×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Relief Valve required on Fuel Train?

Relief Valve required on Fuel Train?

Relief Valve required on Fuel Train?

(OP)
I have conflicting information on the requirment for a Pressure Safety Relief valve on the natural gas supply line after the regulator and before the automatic fuel shut off valves.  Does anyone know which code lists that requirment?
The piping between the reducing valve and the burner is specified at the same pressure requirment as the upstream line so it would not be to protect the line.

This is a forced draft, 200,000 lb/hr, gas fired package boiler.

RE: Relief Valve required on Fuel Train?

bh1,
The piping is not the problem, as you point out it has same design as the upstream piping.  The automatic fuel valves probably have a low pressure rating of maybe 15 psi, so that a relief valve is required in event of the pressure regulator failing open / not shutting off tight.  
Remember to route the vent from pressure relief valve, and the vent from pressure regulator to a safe location, above burner and away from fan inlet.    

RE: Relief Valve required on Fuel Train?

(OP)
What if my shut off valves are also rated above the supply line pressure.

Is there some code about relief valves being needed to limit the potential gas flow to a burner if the high gas pressure switch failed at the same time as the gas regulator?

RE: Relief Valve required on Fuel Train?

bh1,

Gas fired boilers are not my area of expertise but I do recall a discussion some time back about fuel gas supplies that you may find interesting.  

See if these help...
thread794-104500
and the referenced link...
http://www.driedger.ca/ce5_fh/CE5_FH.html

RE: Relief Valve required on Fuel Train?

You will want to take a look at NFPA 85 (Boiler Combustion Systems Hazards Code) which lists the current standards (also check with the local jurisdiction).

Specifically in the NFPA take a look in Annex A and the figures that show typical fuel supply systems - then let your fingres do the walking to figure out what your system requires.

Cheers.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources