the service life and increase the load of the pipe system, equipment and supporting members.
5 . In the process of installation, the welding slag is not allowed to splash to the surface of the wave shell, and the wave shell is not allowed to be damaged by other mechanical damage.
6 . After the installation of the pipe system, the yellow auxiliary positioning components and fasteners used for the installation and transportation of the gate valve expansion joint should be removed as soon as possible, and the limit device should be adjusted to the specified position according to the design requirements, so that the pipe system has sufficient compensation capacity under environmental conditions.