A pinch weld seal is a U-shaped rubber channel that grips the folded sheet-metal flange (the pinch weld) around a car door, trunk or hatch opening, with a sponge bulb that the door closes against. It is chosen by three things: grip range (flange thickness, e.g. 1–2 mm or 2–4 mm), bulb position (top or side) and bulb size. It pushes on by hand – no glue – because a steel clip carrier inside the channel holds it on the flange.
What is a pinch weld?
Where two body panels meet around a door or trunk opening, they are spot-welded together into a thin flange that sticks out from the body. That flange is the pinch weld. A pinch weld seal covers the sharp edge and seals the door against it.
Top bulb or side bulb?
| Type | Shape | Use |
|---|---|---|
| Top bulb | Bulb sits above the channel | Door closes onto the top of the flange – trunks, hatches, some doors |
| Side bulb | Bulb sits beside the channel | Door closes against the side of the flange – most car door openings |
| No bulb (edge trim) | Channel only | Covering edges where nothing closes against it |
Copy the original seal: the bulb must sit where the door edge lands.
How do I choose the grip range?
Measure the total flange thickness, including paint and any trim, at several points. Choose a seal whose grip range has that thickness near the middle – for a 2 mm flange, a 1–3 mm seal rather than a 1–2 mm one. See the grip range guide.
What is a pinch weld seal made of?
The bulb is EPDM sponge (soft, closes the gap) and the channel is solid EPDM or PVC over a steel clip carrier. EPDM is the better choice for vehicles: it handles UV, ozone and about –40 °C to +120 °C.
How do I order?
Send a photo of the cut end next to a ruler, flange thickness, bulb position and the length you need. Universal pinch weld seals are supplied from 10 m; indicative FOB prices start from US$0.10/m. See car door seals, pinch weld seal with side bulb and edge trim with top bulb.
Quick questions
Do pinch weld seals need glue?
No – the steel clip carrier grips the flange. Press it on by hand or with a rubber mallet, starting at the bottom centre of the opening.
Need a seal for this?
Send your section, gap size or a photo of the old seal – Dora replies usually within 2 hours. Automotive weatherstrips are available from 10 m.