In conversations with customers, we sometimes use the expression "I want a tap of Sambu."
Sambu is one of the so-called industry terms, and the size of the screw expressed in inches may be expressed as "○○bu".
1/8 = Ichibu (1 minute)
1/4 = 2/8 = Nib (2 minutes)
3/8 = Sambu (3 minutes)
1/2 = 4/8 = Yeonbu Sibu (4 min.)
The numerator when the denominator is divided into 8 is called by adding a "bu".
In addition, as a way to express the fine size, "厘 (rin)" is used.
1 minute = 10 厘.
In terms of larger size and smaller size ,
1-3/4 = inch rokubu (1 inch + 6/8 so )
1/16 = Gorin (because half of one is 5 厘)
5/16 = Nibgolin 5/16 = 2/8 + 1/16 ( 2 minutes + 0.5 minutes (= 5 厘)) )
In addition to PT, there are also PF and PS screws that represent size in inches, as well as Rc, G, and Rp of the new JIS standards.
There is also the possibility of NPT for American-type pipe screws.
Unified screws and wit threads are also inches size , so some people also describe them as "○○b".
In other words, if you are told "sambu", you need to check the type of screw because there are all the possibilities.
By the way, 1 inch = 25.4mm.
In the same way for pipe screws, there are cases where the size is expressed in inches as "○○b".
The screws and tools for the actual pipes are of a separate standardized size.
In conclusion, when identifying screws, you can avoid unnecessary troubles by carefully checking the "type of screw", " size ", and "pitch".