Recent content by Chance17

In real life the rupture disk should be fully open when the relief valve activates. If the disk partially opens and the differential is not great enough the safety valve may chatter. My recommendation is to set the rupture disk at 15-psig and decrease the safety valve setting to say 13-psig...

[b]Message to Latexman, LittleInch, and Don1980 As Gomer Pyle says "Thank You - Thank You - Thank You" Chance17

I am evaluating a Revamp project.It requires a 4"x P x 6" safety valve. The inlet line loss is between 12% to 16% of set at actual valve capacity. The Client says the next opportunity to increase inlet pipe size will be in the year 2030. The outlet pipe friction slightly exceeds 50$ of set. The...

I am evaluating a safety valve with low differential pressure Storage drum 10-ft dia by 30-ft S-S. Contingency = Hexane Liquid overfilling Safety Valve Activation pressure = 75-psig which equals vessel MAWP Downstream disposal = 10-psig normal -- nearly closed containment Containment is...

I am looking at a turbine installed in the field. The inlet flange is 250# ASA The outlet flange is 125# ASA It appears the inlet pressure rating is different than outlet. I'm not clear how I should evaluate the turbine mechanical pressure limit

Most Turbine documents have inlet Design Pressure and Outlet design pressure. I don't understand the need for an Outlet Design rating. Is this an actual mechanical casing rating? Is this a pressure at which turbine fails to deliver power? Is this a pressure for bearing loads. Given 120-psig...

I believe this standard comes from API 520 In flammable vapor service, the minimum exit velocity should be 100 ft/s (30 m/s) at 25% of the rated capacity of the PR valve (i.e., calculated flow using 25% of the installed PR valve’s effective orifice area). For modulating type POPRVs the minimum...

Most everyone is familiar with safety valve chatter due to excessive friction losses in inlet pipe. But given a liquid filled system with long piping and the pressure source liquid near (but below) safety valve set, Is it possible to have repeated activation due to hydraulic surge (not friction...

How should someone model the friction loss in a half open gate valve using Crane 410 methods? This is embedded in a PE examination question.

Can someone advise if there is an ASHRAE standard for sizing compressor discharge safety valve. I am evaluating a R-134a compressor purchased in 1999. The safety valve rated flow is sized for about 25% of compressor rated capacity. I'm wondering if this is an ASHRAE standard. My current client...

Safety Valve activation = CDTP + Constant back pressure. If constant back pressue is atmospheric, activatio = CDTP

I'm looking at a set of PID's for a turbine driven pump. The Client has no record files for either pump or turbine. Using 150-psig steam and exhaust to atmosphere, is it reasonable to estimate 150-psig maximum possible pump discharge pressure?

I have a client that operates a rail car facility with 17 folding gangways. Normally the gangways are operated using 80-psig nitrogen from header. For nitrogen outages, the client wishes to use a small portable air compressor. The vision is for the compressor and driver (gasoline) to be mounted...

I view gas blow by as both gas and liquid exiting the bottom of vessel. If the liquid is moving or turbulent, I don't see how it can freeze

Can anyone advise a typical Xt factor for Gate valves?