In the previous period, PP-c pipes and fittings appeared in the domestic market, and their installation methods were consistent with pp-r. Many people don't know the difference between PP-R and PP-c, resulting in many misunderstandings and confusion. In the international standard, polypropylene cold and hot water pipes are divided into pp-h, PP-B and PP-R, without pp-c. The difference between the three PP pipes is that the stiffness of pp-h, PP-B and PP-R pipes decreases in turn, and the impact strength increases in turn.
Among the three kinds of PP pipes, the impact resistance of pipes is PP-R > PP-B > pp-h, the thermal deformation temperature of pipes is pp-h > PP-B > PP-R, the rigidity of pipes is pp-h > PP-B > PP-R, the bursting temperature of pipes at room temperature is pp-h > PP-B and PP-R, and the chemical corrosion resistance of pipes is pp-h >PP{0}B thiab pp-r. Piv nrog rau lwm cov yeeb nkab PP, qhov zoo tshaj ntawm PP -R yeeb nkab yog tias nws tsis tsuas yog txhim kho qhov qis - kub brittleness ntawm pp-h, tab sis kuj muaj qhov ntev zoo {{5} }}lub sij hawm dej siab ua haujlwm ntawm qhov kub siab dua (60 degree), tshwj xeeb tshaj yog thaum siv rau cov kav dej kub, qhov ntev - lub sij hawm lub zog zoo dua pp-h thiab pp{{ 9}b. 1 PP-c yeeb nkab nyob rau hauv kev ua lag luam yog tiag tiag PP-B yeeb nkab, thiab nws cov khoom raw yog cov khoom tshwj xeeb rau thaiv copolymerized polypropylene yeeb nkab. PP-B yeeb nkab yog ib hom yeeb nkab dej txias thiab dej kub, uas yog pheej yig heev, thiab nws cov cua sov ua haujlwm thiab siab tsis kam yog qhov sib txawv ntawm pp-r. Piv txwv li, cov kev pabcuam raug cais raws li 2, lub siab tsim yog 0.6MPa, phab ntsa tuab ntawm dn25mm yeeb nkab, PP-R yeeb nkab yog 3.5 hli, thiab phab ntsa tuab ntawm PP-B ( PP-c) yeeb nkab yog 5.1mm; Lub siab tsim yog 0.8MPa, dn25mm, phab ntsa tuab ntawm PP-R yeeb nkab yog 4.2mm, thiab PP-B (PP-c) siv tsis tau. Vim tias qhov xav tau ntawm phab ntsa thickness yog tuab heev. PP-c yeeb nkab nrog tib lub qauv thiab loj li PP-R hauv khw muaj ntau qhov kev pabcuam qis dua thiab tsis tuaj yeem sib xyaw nrog PP-R yeeb nkab, cia nyob ib leeg hloov PP{ {37}}R yeeb nkab nrog PP-c yeeb nkab tom qab txiav txim siab cov kev pabcuam. Kev pabcuam 2 qhia tias qhov ntsuas kub tsim yog 70 degree rau cov dej cua sov.
