Shock Absorber Tube Carbon Steel Cold Drawn Bright Precision Welded Tube For Automotive

Material

This product is a carbon steel cold-drawn, bright, precision-welded tube designed for automotive applications — specifically for use as a shock absorber cylinder or related structural/hydraulic components. The tube is produced by forming (welding) a pre-tube shell (often ERW welded) followed by precise cold drawing (and optionally straightening) to achieve tight tolerances, excellent surface finish, and superior dimensional control. It combines the cost-effectiveness of welded construction with the high precision and mechanical properties of cold-drawn processing.

Specification

• Process: Welded (ERW or similar) shell + cold draw finish (bright, precision welded)

• Outer Diameter (OD): typically customizable, for example from ~10 mm up to ~400 mm depending on application

• Wall Thickness (WT): typically from ~1 mm to ~35 mm (or more) depending on design

• Length: up to ~12 000 mm (or per customer request)

• Surface: Bright (cold-drawn finish), polished straightness, minimal deformation, controlled weld seam

• Tolerance: Tight tolerances on OD, WT, straightness and concentricity as per precision tube standards (e.g., EN 10305-2)

Key Features

• High dimensional accuracy: The cold-drawn process enables very tight outer diameter, inner diameter, and wall thickness tolerances.

• Smooth bright surface finish: Cold drawing produces a high quality surface finish (inside and outside) with reduced roughness, beneficial for hydraulic and shock absorber applications.

• Improved mechanical properties: Cold forming (drawing) increases strength and improves micro-structure compared to hot-finished or plain welded tubes — giving better yield, tensile strength, and fatigue resistance, which is critical for automotive shock absorber use.

• Good weldability and cost-effectiveness: Using welded shell plus cold draw rather than full seamless reduces cost while still achieving precision properties suitable for automotive structural/hydraulic parts.

• Automotive-specific performance: The tube design supports required straightness, concentricity, and fatigue life needed for shock absorber cylinders and structural hydraulic parts in vehicles.

Our Advantages

As a factory-based manufacturer specializing in cold drawn bright precision welded tubes for automotive applications, we offer distinct advantages:

• We strictly control straightness and concentricity: For tubes with OD > 15 mm and lengths > 1,000 mm, the deviation from straightness under EN 10305-2 must not exceed 0.0015 × L when yield strength ≤ 500 MPa, or 0.002 × L when yield > 500 MPa.

• We offer tight tolerances on outer diameter and wall thickness, in line with standards like GB/T 24187-2023.

• We ensure optimized mechanical properties through cold-drawing process, including a refined micro-structure, better strength and fatigue life compared to standard welded tubes.

• We guarantee material traceability and inspection: full chemical analysis, tensile testing, NDT or leak-tightness testing as required by standards such as EN 10305-2.

• We provide flexibility in engineering and customization: Our facility supports custom diameters, lengths, wall thicknesses, surface finishes, and delivery conditions (e.g., +C, +SR, +N) to match shock absorber or hydraulic cylinder manufacturer requirements.

• We focus on the automotive supply chain: We understand the requirements of shock absorber cylinders (straightness, fatigue resistance, surface quality, weld seam control) and design the tube accordingly for enhanced assembly performance and longer service life.

Chemical Composition

Below is a table summarizing chemical composition of five similar grades commonly used for cold drawn precision welded tubes for automotive/hydraulic applications:

Mechanical Properties

Here are mechanical performance examples for the five grades under typical delivery conditions (+C, +LC, +SR, +N) in accordance with standard EN 10305-2:

Standards Executed

• Chinese standard: GB/T 24187-2023 “Cold-drawn precision single welded steel tubes” for applications including automobile industry.

• European standard: EN 10305-2 “Steel tubes for precision applications – Technical delivery conditions – Part 2: Welded cold drawn tubes” (grades E155, E195, E235, E275, E355)

• Other relevant standards: JIS G3445 (machine structural carbon steel tubes), DIN 2393/2394 (cold drawn precision tubes)

Application Areas

General Application Area

This precision tube product targets the automotive and hydraulic systems market, especially for use in shock absorbers, hydraulic cylinders, and structural tubular parts where precision, strength and surface quality matter.

Specific Use-Cases in That Field

• As the inner or outer cylinder for a shock absorber in vehicles: requiring tight OD/WT tolerances, straightness and fatigue resistance.

• As hydraulic piston or rod tube for automotive/semi-truck hydraulic systems: needs smooth inner finish, dimensional accuracy and high strength.

• As structural tubular component within the suspension or steering system (e.g., steering column tube, axle sleeve) where concentricity, weld seam quality and mechanical strength are critical.

• In telescopic cylinder assemblies (for example in commercial vehicles, lifts) needing bright finish and high dimensional control to reduce friction and enhance life.

Q: Are you trading company or manufacturer ?

A: manufacturer,also can do trading.

Q: How long is your delivery time?

A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock,

it is according to quantity.

Q: Do you provide samples? is it free or extra ?

A: Yes, we could offer the sample for free charge but need pay the cost of freight.

Q: What is your terms of payment ?

A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.

If you have another question, pls feel free to contact with me.