A FORUM FOR FIRE PROTECTION QUESTIONS & PE EXAM PROBLEMS | SUBSCRIBE NOW
|
There's a varying degree of specifications out there - but I've never really seen it openly discussed or defended.
Some organizations (such as military, many healthcare clients) require schedule 40 for pipe 1 through 2 inches in diameter. Some engineers hardly compile specifications and place no requirements on the pipe thickness. Some projects only allow schedule 40 or even schedule 80. If you're an engineer, what is your basis for recommending different pipe thicknesses for different clients? Is corrosion the only reason why the thicker pipe diameter is specified for your clients? Would be really interested in understanding the reasoning (one way or another) for specifying different pipe thicknesses on suppression systems. Thanks in advance. Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe
5 Comments
We specify minimum schedule 10 for grooved piping, and schedule 40 for threaded. With roll groove fabrication, schedule 10 piping has higher CRR (corrosion resistance ratio) than threaded schedule 40, so it should provide an adequate protection against normal corrosion.
Matthew King
9/10/2019 11:20:42 am
ASME B31 code methods, e.g. B31.3
☼
9/10/2019 11:29:37 am
System design is based on the clients needs and corrosion tends to be a big factor. The Fire sprinkler podcast that has a few segments that hit this topic really well. Go to the April 14, 2019 episode and skip to 27:35. They talk about system components based on client needs regarding expected longevity of the system and pipe thickness. Also go to the Jan 24, 2019 episode and skip to 31:47. They talk about type of pipes regarding corrosion in galvanized vs black. Engineered corrosion solutions and General air both have good resources online to learn more about corrosion.
Pjd
9/12/2019 05:36:24 pm
I want to add here, adding thickness isn't preventing corrosion. It only prevents leaks. You still have increased pipe roughness and obstruction from corrosion. It's like bury your head in the sand if you think it's OK as long as it isn't leaking. Slope your dry systems, routinely empty low point drains, on wet add automatic vents, implement N2 emersion or a MIC plan, and stop placating these lowest bidder wins a holes.
Matthew Virtue
9/13/2019 09:47:30 am
PJD.... The schedule of pipe doesn't prevent leaks. It delays the time corrosion will eat through the pipe. Leave a Reply. |
Free SignupSubscribe and learn something new each day:
CommunityThank You to Our Top
October '20 Contributors!
Your PostThe ToolkitSprinkler Designer or Engineer?
Get all of our tools, including the Sprinkler Database, Friction Loss Calculator, Fire Pump Analyzer and more: 
Filters
All
Archives
December 2020
Daily
Daily discussions are open-ended fire protection, fire alarm, and life safety questions submitted anonymously for the benefit of sharing expertise and learning from other perspectives. Anyone can submit a question here:
Exam Prep
2020 PE Prep Guide
(Available Now!) 
PE Prep Series
(Available Now!) 2020 PE Prep Series
Current Leaderboard (Click to enlarge) 
PE Problems
Visit July-October for daily Fire Protection PE Exam sample questions.
Solutions are posted the day after posting. Comment with your solutions, questions or clarifications. Please note that questions posted are unofficial and in accordance with NCEES rules are intended to be similar to actual exam questions, not actual exam questions themselves. |
RSS Feed
