Stop valve for pipeline - has cams generating rotary and axial plug movement from actuator rotation

摘要

The stop valve has a plug turned through less than 90 deg. when the actuator is turned for this amount. Actuator rotation is converted into a rotary and linear movement of the plug, using cams to position the plug in relation to the seat and press it against the latter. One cam controls the first 70 deg. of plug movement, without the plug engaging the seat. The second cam controls the final closing movement/ USE/ADVANTAGE : At high temps. and pressures, reducing plug wear and force needed for operation.