422
T. Sundararajan et al.
Fig. 1 Measurement setup
This collectively infers that the PRV should not open below 180 psi and should not
bleed below 155 psi.
However, the initial prototype testing had an opening PRV pressure of 180 psi
and the PRV stopped only at 130 psi. Hence, measures to increase the blowdown
pressure was taken to bring it up to 155 psi.
4.3 Testing for Unbalance
The dynamic unbalance of the wheel was checked before the installation of PRV
and rechecked after mounting the PRV. The value of unbalance had a significant
improvement in the wheel level inspection. This will reduce the amount of the additional balance weight which needs to be placed in a wheel-tire assembly while fitting
in the vehicle.
5 Improvement Actions
5.1 Problem Statement
The blowdown pressure of the PRV is too low—130 psi, and it needs to be increased,
such that the PRV does not release any pressure below 155 psi. This has to be done
keeping in mind that this PRV is purely a mechanical device, and it operates entirely
based on spring action, and it needs a tolerance range of 10 psi.