High Efficiency Arc Gear Oil Transfer Pump YHCB Series For Tank Truck

Failure phenomenon

(a) Pump not primed.
(b) Suction lift too high. Check with a gauge at the pump suction
(c) Wrong direction of rotation
(d) Pump not rotating (failure of drive from prime mover)
(e) Suction & Delivery pipes connected on wrong sides of pump

(a) Air leaks in suction or through stuffing box
(b) Speed too low
(c) Suction lift too high, or not enough suction head (for hot liquids)
(d) Foot valve too small or obstructed
(e) Foot valve or end of suction pipe not immersed deeply enough
(f) Piping improperly installed permitting air or gas to pocket in pump
(g) Mechanical defects: Pump damaged, Pump badly worn
Packing defective
(h) Relief valve not seating or jammed by foreign matter.
(i) Relief valve set for too low a pressure.

(a) Leaky suction lines
(b) Suction lift too high
(c) Air or gases in the liquid

(a) Speed too high
(b) