Fluid, piping & valves
Bulkhead unions and crosses
Bulkhead unions, bulkhead reducing unions and tube crosses for passing instrumentation tubing through panels and enclosure walls and for four-way branching, in stainless steel twin-ferrule designs.
Overview
A bulkhead union has a long threaded body that passes through a panel hole and is held by a locknut, with a tube connection on each side. It is used where tubing enters instrument cabinets, analyser shelters and control panels. Reducing versions change tube size across the panel, and bulkhead male connectors give a threaded port on one side. Crosses provide four tube connections at one point. The stainless steel bulkhead union in the source range uses the twin-ferrule arrangement of nut, back ferrule, front ferrule and body, in sizes 1/4 in to 1 in.
Selecting bulkhead fittings
Give the tube outside diameter on each side, the panel thickness and the hole size if fixed. Choose stainless steel or another alloy to suit both the media inside and the environment around the panel. For reducing bulkheads, state which size goes on which side.
Range overview
- Types and variants
- Bulkhead Unions
- Bulkhead Reducing Unions
- Bulkhead Male Connectors
- Union Crosses
- Materials and grades
- Stainless Steel
- Mild Steel
- Carbon Steel
- Size range
- 1/4 in to 1 in (Bulkhead Union)
- Bulkhead Male Connector: 1/2 in, 3/4 in, 1 in, 2 in
- Pressure / temperature
- 1 bar to 600 bar (stainless steel bulkhead union)
- Connections and interfaces
- Twin-Ferrule Tube End
- NPT
- BSP
- Features
- Locknut Panel Mounting
- Four-Part Twin-Ferrule Design
Exact specifications depend on the variant, material and size. Confirm ratings and certification against the datasheet or with our engineers before ordering.
Applications
- Instrument Panels and Cabinets
- Analyser Shelters
- Chemical Lines
- Water Lines
- Gas Lines
Industries
- Oil and gas
- Chemical
- Power generation
Information that speeds up a quotation
Share what you know. Anything you are unsure of can be marked “not known” — our engineers will help confirm it.
- Tube OD
- Wall thickness
- Connection
- Material
- Pressure
- Temperature
- Media
- Standard
- Test certificate
Need a datasheet?
Add this family to your enquiry list and mention the variant — we will send the relevant technical documents.
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Related solutions and guides
Frequently asked questions
What do I need to specify for a bulkhead union?
Give the tube outside diameter on each side, the panel or wall thickness, the material, and the line's working pressure, temperature and media. For a reducing bulkhead, say which side carries the larger tube. Quantities and any documentation requirements complete the enquiry.
Can other materials be supplied for corrosive environments?
Stainless steel is standard. Duplex and super duplex stainless steels and nickel alloys are listed as possible materials on request. Tell us the media and the surrounding environment so material suitability can be discussed and confirmed at quotation stage. Material certificates can be requested with the order.
Ready to specify bulkhead unions and crosses?
Send the details you have — quantities, sizes, drawings or a part number. Unknowns are fine.