Threaded Components
Threaded components are machined parts with specified internal or external threads, such as adaptors, connectors, threaded rods, inserts, nozzles and fittings, in metric, inch, pipe or special thread forms. Thread class, pitch and length are made and gauged to drawing.
What it is
Threads are cut by turning or tapping, rolled for strength and finish, or ground for precision. Pipe threads (BSP, BSPT, NPT) seal or connect fluid systems; trapezoidal and ACME threads transmit motion.
Threads are checked with go/no-go gauges to the specified tolerance class (for example 6g/6H).
Typical applications
- Hydraulic and pneumatic adaptors
- Pipe fittings and nipples
- Lead screws and nuts
- Threaded inserts and bushes
- Nozzles and connectors
Materials & grades
- Carbon and alloy steel
- Stainless steel
- Brass
- Aluminium
- Plastics
Points to consider
- Specify thread designation and tolerance class.
- Don't mix BSPT and NPT; they look similar but don't seal together.
- Rolled threads suit high-strength and fatigue applications.
- Use our Thread Finder to confirm thread details.
Frequently asked questions
Can BSP and NPT threads be mixed?
No. They have different flank angles and pitches for some sizes and will leak or damage each other.
How are threads checked?
With go/no-go plug and ring gauges to the specified tolerance class.
Where can I check thread dimensions?
Our free Thread Finder lists pitch, tap drill and diameters for 3,100+ thread sizes.