The picture shows a 3 Way ball valve with the bolt heads encapsulated in the square flange. The use of cap screws and the corresponding tapping in the opposite square flange instead of nuts is a unique way to increase the space for nuts. This arrangement allows more space for flange nuts used at the customer end. This is especially useful where face- to- face distance constraints does not allow the increase in space for nuts.
Picture showing Cap Screw Head
Picture showing tap instead of nut
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