Views: 108 Author: Good Du Publish Time: 2023-03-08 Origin: Site
Threaded pipe fittings are used in a particularly wide range of fields, and there are many kinds. For most people, it is impossible to identify all kinds of threads clearly, and the classification of threads is not very clear. Therefore, mastering the basic knowledge of thread is helpful to facilitate our study and work in the construction manufacturing industry. This article will take you to understand the types and differences of thread, What are NPT BSP PT ? What are the differences between Metric Thread, British Standard Whitworth Thread and American Standard Thread?
A screw thread is a continuous raised spiral linear ridge made by winding in a spiral form around a cylinder or cone. The thread is divided into internal thread and external thread. Threaded pipe fittings are fastened or driven by connection of internal and external threads. The thread is external thread on the outer surface of the workpiece, such as common bolts or screws; Inside the workpiece is the internal thread, usually on the part to be assembled. A complete description of the thread should include at least five elements, thread form + nominal diameter + line number + pitch (or lead)+ spin.
Pipe Fitting Thread Types
Pipe Thread and Standard Thread Conversion Table
Common Pipe Threads Mainly Include the Following: NPT BSP PT
Here I will focus on the NPTThread, NPT is the abbreviation of National (American) Pipe Thread, belongs to the United States standard 60 degree taper pipe thread, NPT thread is a wide range of applications. NPT thread is general seal cylindrical pipe thread and general seal taper pipe thread. The theoretical position of the reference plane of the American general sealed taper external thread is located in the plane perpendicular to the thread axis and one reference distance (L1) from the small end.
Medium diameter of thread D2=d2=D-0.8*P
Thread path size D1=d1=D-1.6*P
Mode of Cooperation:
Cylindrical internal thread and taper external thread form a "column/cone" fit; Conical internal thread and conical external thread form a "cone/cone" fit.
The limit deviation of the datum plane axial position of the American seal taper thread is -P +P;
The minimum effective thread length of American general sealed taper external thread shall not be less than the actual size of its reference distance + the sum of assembly allowance;
The minimum effective thread length of American general sealing thread shall not be less than the sum of the actual deviation of the reference plane position + the basic size of the reference distance + the assembly allowance;
The complete marking of the general seal pipe thread in the United States: thread characteristic code, thread size code and turn code;
American general seal taper pipe thread characteristic code: NPT
American general seal cylindrical internal thread characteristic code: NPSC
BSP is the general code of British Pipe Thread, but there are three kinds of BSPP, BSPT and BSPF. BSPP is British cylindrical pipe thread code, only internal thread, equivalent to the domestic 55 degree cylindrical (parallel) pipe thread, and BSPT is a British taper pipe thread standard, refers to the thread thread Angle of 55 degrees, the thread has 1:16 taper, another is BSPF is British fine pipe thread. The front two are used for sealing joint and the back one is used for general joint.
PT is the abbreviation of Pipe Thread, is 55 degrees sealed taper pipe thread, belonging to the Wyeth thread family, mostly used in Europe and federal countries, often used in the water and gas pipe industry, taper 1:16. The marking of pipe threads consists of thread feature number (R) and dimension number. R1/2 indicates the R thread with 1/2 thread.
We(Shanghai Zhucheng Pipe Fittings Manufacturing Co Ltd) manufacture pipe fittings include NPT, PT, BSPP, BSPT and BSPF. The production of threaded pipe fittings are Threaded Elbow, Threaded Tee,Threaded Cross,Threaded Coupling,Threaded Cap, Threaded Union, Threaded Nipple, Swage Nipple,Hex Nipple, Plug,Bushing.