Hose Bend Radius and Pressure Definitions

Bend Radius Definitions

Quite often, users have questions when the subject of hose flexibility is brought up. Many different terms are used to describe this attribute of the product line. We are listing some formal definitions currently used in the hose industry.

Bend Radius (fluoropolymer hose and all rubber hose)
The radius of a bent section of hose measured to the innermost surface of the curved portion.

Bend Radius (metal hose)
The radius of a bent section of hose measured to the hose centerline .

Minimum Bend Radius
The smallest radius at which a hose can be used.

Metal Hose

Dynamic bend radius
The radius at which constant or continuous flexing occurs.

Static bend radius
The smallest fixed radius at which a hose can be subjected.

Force to bend
The amount of stress required to induce bending around a specified radius. Hence, a measure of stiffness.

Teflon tubing bend radius.

Pressure Definitions

Maximum Rated Working Pressure
The maximum pressure that the hose should be subjected to on a continuous basis

Maximum Rated Test Pressure
The maximum rated pressure is multiplied by 150% to determine the maximum rated test pressure

Nominal Rated Burst Pressure
The average pressure at which the core or braid will rupture at ambient temperature.

Pulsating or Shock Pressure
The performance of metal hose can be greatly reduced under this type of working pressure. Pressures are normally reduced by 50% in pulsating or shock pressure applications.

Pressure/Temperature Correction
Metal hose pressure capabilities decrease as the temperature increases. Consult the temperature correction factor table which determines pressure ratings at elevated tempertures.

Pressure Drop
Pressure drop occurs in long hose runs. The amount of pressure loss in a metal hose is approximately 3 times that of steel pipe.