1、 Overview of pneumatic ball valve: pneumatic ball valve is a ball valve equipped with a pneumatic actuator. The pneumatic actuator has a relatively fast execution speed, with the fastest switching speed of 0.05 seconds per time, so it is usually called pneumatic quick cut-off ball valve. Pneumatic ball valves are usually equipped with various accessories, such as solenoid valves, air source processing triplets, limit switches, positioners, control boxes, etc., to achieve local control and remote centralized control. The valve can be opened and closed in the control room without the need to run to the site or high altitude and dangerous areas for manual control, which greatly saves human resources, time and safety

How to install plastic coated pneumatic butterfly valve correctly
The plastic coated pneumatic butterfly valve may be in the normal straight state when it is used, or in the true bending state, or it is more complicated according to the construction requirements, so that the correct device can be installed under this condition
When plastic coated pneumatic butterfly valve is used, it may be in a normal straight state, it may be in a true bending state, or it may be more complicated according to the construction demand. Under such a situation, how can we correctly install the device, and what matters need to be paid attention to so as not to present the device errors, for the convenience of everyone's construction, We summarized the following points on the correct device of plastic coated pneumatic butterfly valve!
1： Attention to the bending radius of plastic coated pneumatic butterfly valve The bending radius of plastic coated pneumatic butterfly valve is strict and regular, because when the bending radius is (5-10) d, the wave shape mainly depends on the change of wave trough and flange radius. When the bending radius is small (5-10) d, residual deformation will occur not only in the wave pattern of the corrugated bending section, but also in the wave pattern of the straight section. Under this condition, the hose is destroyed after several deformation cycles.
2： The influence of the installation status of the plastic coated hose on the laying of pneumatic butterfly valves may be installed in the straight state or in the bending state. No matter what kind of pneumatic butterfly valve device diagram is used for the length of pneumatic butterfly valve used for equipment, the middle section H should be regular, and its value is H=(2~3) d. It is used to avoid excessive deformation and easy destruction of flexible parts at embedded joints. Due to the maximum load on the ripple directly near the embedded part of the joint, and the residual thermal stress caused by welding or brazing end joints, the fatigue strength of the embedded part is reduced. It is here that the pneumatic butterfly valve is most often damaged.
3： Stress relief during plastic coated hose installation In many cases, the embedded part is covered with rubber that can greatly improve the working ability of pneumatic butterfly valve to relieve the load. The bending resistance of pneumatic butterfly valve can be expressed by the bending times before destruction. This number is related to the corrugated wall thickness, wave distance, wave height and radius, bending radius, internal pressure and hose diameter. The bending of the hose is caused by the deformation of the wave peak and the valley bottom. At this time, the gap between the inner contour of the two adjacent waves decreases, while the gap between the outer contour increases. The smaller the wall thickness and wave distance of the hose, the larger the wave height and bending radius, the more bending times accepted without damage.