Seamless tube lines
Seamless steel pipe rolling lines：
Seamless steel pipe is divided into two types, hot-rolling & cold-rolling (cold-drawing) seamless steel pipe, including low-alloy steel pipe, stainless steel pipe, medium-pressure boiler steel pipe, high-pressure boiler steel pipe, geological steel pipe and other steel pipes.
The outer diameter of hot-rolled seamless tube is generally greater than 32mm, wall thickness from 2.5mm to 75mm; for cold-rolled seamless pipe, the outer diameter can be as small as 6mm, and thickness to 0.25mm. For thin-walled tubes, the outer diameter can be as small as 5mm, with thickness less than 0.25mm. Cold-rolled pipe has higher precision than hot-rolled pipe.
The raw material for seamless steel pipe is round bar. Round bar is cut to fixed length by cutting machine, and then transferred to reheating furnace for heating at about 1200℃. After heated, it is transferred into cone roll piercer for piercing. This piercer has high production efficiency, good product quality, greater expanding/piercing, and it can pierce variable steel grade. After piercing, the round billet is skew-rolled, continuous rolled, and extruded by rolling mill, and then for extracting and sizing, after sizing. Then, it runs into cooling tower to be cooled, and to straightening machine to be straightened. At last, the pipe is delivered by conveyor to metal flow detector (or hydraulic testing) for internal inspection.
Hot-rolled seamless steel pipe process:
Round bars → Reheating furnace → Piercer → Rolling mill → Extractor → Sizing (reducing) → Cooling → Hollow billet→ Straightening machine → Hydraulic testing (flaw detector) → Marking (labeling) → Warehouse
Cold-rolled seamless steel pipe process:
Round bars → Reheating furnace → Piercer → Heading machine → Quenching → Pickling → Oil coating (coppering)→ Multi-passes cold rolling (or drawing) → Hollow billet → Thermal treatment → Straightening machine→ Hydraulic testing (or flaw detector) → Marking (labeling) → Warehouse
|
Type |
Main materials |
Standards |
Spec. |
Application |
|
Alloy pipe |
Cr5Mo(P5/T5, STFA25); 15CrMo(P11, P12, STFA22) 13CrMo44, 12Cr1MoV; P22(10CrMo910); T91/P91, P9/T9; |
GB5310-2008; ASTM A335/A213; ASME SA335; DIN17175; JISG3467; JISG3458; CNB-9 |
∮14-508×2-50mm |
For high temperature and high pressure resistant, low temperature resistant, or corrosion resistant pipelines in oil, chemical, electrical, and boiler industries |
|
Pipe for High pressure boiler |
20G, 12Cr1MoVG, B, 15CrMoG, ST45.8/Ⅲ |
GB5310-2008 ASTM A106 DIN17175 |
∮14-824×2-80mm |
For high temperature and high pressure resistant fluid transfer container or pipelines of boilers in power plant and nuclear power plant |
|
Petroleum cracking pipe |
10, 20, 16Mn, 15CrMo |
GB9948-2006 |
∮19-530×2-30mm |
For pipelines of boilers in oil refinery, of heat exchanger, and of fluid transportation |
|
Pipe for fertilizer equipment |
10, 20, 16Mn, 12Cr2Mo |
GB6479-2000 |
∮18-325×2-35mm |
For high temperature and high pressure fluid pipeline of fertilizer equipment |
|
Pipe for low and medium pressure boilers |
20 |
GB3087-2008 |
∮25-426×2.5-30mm |
For pipelines of low and medium pressure fluid transportation for industrial boiler and domestic boiler |
|
Fluid pipe |
10, 20, Q345B, STPG370 |
GB/T8163-2008 |
∮10-660×1.5-40mm |
For fluid transportation pipelines in projects and for heavy-duty equipment |
|
Structural pipe |
10, 20, 35, 45, 40Cr, Q345B |
GB/T8162-2008 |
∮10-530×1.5-60mm |
For common structure and mechanical structure |
|
Line pipe |
B, X42, X52PSLII |
ASTM A106/A53; API 5L |
∮10-610×1.5-35mm |
For gas, water and oil transportation in oil and natural gas industry |
|
Pipe for hydraulic service |
27SiMn |
GB/T17396-1998 |
∮95-245×9-30mm |
For manufacture of hydraulic support, cylinder and column for mining |
|
Pipe for watercraft |
410I, 410II; 410III, 410G |
GB/T5312-2009 |
∮18-530×3-20mm |
For pressure pipes (pressure grade I & II) used in watercraft boilers and overheater, etc |
|
Oil pipe |
J55, K55, N80I, N80Q, C90, C95, T95, P110, Q125 |
API 5CT; SY/T6194-1996 |
∮60-114×4-12mm |
For oil transportation from oil deposit to the ground by means of oil pumping unit |
|
Driller pipe |
E75, X95, G105, S135 |
API 5D; SY/T5987-1994 |
∮60-139×6-13mm |
For oil and gas well drilling |
|
Pipe sleeve |
J55, K55, N80I, N80Q, C90, C95, T95, P110, Q125 |
API 5CT; SY/T6194-1996 |
∮114-340×4-13mm |
For oil and gas well wall support |