Cov txheej txheem txheej txheem rau cov kav dej tua hluav taws

Ib feem ntawm GB 5135 no qhia txog cov kev xav tau, cov qauv kev sim, kev tshuaj xyuas cov cai, ntim khoom, kev thauj mus los thiab khaws cia cov kav hlau coated rau cov tshuab tsis siv neeg txau. Qhov no siv rau cov yeeb nkab steel coated nrog epoxy resin uas nws cov khoom txheej sab hauv tsis ntau tshaj 300mm nyob rau hauv nominal txoj kab uas hla siv nyob rau hauv tsis siv neeg sprinkler system.