Your Professional Steel Pipe Supplier
Founded in 1999, Henan Shuangzhong Intelligent Technology Co., Ltd. has focused on precision manufacturing and industrial piping systems for over two decades. It is a comprehensive piping equipment manufacturer integrating R&D, production, customized processing, and overall solution provision. The company boasts a mature production system, a strict quality control system, and strong flexible customization capabilities, continuously providing global industrial customers with high-precision, high-stability, and highly adaptable piping and fitting products.
Unlike ordinary single-manufacturer companies, we can customize various standard and non-standard piping fittings and complete sets of equipment according to customer operating conditions, media, parameters, and usage scenarios, widely adaptable to complex working conditions such as chemical, fluid transportation, mechanical support, and industrial assembly.
Whether it's mass production of standard products, customization of complex non-standard precision parts, or complete piping system solutions, we can provide one-stop solutions, simplifying customer procurement and coordination processes and efficiently facilitating project implementation.
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310S Stainless Steel Pipe1.Type:Seamless, Welded2.OD:1/2-483.Thickness:SCH5-SCHXXS4.Length:0-12M, Customized5.Process:Hot/Cold Rolled,Hot work,Cold drawn
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ASTM A312 TP321 Seamless Stainless Steel PipeMaterial Standard: ASTM A312Grade No.: TP321Type: Seamless welded pipesEnd: Beveled End,Plain End
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ASTM A312 TP 317L Stainless Steel Seamless PipeName:ASTM A312 TP 317L Stainless Steel Seamless PipeSize:1/2″ – 12″ (DN15–DN300), larger on request Thickness:Schedule 5S - Schedule XXS Standards:ASTM A312 / ASME SA312; EN 1.4438; NACE MR0175/ISO
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Stainless Steel Forged Flange OEM ManufacturerName:ASTM A350 GR. LF2 CL.1 FlangeSize:1/2 ~ 24Sealing Surface Type: RF (Raised Face), RTJ (Ring Joint, suitable for high voltage Class 600+), FF (Flat Face), MFM (Concave-convex Face)Flange
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ASTM A312 TP304 Stainless Steel Seamless PipeASTM A312 TP304 stainless steel seamless pipe manufacturer supplying UNS S30400 pipe in customized sizes, schedules and lengths with inspection, MTC and export packaging.
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Heat Exchanger Tubes ASTM A213 TP304 / TP316LName:Seamless Stainless Steel Heat Exchanger Tubes ASTM A213 TP304 / TP316LSize:1/2 ~ 12Implementation Standards:ASTM A213 — Seamless stainless steel tubes for boilers and heat exchangers (most
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Alloy Steel Butt Weld Elbow ManufacturerAlloy Steel :ASTM A234 / ASME SA234Grade:WP1/ WP5 / WP9 / WP11 / WP22 / WP91 etc.Type:Seamless / Welded /Size:1/4 NB TO 32 NB. (Seamless & Welded)Wall Thickness:Sch. 58 To Sch.
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ASTM A790 UNS S32760 Super Duplex Stainless Steel PipeASTM A790 UNS S32760 super duplex stainless steel pipe: PREN >40, 750 MPa tensile / 550 MPa yield. For offshore, subsea, desalination & sour-service piping.
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316L Stainless Steel PipeName:316L Stainless Steel PipeType: Seamless, WeldedOD: 1/2-48Thickness: SCH5-SCHXXSLength: 0-12M, CustomizedProcess: Hot/Cold Rolled, Hot work, Cold drawnApplication:Chemical Industry And Energy,
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A312 TP347H Stainless Steel Seamless PipeTypical grades:UNS S34709EN 1.4961ASTM 347HASME SA213 TP347H
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ASTM A335 P9 Seamless Alloy Steel PipeMaterial Standard:ASTM A335Grade No.:P9Type:seamless steel pipeEnd:Beveled End,Plain End
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ASTM A790 S32750 Super Duplex PipeWelded Pipe : 5.0 to 1219.2 mm ODSeamless Pipe :6 to 250 mm ODThickness: 0.3 to 50 mm
Why choose us
One-Stop Customized Solutions
We are committed to providing customers with one-stop customized solutions — from design support and precision manufacturing to quality assurance — to meet the diverse needs of various industries for high-performance, high-precision, and high-reliability industrial components.
Certification
We ensure quality through comprehensive system certifications: the company has passed the ISO 9001:2015 quality management system certification and the American Petroleum Institute (API) quality certification system.
Sales Market
Our products have been successfully exported to many countries and regions around the world, including the United States, Canada, Germany, India, Malaysia, Pakistan, the United Arab Emirates, Egypt, and the Middle East. We have earned the trust and praise of overseas customers.
On-Site Quality Supervision
We dispatch professional quality inspection teams to supervise the production of steel pipe fittings and rubber hoses. From raw material entry to the shipment of finished products, we maintain strict quality control throughout the process and accommodate special customer requirements, such as product identification and packaging methods.
Steel Pipe
Steel pipes are long and hollow tubes that are used for many different applications in a variety of places. Its versatility makes pipes the most often used product that is produced by the steel industry. They are commonly used to convey fluid substances that can flow, and small solid particles.
Steel Pipe Specifications
Sizes
Defined by nominal diameter (ND) or nominal pipe size (NPS), ranging from small (1/8 inch) to large (60 inches) diameters. Diameter determines the flow capacity.
Dimensions
Includes outside diameter (OD), inside diameter (ID), and wall thickness.
Weight
Determined by the pipe’s size and wall thickness, usually measured in pounds per foot or kilograms per meter. It helps determine transportation costs and structural load considerations.
Schedules
Indicates the wall thickness relative to the diameter, with common schedules including SCH 40, SCH 80, and SCH 160. Higher schedules mean thicker walls and higher pressure capacity.

