Premium Quality Black Annealed Steel Pipe for Fabrication Needs

• Customization: Available
• After-sales Service: Free
• Warranty: Free
• Model NO.: JIS EN ASTM DIN GB/T
• Type: Seamless or Welded
• Technique: Cold Drawn or Cold Rolled
• Material: Carbon and Alloy
• Surface Treatment: Oiled
• Usage: Hydraulic/Automobile Pipe, Machinery Industry, Construction & Decoration, Special Purpose
• Section Shape: Round
• IATF16949: Yes
• Od: 15-75mm
• Thinckness: 1-20mm
• Deform: Cold Drawn/Rolling
• Delivery Terms: EXW/Fob/CIF/CFR
• Length: 5-5.8 Meter
• Transport Package: Bundle
• Specification: under 75mm
• Trademark: bluesky pipe
• Origin: China
• HS Code: 7304319000
• Production Capacity: 50000 Ton/Year

Product Description

Product Description

Precision Steel Tube

A precision  steel tube is a hollow steel cylinder manufactured with high dimensional accuracy, tight tolerances, and excellent surface quality, typically through processes like cold drawing or cold rolling. These tubes are used in applications where exact fit, performance, and strength are critical, such as in hydraulic and pneumatic systems, the automotive industry, and aerospace. Common types include Drawn Over Mandrel (DOM), seamless (CDS/HRS), and welded (ERW), and it's available in round, square, and rectangular shapes. 

Key characteristics

Common types

Typical applications

High precision: They have very strict dimensional tolerances and are produced to tight specifications, which ensures precise fits and reduces leakage or failure.
Superior surface quality: The cold drawing or rolling process results in a smooth finish on both the inner and outer walls, reducing friction and wear.
Enhanced mechanical properties: The cold working process improves the tube's strength, hardness, and toughness, allowing it to withstand high pressures and loads.
Denser metal: The manufacturing process results in a denser metal structure compared to standard steel pipes.
Versatile: They are available in various materials (carbon steel, stainless steel) and shapes (round, square, rectangular) to suit different needs

Seamless tubes: Made by extruding a solid steel billet to create a hollow tube with no welded seam.
Welded tubes: Formed by rolling a steel sheet into a tube and welding the seam, such as Electric Resistance Welded (ERW).
Drawn-over-mandrel (DOM): A welded tube that is then cold-worked by being drawn over a mandrel. This process provides closer tolerances and a better surface finish compared to standard ERW tubing.
Cold-drawn tubes: Tubes that are mechanically worked at room temperature to improve their dimensional accuracy, strength, and surface finish. 
Alloy tubing: Includes types like 4140, which offer enhanced strength and other properties for more demanding applications. 

Hydraulic and pneumatic systems: Used to transport fluids and gases under high pressure.

Automotive industry: Essential for engine components, fuel injection systems, and exhaust systems.

Aerospace industry: Used in aircraft engines, landing gear, and hydraulic systems.

Construction and manufacturing: Used for structural components, machine parts, and equipment.

Other uses: Instrumentation, gas transmission, and manufacturing of components like bearings and conventional weapons

 Precision Seamless Steel tube

Applicable standard :ASTM A519/EN10305-1/EN10305-4/DIN 2391/GB3639/YB4675

Precision seamless steel tubes are high-precision, durable steel tubes manufactured without welds for applications requiring strength and accuracy, like hydraulic and pneumatic systems. They are produced from solid steel billets and then cold-drawn or hot-rolled to achieve tight tolerances, smooth surfaces, and uniform wall thickness. These tubes are used across industries such as automotive, oil and gas, and machinery, where their ability to withstand high pressure, corrosion, and stress is critical. 

Key characteristics
No welding seams: Manufactured from a solid billet, which creates a homogeneous structure with uniform strength and no weak points.
High precision: Manufactured to strict tolerances for inner and outer diameter, wall thickness, and surface roughness.
Superior strength and durability: They can withstand high pressure, corrosion, and stress without leaking or cracking.
Smooth surface finish: Reduces friction, making them ideal for hydraulic and pneumatic systems.
Versatile: Can be made from various carbon or alloy steels to meet specific performance requirements. 

Common applications
Hydraulic and pneumatic systems: Used for cylinders, valves, and other components where precise movement and high pressure are essential.
Automotive: Found in fuel injection systems, engine components, and vehicle control systems.
Oil and gas: Used in various applications where high pressure and corrosion resistance are required.
Machinery: Integral to heavy-duty and engineering machinery for their durability.
Shipbuilding: Utilized for robust and corrosion-resistant structures in marine environments

Production process
Seamless manufacturing: A solid steel billet is extruded or drawn through rollers to form a continuous tube with no weld seam.
Precision finishing: After initial production, tubes can undergo additional cold-drawing or hot-rolling to achieve the final high-precision dimensions and surface quality.
Quality control: Includes rigorous testing and inspection to ensure the finished product meets all specifications and is free from defects.

