Structure of food grade hose
Generally speaking, food grade hose has an inner rubber layer. It’s a synthetic rubber and it is to transfer the food like beer and milk. Then there is a wire or fiber braided reinforce in the hose. While it is to resist the pressure in the hose. The inner layer is mostly white, and the reinforce layer is one or more spiral steel wires. Last, there is a cover outside the reinforce. While that is to protect the reinforce from impact, wear and corrosion.
Working pressure
It is to ensure that the pressure of the hose and joint is greater than that of the system. Then the pulse or peak pressure in the system must be less than that of the food hose.
Test pressure
The test refers to the use of water or other suitable media. The food suction hose should be kept at double working pressure for 30 to 60 seconds. Then there should not be leakage and pressure drop. This test is according to ISO1402.
Burst pressure
It means that the pressure that causes the hose to rupture should be 4 times of the working pressure. But the burst pressure value in the product sample can only be for hose tests. And it can not be as a basis for hose selection.
Fluid compatibility
Food grade pipe and joint should fit the medium. Otherwise the system may not work properly or the hose will fail due to aging.
Temp range
In order to be immune to affect the property of the food safe pipe, the temp should be limit. That means the temp around can not exceed the temp range that the hose can bear. Otherwise the hose will age earlier and cause leaks.