Pipes and tubes are often used interchangeably, but they have distinct characteristics, applications, and standards depending on the industry. Here's an overview of their differences and uses
Pipes Generally refer to a cylindrical conduit that conveys substances such as liquids, gases, or solids (in slurries). They are defined by their internal diameter (ID) and are primarily measured by "nominal pipe size" (NPS) and "schedule" (for wall thickness).
Tubes can be cylindrical, but they may also have other cross-sections (e.g., square, rectangular). They are defined by their external diameter (OD) and thickness and are used for structural purposes as well as transporting fluids.
Pipes Measurment: Measured by nominal diameter and wall thickness, often referred to by schedule numbers (e.g., Schedule 40 or Schedule 80). Example: A 2" nominal pipe doesn’t necessarily have an outer diameter of 2 inches—it’s a standard size.
Tubes Measurment: Measured by their outer diameter (OD) and wall thickness, typically with more precise measurements than pipes. Example: A 2" tube has exactly a 2-inch outer diameter.
Specifications for Pipes & Tubes
Dimensions |
ASTM, ASME and API |
Size: |
1/4"Nb to 28"Nb (Seamless)
1/4"Nb to 48"Nb (Welded) |
Schedule: |
SCH5, SCH5S, SCH10, SCH10S, SCH20, SCH30, SCH40, STD, SCH80, XS, SCH60, SCH80, SCH120, SCH140, SCH160, XXS |
Type: |
Seamless / ERW / EFW / Welded / Fabricated / LSAW Pipes |
Form: |
Seamless Pipes, ERW Pipe, EFW, Pipe, H-SAW Pipe, L-SAW Pipe, Seamless Tube, ERW Tube, Square Pipe, Rectangular Pipe. |
Length: |
Single Random, Double Random & Custom Cut Length |
End: |
Plain End, Beveled End, Treaded |
Stainless Steel Pipes & Tubes
Standards: |
ASTM A312 / A213 / A269 / A358 / A778 |
Grades: |
TP 201, 202, 301, 302, 304, 304L, 309, 310, 316, 316L, 316LN, 316Ti, 317L, 321, 347, 405, 409, 410, 420, 430, 440C, 904L, AL-6XN (N08367). |
Carbon Steel Pipes & Tubes
Standards: |
ASTM A106 / A53 / A179 / A333 / A210 |
Grades: |
Gr. B, API 5L X42/X46/X52/X56/X60/X65/X70 PSL-1 / PSL-2, Gr, 3, 6, IS 1239, IS 3589, Boiler Tube – BS 3059 – Gr. 320, 360, Gr. A1, BS 6323, T2, T11, T12, T22, T91, T92 . |
Alloy Steel Pipes & Tubes
Standards: |
ASTM A335 / A213 |
Grades: |
P11, P12, P22, P5, P9, P91, T11, T12, T22, T5, T9, T91. |
Duplex & Super Duplex Steel Pipes & Tubes
Standards: |
ASTM A789, A790, A928 |
Grades: |
2205 (S31803 / S32205), SMO254 (S32154), 2507 (S32750 / S32760), Ferralium 255 (S32550), SMO 654 (S32654). |
Nickel Alloy Pipes & Tubes
Standards: |
ASTM B 161 ASME SB 161 / ASTM B729 ASME SB729 |
Grades: |
200 (N02200), 201 (N02201), Alloy 20 (N08020). |
Monel Alloy Pipes & Tubes
Standards: |
ASTM B165 ASME SB165 / ASTM B725 ASME SB725 |
Grades: |
400 (N04400), 500 (N05500). |
Inconel Pipes & Tubes
Standards: |
ASTM B167,B444, B407, B423, B677 |
Grades: |
600 (N06600), 601 (N06601), 625 (N06625), 718 (N07718), 800 (N08800), 800H (N08810), 800HT (N08811),– 825 (N08825), 904L (N08904). |
Copper Alloy Pipes & Tubes
Standards: |
ASTM B111 ASME SB111 / ASTM B466 ASME SB466 |
Grades: |
Commercial, ETP, OFE, CuNi 90/10 (C70600), CuNi 70/30 (C71500), Brass, Naval Brass, Aluminium Bronze, Admiralty Brass. |
Hastelloy Pipes & Tubes
Standards: |
ASTM B622 ASME SB622 / ASTM B619 ASME SB619 |
Grades: |
C726 (N10276), C4 (N06455), C22 (N06022), C2000 (N06200), X (N06002), B2 (N10665), B3 (N10675). |
Monel Pipes & Tubes
Standards: |
ASTM B165 ASME SB165 / ASTM B725 ASME SB725 |
Grades: |
400 (N04400), 500 (N05500). |
Titanium Pipes & Tubes
Standards: |
ASTM B338 / B861 / B862 |
Grades: |
2, 5 (Ti6AI4V), 7. |
Cupro Nickel Pipes & Tubes
Standards: |
ASTM B 466 ASME SB 466 / ASTM B 467 ASME SB 467 |
Grades: |
Cupro Nickel 90 / 10 & Cupro Nickel 70/30 |
Copper Pipes & Tubes
Standards: |
ASTM B 280 ASME SB 280 / ASTM B 68 ASME SB 68 |
Grades: |
C12200 |
Mild Steel Pipes & Tubes
Grades: |
IS – 1239 (Part -1) 2004, Equivalent to BS – 1387 / 1985 |