 Precision Welded Steel Tube

Applicable standard :EN10305-2/EN 10305-6/ASTM A513Type5 and 6/DIN2393/DIN2394/GB31315

Precision cold drawn or rolled welded tubes are high-precision steel tubes manufactured by welding steel strips and then cold-drawing them to achieve superior dimensional accuracy, smooth surface quality, and increased strength. In the United States, it is commonly referred to as a DOM tubing.These tubes offer tight tolerances (typically 0.015mm - 0.02mm) and minimal eccentricity, making them ideal for high-stress automotive, hydraulic, and mechanical applications.

Characteristics
Dimensions: Precise inside and outside diameters with limited wall thickness tolerances.
Surface Finish: Smooth, bright surface produced through cold drawing.
Strength: Increased hardness and mechanical properties due to cold forming.
Quality: Excellent concentricity and straightness

Manufacturing process
A flat strip of steel is formed into a tube using rollers.
The seam is then welded together.
The tube may undergo further processes, such as cold drawing, to achieve the desired precision and mechanical properties. 

Applications
Automotive: Used in shock absorbers, steering columns, and drive shafts.
Hydraulics: Ideal for hydraulic systems due to their strength and ability to withstand high pressure.
Mechanical Structures: Used in various structural components where precise dimensions are required.
Other industries: Also used in furniture, household appliances, fitness equipment, and various light engineering applications. 

Precision Shaped Tube

Applicable standard :EN10305-5/ASTM A513/ASTM A519/DIN 2395/GB3094

A precision shaped tube is a tube that is manufactured to have very tight tolerances and a specific cross-sectional shape, such as square, rectangular, or oval, in addition to standard round profiles. These tubes are used across industries like aerospace, automotive, and construction for their high strength, ability to reduce weight, and precise dimensional accuracy. 

Key characteristics
High dimensional accuracy: Precision tubes have tight tolerances, meaning their outer diameter, inner diameter, and wall thickness are held to very strict specifications.
Smooth surface finish: They often have a very smooth surface, which is crucial for many applications.
Consistent mechanical properties: The manufacturing process ensures consistent material properties, which is vital for performance under stress.
High strength and durability: While often lighter, these tubes are designed to be strong and durable, able to withstand extreme conditions.
Customizable: They can be produced to meet specific requirements, including specific shapes, dimensions, and material compositions. 

Production methods
Cold drawing: After initial shaping (like extrusion), tubes undergo a cold drawing process, which pulls them through a die to achieve more precise dimensions and a better surface finish.
Cold rolling: This process uses rollers to shape and size the tube, also contributing to its high precision and finish.
Heat treatment: Depending on the application, heat treatments like annealing may be applied to modify the material's properties. 

Common applications
Aerospace and defense: Used for lightweight, high-strength conduits, communication systems, and structural components.
Medical devices: Used in applications where precise dimensions and biocompatible materials are necessary.
Automotive: Employed in hydraulic systems, steering components, and other parts requiring high reliability.
Oil and gas: Used in demanding environments for transporting high-pressure fluids and chemicals, often requiring high corrosion resistance.
Chemical processing: Ideal for carrying corrosive chemicals because of their high durability and leak-proof nature.
Hydraulic and pneumatic systems: Widely used in the manufacturing of systems for fluid power. 

Tube/Tubular Precision straightening

We accept product customization, and we also have multiple forms to choose from for cutting steel pipes. After our processing, the straightness of our small-diameter tubular hollow  can reach 0.05mm, and they are mainly used as hollow shafts or roller for motors.

We also provide one-stop steel tube processing services, including honing, bending, and CNC machining

CNC deep hole honing machine

CNC pipe bending machine

CNC lathe and machining center

The hole diameter accuracy can reach above IT7 level, and the surface roughness can be up to Ra0.2μm 

Maximum bend diameter:∅70mm

Bending angle:190°

 Bending accuracy:±0.1°

Processing diameter  :∅100mm

Processing  length :650mm Positioning accuracy:0.001mm

Specification

Welded Tube:ASTM A513 Type  5 or EN 10305-2		Wall Thickness	1.5-6mm or 0.06-0.23 in.
Seamless Tube:ASTM A519 /EN10305 / DIN2391 / GB3639		Wall Thickness	1-14mm or 0.039-0.55 in.
Steel Grade	1010,1020,1035,1040,1340,1524,4130,4140, E195,E235,E275,E355,as customers' requirments
Package	Wooden case,Waterproof Woven Bag,as customers' requirments	Delivery time	25-40 days
Payment Term	T/T,L/C	Trade Terms	EXW,FOB,CFR,CIF
MOQ	1 ton	Surface Treatment	Oil,Phosphating,Polishing
Processing	Cold rolled/ Cold drawn
	1. BK (+C) : No heat treatment after last cold forming process.
	2. BKW (+LC): After last heat treatment there is a light finishing pass ( cold drawing)
	3. BKS (+SR): After the final cold forming process the tubes are stress relieve annealed.
	4. GBK (+A): After the final cold forming process the tubes are annealed in a controlled  atmosphere.
	5. NBK (+N):After the final cold forming process the tubes are annealed above the  upper transformation point in a controlled atmosphere.

