
Annealed Pipe&Tube
Annealing represents a crucial delivery condition for precision steel tubes, commercially designated as GBK(+A) condition.
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Precision seamless steel tubes for automotive, hydraulic and machinery parts. Send Tenjan your drawing, tolerances, condition and inspection requirements.
Product Features & Specifications
Our precision tubes offer improved dimensional accuracy with outer diameter tolerance typically within ±0.05mm and wall thickness tolerance within ±0.03mm. The consistent straightness (≤0.5mm/m) and reliable roundness provide a solid foundation for subsequent manufacturing operations, helping to reduce initial machining time and material waste.
The superior surface quality with roughness levels reaching Ra≤1.6μm (and Ra≤0.8μm for premium grades) presents a clean, uniform surface finish that serves as an excellent starting point for further processing or coating applications. The absence of significant surface defects minimizes the need for extensive surface preparation before final machining or assembly.
Through controlled heat treatment processes including annealing, normalizing, and stress relieving, these tubes achieve balanced mechanical properties that can be tailored to specific application requirements. This flexibility allows customers to select the appropriate combination of strength, toughness, and machinability for their particular manufacturing needs.
Applications & Material Options
These precision tubes serve various industrial sectors including:
Automotive components: Shock absorber cylinders, steering shafts, and transmission parts
Hydraulic systems: Cylinder barrels and hydraulic line pipes
Mechanical parts: Shafts, sleeves, and structural components
Industrial equipment: General machinery and precision instrument applications
We offer multiple material grades including carbon steels and alloy steels, with the capability to provide stress-relieved, normalized, or annealed conditions according to your processing requirements. This ensures the tubes arrive in the most suitable condition for your specific manufacturing operations.
Quality Assurance & Service
Tenjan maintains comprehensive quality control throughout the manufacturing process, employing standardized testing procedures to ensure consistent product quality. Our technical support team provides professional assistance with material selection and processing recommendations based on your specific application requirements.
Backed by 21 years of manufacturing expertise, we deliver reliable tubular solutions through our advanced production capabilities and strict quality management system. Our established logistics arrangements ensure reliable delivery, while our technical guidance and after-sales support provide continuous assistance throughout your manufacturing process.
Custom Sizes OD10-108mm-ASTM/EN/DIN/JIS/GOST Certified -Small-Batch Friendly
| Parameter | Key Features |
| Outer Diameter | 10-108mm (0.39″-4.25″) • Fully customizable |
| Wall Thickness | 1-20mm (0.039″-0.79″) • ±0.1mm precision tolerance |
| Material | Carbon Steel • Alloy Steel • Special grades available |
| Process | Cold Drawn Cold Rolled for superior finish |
| Standard | Typical Grades We Supply |
|
GB |
DT4,Y15,10#,20#,20G,Q235,25Mn,35#,45#,55# 16Mn,Q345B(Q355B),Q345C(Q355C),Q345D(Q355D),Q345E(Q355E),Q420,Q460,20Cr,40Cr, 15CrMo,20CrMo,30CrMo,35CrMo,42CrMo,20CrNiMo,40CrNiMo,20CrMnTi,20Mn2,40Mn2,40MnB,35MnB, 35Mn15CrMn,20CrMn,20CrMnMo,38CrMoAL,36Mn2V,38Mn2V,40MnMoV,15Mo3,16Mo3,31CrMoV9 |
|
ASTM |
1215,1008,1010,1020,A105,A106 Gr.B,A36,1026,1035,1045,1055,SA179,SA192 Gr·50,Gr·55,Gr·65,5120,5140,4130,4135,4140,8620,4340,SAE 5120,1524,1340,15B41,SAE5115,SAE 5120,SCM23 |
| EN | DC01,11SMn30,P235TR1,P195GH,P265TR2,E235 E355,ST52,S355JR,S355JO,S355J2,S355NL,S420N,S420NL,S460NL,20Cr4, 41Cr4,13CrMo4-5,20CrMo4,25CrMo4,34CrMo4,42CrMo4,20NiCrMo2,34CrNiMo6,20MnCr5, 22Mn6,42Mn6,42MnB4,34MnB5,37Mn5,16MnCr5,20CrMo5. |
| JIS | SUM22,S10C,STKM11A,STPT370,STB35,S20C,STKM12,STKM13,STPT410,STB42,SS400,S35C,S45C,S55C SCr22,SCr440,SCM415,SCM420,SCM430,SCM435,SCM440, SNCM220,SNCM439,SMnC420H,SMn420,SMn438, SMnC420H |
| DIN | DC01,11SMn30,CK10,C10,ST35.8,C20,CK20,ST45.8,St37,S235JR,C26D,CK35,CK45,CK55 |
| GOST |
08КП,10,20,Ст3сп,25,35,45,5515Г2, 09Г2C/10Г2C1,15Г2,14Г2С,C355,20Х,40X,15XM,20ХМ,30ХМ,35ХМ,38ХМ,20ХНМ,40ХНМ,20ХГТ,20Г2,40Г2,18ХГ,20ХГМ |
| Other Speical Grades can be customized | |
| Industry | Key Applications Parts | Relevant Standards | Our Advantages |
| General Structural | Square Rectangular Tubes | GB/T 3094,ASTM A500, EN 10210 |
Good Surface,lightweight,precision dimensions (±0.1mm) |
| Automotive and Motorcycle Component | Shock Absorbers,Steering Systems,Thrust Rods | EN 10305-1,JIS G3445, DIN 2391,ASTM A519 |
High fatigue strength,High yield strength,lightweight, precision dimensions (±0.1mm) |
| Engineering and Mining Support | Anchor Bolts,Support Pipes,Hydraulic Props | ASTM A519,DIN 2391, JIS G3441,EN 10297-1, ISO 10799 |
High Strength Yield Strength High Elongation Customization Service – Special steel grades, dimensions and surface treatments available according to project requirements |
| Construction Machinery | Drive shaft sleeves,Gearbox Guide Tubes,Crane Boom Guide Tubes,Excavator Arm Tubes,Loader Frame Tubes,Arctic Low-Temperature Tubes | ASTM A519,DIN 2391, JIS G3445,EN 10210-1, GOST 8733, ASTM A106,ISO 9329 |
ID/OD tolerances of ±0.05mm. Wall thickness uniformity straightness ≤0.5mm/m |
| Fluid Transport Systems | Oil/Gas pipelines,chemical systems,Power/Energy | ASTM A106 Gr.B, EN 10216-2,GOST 8734 |
Eddy Current + Ultrasonic Testing,Hydrostatic Testing |
| High-Pressure Boilers | Superheaters,Steam lines,Reheaters,Economizers) | ASTM A192,DIN 17175, EN 10216, JIS G3461/G3462 |
Enhanced material density through cold-drawing/rolling ensures long-term stability Full Compliance with Int’l Standards,Superior Creep Fatigue Resistance |
| Geological Drilling | Drill Pipe,Tubing | ASTM A519,API 5DP, EN 10208-2 |
High Strength Wear Resistance precision Dimensions Impact Fatigue Resistance |
| Agricultural Machinery | Hydraulic cylinders,drive shafts,Lift arms,steering housings,Boom frames | ASTM A519,EN 10210-1, DIN 2391,GOST 8733, JIS G3445 |
Material Advantages:High Strength Lightweight,Precision Cold-Drawing Technology,Dimensional accuracy ±0.05mm |
| Petroleum Cracking Units | Reformer Tubes,Heat Exchanger Tubes,Reactor Feed Pipes,Transfer Lines,Quench Oil Pipes | ASTM A335,ASTM A213, EN 10216-2 |
Optimized Material Purity,Precision Dimensional Control,Customized Solutions |
Tailored Features · Designed Exclusively for Your Needs

