Threadless copper pipe, often referred to as TP pipe, is a seamless copper pipe material manufactured to the requirements of ASTM B 302 - Standard specification for Threadless Copper Pipe, Standard Sizes. This pipe may be manufactured from either of two alloys, C10300 or C12200 with C12200 being the most popular. Both of these alloys are composed of copper (Cu) concentrations in excess of 99.9% thereby making this material an almost pure copper product. Threadless copper pipe (TP) is manufactured in drawn temper (hard) only and is furnished in H58 temper in nominal or standard sizes ¼" through 12". The outside diameter of threadless copper pipe (TP) is essentially the same as schedule 40 pipe, although the wall thickness is much less than that for the same size pipe. The available lengths for threadless copper pipe is 20 foot for sizes ¼" to 10" with 12" being furnished in 15 foot lengths.
Threadless copper pipe (TP) is required, by the standard, to be identified by a gray colored stripe throughout its length that contains the manufacturers name or trademark, the nation of origin and "TP". It is further required to be incised at intervals not less than 1½ feet with the manufacturers name or trademark and "TP" throughout its entire length.
Threadless copper pipe (TP) is usually joined by brazed socket-cup type fittings or socket-cup type flanges. It should be noted that standard copper pressure fittings of the B16.22 or B16.18 type are not compatible for use with TP pipe.
