The purpose of the test is to verify the integrity of the inner liner.
- Clean the gasket with water.
- Place a translucent background of sufficient thickness at each end.
- Evacuate the value of 0.85 bar for 10 minutes.
- Monitor using a light source inside the hose and identify any changes in behaviour and defects.
- Record and compare the state of the inner liner with observations made during visual inspection.
On-site Hydrostatic Test
- Check the tightness of the hose at a pressure generally higher than in operation.
- Verify the behaviour of the hose structure: elongation ; deformation dilation.
Note: The hose is in position right on planks, metal pipes ....., so as to elevate the flanges of the floor and release the flexible constraints.
- Fill with water and drain thoroughly hose lifting the drain side end (air pocket).
- Mounting pressure to 0.7 bar and hold 5 min. Taking the length measure of the hose (L0).
- Increase the pressure from 0.7 bar to half of the working rated pressure. Take 30 minutes and reduce pressure 0.7bars.
- Increase the pressure from 0.7 bar to the working rated pressure. Hold 5 min and measure the length of the hose (L1).
- Decrease the pressure to 0 bar and take 15 minutes.
- Increase the pressure to 0.7 bar, and measure the length of the hose (L2).
L1 - L0 / L0 = temporary extension
L2 - L0 / L0 = permanent elongation
These values will be identified and compared with those measured in factories. For a temporary or permanent elongation greater than 2%, the hose should be removed from service.