When the Pipe Adapter Isn't on Any Shelf
Standard plumbing adapters cover the common sizes. The one you actually need is often the one no merchant stocks: an imported BSP port that has to meet an American NPT line, an odd reducer, an oversized fitting, or a thread on an old appliance no one makes anymore. You know exactly what should connect — you just can't buy the piece that joins it.
EKINSUN machines that piece. We make custom plumbing thread adapters, male to female, in any size and reducer combination, in lead-free brass for potable water or 316 stainless for corrosive lines — single pieces through small production, with a quote in 24 hours.
Need a higher-pressure hydraulic build instead? See hydraulic adapters. Pure thread-standard conversion across all engineering threads? See thread adapters.
BSP ↔ NPT, Male to Female — and Everything Between
The conversions and forms plumbers, installers and OEMs ask us for most:
| Conversion / form | Typical use |
|---|---|
| BSP ↔ NPT | British pipe thread (BSPP/BSPT) to American NPT on imported pumps, valves, heaters and machinery |
| Male ↔ female | Any gender on each end — male-to-female, female-to-female, male-to-male |
| Reducers & odd sizes | Step a 1" down to 3/4", or oversized/fractional sizes no catalogue carries |
| Old / obsolete threads | Legacy imperial and discontinued plumbing threads reproduced from a sample |
BSP and NPT don't simply screw together — BSPP is parallel and seals on a washer or O-ring face, while NPT (and BSPT) is tapered and seals on the thread. We machine the correct sealing feature on each end so the joint actually seals, instead of forcing a leak-prone mismatch.
Build Your Adapter Spec — Instant RFQ
Configure your plumbing adapter below. It generates clean RFQ text you can copy, or send straight to our engineers — no account, no CAD file.
Plumbing Thread Adapter Configurator
Define both ends, material and quantity. We reply with lead time and pricing within 24 hours.
Custom plumbing adapter…
Materials for Plumbing Adapters
Lead-free brass
The default for potable water and general fluid lines — easy to seal, corrosion-resistant, drinking-water safe on request.
Ask about brass →316 stainless
For corrosive, chemical, marine and high-purity lines where brass isn't suitable.
316 machining →Bronze & specials
Bronze for marine and dezincification-resistant needs, or other alloys to suit your line.
Discuss material →No Drawing? We Reverse Engineer It
Send the fitting or the two threads
The old adapter, both parts it must connect, or the thread on each end — even a worn or corroded sample.
We measure & draw it
Threads, seal face and bore captured; we rebuild the CAD for free. How it works →
Confirm, then machine
You approve the drawing, then we turn and inspect it. Copy from a sample →
What to Send Us
- The sample fitting, or both parts it must connect — or photos with one known dimension
- The thread on each end if you know it (e.g. 1" BSP male to 3/4" NPT female)
- Medium (drinking water, hot water, gas, chemical) and pressure
- Whether the line needs lead-free / potable-safe material
- Quantity — one to prove the fit, or a batch — and delivery country
No CAD, no problem. Rebuilding the drawing is our job — free, and confirmed with you before anything is cut. See how to order with no CAD file.
Frequently Asked Questions
Yes — our core job. If the size, reducer combination or thread isn't a stock item, we machine it to your spec. Give us the thread on each end (e.g. 1" BSP male to 3/4" NPT female) or send a sample, and we make the adapter that fits and seals.
Yes. We machine BSP (BSPP parallel / BSPT tapered) to NPT in any male/female combination. BSPP seals on a washer or O-ring face while NPT seals on its taper, so we machine the correct sealing feature on each end rather than forcing a mismatched fit.
We machine plumbing adapters in lead-free brass for potable-water lines on request. Tell us it's for drinking water and we select a lead-free alloy; for highly corrosive or chemical media we use 316 stainless instead.
Yes. Old imperial, obsolete or non-standard plumbing threads are no problem — send the part, even worn, and we measure the thread, bore and sealing face, rebuild the drawing free, then machine a compatible replacement. No drawing or part number needed.
From small fractional sizes up to large oversized fittings, and from a single piece or prototype to small and medium batches. No strict MOQ — a one-off repair adapter is welcome.
Get a Plumbing Adapter Quoted
A sample or the two threads — that's all we need. Engineers reply in 24h.