Seamless steel pipes are manufactured from solid round steel billets that are perforated to create a hollow tube with no welds on the surface, hence the name "seamless steel pipes."
Types of Seamless Steel Pipes by Production Method:
Seamless steel pipes can be categorized based on their production process into:
Hot-rolled seamless steel pipes
Cold-rolled seamless steel pipes
Cold-drawn seamless steel pipes
Extruded seamless steel pipes
Pipe jacking, among others.
Types of Seamless Steel Pipes by Section Shape:
Seamless steel pipes are classified by their cross-sectional shape into round and shaped pipes. Shaped pipes include a variety of forms such as square, oval, triangular, hexagonal, melon seed, star, finned tube, and other complex shapes. The diameter of these pipes can range from a minimum of 4mm to a maximum of 900mm.
Types of Seamless Steel Pipes by Wall Thickness:
Depending on the application, seamless steel pipes are divided into thick-walled and thin-walled types.
Applications of Seamless Steel Pipes:
Seamless steel pipes are widely used in various industries, including:
Petroleum geological drilling pipes
Petrochemical cracking pipes
Boiler furnace pipes
Bearing pipes
High-precision structural steel pipes for automobiles, tractors, and aviation.
Implementation Standards for Seamless Steel Pipes:
Universal Seamless Steel Pipe (ASTM A53 GR.B):
Steel Grade: SA53 B
Specifications: 1/4" to 28" (13.7mm to 711.2mm)
Tensile Strength: ≥ 415 MPa
Yield Strength: ≥ 240 MPa
Standard: ASTM A53 for pressure piping systems, general purpose piping, and piping used at temperatures below 350°C.
Seamless Steel Piping for High-Temperature Operation (ASTM A106 GR.B):
Steel Grade: SA106B
Specifications: 1/4" to 28" (13.7mm to 711.2mm)
Standard: ASTM A106 by the American Society for Testing and Materials (ASTM)
Mechanical Properties:
Tensile Strength: ≥ 415 MPa
Yield Strength: ≥ 240 MPa
Chemical Composition:
Carbon (C): ≤ 0.30%
Silicon (Si): ≥ 0.10%
Manganese (Mn): 0.29–1.06%
Phosphorus (P): ≤ 0.035%
Sulfur (S): ≤ 0.035%
Chromium (Cr): ≤ 0.40%
Molybdenum (Mo): ≤ 0.15%
Copper (Cu): ≤ 0.40%
Nickel (Ni): ≤ 0.40%
Vanadium (V): ≤ 0.08%
Line Pipe (API SPEC 5L):
Steel Grades: B, X42, X46, X52
Specifications: 1/4" to 28" (13.7mm to 711.2mm)
Additional Standards for Seamless Steel Pipes:
ASTM A53: Seamless and welded black steel pipes and hot-dip galvanized steel pipes.
ASTM A106: Carbon steel seamless pipes for high-temperature operation.
ASTM A178/A178M: Resistance welded carbon steel and carbon-manganese steel boiler tubes.
ASTM A179/A179M: Seamless cold-drawn low-carbon steel heat exchanger and condenser tubes.
ASTM A192/A192M: Carbon steel seamless boiler tubes for high-pressure service.
ASTM A199/A199M: Medium alloy steel cold-drawn seamless tubes for heat exchangers and condensers.
ASTM A209/A209M: Carbon steel seamless tubes for boilers and superheaters under high pressure.
ASTM A210/210M: Medium-carbon steel seamless tubes for boilers and superheaters.
ASTM A333/A333M: Seamless and welded steel pipes for low-temperature service.
ASTM A500/A500M: Cold-formed welded and seamless carbon steel structural tubes for round and shaped sections.