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 in the Define>Components>Valve dialogue and then entering weight and offsets, instead leave the Operator/Actuator field "No". We will use Draw joint to draw a joint/point offset from the valve to the CG location of the actuator/operator, connect the joint to the valve using a body constraint (zero weight rigid connection), assign a -Z downward point load on that joint for the actuator weight, then draw, insert, or assign a pipe support to the newly drawn joint. If you're connecting to the valve midpoint, you will need to draw a joint at the valve midpoint.

If static acceleration or dynamic load cases are defined, the user will also need to go to Define>Mass Sources to specify the load pattern used for the actuator weight to be included in the mass source. Do not add DEAD load pattern if the "Element self mass" option is checkboxed, otherwise you will double count selfweight mass. In this example we defined a new load pattern called ACTUATOR WT which was added to the mass source as shown below.

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