seamless pipes grades and production methods1. Round bar making Hollow Bar according to customer's demanded material to produce the round bar, then making annealled heat treatment, then drill the hole as customer demanded inner diameter into the round bar, round bar piercing, making rough hole......
| Type | Outer diameter(inner diameter) | Allowed tolerance | Wall thickness allowed tolerance |
Outer diameter | ≥219-457.2mm | -0.8 - +2.4mm | -0.8 - +4.0mm |
| >457.2-660.4mm | -0.8 - +3.2mm | ||
| >660.4-863.6mm | -0.8 - +4.0mm | ||
| >863.6mm | -0.8 - +4.8mm | ||
| Inner diameter | All size | -1.6- 0mm | 0 - +3.2mm |
| Descriptions | Grades |
| Structural pipe | 20# 35# 45# Q345B, 16Mn, Q345B-E, 20Mn2, 25Mn, 30Mn2, 40Mn2, 45Mn2 SAE1018, SAE1020, SAE1518, SAE1045. |
| Liquid pipe | 20# q295b-e, q345b-e |
| High pressure boiler tube | 20G 15MnG 20MnG 15CrMoG, 12Cr1MoVG St35.8, sa106b, sa106c, sa210a, sa210c, A333P2, A333P11, A33P12, A333P22, A33P36, A333P91, A333P92, A335T2, A335T11, A335T12, A335T22, A335T91, A335T23, A335T9 |
| Pipeline | API SPEC 5L, X42, X52, X60, X65,X70,X80 ASTMA53, ASTM A106, ASTM A333, BS301, BS3602, BS3603, BS3604, PSL1, PSL2, DNV-OS-F101, CSA-Z245 |
| Alloy pipe | 4140, 42CrMo, 32CrMo, 15CrMo, |
| Packing | Black paint, Varnish painting, Tarpaulin packing |
| End | Common round end, beveled. |
| Processing | Galvanizing; cutting; making thread outside the pipe; Machining. |
| outer diameter | 16mm- 800mm |
| wall thickness | 4mm- 80mm |









Stable Quality Cheap A350-Lf2 1055 1060 1070 1075 1080 1084 1095 Carbon Steel Round Billet Carbon Steel Round Bar
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