The threads are rounded equally at crests and roots by circular arcs ending tangentially with the flanks where r ≈ 0.1373 P The standard ISO 7 - Pipe threads where pressure-tight joints are made on the threads consists of the following parts: Please use a suitable tool to fasten and remove the fittings through the outer hexagon or inner hexagon of the fitting body. When tightening the fittings threads, please refer to the recommended torque amount listed in the recommended torque values information above. If the torque amount exceeds the recommended value, it can cause stress to the threads and may cause the fitting to break, or the gasket to deform and cause the fitting to leak. The size was originally based on the inside diameter, measured in inches, of a steel pipe for which the thread was intended. This is the source of the confusion, as people incorrectly think the size refers to the outside diameter of the male thread.

Below is a summary of the common BSP thread sizes in used with cast iron radiators and their corresponding actual outside diameters in millimetres. The actual outside diameter is what you can measure when looking at a valve tail, a threaded nipple, reducing bush or an opening in the radiator. BSP Sizes In Millimetres Nominal The standard ISO 228 - Pipe threads where pressure-tight joints are not made on the threads consists of the following parts: G is the international standard shorthand for BSPP - BSP Parallel threads. R is the standard for BSPT - BSP Tapered. Parallel (G) threads are used where the seal is made on a mating face, like inside a cast iron radiator with the aid of a gasket. Tapered fittings achieve a tight thread-to-thread seal with the help of a little sealant such as PTFE tape or hemp and Boss White. Right first timeUsing the table below we can see that a thread measuring 1/2" is actually a 1/4" BSP thread. Similarly, a thread In Europe Metric (DIN) pipe threads are common on German machines. These generally have a 1.5mm thread pitch, although They have been designed to join piping systems by coupling thread ended pipes and accessories available as male thread and female thread connector types and a selection of thread standards to choose from e.g.: BSP, NPT or G. Threaded joints are mainly used on smaller diameters pipes in non-critical applications such as domestic oil, gas, air conditioning, heating ventilation installations but can also be seen in pneumatic, automotive applications. Common types of threaded fittings are 90° elbows, 45° elbows, tees, straight fittings, square head plugs, hex head plugs, reducers, adaptors, flanges, caps, bushings. Threaded fittings systems ensure leak-tight connections in all low-pressure, low-temperature installations where vibration is not encountered. What does DZ on brass fittings mean? Taper threads, British Standard Pipe Taper thread (BSPT). These are sometimes denoted by the letter R, for example R 1/2" means a taper 1/2 inch BSP thread.

In Japan JIS tapered and parallel threads are common and are interchangable with the respective BSPT and BSPP threads,At certain sizes, NPT and BSP share the same number of threads per inch - at ½" and ¾" - but at all other sizes the two are quite different. The table below lists the TPI for both NPT and BSP at sizes commonly used with domestic radiators. Nominal British Standard Pipe ( BSP) is a set of technical standards for screw threads that has been adopted internationally for interconnecting and sealing pipes and fittings by mating an external ( male) thread with an internal (female) thread. It has been adopted as standard in plumbing and pipe fitting, except in North America, where NPT and related threads are used. Just to confuse things, often the T in BSPT refers to Thread and doesn't indicate either Taper or Parallel.

At least 41 thread sizes have been defined, ranging from 1⁄ 16 to 18, although of these only 15 are included in ISO 7 and 24 in ISO 228. [3] [4] [5] [6] The size number was originally based on the inner diameter (measured in inches) of a steel tube for which the thread was intended, but contemporary pipes tend to use thinner walls to save material, and thus have an inner diameter larger than this nominal size. In the modern standard metric version, it is simply a size number, where listed diameter size is the major outer diameter of the external thread. For a taper thread, it is the diameter at the "gauge length" (plus/minus one thread pitch) from the small end of the thread. The taper is 1:16, meaning that for each 16 units of measurement increase in the distance from the end, the diameter increases by 1 unit of measurement. DZ or DZR symbol stamped on brass components means that the part is dezincification resistant. Dezincification is a form of corrosion that can occur within a plumbing and heating system. How to measure bronze fittings? BES has all the steel fittings you need, from screwed stainless steel elbows to hose tail adaptors. Some of the most popular product types within this range would include: British Standard Pipe is the standard thread used on plumbing fittings across most of the world (but not in North America). Below, you'll find tables showing BSP sizes in mm; tables detailing the difference between BSP and the American standard NPT; an explanation of straight and tapered thread types; and a handy thread size ruler and template to print out and use at home.

PRESS FITTINGS

The nominal size refers not to the outside of the pipe, nor even to the outside of the thread, but to its internal bore - the inside of the tube where the fluid flows. It makes sense when sizing pipes for flow rate but it makes things confusing when measuring for replacement parts. BSP sizes don't match up with what you measure on the scale of a ruler, which can obviously cause some confusion. For example a 1/2 inch BSP thread (see above) actually measures more like 3/4 inch with a ruler. All Metric fittings are not supplied with any sealing equipment and require the use of PTFE/Teflon tape when being installed. Inch BSP - Bathroom basin taps and kitchen sink taps, radiator connections, shower hoses, old outside tap outlets, toilet cistern fill / float valves. In North America NPT, JIC and ORFS pipe threads are common. Some NPT threads are similar to BSPT threads so if in