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Next step is to draw orphan joints/nodes to the location where the centerline of the trunnion will be welded to the elbow. In this example we click the Draw joint icon where we enter -18" in the Z direction and click the two elbow joints as shown below left to add joints where the trunnion will be welded to the elbow. Next, assign a Body constraint to each pair of joints in order to create a zero weight rigid connection. You will need to assign a different Body constraint to each pair of joints. As shown below right, there needs to be a separate Body constraint for each of these pairs of joints. You don't want to select all 4 joints and assign the same Body constraint.
Next, draw additional 2 orphan joints/nodes below to the base of the trunnion. The offset distance of that newly drawn joint will define the length/height of the trunnion. In this example we'll make the trunnion 16" long. Click Draw Pipe icon, change the pipe property set to the 8"STD section which we imported earlier, clicking the base joint then double click the joint above it in order to draw the trunnions. Draw anchors at the base of the trunnions to complete.
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