PE-X: Cross-linked polyethylene 1
PAP: Aluminum-plastic composite pipe 2
PP-B: Impact-resistant copolymer polypropylene (Korea used to call it PP-C)
PP-R: random copolymer polypropylene
PB: Polybutene is high temperature resistant
PE-RT: Polyethylene
Note 1: Cross-linked polyethylene is divided into peroxide cross-linking (PE-Xa), silane cross-linking (PE-Xb), electron beam cross-linking (PE-XC) and azo cross-linking (PE-Xd) according to the production method. ) four. Among them, peroxide cross-linking and silane cross-linking are two kinds of cross-linked polyethylene pipe products commonly used in China.
However, peroxide cross-linking is not widely used due to excessive oxygen penetration. Silane cross-linking is banned in Europe in 2004 because the cross-linking agent silane is toxic. Electron beam cross-linking (PE-XC) is a healthy and environmentally friendly pipe that uses physical methods to change the molecular structure. , azo-crosslinking (PE-Xd) is in the experimental state.
Note 2: There are three types of aluminum-plastic composite pipes on the market, PE/AL/PE; PE/AL/XPE; XPE/AL/XPE. The first is that the inner and outer layers are polyethylene, the second is that the inner layer is cross-linked polyethylene, the outer layer is polyethylene, the third is that the inner and outer layers are both cross-linked polyethylene, and the middle layer is aluminum. The first type is generally used for cold water pipeline systems, and the latter two are generally used for hot water pipes, which can be used as floor heating pipes.