• undefined
  • undefined
  • undefined
  • undefined

321 Stainless Seamless Tube

321 Stainless Seamless Tube exhibits high strength, resistance to oxidation peeling and subsequent stability against aqueous solution corrosion in a temperature range up to approximately 900 degrees Celsius.It can be bent , no annealing after welding. It has excellent toughness even at low temperatures.


Seamless Tube

321 Stainless Seamless Tube


Product Details

Product details

321 Stainless Seamless Tube  exhibits high strength, resistance to oxidation peeling and subsequent stability against aqueous solution corrosion in a temperature range up to approximately 900 degrees Celsius.It can be bent , no annealing after welding. It has excellent toughness even at low temperatures.

The process of the stainless seamless steel tube product determines its limited performance. Generally, the seamless steel pipe has low precision: uneven wall thickness, low brightness inside and outside the pipe, high fixed-length cost, and pitting and black spots on the inside and outside, and its detection; Shaping must be processed offline. Therefore, it embodies its superiority in high-pressure, high-strength, mechanical structural materials.




200 series 300 series 400 series

Model Number

202, 203, 301, 302, 304, 304L, 309,310,316, 316L, 321, 410, 416, 420, 430, 440



Out Diameter

6-630 mm or Customizable

Wall Thickness

1-40mm or Customizable


3-12m or Customizable


welded, seamless


Round,Square, Rectangle


Hot Rolled , Cold Rolled

Surface treatment

Polish Anneal Pickling Bright

Surface Finished

NO.1, NO.2D, NO.2B, BA, HL, 8K, Mirror, or as required



Price Term:



30% paid for deposit by T/T before production arranged,the balance to be paid before shipment, L/C at sight or request.


Free provided

Sample time

2-3 days


1 ton , We can accept sample order.

Place of origin



Standard export seaworthy package, water proof paper + wooden pallet or as required.

Delivery time

Prompt delivery , 7-15 days after deposit, or as the order quantity.


Building, Construction, Food, Industry, Chemistry, Agriculture, Mechanical, Medical, Devices, etc

Stainless steel refers to the air, steam, water and other weak corrosion medium and acid, alkali, salt and other chemical corrosive medium corrosion of steel, also known as stainless acid-resistant steel. Stainless steel wire drawing is the texture of stainless steel surface like silk, this is just a kind of processing technology of stainless steel.

The surface is matte, carefully look at the above a trace of texture, but can not touch out. It is more wear-resistant than general bright stainless steel and looks more advanced

Our Advantages:
(1) High quality stainless steel sheet with reasonable price.
(2) Every process will be checked by responsible QC which insures every product’s quality.
(3) Professional packing teams which keep every packing safely.
(4) Free samples can be provided as your requirements.
(5) Wide excellent experiences with after-sale service.

Grades C max Mn max P max S max Si max Cr Ni max Mo
304 0.08 2.00 0.035 0.03 1.0 18.00-20.00 8.00-11.00 /
304L 0.03 2.00 0.045 0.03 1.0 18.00-20.00 8.00-12.00 /
316 0.08 2.00 0.035 0.03 0.075 16.00-18.50 10.00-14.00 2.00-3.00
321 0.08 2.00 0.045 0.03 1.00 17.0-19.0 9.0-12.0 /


Product Description

Stainless steel seamless pipe is a hollow long round steel, mainly widely used in petroleum, chemical, medical, food, light industry, mechanical instrumentation and other industrial pipelines and mechanical structural components. In addition, when the bending and torsional strength are the same, the weight is lighter, so it is also widely used in the manufacture of mechanical parts and engineering structures. 

Stainless steel seamless pipe is a kind of hollow section, no joints around the strip of steel. The thicker the wall thickness of the product, the more economical and practical it is, the thinner the wall thickness, its processing costs will rise substantially.

