PEEK is UL94 V-0 as it comes: the PEEK from our material supply burned 12 s in total at 3.2 mm and 42.1 s at 1.5 mm, against a 50 s limit. The bar-by-bar data, the heat limits and when PEEK is worth its price are below — and the part can be machined from 1 piece.
EKINSUN machines PEEK parts to drawing or from a sample in our own CNC factory, from 1 piece — operating handles, insulators, bushings, valve seats and interlock parts for electrical equipment. PEEK is chosen when one plastic part has to take heat above 150 °C, carry a load and meet UL94 V-0 at the same time.
Is PEEK UL94 V-0? Yes, without flame-retardant additives. Five 3.2 mm bars of the PEEK from our material supply burned 12 s in total and five 1.5 mm bars 42.1 s, against the 50 s V-0 limit.
Unfilled PEEK has a density of 1.30 g/cm³, a tensile strength of about 100 MPa, a glass transition at 143 °C and a melting point of 343 °C. Above 143 °C it keeps its shape but loses stiffness, which matters for parts that carry load hot.
| Property | Value |
|---|---|
| Density | 1.30 g/cm³ |
| Tensile strength | about 100 MPa |
| Glass transition (Tg) | 143 °C |
| Melting point (Tm) | 343 °C |
| Flame rating | UL94 V-0 — test data below |
| Flame retardant added | None needed |
Property values are typical for unfilled PEEK. Glass- or carbon-filled PEEK is stiffer and has other values; name the grade on the drawing if it matters.
PEEK from our material supply was burn-tested in two batches by independent laboratories, by the UL94 vertical method, and both batches rated V-0. Each batch is five bars, each bar flamed twice for 10 seconds.
| Bar | t1 (s) | t2 (s) | t3 (s) | t2 + t3 (s) | Burned to clamp | Cotton ignited |
|---|---|---|---|---|---|---|
| Bar 1 | 3.1 | 4.6 | 0.3 | 4.9 | No | No |
| Bar 2 | 3.6 | 8.7 | 0.4 | 9.1 | No | No |
| Bar 3 | 5.9 | 3.9 | 0.2 | 4.1 | No | No |
| Bar 4 | 3.4 | 2.0 | 0.5 | 2.5 | No | No |
| Bar 5 | 3.9 | 3.0 | 0.2 | 3.2 | No | No |
| Total t1 + t2, 5 bars | 42.1 s (V-0 limit 50 s) |
| Bar | t1 (s) | t2 (s) | t2 + t3 (s) | Burned to clamp | Cotton ignited |
|---|---|---|---|---|---|
| Bar 1 | 0 | 2 | 2 | No | No |
| Bar 2 | 0 | 3 | 3 | No | No |
| Bar 3 | 0 | 2 | 2 | No | No |
| Bar 4 | 0 | 3 | 3 | No | No |
| Bar 5 | 0 | 2 | 2 | No | No |
| Total t1 + t2, 5 bars | 12 s (V-0 limit 50 s) |
At 3.2 mm the PEEK never kept burning after the first flame and stopped within 3 seconds after the second. At 1.5 mm the longest single after-flame was 8.7 seconds against the 10-second limit and the five bars together burned 42.1 of the 50 seconds allowed — still V-0, with less margin. PEEK walls under 1.5 mm should be discussed before ordering. What V-0, V-1 and V-2 require is set out in the UL94 rating chart.
Need a PEEK part for a panel or a hot, loaded duty? Send the drawing or the old part. EKINSUN machines PEEK from 1 piece in our own CNC factory; runs of several hundred can also be injection-moulded at our partner factories. The more pieces, the lower the unit price. Quote within 12 hours.
Machined PEEK starts at 1 piece and holds machined tolerances on every face; injection moulding pays off from several hundred identical parts, because the mould is paid for once.
| Machined from rod or plate | Injection-moulded | |
|---|---|---|
| Quantity | From 1 piece | Usually several hundred and up, to pay for the mould |
| Where | Our own CNC factory | Partner factories |
| Colour | Natural (beige), black or red | Natural, black or red; other colours on request |
| Tolerances | Machined tolerances on every face | Set by the mould |
PEEK costs several times as much as PA66 or POM, so it earns its place only where heat, load and the flame rating meet in one part. The table sorts the common cases.
| Your duty | PEEK needed? | Cheaper choice |
|---|---|---|
| V-0 only, below 120 °C, light load | Usually not | Flame-retardant PA66 or PBT — see the UL94 chart |
| V-0 and above 150 °C | Yes, or PPS | PPS where impact load is low |
| Wear part, no flame rating, room temperature | No | POM or PA6 |
| Gear or plate carrying the mechanism load | Often no | Steel, machined and zinc-plated — see custom spur gears |
| Insulating part next to a hot coil or busbar, under load | Yes | — |
Replacing parts of a mechanism that is no longer made? Send the old parts — plastic and metal — or photos with caliper readings. We machine the plastic parts in PEEK and the gears and plates in zinc-plated steel, matched as a set, from 1 piece; quote within 12 hours. See parts made from a sample.
Yes. Besides natural (beige) and black, PEEK parts can be made in red — machined from 1 piece or moulded in larger runs. Name the colour on the drawing or in the enquiry.
The data for the PEEK from our material supply is a UL94 vertical-burn test result, not a UL listing. If you need a UL-listed grade, say so in the enquiry and the grade is chosen for it.
Related pages: UL94 rating chart for plastics; engineering plastics comparison chart; plastic trade names; plastic bushings and bearings; nylon machining.
Yes. PEEK reaches UL94 V-0 without added flame retardant; test bars of the PEEK from our material supply rated V-0 at 1.5 mm and 3.2 mm.
PEEK has its glass transition at 143 °C and melts at 343 °C; above 143 °C it keeps its shape but loses stiffness under load.
Yes. EKINSUN machines PEEK from 1 piece, from a drawing, a sketch or the old part, quoted within 12 hours.
Yes. Besides natural (beige) and black, PEEK parts can be made in red — machined from 1 piece or moulded in larger runs.
The data for the PEEK from our material supply is a UL94 vertical-burn test result, not a UL listing. If you need a UL-listed grade, tell us in the enquiry.
2 tables on one printable sheet: PEEK UL94 burn data at 1.5 mm and 3.2 mm, bar by bar.
Download PDF ↓Quote within 12 hours: drawing, sketch or the old part, the duty and the quantity.
// PEEK in short
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Handles, insulators, bushings, seats and interlock parts in PEEK, machined to drawing or from the old part — from 1 piece, quote within 12 hours.