Fork type pneumatic cut-off flange butterfly valve

QD643W fork type pneumatic cut-off flange butterfly valve

QD643W adopts a flange butterfly valve body and a fork type pneumatic actuator. The current page diameter is DN40-DN600, and the pressure configuration includes PN16, Class150, and JIS10K. The material fields include WCB, 304, and 316L. The product features on the page are single acting, spring reset, and quick cut-off.

What are the characteristics of a fork type pneumatic actuator?

The fork mechanism converts the linear motion of the cylinder into an angular stroke of approximately 90° for the valve stem, and forms an output torque curve suitable for butterfly valve opening and closing. The specifications of the actuator should be selected according to the valve diameter, working pressure difference, sealing structure, gas source pressure, and required safety factor.

How to determine the position of gas loss when resetting a single acting spring?

A single acting actuator can use a spring to drive the valve to a predetermined safe position when it loses air. The actual choice of whether to close or open the valve should be determined based on process safety requirements and consistent with the logic of the solenoid valve action.

How to determine the fast cutting speed?

The action time depends on the size of the actuator, cylinder volume, supply pressure, air path diameter, valve torque, and accessory configuration. This page no longer considers 0.5 seconds, 1 seconds, or 2 seconds as the unified action time for all specifications, nor does it assume SIL2, ATEX, IECEx, or NACE certification.

More pneumatic butterfly valves can be viewedSelection of pneumatic valvesThe overall structure of the butterfly valve is shown inButterfly valve manufacturer and selection。

Frequently Asked Questions

Does QD643W close by default due to gas loss?

It is not enough to judge based solely on a single acting structure, and the direction of spring reset and the safe position for gas loss should be determined according to project requirements.

Can all calibers be closed within 1 seconds?

No, the action time is related to the actuator, caliber, gas source, and load.

What safety and explosion-proof materials are required for QD643W to be used in emergency circuit disconnection?

The applicable functional safety requirements, on-site hazardous areas, and complete valve configuration information should be checked separately. The certificate of the actuator or individual accessory cannot automatically prove that the entire circuit has reached the specified level. Specific requirements need to be specified when ordering.