Stainless Steel Pipe Ends: Plain, Beveled, Threaded and Grooved Buyer Guide

Stainless steel pipe ends determine how the pipe connects at site — and picking the wrong end type is one of the most common reasons a shipment arrives but cannot be installed. Butt-welding requires a beveled end, threaded connections require NPT taper threads, and grooved systems require rolled or cut grooves. This guide covers the four main stainless steel pipe end types, the relevant standards, and what to specify on your RFQ so the supplier delivers exactly what your fabrication or installation crew needs.

Why pipe end preparation matters

Stainless steel pipe is supplied in random lengths (typically 5.5–6.5 m) and the ends are cut at the mill to one of several standard preparations. The end type dictates the joining method: weld, thread, grooved coupling, or plain-end coupling. If you order beveled ends but your crew expects plain ends for grooved couplings, the pipe cannot be used without re-machining, which adds cost and lead time.

1. Plain End (PE)

A plain end pipe is cut square with no bevel or thread. It is the default for pipe that will be welded in the field with a backing ring, or for systems using compression fittings, press fittings, or flanges welded on site. Plain ends are cheaper than beveled or threaded ends and are commonly specified for small-diameter tubing and instrumentation lines.

Best for: sanitary and tubing applications, press-fit systems, flanged spools where the flange is welded on at the fab shop.

2. Beveled End (BE) — for butt welding

Beveled ends are machined to a 37.5° bevel per ASME B16.25, with a small root face (typically 1.6 mm) to ensure complete penetration during butt welding. This is the standard end preparation for all buttweld fittings and pipe used in process piping, power, and oil & gas.

The bevel is applied by the mill or the processor, and the angle must be consistent so the welder can achieve the required joint. Wall thickness affects the bevel geometry: heavier wall pipes may require a compound bevel. For pipe wall thickness above about 16 mm, a double V or compound bevel is often specified.

Best for: buttweld piping systems, process piping, any joint that must be 100% radiographed. To understand the difference between the pipe itself and fittings, see our seamless vs welded stainless steel pipe guide.

3. Threaded End (TE) — NPT

Threaded ends carry NPT (National Pipe Taper) threads per ASME B1.20.1, with a 1:16 taper. Threaded stainless steel pipe is typically limited to NPS 2 (DN 50) and smaller, because larger diameters are more reliably joined by welding. Threaded joints require thread sealant (PTFE tape or thread compound) and are not suitable for high-pressure or high-temperature service where leakage cannot be tolerated.

Stainless steel threads can gall during make-up, so anti-seize compound is recommended. Threaded ends are commonly found in instrumentation lines, gas systems, and utility piping.

4. Grooved End

Grooved ends have a circumferential groove rolled or cut near the pipe end, designed for grooved mechanical couplings (Victaulic-style). Grooved systems are fast to install and allow disassembly, which makes them popular in HVAC, fire protection, and water systems. The groove dimensions are specified by the coupling manufacturer (e.g., Victaulic grooves).

Grooved ends are not typically used for stainless steel process piping but are common in stainless HVAC and chilled water lines.

Quick reference: pipe end types

Plain End (PE) — square cut; for press fittings, flanges welded on site, tubing.
Beveled End (BE) — 37.5° bevel per ASME B16.25; for butt welding.
Threaded End (TE) — NPT taper thread per ASME B1.20.1; NPS 2 and smaller.
Grooved End — rolled or cut groove; for grooved couplings (HVAC, fire protection).

How end preparation relates to wall thickness

The bevel geometry depends on wall thickness. Schedule 10S thin-wall pipe uses a simple 37.5° bevel, while Schedule 80S and heavier wall may need a compound bevel to ensure full weld penetration. When you specify the pipe, you should already know the wall thickness — see our Schedule 10S/40S/80S wall thickness guide to select the right schedule for your pressure rating.

Buyer’s RFQ checklist for pipe ends

Specify the end type explicitly: plain end, beveled end, threaded end, or grooved end.
For beveled ends: reference ASME B16.25 and confirm the bevel angle and root face.
For threaded ends: specify NPT (or BSPP/BSPT if required), and the pressure class.
For grooved ends: specify the groove standard or coupling manufacturer model.
State the grade (304/304L/316/316L), schedule, length, and whether ends are machine-cut or saw-cut.
Request mill test certificate to EN 10204 3.1 — see our MTC buyer checklist.

Common mistakes to avoid

Ordering pipe without specifying the end type — the mill’s default may not match your joining method.
Assuming all pipe comes beveled — small diameter tubing is commonly plain end.
Ordering threaded ends on NPS 3 and larger — threaded joints above 2 inches are impractical.
Forgetting that beveled ends can be damaged in transport — specify bevel protectors if needed.
Not confirming the thread standard (NPT vs BSP) — they are not interchangeable.

Send us your pipe size, schedule, grade, and required end preparation, and SOROYA will confirm the correct end type, quote the pipe with mill test certificate, and arrange delivery to your site.

SOROYA PTE. LTD.
Email：nancy@soroya.com.sg
WhatsApp：+65 8058 3416