Welded Steel Pipe – Manufactured using welding techniques, it has robust structure, high precision, and is more economical than other types. With optimal durability under pressure and extreme conditions, welded pipes are the primary choice in construction, water distribution, and oil & gas industries, where efficiency and reliability are essential.
Seamless Steel Pipe – A pipe made without joints, commonly used in industrial piping systems for oil and gas.
Stainless Steel Pipe – A steel pipe with specific characteristics to enhance resistance to environmental conditions, such as food and pharmaceutical industries.
Alloy Steel Pipe – A steel pipe containing additional elements designed for specific industrial applications.
Automotive Industry
●Exhaust Systems: Steel pipes, often stainless steel due to its corrosion resistance, are extensively used in automotive exhaust systems to channel hot gases away from the engine.
●Chassis and Frames: High-strength steel pipes form the backbone of many vehicle chassis and frames, providing structural integrity and crashworthiness.
●Fluid Lines: Steel pipes transport various fluids within vehicles, including fuel, brake fluid, and coolant.
Machinery and Equipment
●Hydraulic and Pneumatic Systems: Steel pipes are essential for conveying pressurized fluids in hydraulic and pneumatic systems, powering machinery and equipment across industries.
●Pressure Vessels: Seamless steel pipes are often used to construct pressure vessels, which store and contain fluids or gases under pressure.
●Conveyor Systems: Steel pipes can be used as rollers or structural supports in conveyor systems, facilitating the movement of materials in factories and warehouses.


Consumer Goods
●Furniture: Steel pipes are increasingly popular in furniture design, adding a modern industrial aesthetic to chairs, tables, and shelving units.
●Appliances: Steel pipes are found in various household appliances, such as refrigerators (for coolant lines) and washing machines (for water inlet and drainpipes).
Safety and Security
●Handrails and Guardrails: Steel pipes provide safety and support as handrails along staircases and walkways, and as guardrails to prevent falls from elevated platforms or balconies.
●Bollards: Security bollards, often made from steel pipes, are strategically placed to control vehicle access and protect pedestrians and property.
●Bike Racks: Steel’s durability and resistance to bending make it a preferred material for bike racks, providing secure storage for bicycles.
Nominal pipe size & outside diameter size chart
For example, below is a table of NPS values from ½” to 3 ½” with their corresponding outside diameter:
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Nominal Pipe Size (NPS) |
Outside Diameter (OD) |
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½” |
0.84” |
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¾” |
1.05” |
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1” |
1.315” |
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1 ¼” |
1.66” |
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1 ½” |
1.9” |
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2” |
2.375” |
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2 ½” |
2.875” |
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3” |
3.5” |
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3 ½” |
4” |
How is Steel Pipe Made?
The manufacturing process of steel pipes involves several steps, each crucial for ensuring the pipe’s strength, durability, and compliance with industry standards:
Raw Material Selection: High-quality steel is chosen based on the intended use of the pipe.Melting and Casting: Steel is melted in a furnace and cast into billets or slabs.
Forming: The billets or slabs are then heated and rolled into a cylindrical shape.
Electric Resistance Welding (ERW): This is the most common method. Coiled steel sheets are formed into a cylindrical shape and their edges are heated with high-frequency electric current. The molten metal fuses together, creating a strong weld.
Seamless Pipe Manufacturing: For seamless pipes, the billet is pierced to create a hollow tube, then rolled and stretched to the desired size. This method produces pipes with superior strength and is often used for high-pressure applications.
Sizing and Shaping: Pipes are sized and shaped according to specifications through a series of rollers.
Heat Treatment: Pipes undergo heat treatment to improve their mechanical properties.
Inspection and Testing: Pipes are inspected for defects and tested for strength, durability, and compliance with standards.
Our Certificate




FAQ
As one of the leading steel pipe manufacturers and suppliers in China, we warmly welcome you to buy high quality steel pipe for sale here from our factory. Good service and reasonable price are available.

