Description
ASTM A312 is the standard specification for seamless, straight-seam welded, and heavily cold-worked welded austenitic stainless steel pipe intended for high-temperature and general corrosive service. It covers various grades including TP304, TP316L, and TP321. The pipes must conform to strict chemical compositions and mechanical requirements, such as tensile and yield strength. Standardized testing, including grain size determination, weld decay tests, and non-destructive hydrostatic or electric tests, ensures structural integrity. This specification is essential for ensuring the durability and safety of piping systems in chemical, petrochemical, and power generation industries.

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Main Process Steps

1. Raw Material & Piercing (原料与穿孔)
Starting with premium round solid bars, we perform precision drilling to create high-quality hollow bars as the foundation for our seamless pipes.
2. Cold Rolling & Drawing (冷轧与冷拔成型)
Advanced cold forming technology is applied to achieve the exact outer diameter and strict wall thickness tolerances required by ASTM A312.
3. Heat Treatment & Pickling (热处理与酸洗)
Tubes undergo solution annealing to restore the austenitic microstructure, followed by straightening and pickling for maximum corrosion resistance.
4. Strict Quality Inspection (严格质检与定尺)
Every pipe is cut to the final length and subjected to rigorous 100% NDT (Non-Destructive Testing) and Hydrostatic testing to ensure zero defects.
5. Secure Packaging & Shipment (安全包装与发货)
Finished pipes are securely packed in seaworthy plywood boxes or woven bags, ready for safe global delivery to your project site.

Quality Control
1. Dimensional check
2. PMI
3. Thickness ultrasonic measurement
4. Tensile test
5. Eddy current test
6. Ultrasonic test
7. Hydrostatic test
8. Intergranular corrosion test
9. Impact test
10. Grain size
11. Metallographic
12. Hardness test

Applications in the industries.
1) Oil & Gas
2) Chemical & Petrochemical
3) Power Generation
4) Marine & Seawater Desalination
5) Aerospace & Defense
6) Food & Beverage
7) Pharmaceutical
8) Water Treatment

Why Choose us?
1. Sufficient inventory
a) We have a large inventory of materials and sizes, such as 304, 304L, 316L, 321, 310s, etc., from small to large sizes. We have about 2,000 tons of these in our warehouse to prepare for customers’ urgent orders.
2. Professional production
a) Using advanced domestic and international production equipment, and relying on our mature processes and skilled workers, we produce products that meet standards and customer order requirements.
3. Guaranteed delivery date
a) With a sufficient number of production equipment, production efficiency is greatly improved, and with the addition of inventory reserves, orders can be completed within the specified time.
4. Quality Assurance
a) Professional testing personnel and advanced testing equipment strictly control the quality of products, ensuring that the products are qualified and issuing a 3.1 material report to prevent problems in customers’ projects.

Frequently Asked Question (FAQ)
Q1. What is your minimum order quantity?
A: It depends on the inventory. If there is inventory, we can sell any one unit. If there is no inventory, the minimum production quantity is generally 1 ton.
Q2. What are your payment methods? How can I trust you?
A: We accept a letter of credit at sight or a 30% prepayment. The remaining balance can be paid after the goods have been inspected and approved before shipment.
Q3. Are your products inspected before shipment?
A: All products undergo dimensional inspection before shipment to ensure that the tolerances are within the acceptable range (100% PMI), and each piece is subjected to non-destructive testing to guarantee quality.
Q4. How should the product be packaged?
A: No special requirements. We can use woven fabric packaging with plastic lids, or wooden crates, wooden frames, or iron frames according to your needs.

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