We understand that customers may sometimes be uncertain as to whether our compressed air nozzles have American or European threading, or both. Regardless of your preference, we are able to supply both types.
The following overview is intended to clarify what the (optional) NPT and BSP connections are all about.
If you have any doubts about the suitability of our products for your specific application, please do not hesitate to contact us. We are here to help.
American nozzles for our customers in Europe
- The most important first: Almost all our air nozzles are supplied with a European BSP inch thread (British Standard Pipe, Whitworth thread).
- A tapered NPT inch thread (National Pipe Thread) is also available on request.
- For your convenience, the part numbers in our shop have a BP prefix, e.g. BP1230. In this way we mark all variants with a BSP thread so there is no risk of confusion.
- Please note: If you order an EXAIR product from us or elsewhere without the BP suffix, it will probably be supplied with an NPT connection! This is because in the USA, where the nozzles are manufactured, NPT is the standard.
NPT or BSP – nothing to worry about!
- Many of our EXAIR nozzles with a “BP” part number have a factory milled BSP thread. This includes the majority of our vortex tubes, our cabinet coolers and some of our air nozzles.
- If an EXAIR product is made without a BSP connection, the right air adapter is always included.
- The adapters in question possess two external threads (NPT and BSP). You can attach them to the compressed air line using standard fittings.
1/4″ compressed air adapter with one NPT and one BSP male thread
The difference between BSP male and female threads
A BSP external thread (male) is a conical, tapered inch thread. It belongs to the group of R threads, shortened BSPT (T = taper). For the thread standard, please refer to DIN EN 10226 (previously DIN 2999): BSPT Whitworth Tapered Pipe Thread DIN EN 10226-1 and DIN EN 10226-2
A BSP internal thread (female) is characterised by a parallel shape. Therefore it is designated a G thread, otherwise known as BSPP (P = parallel). For further information, please refer to DIN ISO 228 (DIN 259): BSPP Whitworth Pipe Thread DIN ISO 228 (DIN 259)
Proper sealing is always important.
Whether it is a BSP, BSPP or NPT thread, it is always a good idea to apply a sealing tape around the thread. This can compensate for the differences with a metric G thread quite well to a certain extent.
Problems with connecting BSPT and NPT to metric and other threads (e.g. plastic pipes) occur when they are repeatedly screwed on and off. This damages the threads, causing leaks.
And what does metallic sealing mean?
A metal-to-metal seal is a method of joining two metal surfaces together to form a sealed unit. This process does not require the use of additional sealing materials. Metal is known to be highly resistant and durable. This makes it an ideal choice for applications where high temperatures or pressures are present. However, it is important to consider the type of thread.
- Tapered threads form a seal without additional sealant. This is possible because the male and female threads wedge into each other when tightened.
- Parallel threads require aids (O-ring, washer) to ensure a tight connection.
These compressed air adapters are made of a zinc-copper alloy (brass).
Depending on the specific requirements, there are different materials that are suitable for metallic seals.
- Stainless steel is very resistant to corrosion and high temperatures.
- Copper offers good thermal conductivity and resistance to many chemicals.
- Aluminium is lightweight and corrosion resistant. However, it is less heat resistant than stainless steel.
- Nickel alloys can withstand high temperatures and aggressive chemicals.
For general information on thread types, visit: International Thread Standards
Do you have a specific question about compressed air connections?
Our dedicated technical support team will be happy to help.