Too many type and assortment of dispenser are on service in china, the most popular and representative are consisted in two: first measuring transducer is leather cuff four-piston, equipped with gear pump, mechanical totalizer; the other is metal four-piston, equipped with lamina pump and mechanical totalizer.
7.1 Maintenance of flowmeter
7.1.1 Problems and relative solution to the four-piston flowmeter
7.1.1.1.Metal four piston flowmeter
7.1.1.1.1 Inaccuracy
After a while of utilization, due to the abrasion of internal components and the increasing delivery volume little by little, the indicative error will surpass the permissible error: +_0.3%:
7.1.1.1.1.1 Aperture of connection aggrandizement
The shafts of up and down joint move along the connection’s aperture when the flowmeter is on. The journey of piston and relatively the volume of delivery augment, when the aperture of shaft largens. The more the aperture of shaft largens, the more the delivered fuel.
Solution: replace another shaft
7.1.1.1.1.2 The gap between the copper jacket and large piston largens, the clearance between the small piston and copper jacket due to the frequent movement and friction as well as the low-precision and low-quality accessories, the clearance will easily formed. The fuel in the high-pressure cavities will be delivered from the clearance, which surpass the permissible error.
Solution: return it to the factory for repair or replacement.
7.1.1.1.1.3 Abate of the o gasket
There are four o gasket in both end of the up-down-shaft, four pistons are on two shaft, the clearance between the shaft and piston shall be sealed by the o gasket to avoid leakage. But abate happen when the machine run for a while.
Solution: dismantle four cover and four pistons, take out the shaft and replace the o gasket.
7.1.1.1.2 Off-work of the flowmeter (out of delivery or off work of transmission shaft)
Shed off the shaft of up-and-down perch
Shaft of bakelite wheel will shed off and fall into the jar easily. The loosening of each piston will made the transmission part of flowmeter locked and off work. dispenser will also stop.
Solution: relocate the perch of shaft, or stick with glue, or replace the bakelite wheel, or tighten the loosened piston
Some items lock the flow sensor
Broken spring, lamina, screw on the high-pressure valve of gas eliminator, gasket and others will prop up in the top of piston which will lock the piston and make the sensor unable to deliver fuel.
Solution: dismantle the piston, take out the jammed thing and repair the locked parts. |
