BSP or NPT? What’s the difference and how do I choose the right one?
BSP, or BSPP, stands for British Standard Pipe Parallel and is a straight, cylindrical pipe thread. NPT, which stands for National Pipe Thread, is a tapered pipe thread.
There is also BSPT, which stands for British Standard Pipe Tapered, which is also tapered, but it is used very rarely.
When we talk about standard solutions in Sweden, for example within plumbing and HVAC, exclusively BSP threads are used today. NPT threads can be found on other products, often products from the United States and Australia, but we almost always use BSP. However, we can supply NPT if required.
Q&A
How much pressure can threaded connections withstand?
Very high pressure. In industry, threads are usually used for simpler and smaller applications, but they can handle very high pressures if the correct standard and size are selected.
Example: Threaded fittings can be used in hydraulic systems. Threaded hydraulic connections are very common, and a typical hydraulic system in, for example, an excavator operates at a pressure of approximately 200–300 bar.
Is DN50 the largest threaded connection?
No, but threaded connections are often no longer used above DN50. There are DN100 threaded valves available, but they are impractical to work with because they become heavy and difficult to handle. As a general rule of thumb, threaded connections are used up to DN50.
When is it appropriate to choose a threaded connection?
There is no general answer, as the choice depends on the system design and the specific application. Threaded connections are mainly suitable for single connections in smaller dimensions, especially when the installation is relatively simple and when there are no special requirements. Please contact us if you are unsure about what you need.
Are BSP threads always ISO pipe threads?
BSP threads usually follow ISO standards, as these dimensions generally provide the best fit.