HSLA Column Pipe

Built from high-strength, corrosion-resistant HSLA steel, this column is NSF 61 certified, AIS compliant, and eliminates the need for epoxy coating. Proven through field and lab testing for superior performance.

HSLA STEEL

  • Steel adhering to ASTM A606 Type 4 is commonly referred to as High-Strength, Low-Alloy (HSLA)

  • Developed by U.S. Steel mills in the 1940’s for use in the Water Well industry

  • Minimum Yield Strength of 50,000 psi compared to 35,000 psi for Mild Steel
  • 9x more corrosion resistant than Mild Steel based on

Key Advantages

  • Higher Strength & Corrosion Resistance

  • NSF 61 Certified

  • AIS Domestic
  • Eliminates Need for Epoxy Coating

Straight Butt Thread

Pipe Diameter Wall Thickness TPI A Minor Diameter B
6.625 0.250
0.312		 8 6.700 6.454–6.440
8.625 0.312
0.375		 8 8.700 8.454–8.440
10.750 0.312
0.375		 8 10.812 10.580–10.566
12.750 0.375 8 12.812 12.554–12.542
Coupling OD L P.D. T
7.312 4.125 6.527–6.517 0.250
9.625 4.624 8.529–8.517 0.250
11.750 6.125 10.652–10.642 0.250
13.937 6.125 12.652–12.642 0.250

Values listed in inches. Additional Wall Thicknesses available.

Tapered Thread (NPT)

0.9586.505

Pipe Diameter Wall Thickness Length L₁ Diameter E₁
6.625 0.250
0.312
8.625 0.312
0.375		 1.063 8.500
10.750 0.312
0.375		 1.210 10.620
12.750 0.375 1.360 12.617
Effective Thread Diameter E₂ Wrench Make Up Thread Overall Length L₂
6.540 1.188 1.946
8.540 1.312 2.146
10.665 1.500 2.358
12.665 1.630 2.558
NPS Load Capacity (lbs)
6 80,000
8 140,000
10 160,000
12 160,000

Load values calculated for Straight Butt-Threaded, Oil Lubed joints. For NPT and Water-Lubed joints, load values could be slightly less.

Independently NSF Certified®
Independently NSF Certified®

The Evolution of Pipe: Not Your Grandfather’s Pipe

Typical % Composition By Weight

Strength in PSI

Time Period Steel Type CU CR NI SI P G101 Corrosion Index Yield Tensile
1900 – 1940 Hard Red 0.20 0.00 0.00 0.00 0.01 4.11 55,000 70,000
1940 – 1980 COR-TEN 0.41 0.84 0.28 0.48 0.09 8.35 50,000 70,000
1940 – 1980 Kai-Well 0.27 0.00 0.09 0.09 0.04 5.36 55,000 70,000
1940 – 1980 USS Well Casing 0.26 0.00 0.00 0.08 0.03 5.06 50,000 70,000
1980 – Present HSLA ASTM A606 Type 4 0.31 0.72 0.26 0.29 0.02 6.87 55,000 75,000
1980 – Present Copper Bearing 0.20 0.02 0.01 0.00 0.03 3.91 44,000 68,000
1980 – Present Mild Steel 0.00 0.00 0.00 0.00 0.00 0.00 35,000 50,000

Understanding the Protective Coating of ASTM A606 Type 4 Steel

ASTM A606 Type 4, also known as weathering steel or COR-TEN®, is a high-strength, low-alloy (HSLA) steel that develops a natural, protective rust layer over time. This self-sealing oxide layer eliminates the need for painting or other corrosion prevention methods, making it ideal for exposed structural and architectural applications.

We’ve published a technical memo detailing the electrochemical process behind the formation of this protective coating, including the role of alloying elements like copper, chromium, and phosphorus.