JIS Flanges Bolts Nuts

Overview

Engineering reference data for JIS Flanges Bolts Nuts in piping systems.

Key Formulas

Continuity

$A_1 v_1 = A_2 v_2$

Mass conservation in pipe flow.

Pressure Drop

$\Delta P = f \frac{L}{D} \frac{\rho v^2}{2}$

Darcy-Weisbach equation.

Pipe Area

$A = \frac{\pi D^2}{4}$

Cross-sectional area of a pipe.

Variables

JIS Standards by Engineering Division

The Japanese Industrial Standards (JIS) for flanges, bolts, nuts, and gaskets are organized by engineering divisions under the Japanese Standards Association (JSA).

B. Mechanical Engineering

Fasteners:

Shaft Couplings:

Pipe Flanges - Calculation Basis:

Pipe Flanges - Dimensions:

Hydraulic Flanges:

Gaskets:

F. Shipbuilding

Other Divisions

Pressure Rating Standards

The 5K, 10K, 20K, and 40K designations in Japanese marine standards refer to pressure classes in kgf/cm². For reference:

$1 \text{ kgf/cm}^2 = 98.0665 \text{ kPa} \approx 0.098 \text{ MPa}$

Common marine pressure classes:

• 5K: ~0.49 MPa (low pressure applications)
• 10K: ~0.98 MPa (standard duty)
• 20K: ~1.96 MPa (medium pressure)
• 40K: ~3.92 MPa (high pressure hydraulic)

References

• Original Source