ASTM A513 Type 5/A519;GB3639;EN10305;DIN2391
OD Size Range in.[mm]	OD		ID
0.500 to 1.699             [12.70 to 43.75]	0.005 [0.13]	0.000 [0.00]	0.000 [0.00]	0.005  [0.13]
1.700 to 2.099              [43.18 to 53.31]	0.006 [0.15]	0.000 [0.00]	0.000 [0.00]	0.006 [0.15]
2.100 to 2.499              [53.34 to 63.47]	0.007 [0.18]	0.000 [0.00]	0.000 [0.00]	0.007 [0.18]
2.500 to 2.899    [63.50 to 73.63]	0.008 [0.20]	0.000 [0.00]	0.000 [0.00]	0.008  [0.20]

Size tolerance
external diameter	Standard tolerance			Special tolerance
Outer Diameter	GB/T3639	DIN2391	EN10305	O D	thickness
4mm-20mm	±0.10 mm	±0.08 mm	±0.08 mm	±0.05mm	±0.05mm
20mm-30mm	±0.10 mm	±0.08 mm	±0.08 mm	±0.08 mm	±0.08 mm
31mm-40mm	±0.15 mm	±0.15 mm	±0.15 mm	±0.10 mm	±0.08 mm
41mm-60mm	±0.20 mm	±0.20 mm	±0.20 mm	±0.15 mm	±0.15 mm
61mm-80mm	±0.30 mm	±0.30 mm	±0.30 mm	±0.20 mm	±0.20 mm

Equivalent Material referance:
GB	TOCT	ASTM	BS	JIS	NF	DIN
10	10	1010,1012	045M10	S10C	XC10	C10,CK10
20	20	1020	050A20	S20C	XC18	C22,CK22
35	35	1035	060A35	S35C	XC35,C35	C35,CK35
45	45	1045	060A42\060A47	S45C	XC45	C45,CK45
15CrMo	15XM	A387 GR.B	BS1653	SCM415	15CD4	15CrMo5
20CrMo	20XM	4118	CDS110	SCM420	18CD4	20CrMo5
30CrMo	30XM	4130	1717COS110	SCM430	30CD4	25CrMo4
42CrMo	38XM	4140	708A42	SCM440	42CD4	42CrMo4
35CrMo	35XM	4135	708A37	SCM435	35CD4	34CrMo4
25Mn	25T	1025,1026	080A25,080A27			26Mn5
16Mn	14T2	SA414Gr.G	1633Gr.L	SPV32	A52C1	17Mn4/19Mn5
20Cr	20X	5120	527A19	SCr420	18C3	20Cr4
40Cr	40X	5140	530A40	SCr440	42C4	38Cr4/41Cr4
37Mn5		J55	EN46	NC-55E	38MS5	1.5122
40Mn2	40Γ2‌	1340		SMn438	40N5	42Mn6

FAQ

Q: Are you trading company or manufacturer?
A: We are professional manufacturer for steel pipes,and our company also is a very professional and technical foreign trade company for steel products. We have more export experience with competitive price and best after-sales service. Apart from this,we can provide a wide range of steel products to meet the requirement of customer.

Q:Will you delivery the goods on time?
A: Yes,we promise to provide best quality products and delivery on time no matter if the price change lot or not. Honesty is our company's tenet.

Q: Do you provide samples ? is it free or extra?
A: The sample could can provide for customer with free,but the freight will be covered by customer account. The sample freight will be returned to customer account after we cooperate.

Q: How can I get your quotation as soon as possible?
A: The email and fax will be checked within 24 hours,meanwhile,Wechat and WhatsApp will be online in 24 hours. Please send us your requirement and order information,specification(Steel grade,size,quantity,destination port),we will work out a best price soon.

Q: Do you have any certifications?

A: Yes,that's what we guarantee to our clients. we have IS09000,IATF16949 certinicate,ISO 14001 certificates etc.Our products are of high quality and we have professional engineers and development team.

Q: What is your terms of payment?
A:Payment<=1000USD, 100% in advance. Payment>=1000USD, 30% T/T in advance ,balance before shipmenit or paid against copy of B/L within 5 working days. 100% Irrevocable L/C at sight is favorable payment term as well.

Q: Do you accept the third party inspection?
A: Yes absolutely we accept.

Company Profile