GB / T 29047-2021, lub npe "Prefabricated Directly Buried Insulated Pipes and Fittings-Rigid Polyurethane Foam Insulation with High-density Polyethylene Outer Casing," yog lub teb chaws tseem ceeb tshaj plaws rau cov txheej txheem prefabricated ncaj qha faus insulated kav. Tshaj tawm thaum Lub Yim Hli 2021 thiab siv tau txij li lub Peb Hlis 2022, nws hloov cov ntawv dhau los, GB / T 29047-2012.
Tus txheej txheem tshiab txhais nws cov peev txheej, npog prefabricated ncaj qha faus cov kav dej thiab fittings tsim rau kev ua haujlwm tas li ntawm qhov kub txog li 120 degree, nrog rau qee zaus qhov kub siab tshaj txog 130 degree. Hais txog cov qauv ntawm cov khoom, tus qauv qhia qhov muaj pes tsawg leeg-muaj xws li high-density polyethylene (HDPE) txheej txheej, ib txheej txheej polyurethane ua npuas ncauj rwb thaiv tsev, thiab cov yeeb nkab steel los yog haum-nrog rau cov kev xav tau, kev sim, kev soj ntsuam xyuas, cim, kev thauj mus los, thiab kev cia khoom.
Rau cov txheej txheem rwb thaiv tsev, tus txheej txheem tswj hwm tias qhov ntom ntawm polyurethane ua npuas ncauj yuav tsum yog tsawg kawg 60 kg / m³ ntawm txhua qhov chaw, qhov nruab nrab ntawm tes yuav tsum tsis pub tshaj 0.5 hli, thiab cov ntsiab lus kaw ntawm tes yuav tsum yog tsawg kawg 88%. Rau cov ua npuas ncauj uas tsis muaj dej, qhov thermal conductivity ntawm 50℃yuav tsum tsis pub tshaj 0.033 W / (m·K), thiab lub zog compressive yuav tsum yog tsawg kawg yog 0.3 MPa.
Hais txog cov txheej txheem sab nrauv, tus qauv yuav tsum tau siv cov yeeb nkab-qib high-density polyethylene resin (PE80 lossis siab dua); Kev siv cov khoom siv rov ua dua lossis rov ua dua tshiab yog txwv tsis pub siv. Lub casing sab nrauv yuav tsum muaj qhov ceev ntawm 940 thiab 960 kg / m³, elongation ntawm kev tawg yam tsawg kawg yog 450%, lub zog tawm los ntawm tsawg kawg yog 19 MPa, thiab cov ntsiab lus carbon dub ntawm 2.5% ± 0.5%.
Rau cov neeg yuav khoom, kev nkag siab txog cov kev qhia tshwj xeeb no pab txhawb cov hom phiaj thiab kev lees txais cov khoom lag luam zoo. Nws raug nquahu kom qhia meej meej hauv cov ntawv cog lus tias cov khoom yuav tsum ua raws li GB / T 29047-2021 thiab xav kom cov chaw tsim khoom muab cov ntaub ntawv xeem thib peb.