scope:

This standard describes hydraulic and pneumatic linear and quarter-turn actuators for operation of valves and slide gates in utility systems.

Actuator types.

Actuators described in this standard consist of the following types (Figure 1):

1. Linear actuators producing a linear (push-pull) motion.

2. Quarter-turn actuators producing a rotary motion.

a. Cylinder with link and lever mechanism.

b. Cylinder with scotch yoke mechanism.

c. Rack and pinion actuator.

d. Vane actuator.

Actuator function.

Actuators shall produce a rotary torque or linear thrust to actuate a valve or slide gate in open-close, throttling, or modulating service.

Excluded actuators.

Electric-motor actuators are not included in this standard.

Other exclusions.

This standard does not include the following:

1. Piping, controls, and positioners for actuators.

2. The mechanism connecting an actuator to a valve or slide gate.

Purpose

The purpose of this standard is to define the minimum requirements for hydraulic and pneumatic cylinder, pneumatic rack and pinion, and pneumatic vane-type actuators for valves and slide gates, including sizing considerations, design, verification, delivery, handling, and storage.