GB/T 8162 25MnCr6 High-Strength Low-Alloy Seamless Pipe for Structural Use

Material Introduction

The “GB/T 8162 25MnCr6” refers to a seamless steel tube designated under the Chinese national standard GB/T 8162 (for structural use) that is made from a low-alloy, high-strength steel with nominal chemical designation “25MnCr6.” The alloying with Mn (manganese) and Cr (chromium) (and possibly additional trace elements) is intended to provide enhanced strength, toughness, and overall mechanical performance compared to plain carbon steels.

Specifications

• Standard: GB/T 8162-2018 (implements from 2019-02-01)

• Shape / Form: Round seamless tube

• Outer Diameter / Wall Thickness: As per GB/T 17395 tolerances on diameter and wall thickness, with special allowances for hot-rolled vs cold-drawn.

• Delivery Status: Hot-rolled (expanding) or cold-drawn (rolled), with possible heat treatments (annealing, normalizing, tempering) depending on negotiated contract.

• Dimensional Tolerances: Tolerances for outer diameter, wall thickness, out-of-roundness, and end squareness as per GB/T 8162 / GB/T 17395.

Chemical Composition

Mechanical Properties

Major Features

• High strength-to-weight: The alloying with Mn and Cr allows the pipe to offer higher strength than plain carbon structural tubes, enabling lighter designs.

• Good toughness and ductility: With appropriate heat treatment, the material can maintain acceptable toughness and elongation for structural service.

• Better hardenability and fatigue resistance: The alloying elements help delay crack initiation and propagation under cyclic loads.

• Weldability and fabricability: Although alloyed, with controlled carbon equivalent and proper preheating/heat input, the steel can be welded and processed much like structural steels.

• Consistency and reliability: As a seamless pipe, it avoids the weld seam issues of welded tubes and ensures uniform grain structure and performance in radial direction.

Applicable Standards

Here are relevant standards (international and regional) that are comparable or sometimes referenced in structural seamless tubes:

• GB/T 8162-2018 — Seamless Steel Tubes for Structural Purposes

• GB/T 17395 — Dimensions, shapes, weights and tolerances for seamless steel tubes

• ASTM A572 / A992 — High-strength, low-alloy structural steels

• EN 10210 (Parts 1, 2, 3) — Hot-finished structural hollow sections (non-alloy and fine-grain steels, also high-strength/weather-resistant versions)

• ISO / EN / JIS / Russian GOST equivalents (not directly for 25MnCr6 but in the domain of structural seamless tubes)

• If the user’s contract calls for impact testing, dimensional tolerances, or non-destructive testing (e.g., ultrasonic, eddy-current), those are also to be referenced from the standard’s test & inspection clauses in GB/T 8162.

Application Domains

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.