copper pipe pressure ratings

[Kyle Kraft]

Check out this table at Copper.org. Table 3a is for type K, 3b for type L, and 3c for type M. http://www.copper.org/applications/plumbing/techref/cth/tables/cth_table3c.htm

Enjoy!!

[Kent Fitzgerald]

Also look here:
http://www.copper.org/applications/plumbing/techref/cth/tables/cth_table4.htm

Depending on the solder used, the pressure rating of joints can be considerably lower than that of the pipe itself.

[Kyle Kraft]

Kent,

Good information. I personally don't use solder containing lead anymore. Not because I'm afraid of lead, but because I like the way lead free solder goes on....for me, it's easier to work and get a leak-tight joint every time.

My next question is does lead free solder fit into the second category on the chart? Is it the tin/antimony stuff or one of the other categories further down? The pressure rating of the joint increases greatly when you use a solder other than the lead based stuff...it appears.

[Kent Fitzgerald]

Well, now you got me curious, so I looked up some manf's info:

http://www.oatey.com/apps/catalog/showprod.asp?ctg=78&subctg=0&Submit1=Go+to+Product+Catalog

I've been using (for general plumbing) Oatey Safe Flo, which is a Tin / Copper / Silver / Bismuth alloy, with a lower melting point (and I assume less strength) than the 95/5 Tin / Antimony alloy.

[Bart Leetch]

Thanks Kyle this supports what my plumber was telling me yesterday about type M being plenty strong enough for home shop use. the weakest point in any system is going to be the joints. Depending on the solder used.

[Ken Garlock]

Bart, don't worry about a properly soldered joint. The solder is in shear stress and provides a lot of surface area for resistance.

That said, when installing my 1/2" copper air distribution system, I used solder with 2% silver content for the extra measure of strength. There is a good selection of solder at McMaster & Carr.