... .2 have S2, S4, S5 of pipe pressure level 5 series. Nominal diameter from 20 to 160 mm, etc DuoZhong 50 ... tube for more than 40 °C the fluid temperature, S2 to S3.2 series for normal use hot water pipe, tube, the ... fluid temperature more than 70 °C, for the service life ... ; Other industrial, agricultural tube. PPR hot and cold water pipe series