Honeywell Enraf Operation Manual page 44

4-2
Calibration
withstand line pressure if the prover is not removed from the process
line. Temperatures, both ambient and fluid, should be stable during
the procedure.
4.2.1 Equipment
1. Static leak differential pressure creator assembly, included with prover.
2. Differential pressure gauge 0-69 kPa (10 psi) or greater with sufficient
static pressure specifications to be equal or greater than the current
prover pressure.
3. Plumbing and valve arrangement similar to that shown in Figure 4-1.
4.2.2 Static Leak Detection Procedure
1. Block all inlet and outlet ports on the prover (including drains).
2. Refer to Figure 4-1, 4-2 & 4-4 below and install the differential
pressure gauge (1) between the inlet and outlet ends of the prover.
3. Fill the prover with liquid and vent off all air from the system.
4. Determine there are not leaks from the prover ports.
5. If necessary, blind the inlet, outlet and drain lines with blind flanges.
6. Power up the proving computer and the Honeywell Enraf prover.
7. From the proving computer, initiate a proving run to pull the
piston upstream.
8. Remove the plug from the drive cover end panel.
9. Install the differential pressure creator (2) in the threaded hole provided
in the drive system end plate and hand tighten, refer to Figure 4-3.
10. Rotate the adjustment screw (3) Figure 4-4 clockwise to push the
plunger out to apply force to the piston shaft and create a differential
pressure between the inlet and the outlet of the prover. Rotate the
adjustment screw until a differential pressure of 6 psid has been
created. Pressurize the unit slowly and watch the pressure gauge.
In some cases it might happen that applied pressure of 6 psid will
be significantly lost in the first couple of minutes. The reason is
that the poppet valve will need short period of time to fully close
and stabilize.
Therefore, it is our recommendation to allow at least 5 minutes
between the applied pressure and actual data recording.
11. Look the prover over for any obvious external leaks.
12. Start observing the differential pressure gauge for a period of 20
minutes. If the pressure has not dropped by more than 25% of the
starting differential pressure, it may be assumed that there are no
piston seal leaks. If the pressure has dropped to lower levels, it should
SVP Controller Operation Manual Part No.: 44200004 - Revision 2