Product Parameters


 Products Standard

Executive Standards


Stainless Steel seamless steel pipe


Stainless steel seamless steel tubes for fluid transport


Stainless steel seamless steel tubes for construction


Stainless steel seamless steel tubes for boilers and heat exchangers


(GJB2296-95)(YB678-71) stainless seamless steel pipe for aviation


(GJB2608-96)(YB676-73) Structural steel thick wall seamless steel pipe for aviation


(YB/T679-97)(YB679-71) 18A hollow rivet thin wall seamless steel pipe for aviation


(GJB2609-96)(YB680-71) structural thin wall seamless steel pipe for aviation


(YB/T681-97)(YB681-71) Aviation conduit 20A thin wall seamless steel pipe


GB3090-82 Stainless Steel small diameter steel pipe


Seamless steel tube for high pressure boilers


GB3087-82 Low and medium pressure seamless steel pipe


GB3089-92 stainless acid resistant ultra-thin wall seamless steel pipe


GB9948-88 petroleum cracked seamless steel pipe


Seamless Ferritic and Austenitic alloy Steel Tubes for boilers and heat exchangers



Stainless steel pipe is an economic section steel, is an important product in the steel industry, can be widely used in life decoration and industry, many people on the market for the production of stairs handrails, window guards, railings, furniture, etc.. Commonly available in 201 and 304 two materials.

Accounting for about 8% a 16% of all steel, it is used in an extremely wide range of applications in the national economy. Because of the steel pipe has a hollow section, and therefore the most suitable for liquid, gas and solid transport pipeline; at the same time with the same weight of round steel, steel pipe section coefficient, bending and torsional strength, so also become a variety of machinery and building structure on the important material. Structures and components made of stainless steel tubes have a larger cross-sectional modulus than solid parts under equal weight. Therefore, the stainless steel tube itself is a metal-saving economic section steel, it is an important part of efficient steel, especially in the oil drilling, smelting and transport industries are in greater demand, followed by geological drilling, chemical industry, construction industry, machinery industry, aircraft and automobile manufacturing, as well as boilers, medical equipment, furniture and bicycle manufacturing also need a large number of various steel tubes. With the development of new technologies such as atomic energy, rockets, missiles and space industry, stainless steel pipe in the defense industry, science and technology and economic construction is becoming more and more important.

Stainless steel pipe is safe, reliable, sanitary and environmentally friendly, economical, thin-walled pipes and new reliable, simple and convenient connection methods are developed successfully, so that it has more irreplaceable advantages of other pipes, the application of engineering will be more and more, the use of more and more popular, the prospects are good.

As stainless steel has many of the ideal properties required for building materials, it can be said to be unique in the metal, and its development continues. To make stainless steel perform better in traditional applications, improvements have been made to the existing types, and new stainless steels are being developed to meet the stringent requirements of advanced architectural applications. Due to increasing production efficiency and improving quality, stainless steel has become one of the most cost effective materials chosen by architects.

Stainless steel combines performance, appearance and use characteristics, so stainless steel will remain one of the world's best building materials.

With the implementation of China's reform and opening-up policy, the national economy has gained rapid growth, urban residential, public buildings and tourism facilities are built in large numbers, the hot water supply and domestic water supply has put forward new requirements. In particular, the issue of water quality is becoming more and more important and the requirements are increasing. Galvanized steel pipe, a common pipe because of its easy corrosive, under the influence of relevant national policies, will gradually withdraw from the historical stage, plastic pipe, composite pipe and copper pipe into the common pipe of the piping system. But in many cases, stainless steel pipe is more superior, especially the wall thickness of only 0.6 ~ 1.2mm thin-walled stainless steel pipe in high-quality drinking water system, hot water system and will be safe, sanitary water supply system in the first place, with safe and reliable, health and environmental protection, economic and other characteristics. Has been proven by domestic and foreign engineering practice is the best comprehensive performance of the water supply system, new, energy-saving and environmentally friendly pipe, is also a very competitive water supply pipe material, will play an incomparable role in improving water quality, improve people's living standards.

In the building water supply system, as galvanized steel pipe has ended a hundred years of glorious history, a variety of new plastic pipes and composite pipes have been rapidly developed, but a variety of pipes still have some shortcomings to varying degrees, far from fully adapt to the needs of the water supply system and the country's requirements for drinking water and related water quality. Therefore, the relevant experts predict that the building water supply pipe material will eventually return to the era of metal pipe. According to foreign application experience, in the metal pipe identified thin-walled stainless steel pipe as one of the best overall performance of the pipe.