Alloy Steel Material and Process Planning Material Sourcing Review:
For each order, confirm the material grade, dimensions and acceptance requirements:
✔ 100+ Custom Alloy Grades– Chemistry control (C, Cr, Ni, Mo adjustments)
✔ Engineered Mechanical Properties -Yield/Tensile strength customization
✔ Industrial-Grade QC-Full-spectrum testing (UT, hardness, dimensional)
✔ Project-Specific Cost Review-Compare grade, order quantity and downstream processing requirements
Application:Oil & Gas, Automotive, Heavy Machinery, Energy

Extra-Long Piercing + Automated Normalizing Furnace – Precision Alloy Steel Tubes for High-Stress Applications Heating and Delivery Condition Review:
Review billet heating and normalizing requirements for alloy steel tubes, and agree the delivery condition and acceptance criteria before production.
Normalizing Requirements to Confirm:
✔ ±2°C Precision Control–Confirm the temperature-control requirement
✔ Mechanical Property Review–Specify strength and fatigue-related acceptance requirements
✔ Batch Consistency Checks–Confirm heat and batch traceability
Key Industries Served:Oil & Gas, Power Generation, Automotive, Geological Drilling, Mining Support and Construction

Tube Straightening – Confirm Requirements Before Machining Straightness and Machining Review:
Confirm the required straightness, including the stated ≤0.5mm/m value, against the component drawing and agreed inspection method:
✔ Machining Preparation– Confirm straightness and machining allowance for the component
✔ Cutting Tool Selection – Select cutting conditions for the supplied grade and hardness
✔ Production Planning –Review material allowance, handling and scrap criteria
Production and Inspection Review:
Process Review – Confirm the production route and inspection records
Automated QC – Real-time straightness monitoring
Custom Solutions– Optimized for alloy steel grades
Key Applications: Hydraulic Cylinders, Oil & Gas, High-Performance Automotive (drive shafts, suspension components)

Ultrasonic + Eddy Current Dual Testing – High-Reliability Inspection for Alloy Steel Tubes
Advanced NDT System Features:
✔ Ultrasonic Testing (UT)– Detects internal flaws down to 0.20mm
✔ Eddy Current (ET)– Identifies surface/subsurface defects
✔ Multi-Probe Technology– Confirm ID/OD/wall coverage
Quality Assurance:
Inspection Acceptance Criteria(agree the method, reference standard and acceptance level)
Dimensional Control– ±0.05mm OD tolerance
Material Verification– Full composition check
Application Review: Oil & Gas, Energy, Automotive
Tell us the material grade, outer diameter, wall thickness, quantity and end-use requirements.
Contact Our Team