The Trunnion ball valves have ample backing to the ball. The assistance is in form comparable to a shaft, and it’s known as a trunnion. The Trunnion soaks up any added force coming in the circulation, therefore reducing the stress to the valve seat as well as the ball. Argus http://trentonqahmr.blog5.net/36930373/5-easy-facts-about-trunnion-ball-valve-described