Bulkhead fittings look simple until a panel weeps on the customer’s line. In OEM work the geometry is forgiving only when the print states hole size, seal method, and thread form clearly. This note walks through common field failures and the drawing callouts that prevent them.
Browse current parts in our bulkhead fittings category, or compare mating hardware in fasteners when the nut stack is custom.
Leak paths that show up after install
- Hole oversized for the seal land
- Wrong washer / O-ring stack for panel thickness
- Taper thread used where a face seal was intended
- Nut bottoming before the seal compresses
Each of these can pass a casual visual check and still fail pressure test. Put the seal stack on the drawing, not only in an email.
Thread and wrench details worth freezing
Call out the standard (NPT, BSPP/G, metric, UN, etc.), engagement length, and hex size. If assemblers reuse existing tools, say so. Mixed standards across a BOM are a frequent cause of “it almost threads.”
Material choices next to tanks and panels
Carbon with plating is common indoors; stainless is safer for washdown or outdoor exposure. If you are undecided, start from the media and environment, then review related carbon steel fittings or stainless fittings.
What to send with the RFQ
PDF + STEP, hole/panel notes, first-lot quantity, and annual volume. Submit via Contact and email drawings afterward. For broader OEM process options, see OEM / ODM.
Frequently asked questions
01Can you reverse-engineer a bulkhead from a sample?
Yes for many designs. We measure, propose a drawing, and wait for your approval before mass production.
02Do bulkhead nuts need to be quoted with the fitting?
Preferred when the thread and stack are special. Matching gauges and materials reduces assembly surprises.