Symbols or abbreviation
OP Option
R1/4 Taper pipe thread (external) 1/4 inch (formerly PT1/4)
Rc1/8 Taper pipe thread (internal) 1/8 inch (formerly PT1/8)
G1/4A Straight pipe thread (external) 1/4 inch (formerly PF1/4-A)
Rp1/8 Straight pipe thread (internal) 1/8 inch (formerly PS1/8)
Units
1. SI Units are used in this manual.
2. The following table shows the conversion of SI unit and customary unit.
Item SI unit Customary unit
Force
1 N 0.1020 kgf
(1 lbf) (0.4536 kgf)
Pressure
1 kPa 0.0102 kgf/cm
2
(1 psi) (0.0703 kgf/cm
2
)
Torque
1 N·m 0.1020 kgf·m
(1 lbf·ft) (0.1383 kgf·m)