Grade and classification of stainless steel surface treatment


Code of surface


Summary of manufacturing method


Primary surface


Silvery white without luster

A surface treated with heat treatment and pickling after hot rolling.

Industrial tank, chemical industrial equipment, etc., thick 3.0MM-10.0MM. It does not need to have a glossy surface

Blunt surface


A slightly lustrous silvery white

Hot rolling + annealing shot peening acid first + cold rolling + annealing pickling

Used for deep stamping, such as automotive components, water pipes, etc. General materials, deep drawing materials

Fog surface


Silver and better than 2D surface gloss and flatness, 0.39 micron roughness

Hot rolling + annealing shot peening + cold rolling + annealing pickling + tempering rolling. After NO.2D treatment, the final mild cold rolling is carried out by polishing roller

Such as tableware, building materials and so on. With improved mechanical properties of the surface treatment, almost all applications.

Frosted surface


Has a better gloss, with discontinuous coarse grain.

Use 100-120 grinding strip to grind out the product

Used for interior and exterior decoration materials, electrical products and kitchen equipment, etc.

Frosted surface


Better gloss, with discontinuous coarse lines, stripes thinner than NO.3.

With particle size 150-180 grinding belt grinding out the product

Used for bath, interior and exterior decoration materials, electrical products, kitchen equipment and food equipment, etc.

Frosted surface


Better gloss, with discontinuous coarse lines, stripes thinner than NO.4.

The product is ground with the 240 grinding belt

Used for bath, interior and exterior decoration materials, electrical products, kitchen equipment and food equipment, etc.

Frosted surface


Has a better gloss, with discontinuous coarse grain

The product is ground with the 320 grinding belt

Building materials, kitchen utensils

Frosted surface


Has a better gloss, with discontinuous coarse grain

The product is ground with the 400 grinding belt

Building materials, kitchen utensils, food equipment, etc

Drawing surface


Silvery gray with hair streaks. 2D or 28pcs are polished with a suitable abrasive material to make the surface continuously abrasive

A product with a continuous abrasive pattern produced by the continuous grinding of an appropriately sized polished strip (subdivision 150-320)

Mainly used for architectural decoration, elevator, building doors, panels and so on.

Bright surface


Excellent surface gloss and high reflectivity.

Usually bright and fire surface processing, surface reflection is very high.

Used in household appliances, mirrors, kitchen equipment, decorative materials, etc

mirror surface


It's not much worse than a mirror

Rough lapping

Mirrors, decorative panels

mirror surface



Grinding and polishing

Mirrors, decorative panels


Pack and Ship





Customer Evaluation

Over the years, we strive for survival by quality and development by efficiency, adhering to the business philosophy of "integrity, pragmatism, innovation and development", and have repeatedly won praise from customers.



Are you a manufacturing company or a trading company?


We are a manufacturer of metal materials and products with many years of experience.


Can you provide samples?


We can provide free samples, but samples are subject to a sample fee, which is refundable upon order confirmation.


How can I get an accurate quotation?


Please provide the product standard, material, size, quantity and other information.


What kind of payment terms do you accept?


We can accept T/T, L/C, Western Union or negotiation.


What markets do you mainly sell to?


Australia, America, Asia, Middle East, Western Europe, Africa, etc


Can you deliver the goods on time?


Yes, whether the price changes or not, we guarantee to provide the best quality products and on time delivery. Integrity is the purpose of our company.

< 12 >


Shandong Zhongyi Metal Products Co., Ltd. is an enterprise specializing in the research and development, production, sales and service of metal products. Located in Shandong Province, China, the company covers a vast area with advanced production equipment and testing instruments, and a team of skilled and strong staff.

Zongyi Metal Products Co., Ltd. mainly produces all kinds of metal products, serving the industries of precision machinery parts, automobile parts, electronic components, construction and decoration materials. Adhering to the business philosophy of "Quality is the foundation, Innovation is the soul", the company constantly introduces advanced technology and equipment to improve product quality and reduce production costs to meet customer needs.

We have rich experience in the metal products industry, and our products sell well in domestic and international markets and are well received by customers. We always adhere to the customer-centered, market-oriented, in order to survive, innovation and development. We are willing to cooperate with customers at home and abroad to create a better future.









Series Related Products