Why do pneumatic PVDF butterfly valves need to pay attention to cylinder weight? Load distribution of plastic pipelines

Pneumatic butterfly valves on plastic pipelines need to consider both the weight of the valve body and actuator, as well as external support. The connection can be installed, but it does not mean that the pipeline can bear the entire load; The support should be designed according to the actual layout and material conditions.

The center of gravity of the actuator will change the interface bending moment

When the cylinder and accessories are located above or to the side of the pipeline centerline, the weight may form an eccentric load. After thermal elongation or external force, these loads will be redistributed to the valve body connection. Valve pressure qualification does not necessarily mean that it has a bearing proof for any external bending moment. The process layout should identify the center of gravity, pipeline support, and operational displacement, and cannot concentrate the weight of all equipment on two connecting ends.

Fixed points, guidance, and allowable thermal displacement need to be coordinated

Plastic pipes have their own characteristics of thermal expansion and long-term stress, and the support should not only limit unwanted displacement, but also accommodate the expansion and contraction allowed by the design. Adding two rigid fixing points may not necessarily be better than reasonable guidance, and may instead constrain thermal deformation within the short pipe section. The support scheme needs to be evaluated together with the pipeline design, and cannot be determined by a single valve image for all fixing methods. External loads and internal pressures should be managed separately.

The support should not hinder the movement of the butterfly plate and actuator

Tracheal pipes, cables, and brackets need to avoid the range of motion and maintenance channels. Butterfly plate rotation also involves adjacent pipe inner holes, and the support will not automatically solve the problem of insufficient pipe inner diameter. The valve clamp size, mating flange, and pipe wall thickness should be compared separately. The stiffness of the drive interface also needs to be correctly associated with the valve shaft, and the misalignment of the pipeline cannot be corrected by forcibly tightening the bracket, otherwise new additional loads may be generated.

Material compatibility and mechanical support are two independent acceptance criteria

PVDF is suitable for a certain process medium, but it does not mean that the seal, cylinder housing, or control accessories are also suitable for the same corrosive environment. List the temperature and pressure conditions of the valve body medium, the actuator environment, and external loads separately, which can avoid covering all problems with the words' corrosion resistance '. When inquiring, please provide the pipeline material, interface, installation direction, support position, actuator weight, and thermal displacement range; Technical review is based on finished products and pipeline drawings.

Comparison of selection information

Corresponding products and selection entrance

The selection of plastic valves can be accompanied by a list of liquid receiving materials and an external load diagram. The former manages chemical conditions, while the latter manages weight and thermal displacement. Only when both are met can the conditions be maintained for a long-term stable interface and action state.

Related structures can be combinedPneumatic PVDF butterfly valve D671X-10FUnderstanding of specific product information. See more similar directionsPneumatic Valve Product Column。