Carbon steel or stainless steel + flexible graphite combined gasket is usedforClassl50 gate valve

I'm new here and have registered through desperation. I know very little about plumbing. I'm a girly living alone and think my plumbers are telling me rubbish. Any advice would be much appreciated as

The new method / design we are using eliminates Exhaust Gas reversion while increasing volumetric efficiency and effective compression ratio. This time it is working really well, so far (1000 miles).

I have been reading posts on this site for a good time now and I'm astounded by what I've been able to learn here. It's now my turn to ask a question and I'd really appreciate any help that anyone ha

I am involved with the design of a pumphouse which consists of four (4) fixed speed centrifugal pumps (duty/assist/assist/assist), each pump being large, 4500m3/hr at 50m total head.

I have a question concerning pressure changes. We are trying to make small pressure changes to a static pressure of 5psi by varying the volume in a cylinder.

Question about settings for our thermal relief PRVs around valves in tank farms. Nornmally we have the PRvs set at 25 psi in the piping and 75 psi at the valve directly off the tank (our tanks are not

My company builds industrial sized centrifugal fans (40"-120"+ impeller diameters), and we treat "Fan Engineering" like it is the Bible.