The problem with "lubricated" plug valves is that they don't get lubricated in the field and after a few months or years they can become impossible to operate.

Reduced bore valves are commonly used for intra-unit applications. Many exceptions exist such as piggable lines, low pressure compressor suction piping.

Multiturn is normally used for valves with a construction where the closing element does not move 90 degrees, eg. normally for globe or gate valves with threaded stems, requiring several turns to clos

There are actually three versions of port size: Full Port is "true full", and can be a relative term based on the I.D. of your Pipe (Schedule of your pipe).

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 .