Schedule 40 Galvanized Pipe
We supply sch 40 galvanized steel pipe, also ordered as GI pipe Sch 40. It is made to ASTM A53 Grade B with ASME B36.10 walls and hot-dip galvanized. Sizes run from 1/2" to 12".
Threaded and coupled with NPT threads, or plain end for grooving
Sch 80 and Sch 10 in the same sizes, for higher or lower pressure
21 ft and 6 m lengths, or cut to your size
Every length stenciled with size, Schedule, grade and heat number
Why Order Schedule 40 Galvanized Steel Pipe From Us
01
Walls to ASME B36.10, Not "Close Enough"
We check wall on every lot against B36.10 minimums. You get the true Sch 40 wall, not a lighter "Sch 40 type".
02
ASTM A53 Grade B Steel
Type E (ERW) or Type S (seamless), Grade B. Mill certificates to EN 10204 3.1.
03
Clean NPT Threads
Threads are cut to ASME B1.20.1 after galvanizing and gauged per lot. Each length ships with a coupling and thread protector.
04
Hot-Dip Coat Inside and Out
Zinc meets the A53 coating minimum, tested per lot. The bore is protected for water and sprinkler service.
05
8–12 Working Days Lead Time
Typical lead time is 8–12 working days. We keep 9,000 tons of galvanized pipe & tube in stock (out of 80,000 tons in total). Sch 80 and larger sizes take 3-4 weeks.
Schedule 40 Galvanized Pipe, the Standard Wall for US Projects
Schedule 40 is the most used pipe wall in the Americas. It is thick enough to thread, strong enough for water and fire lines, and light enough to install by hand. Many specs simply write “galvanized Schedule 40” and expect A53 Grade B.
Galvanized schedule 40 pipe fits standard malleable fittings, grooved couplings and flanges. That makes it easy to source fittings anywhere. If your drawing does not name a wall, Sch 40 is usually what the engineer means.
Schedule 40 and Other Wall Classes
Schedule 40 Galvanized Steel Pipe
The standard wall, also called STD up to 10". Threaded or plain end, 1/2" to 12".
Schedule 80 Galvanized Pipe
Heavy wall for higher pressure and deep threads. Often written XS or Sch 80.
Schedule 10 Galvanized Pipe
Light wall for sprinkler mains, grooved or plain end. Supplied to ASTM A795 or A135.
Threaded Galvanized Pipe
Galvanized pipe with threaded end and coupling, NPT or BSP. Also cut and threaded in short lengths.
Non Threaded Galvanized Pipe
Plain end, unthreaded galvanized pipe for grooved couplings, welding or fence posts.
Specifications
| Item | Range |
|---|---|
| Size | 1/2″ – 12″ (DN15 – DN300) |
| Wall | Sch 10, Sch 40 (STD), Sch 80 (XS) to ASME B36.10 |
| Steel | ASTM A53 Type E / Type S, Grade B; A795 for Sch 10 |
| Coating | Hot-dip to ASTM A53 / A123, 420 g/m² minimum |
| Ends | Threaded and coupled (NPT), BSP on request, plain, grooved |
| Length | 21 ft, 6 m, 5.8 m, 12 m or as requested |
Choosing the Right Wall: Sch 10, Sch 40 or Sch 80
The Schedule number sets the wall. The OD stays the same for every Schedule, so the fittings fit. What changes is pressure rating, weight and price. Here is how to choose.
Schedule 40: The Default
Choose Sch 40 for water service, sprinkler branch lines, handrails and general structures. It takes a full NPT thread with metal to spare. A 2 inch schedule 40 galvanized pipe, for example, has a 3.91 mm wall on a 60.3 mm OD.
Sizes such as 1-5/8″ and 1-7/8″ often appear with Sch 40 on fence lists. Those are OD fence sizes. A 2-3/8″ Sch 40 post is the same as 2″ NPS pipe. See the round pipe page for fence sizes.
Schedule 80: Heavy and Thick Wall
Sch 80 galvanized pipe has a wall about 40% thicker than Sch 40. Choose it for higher pressure, deep threads or heavy duty work. Examples are pump discharge, columns and abrasive service. A 3 inch Sch 80 pipe has a 7.62 mm wall, against 5.49 mm in Sch 40.
Some lists ask for “heavy galvanized pipe” or “thick wall galvanized pipe” without a Schedule. Tell us the pressure or the wall you need. We will match Sch 80, Sch 160 or BS 1387 Heavy.
Schedule 10 and Schedule 20: Lighter Walls
Sch 10 is a light wall for fire sprinkler mains. It is roll-grooved, not threaded, because the wall is too thin. In the US it is made to ASTM A795 or A135.
Schedule 20 in ASME B36.10 starts at 8″. When fence lists ask for 2-3/8″ Schedule 20, they mean a lighter fence post class. We confirm the wall in mm before quoting.
Threaded or Plain End
Threaded galvanised pipe comes threaded and coupled (T&C). Both ends carry NPT threads, with a coupling on one end. A 20mm threaded galvanised pipe in BSP thread is common for BS markets. NPT and BSP threads do not seal together, so name the thread type.
Order plain end for grooved couplings, welding or fence posts. Plain end pipe is slightly cheaper and easier to handle.
Steel Grade
ASTM A53 Grade B is the default for galvanized Sch 40 in North America. Its minimum yield is 240 MPa. Grade A is softer and easier to bend, but rarely asked for today.
Frequently Asked Questions
What is the wall thickness of 2 inch schedule 40 galvanized pipe?
2 inch Sch 40 pipe has a 3.91 mm (0.154") wall on a 60.3 mm OD. The zinc coat adds a little, but the wall is measured on the steel. Sch 80 in the same size has a 5.54 mm wall.
Is GI pipe Sch 40 the same as ASTM A53 Schedule 40 galvanized steel pipe?
Usually, yes. "GI pipe Sch 40" names the wall and the coating. The steel and test standard is often ASTM A53 Grade B. If your spec names a different standard, tell us so we certify to it.
Is Sch 40 the same as STD?
Yes, from 1/8" to 10". Above 10", STD stays at a 9.53 mm wall while Sch 40 gets thicker. Sch 80 equals XS up to 8".
Can I buy schedule 40 galvanized pipe by the piece size, like 1-1/2" or 4"?
Yes. We supply every common size from 1/2" to 12", including 1", 1-1/4", 1-1/2", 2-1/2", 3", 4" and 6". Order in full lengths or cut lengths. Minimum order depends on size.
How much does schedule 40 galvanized pipe cost?
Price depends on size, wall, ends and quantity. Steel and zinc move it week to week. Send your list, and we will quote within 8 working hours.
Request a Quote
We reply within 2–4 working hours with a price per ton, valid for 3 days.