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If you want to consider the weight and mass of a valve operator/actuator, including the eccentricity of its CG, define a user defined valve by going to Define>Components>Valves and click 'Add new' button. Go to the option "Has operator/actuator" and change default No to Yes. That opens up additional options to enter actuator weight and offset distance and direction from centerline of the actuator CG. This dialogue enables users to change units on the fly.

Some valve bodies such as gate valves have a CG that is significantly offset from the pipe centerline. Under seismic load, ignoring this eccentricity and the resulting torsional moments from lateral loads may be unconservative, particularly with large diameter valves. The Eccentric Weight option enables users to specify the percentage of valve body weight which is eccentric and to specify offset from centerline distance and direction of the valve CG using local axes.

Modeling a support for Valve actuator 

Modeling a valve actuator with a support requires a different modeling approach. Instead of specifying "Yes" to Operator/Actuator and then entering weight and offsets, leave the Operator/Actuator field "No". Instead we will use Draw joint to draw a joint/point offset from the valve to the CG of the actuator/operator, connect the joint to the valve using a body constraint, assign a -Z downward load on that joint for the actuator weight, then draw, insert, or assign a pipe support to the newly drawn joint.

If static acceleration or dynamic load cases are defined, the user will need to go to Define>Mass Sources to specify the load pattern used for the actuator weight to be included in the mass source.

       

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