GB 9948 07Cr18Ni11Nb Seamless steel tubes for petroleum cracking, ASTM A213, EN 10216-5, UNS S34779, X7CrNiNb18-10, TP347H, SUS347H TB, 10, 20, 12CrMo, 15CrMo, 12Cr1Mo, 12Cr1MoV, 12Cr2Mo, 12Cr5Mo, 12Cr9Mo, 07Cr19Ni10, 07Cr18Ni11Nb, 07Cr19Ni11Ti, 022Cr17Ni12Mo2

GB 9948 Seamless steel tubes for petroleum cracking

Standard: GB 9948
Equivalent Standards: ASTM A213, EN 10216-5, ISO 9329-2

Material: 07Cr18Ni11Nb
Equivalent Materials: S34779, X7CrNiNb18-10, TP347H, SUS347H TB

Chemistry Composition

C, %	Si, %	Mn, %	P, %	S, %	Cr, %	Ni, %	Nb, %
0.04-0.10	1.00 max	2.00 max	0.030 max	0.015 max	17.0-19.0	9.00-12.0	8*C-1.10

Mechanical Properties

Tensile Strength , MPa	Yield Strength, MPa	Elongation, %	Hardness (HBW)
520 min	205 min	35 min	187 max

Outside Diameter & Tolerance

Hot Rolled	Outside Diameter, mm	Tolerance
	Outside Diameter, mm	Ordinary	Advanced
	OD≤54	±0.50mm	±0.30mm
	54＜OD≤325	±1%	±0.75%
	OD>325	±1%	-
Cold Drawn	Outside Diameter, mm	Tolerance
	Outside Diameter, mm	Ordinary	Advanced
	OD≤25.4	±0.15mm	-
	25.4＜OD≤40	±0.20mm	-
	40＜OD≤50	±0.25mm	-
	50＜OD≤60	±0.30mm	-
	OD>60	±0.75%	±0.50%

Wall thickness & Tolerance

Hot Rolled	Wall Thickness, mm	Tolerance
	Wall Thickness, mm	Ordinary	Advanced
	WT≤20	+15%/-10%	±10%
	WT>20	+12.5%/-10%	±10%
Cold Drawn	Wall Thickness, mm	Tolerance
	Wall Thickness, mm	Ordinary	Advanced
	WT≤3.0	±0.30mm	±0.20mm
	WT>3	±10%	±7.5%

GB 9948 specifies the classification, code, size, shape, weight, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of seamless steel tubes for petroleum cracking. GB 9948 is applicable to seamless steel tubes for furnace tubes, heat exchanger tubes and pressure piping for petrochemical industry.
GB 9948规定了石油裂化用无缝钢管的分类、代号、尺寸、外形、重量、技术要求、试验方法、检验规则、包装、标志和质量证明书。GB 9948适用于石油化工用炉管、热交换器管和压力管道用无缝钢管。

Manufacture: tubes to GB 9948 shall be manufactured by hot rolled or cold drawn.
Heat Treatment: the tubes shall be produced by solution treatment.
Inspection & Test: chemistry composition analysis, tension test, flattening test or bending test, flaring test, hardness test (alloy & stainless), impact test, macroscopic examination, non-metallic inclusions, microstructure, intergranular corrosion test (stainless), NDT, surface inspection and dimension check.

Length: 4000mm; 6000mm; 9000mm; 12000mm; and so on.
Max developed length: 30 meters, also U bending, finning, studded process can be provided.
Option: surface polishing as preparation work done for further processing.

Keyword: GB T 9948, High Pressure Steel Pipe, Heat Exchanger Steel Tubes, Furnace Tubes, Piping

Home | About Us | Product | Know How | Contact Us