What are CSA 350 W Pipes?

This specification refers to Hollow Structural Sections (HSS) under the Canadian steel grading system. The manufacturing for these piping is typically limited to EWR or electric resistance welding, sometimes without using a bead. 

CSA 350W pipes may be available in many shapes: square, round, and rectangular. They may also include cold-rolled or hot-formed steel. Among all grades under this specification, Class C is the most commonly recognized. This hollow steel structural section is primarily used in bridges and construction projects.

Builders may opt for CSA 250 W pipes over conventionally used ASTM A500 products because of their enhanced yield strength. In addition, these pipes also have lower thickness tolerance than ASTM piping, ranging from +10% to -5%. For mass tolerance, CSA 350 W pipes also bear up to +10% to -3.5% in theoretical weight.

These are high-strength, low-alloy piping used in structures such as steel columns and trusses.

Characteristic Features of 350 W Pipes

  • Outside Diameter of round tubes of CSA 350 W is 0.840 inches to 20 inches.
  • Depending on the tube sizing, the general thickness for these pipes varies from 0.100 inches to 0.750 inches
  • The metric equivalent of CSA 350 W pipe is 350 MPa.
  • The yield strength of these pipes is 50000 PSI
  • The tensile strength for CSA 350 pipes varies from 65000 PSI to 90000 PSI.
  • These pipes also have lower thickness tolerance than ASTM piping, ranging from +10% to -5%. 
  • For mass tolerance, CSA 350 W pipes also bear up to +10% to -3.5% in theoretical weight.

Equivalent Grades for CSA 350 Pipes

 Place  Grade
USAA572 A678 Gr. A SS Grade 50
JapanSM490A SS490
ChinaQ345B Q345C
InterE355C Fe510B

Tensile Properties of CSA 350 W Pipes

 Mechanical Properties  Value
 Tensile Strength 65 to 95 ksi
 Yield Strength 50 ksi (min)
 Elongation 19% min in 8 inches to 22% min in 2 inches

Chemical Properties of CSA 350 W Pipes

 Chemical Component Percentage Present  (Max)
Sulfur 0.04%

What Are ASTM A500 Pipes?

ASTM A500 pipes are those with tensile strength and corrosion resistance appropriate enough to work as a high-grade structural framework for construction projects. These pipes are available in numerous sizes, covering both seamless and cold-finished piping. A500 pipes are versatile and have several uses in construction owing to their shaped availability. This piping can be found in various shoes, helping fit the requirements of different building projects.

Characteristic Features of ASTM A500 Pipes

  • Alongside round, rectangular, and square tubing, ASTM A500 also covers welded, bolted, and riveted tubing shapes for use in construction.
  • An adjacent specification/counterpart to ASTM A500 is ASME SA500.
  • In comparison to ASTM A53 pipes, A500 piping has straightness tolerances of ¼” per every 10 feet, leading to better application in projects requiring curved structural steel. 
  • The Outer Diameter(OD) of A500 pipes ranges from 0.4 to 32.2 inches.
  • The length of ASTM A500 pipes is usually limited to 18 feet.
  • The wall thickness of these pipes varies from 0.8 mm to 75 mm.
  • This specification states that A500 welded pipes must be made from electric resistance welding for optimum strength. The steel used must be flat-rolled, and the end result must be unfurnished, still containing the flash. 
  • Grade B of ASTM A500 pipe have higher strength and closer tolerances fit for application in construction.
  • Longitudinal welding is preferred in welded pipes, especially one that uses butt joints that can be fused longitudinally to ensure the structural strength and design of the construction pipe.
  • ASTM A500 carbon steel pipes are to be made using open earth, electric, or basic oxygen furnaces. 
  • Dimensional variations on wall thickness, Outside Diameter (OD), twist, and structural straightness are available during A500 pipe production. 

Reference Specifications for ASTM A500 PIpes

  • ASTM A752: This specification provides the testing practices and methods, as well as the terminology/definitions for chemically testing ASTM A500 steel pipes.
  • ASTM 700: The post-product steps of ASTM A500 pipes are guided by the standards set by this specification. ASTM 700 sets up practices for pipe marking, packaging, and loading for shipments.
  • ASTM A941: This standard provides the definitions of A500 pipes, including stainless steel, iron-based alloys, and other related alloy pipes.
  • ASTM 370: Mechanical testing is necessary to check the flaws in the piping products. ASTM 7– provides the setup, including terminology and methods for successfully testing defects in ASTM A500 pipes.

Chemical Composition of ASTM A500 Pipes

  Element   ASTM A500 Grade A, Grade B, Grade D           ASTM A500 Grade C
   Heat Analysis  Product Analysis  Heat Analysis  Product Analysis
  Carbon  0.26% (max)  0.30% (max)  0.23% (max)  0.27% (max)
  Manganese  1.35% (max)  1.40% (max)  1.35% (max)  1.40% (max)
  Phosphorous  0.035% (max)  0.035% (max)  0.035% (max)  0.045% (max)
  Sulfur  0.035% (max)  0.045% (max)  0.035% (max)  0.045% (max)
  Copper  0.20% (min)  0.18% (min)  0.20% (min)  0.18% (min)

Tensile Properties of ASTM A500 Pipes (Shaped Structural Tubing)

                                           Shaped Structural Tubing
   Grade D  Grade C  Grade B  Grade A
  Elongation %(In 2 inches)  23% (min)  21% (min)  23% (min)    25% (min)
  Yield Strength  250 MPa (min)  345 MPa (min)  315 MPa (min)  270 MPa (min)
  Tensile Strength  400 MPa (min)  425 MPa (min)  400 MPa (min)  310 MPa (min)


Tensile Properties of ASTM A500 Pipes (Round Structural Tubing)

                                           Round Structural Tubing
   Grade D  Grade C  Grade B  Grade A
  Elongation %(In 2 inches)  23% (min)  21% (min)  23% (min)    25% (min)
  Yield Strength  250 MPa (min)  315 MPa (min)  290MPa (min)  230 MPa (min)
  Tensile Strength  400 MPa (min)  425 MPa (min)  400 MPa (min)  310 MPa (min)

Differences Between CSA 350W and ASTM A500 Pipes

 ASTM A500 Pipes CSA 350W Pipes
The Wall Thickness Tolerance for these pipes is +/-10%. CSA 350W pipes have a WT Tolerance of +10% to -3.5%.
The Tensile Strength for these pipes is around 62,000 psi.350 W pipes have a Yield Strength ranging from 65,000 to 90,000 psi.
ASTM A500 pipes are typically used in construction. The bolting, welding, and riveting material used in the construction of bridges and buildings involve steel under this specification.These pipes are based on specifications for steel used as plates, shapes, sheet piling, hollow sections, bars, and more.
ASTM A500 covers specs for cold-formed pipes and seamless/welded pipes. It includes carbon steel structural tubing, typically available in shapes and rounds. This specification covers standards for rolled/welded hollow sections and structural quality steel.