JIS G3445 Stkm19A Carbon Seamless Steel Pipe Tube for Machine Structure

• After-sales Service: Technical/Sample/Quality
• Type: Seamless
• Technique: Hot-Rolled+Cold-Drawn
• Material: Alloy Steel
• Surface Treatment: as Required
• Usage: Hydraulic/Automobile Pipe, Machinery Industry, Special Purpose
• Model NO.: STKM19A
• Section Shape: Round
• Cutting Service: Available
• Mtc: 3.1 or 3.2 Certificate
• Transport Package: Seaworthy Standard Package
• Specification: 30-850mm
• Trademark: SHUNFU
• Origin: China
• Production Capacity: 50000tons/Year

Product Description

JIS G3445 Carbon Steel Tube For Machine Structure

JIS G3445 Specification for seamless and welded steel tubes for automobile, mechanical and general engineering purposes - Specific requirements for cold drawn seamless steel tubes. cold drawn seamless tubing possesses a high strength-to-weight ratio and can be processed to provide a combination of desired characteristics: dimensional accuracy; good surface quality; excellent micro-structure uniformity; good machinability; and high tensile properties. It is also suited for such post-treatments as carburizing and heat treating.
 

Benefits Of G3445 Seamless Steel Tubes

Higher Strength & Hardness Properties
Size Accuracy
Enhanced Appearance
Uniform Micro-structure
Easier To Machine
Superior Finish In Subsequent Manipulations
 

G3445 Seamless Steel Tubes Applications

1.Hydraulic Cylinders
2.Auto and Truck Axles
3.Suspension parts and shock absorbers
4.High Speed Shafts and rollers
5.Bearings and Spacers
6.Roll cages
7.Agricultural components and many other machined tubular parts.
 

Standards

JIS G3445 carbon steel tubes for machine structure

 

G3445 Steel Tubes Chemical Component

Grade		Symbol of prade	C	Si	Mn	P	S	Nb or V
Grade 11	A	STKM11A	0.12 max.	0.35 max.	0.60 max.	0.040 max.	0.040 max.	-
Grade 12	A	STKM12A	0.20 max.	0.35 max.	0.60 max.	0.040 max.	0.040 max.	-
	B	STKM12B
	C	STKM12C
Grade 13	A	STKM13A	0.25 max.	0.35 max.	0.30 to 0.90	0.040 max.	0.040 max.
	B	STKM13B
	C	STKM13C
Grade 14	A	STKM14A	0.30 max.	0.35 max.	0.30 to 1.00	0.040 max.	0.040 max.	-
	B	STKM14B
	C	STKM14C
Grade 15	A	STKM15A	0.25 to 0.35	0.35 max.	0.30 to 1.00	0.040 max.	0.040 max.	-
	C	STKM15C
Grade 16	A	STKM16A	0.35 to 0.45	0.40 max.	0.40 to 1.00	0.040 max.	0.040 max.
	C	STKM16C
Grade 17	A	STKM17A	0.45 to 0.55	0.40 max.	0.40 to 1.00	0.040 max.	0.040 max.	-
	C	STKM17C
Grade 18	A	STKM18A	0.18 max.	0.55 max.	1.50 max.	0.040 inax.	0.040 max.	-
	B	STKM18B
	C	STKM18C
Grade 19	A	STKM19A	0.25 max.	0.55 max.	1.50 max.	0.040 max.	0.040 max.	-
	C	STKM19C
Grade 20	A	STKM20A	0.25 max.	0.55 max.	1.60 max.	0.040 max.	0.040 max.	0.15 max.

 

G3445 Steel Tubes Delivery Condition

Hot finished seamless steel tube
Cold finished seamless steel tube
As electric resistance welded steel tube
Hot finished electric resistance welded steel tube
Cold finished electric resistance welded steel tube
Butt welded steel tube
Automatic arc welded steel tube
 

G3445 Steel Tubes Drawing Process

Floating/Drawing process of pulling a metal bar, rod, or wire through the whole of a die to alter its finish, shape, size, and/or mechanical properties. The tube drawing technique reduces the outer diameter, inner diameter, and wall thickness of the tube. The integrity of the surface of the tube is maintained, ideal for stainless steel tubes. 
 

G3445 Steel Tubes Annealing Process

Annealing is used to soften the metal before further cold working or fabrication processes, and improves the overall metallurgical microstructure of the tube. During tube reduction or cold drawing, it can become hard and somewhat brittle. To be able to draw the tube again, stresses formed during cold working need to be removed to return the material to its normal state.
During annealing the tube is heated to a controlled temperature (up to 2100°F) and soak time. Through this process the tube remains in shape, but the grains in the structure of the tube reform into a regular unstressed pattern. The resulting annealed tube is softer and suitable for redrawing.
 

G3445 Steel Tubes Manufacturing process

Tubular Products seamless mechanical tubing is produced from solid round billets by rotary piercing and then rolled in an Assel mill that permits an extremely broad range of diameter/wall thickness ratios. Tubes are then processed through a multiple-pass size reducing mill and a rotary sizer.
Tube lengths from the hot mill are slowly air cooled or moved directly to a unique is othermal annealing furnace to ensure a uniform microstructure hardness to promote excellent machinability. This process contrasts with conventional slow-cool furnaces, where tubes are cooled in bundles. That can result in variations in microstructure and hardness from tube to tube and even within a tube itself.
After cooling, tubes are pickled in an acid bath to remove mill scale and inspected. Minor imperfections are removed by grinding prior to cold drawing and additional processing. During the cold drawing process, tubes are drawn in a controlled fashion over a mandrel and through a die to reduce the diameter and wall thickness. After forming and depending on customer requirements, the tubing is stress relief annealed, straightened and cut to length. Tubes are inspected for dimensional accuracy and surface finish.
Cold working, applied to both inside and outside surfaces, improves surface finish, increases tensile properties, improves machinability in many grades and results in more precise dimensions. Outside diameter and wall thickness tolerance are improved by approximately 50 percent.
 

G3445 Steel Tubes Packaging

Straight lengths of seamless tubing can be individually sleeved in paper or plastic and/or packaged in our unique cardboard spacers to ensure no damage occurs during transit. Coiled seamless tubes are horizontally packed using paper or cardboard separators to prevent tube-to-tube contact. All tubing is packed in either wooden crates lined with wax craft paper, tri-wall clay-coated reinforced cases, or standard cardboard boxes. Plastic end caps that prevent foreign material from getting inside the tubes are also available upon request.
 

Other Services

1 Cutting: Small pieces
2 End: Plaint or Beveled or threaded
3 CNC Machine: Produce as your drawing
4 Package: Bare/Nylon/Canvas/Wooden
5 Payment:T/T, L/C, O/A(request credit)
6 Transport:FOB/CFR/CIF/DDU/DDP (train/ship/Air)