Evaluating Piston-Cylinder Cleanliness
Scope: Applicable to 10 kPa/kg piston-cylinders
The piston-cylinder must be performance tested before fully reassembling the PG7601 System – ie: putting the mass set and the AMH-38 back on. After the piston-cylinder module is reassembled, it must spin for 60 seconds without assistance. This is a Go / No-go test. A stop watch is required for the test.
The article is written for systems with an AMH-38 but it can be used for manual mass set systems. The test should be performed with a minimum mass condition which for a manual mass system is the mass of the piston and the mass carrying bell -- approximately 0.8 kg.
- Install the P-C module into the mounting post.
- Place the spindle on top of the piston cap, and slide the mass bell down over the assembly.
- Use the manual “up / down” control buttons on the pressure controller (ie: PPC3 or PPC4) front panel to manually float the piston. This test is performed with only the mass of the piston, the cap, the spindle, and the mass bell.
- Press the [SYSTEM] button on the PG7000 Terminal to view the rotation speed.
- Manually spin the piston to just beyond 100 rpm - use a gloved hand to spin it.
- Begin timing when the speed drops to 100 rpm. Continue to time until the piston rotation comes to a complete stop.
PASS = 60 seconds or more to spin from 100 to 0 rpm
FAIL = less than 60 seconds.
If the piston fails to spin for longer than 60 seconds, then it is not sufficiently cleaned.