Brief introduction of stainless steel seamless pipes

Brief Introduction of Stainless steel seamless pipes and Tubes

Stainless steel seamless pipes and tubes play very important role in various industries today. Seamless stainless steel tubes are made from stainless steel round billets by hot processing such as hot rolled, hot extruded, or cold processing such as cold rolled and cold drawn. For hot finished seamless pipes, the round billets are hot piercing, and hot rolled to specific sizes, or hot extruded to specific sizes. While for cold finished seamless pipes, The round billets are made to mother tubes by hot piercing, and then the mother tubes are made to specific size of seamless stainless steel seamless tubes by cold rolling or cold drawing. Generally speaking cold finished stainless steel seamless pipes have more advantages than hot finished. Here below are the main advantages: better mechanical properties (such as better strength, elongation, hardness), better corrosion resistance, higher dimension accuracy, and wider size range.

The most popular size of stainless steel seamless pipes and tubes are with 2 mm - 508 mm outside diameter and 0.50 mm - 50 mm wall thickness. which also includes a wide range of sizes in duplex and super-duplex stainless steels grades. Tubes with outside diameter below 6 mm, people usually call them capillary tubes. And seamless stainless steel tubes with thick wall thickness are usually used for high pressure applications, one of the most popular applications is as hydraulic tubing. 316L stainless steel hydraulic tubing is very popular for hydraulic systems.

Here below are the detailed specifications of stainless steel seamless pipes:
1) Standard

Seamless stainless steel tubes are available according to below standards, also on customer's requirements.
- EN 10216-5 TC1 / TC2, EN 10297-2, PED 97/23/EC, AD 2000,     
- ASTM A312/312M, A213/213M, A269, A789, A790, A999, A632, A511...

2) Most popular steel Grades
Austenitic stainless steel grades: 1.4301/1.4307, 1.4401/1.4404, 1.4541/1.4878, 1.4571, 1.4948; 304/304L, 316/316L, 316Ti, 317/317L, 321/321H, 304H, 347/347H, 310/310S
Grades of Duplex /super duplex pipes: 1.4462, 1.4410, 1.4539; S32205, S31803, S32750, S32760, 904 /904L.

3) Delivery condition
Seamless stainless steel tubes mainly are delivered in below conditions:
- Solution annealed and pickled,

- Tubes delivered in Bright annealed condition as Stainless steel bright annealed tube.
- Annealed and Polished

4) Tolerance:

According to D3/T3, D4/T4, EN 10305-1 or corresponding standards; Seamless stainless steel tubes can be supplied with high precision dimension tolerance as precision tubes. One of the typical type of tubes and pipes with precision dimensions is instrumentation tubing.

5) Size range & Lengths

OD: 2 mm to 508 mm

WT: 0.5 mm to 50 mm. 

Length: Most popularly stainless steel seamless pipes are supplied with straight length up to 25 meters, and supplied as u bend pipes for some kind of Stainless steel heat exchanger tubes and seamless stainless steel tubes can also be supplied in coils as seamless coiled tube.

6) Applications:

Stainless steel seamless pipes not only used as General fluid line pipes, but also as tubing and piping, components widely used for corrosion resistant, erosion and heat-resistant applications in chemical engineering, chemical fertilizer, chemical machinery, oil refining, petroleum, smelt, medical machinery, paper making, Heat preservation and refrigeration, mechanical equipment, food, electricity, water conservancy, architecture, aerospace, navigation shipbuilding, boiler heat exchanger, environmental protection, and so on.