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Mild Steel Weld Els and Pipe for Turbo Manifold Fabrication

Mild Steel Weld Els and Pipe for Turbo Manifold Fabrication

UPDATE 10/28/2022: We have discontinued our line of Mild Steel Weld Els and will no longer be offering them. The remaining in stock items are on clearance and are being offered at a discount. We strongly recommend using 304 Stainless Weld Els for turbo manifold fabrication.


Mild Steel Pipe and Pipe Fittings (often referred to as "Weld Els") are an affordable solution for manufacturers and fabricators who are fabricating turbo manifolds. Mild steel, or carbon steel, pipe and weld els are on average about 35% cheaper than their 304 Stainless Steel counterparts, handle the thermal expansion of a turbo manifold well, and can be welded up with a simple MIG welder with ease. For fabricators who are looking to ceramic coat their turbo manifold, mild steel pipe and fittings are an economical choice with long-lasting durability.  


We've cover the differences between pipe and tube size material in regard to fabricating a turbo manifold in an earlier blog post, which can be found here, and we always like to reiterate the major difference between pipe and tube size material as it can always be a bit confusing. 

Pipe size, or Nominal Pipe Size (NPS), is a North American industry designation, or "trade size", that was standardized by the American Standards Association. The use of the word "nominal" in the NPS designation refers to non-specific terms and identifies the diameter of the hole with a non-dimensional number. For example, one of the most common pipe sizes to use when fabrication a turbo manifold out of Mild Steel material is 1-1/2" Schedule 40; however, the approximate outside diameter (OD) of this material is 1.900" and the approximate inside diameter (ID) is 1.610". Based on those dimensions it's easy to see that even though the material is referred to as 1-1/2" pipe there isn't a single dimension that is actually 1.500". Due to the nominal sizing of pipe we never list or reference the material on our website as a decimal (e.g., 1.500") like we do with tube size material. 

The confusion about pipe size measurements doesn't stop with the mismatch between the named size and the actual size — the wall thickness can also vary in relation to the nominal pipe size. Unlike the wall thickness of tube size material, which is referenced by a gauge that remains constant regardless of the outside diameter, pipe size material refers to the wall thickness as a "schedule" and the thickness will vary depending on the nominal pipe size itself.  As you can see from the table below, the wall thickness of 1-1/2" Schedule 40 pipe is 0.145", whereas, the wall thickness of 2-1/2" Schedule 40 is 0.154". When referencing pipe sizes from 1/8" to 4", the actual thickness of Schedule 40 material can range between 0.068" and 0.237", as compared to tube size material where 16 gauge is 0.065"[*] regardless of the outside diameter. 

It's is important to note that pipe size material (weld els, tees, reducers, straight lengths of pipe, etc.) is not compatible with tube size material (mandrel bends, tube fittings, straight lengths of tubing, etc.). Always be sure to verify that the selected type and size of material meets the requirements of your project and is compatible with the other components used in your project. Please contact us at anytime if you have any questions or need technical assistance when selecting material types and sizes.

[*] 16 gauge is typically referenced as 0.065" in both the automotive and industrial industries. However, ASTM A269 tolerances state that there can be up to a 10% variation from the stated wall thickness For example, material ranging from 0.500" to 5.500" outside diameter. For material in this size range 16 gauge material can technically range from 0.0585" at a minimum to 0.0715" at a maximum. However, most stainless tube manufacturers tend to produce 16 gauge tube with a wall thickness that ranges between 0.059" and 0.065" thick. More information about ASTM A269 can be found here.
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Ace Race Parts - October 17, 2022

Hi Rando,

Thank you for the comment. We discontinued our line of Mild Steel fittings and are selling off the remaining fittings a large discount. Once the remaining items are gone we will remove the mild steel fittings from our catalog/site.

Thank you!

Rando - October 17, 2022

Hello, im looking for 90 degree bends for manifold and i cant find them
i found T-fittings mild steel but cant find 90 degree fittings

Ace Race Parts - January 22, 2021

Hi Gaëtan,

Thank you for the message! We’re more than happy to help find the cheapest method of shipping to your location. Please contact us and we’ll send over a couple of quotes as soon as possible.

Thank you,
Ace Race Parts

Gaëtan Montavon - January 22, 2021

Hello, I loooking for bends for a manifold.
The problem is that im from switzerland and the shipping costs are twice the price of my order. Is there a possibility to have a cheaper shipping option ?
thank you very much for your answer.

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