What the manufacturers do is select the shortest possible length from the available sizes in which they can fit the ball, seats, flanges, assembly of the flange and any body bolting.

These are crayons, tablets, or paints that indicate a temperature by melting at specific the specific temperature indicated on the crayon. Templestick is one brand name and had been around a long time

In normal conditions (not limitated as in critical/cavitating/flashing cases) there is a relation between flow and pressure drop and providing you get a curve CV/Aperture it shouldn't be difficult to

A trunnion mounted valve means that the ball is constrained by bearings and is only allowed to rotate. The bearings act on the trunions .

Often there is confusion regarding DPE (double piston effect) seats, and DBB (double block and bleed), and we now have DIB-1 and DIB-2 in Annex B of ISO 14313/API 6D in the mix.

Ball valves torque is determined by the seat material, the ball material, the process fluid lubricating (or fouling) the seats, the pressure differential loading the ball against the seat, the design

most low pressure applications request 2 piece floating ball valves and when not specified I've always sold the 2 piece floater. What instances would a 150# or 300# trunnion be the preferred design.

a description for the seating of a 30inch ball valve as Primary metal and secondary soft. Does it mean that the ball is soft seated.