Stainless Steel Tube Fittings
Profab Machine makes stainless steel tube fittings in 304 and 316L by CNC machining, including tube adapters, tube-to-thread adapters, hose barb fittings, and sanitary clamp ferrules. We make them to your drawing or sample, from a prototype run to a production order.
What Are Stainless Steel Tube Fittings?
Stainless steel tube fittings are the parts that join a tube to another tube, a thread, a hose, or a clamp. A tube fitting is sized by the tube's outside diameter and wall, unlike a pipe fitting. For that reason the fitting must match the tube before it matches the port.
Profab Machine turns and mills stainless steel tube fittings from 304 or 316L bar to your drawing or sample. That includes weld-in tube adapters, tube-to-thread adapters, hose barb fittings, and sanitary clamp ferrules. We offer polishing, electropolishing, and passivation when a clean surface is needed. We can also match a finish from matte to bright polish to your request.
Choosing the Right Grade
304 Stainless
304 is the usual grade for stainless steel tube fittings on indoor machinery, automation, and washdown lines without chlorides. 304 machines cleanly and keeps the price down on larger orders. However, 304 is not the right choice for salt spray or chloride-heavy process water.
316 / 316L Stainless
316L is the grade for stainless steel tube fittings that meet salt, chlorides, or cleaning chemicals. Its 2 to 3% molybdenum improves resistance to pitting compared with 304.
Other Grades
Duplex 2205 and other stainless grades are available on request when the media or the temperature calls for them.
Polishing, electropolishing, and passivation are available when a cleaner surface is needed.
Diverse Applications of Stainless Steel Tube Fittings
Stainless steel tube fittings sit where tubing meets a port, a hose, a clamp, or a rod end. Stainless steel is chosen for those joints where steel would rust or where cleaning chemicals are used. Profab Machine makes them to your drawing or sample, from a prototype run to a production order.
Ferrules for Pharmaceutical Piping
Stainless steel sanitary clamp ferrules join tubing to the ports of bioreactors and CIP skids. 316L is chosen because it handles frequent cleaning chemistry.
Hose Barbs for Beverage Filling Lines
A stainless steel hose barb fitting joins flexible hose to a tube or tank port at filler and transfer pump stations. 304 or 316L cleans down without rust.
Thread Adapters for Chemical Skids
Stainless steel tube-to-thread adapters connect sample and instrument tubing to NPT or BSP ports on chemical skids. 316L resists the chlorides in process media.
Tube Adapters for Off-Road Linkages
Weld-in stainless steel tube adapters carry a rod end at the end of a control arm, tie rod, or sway bar link tube. Stainless steel keeps the thread clean in mud and salt.
How to Specify Stainless Steel Tube Fittings
Work through these points before you request a quote.
| Factor | What to Confirm | Why It Matters |
|---|---|---|
| Tube | Outside diameter, wall thickness, material, inch or metric | The fitting must match the tube before it matches the port. |
| End at each side | Weld-in, internal thread, external thread, hose barb, sanitary clamp, or ferrule | Each end is chosen on its own, so one fitting can carry two different ends. |
| Thread | Standard, size, pitch, and right or left hand | NPT, BSP, and metric threads do not mate with each other. |
| Seal | Taper thread, bonded washer, O-ring, or gasket face | The thread alone does not seal a parallel thread. |
| Grade | 304, 316L, or another grade on request | The media and the chloride level set the grade. |
| Surface | As machined, polished, electropolished, or passivated | A clean surface may need a finish step. |
| Quantity and drawing | Prototype or production run, and DXF, DWG, STEP, IGES, or PDF | A drawing or a sample with the dimensions lets us quote. |
Thread and End Reference
These are the common thread standards on stainless steel tube fittings. Confirm the standard on every drawing.
| Standard | Thread Form | How It Seals | Note |
|---|---|---|---|
| NPT | 60 degree, tapered 1:16, ASME B1.20.1 | On the thread, with sealant | NPT is common in North America. |
| BSPT | 55 degree, tapered 1:16, ISO 7-1 | On the thread, with sealant | BSPT does not mate with NPT. |
| BSPP | 55 degree, parallel, ISO 228-1 | On a washer, O-ring, or gasket face | The seal sits outside the thread. |
| Metric and UNF straight | Per your drawing | Per your drawing | Tube adapters for rod ends often use it, for example 3/8-24 in right or left hand. |
| Sanitary clamp | ISO 2852 or DIN 32676 dimensions on request | On a gasket between two ferrules | Name the standard on the drawing. |
Tube Fittings Machined to Your Drawing
Turned to Your Thread and Tube Size
We CNC turn and tap adapters, ferrules, and hose barbs from 304 or 316L bar. That way the thread, the tube outside diameter, and the wall match your drawing.
Both Ends Reviewed Together
Send the tube size, the thread standard, and the end at each side. With those details we check both ends before we quote. That way the NPT, BSP, and metric threads on your drawing match each other.
Samples Before the Run
A sample of your stainless steel tube fitting takes about 20 days, compared with about 30 days for standard production. Tiered pricing is available on larger orders.
Build a Complete System
A stainless steel tube fitting is one piece of a linkage or a line, so these pages cover the products that go with it.
Stainless Steel Rod Ends
The rod end threads into the tube adapter and carries the load. The thread is therefore the first choice.
Learn More
Stainless Steel Clevis
A clevis fits on an adapter with an external thread, which gives a pinned joint.
Learn More
Stainless Steel Tie Rod Ends
A tube with an adapter at each end and a rod end forms a tie rod end.
Learn More
Common Questions
Not seeing your question? Email us at [email protected] and we typically reply same day.
What is the difference between stainless steel tube fittings and pipe fittings?
A tube fitting joins tubing, which is sized by outside diameter and wall thickness. A pipe fitting, by contrast, joins pipe, which is sized by nominal pipe size. A tube fitting also holds the tube with a weld, a clamp face, or a ferrule. A pipe fitting, however, relies on a pipe thread or a weld.
Can you make stainless steel compression tube fittings with ferrules?
We machine fitting bodies, nuts, and ferrules to your drawing or sample. Ferrule systems from different makers are not interchangeable. Send the part or the series name before we quote.
Which thread standards can you cut on stainless steel tube fittings?
We cut NPT, BSPT, BSPP, metric, and UNF threads to your drawing. These threads do not mate with each other. Confirm the standard, the size, and the pitch on every drawing.
What pressure are your stainless steel tube fittings rated for?
We do not publish one pressure rating. That is because the pressure a connection holds depends on the tube wall, the material, the thread, the temperature, and the fitting system. If you send those details with your drawing, we will review the application with you.
Should I choose 304 or 316L for my stainless steel tube fittings?
Choose 304 for indoor machinery and washdown without chlorides. Choose 316L instead where salt, chlorides, or cleaning chemicals are present.
From Inquiry to Delivery
Send Specs
Send a drawing or a sample with the tube outside diameter, wall, thread, and grade.
Respond Within 24 Hours
Our engineers review your stainless steel tube fitting request or drawing. You receive a specific quote within 24 hours.
Production
Standard lead time for stainless steel tube fittings is 30 days. Custom designs are sampled before the full production run.
Delivery
We ship stainless steel tube fittings by sea, air, or express courier. A tracking number follows once the order ships.
We support small-batch and prototype runs with no hard minimum order quantity. A first prototype run is typically around 100 pieces.
Often Ordered Together
Ready to Source Stainless Steel Tube Fittings?
If you already have drawings, email [email protected] directly and we will quote from them.
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