Tube Selection
Correct tube selection is essential to the performance of Twin Ferrule tubing systems.
When selecting tubing material, size and wall thickness, the customer must consider pressure, flow, temperature, environmental and general system compatibility
Consideration in selection of tube
1. Quality of the tube materials & manufacturing method.
2. Wall thickness and outer diameter of tube.
3. Surface treatment of tube .
4. Hardness of tube.
5. Concentricity of tube.
Tube Quality Requirements for different materials
Carbon steel tubing
ASTM A179 or equivalent.
Carbon steel tubing for an oil pressure usage of high quality, annealed and seamless.
Maximum hardness : HRb72.
Tubing must be free from scars and shall be suitable for bending and expansion work.
Copper tubing
ASTM B65, B75 or equivalent.
Copper tubing of high quality, annealed and seamless.
Stainless steel tubing
ASTM A213, A269 or A632 or equivalent.
Stainless steel tubing for an oil pressure usage of high quality, annealed and seamless.
(316, 304, 321,etc.)
Hardness : below HRb 80.
Tubing must be free from scars and shall be suitable for bending and expansion work.
Monel tubing
ASTM B165 or equivalent.
400 alloy tubing of high quality, annealed and seamless.
Hardness : below HRb 75.
Tubing must be free from scars and shall be suitable for bending and expansion work.
Coefficient of Tubing to calculate Temperature/Pressure Change.
Multiply the allowable working pressure by the coefficient in the Table below in order to calculate allowable pressure at high temperature.
Example
SUS316
3/8” O.D tube X 0.049” wall thickness
1200oF:4800 psi X 0.37 = 1776 psi
The maximum working pressure of SUS 316 tubing for wall
thickness, 3/8” O.D X 0.049”, is 1776 psi at 1200°F
Tube Bending
When bending tube adjacent to SUPERLOK fittings, there should be sufficent linear distance from the bending point to the fitting.
See table below for guidance.
L: The straight line length of tubing from the end part of tubing to the beginning part of bending
ALSO AVAILABLE | FLEXIBLE METALLIC HOSES
Social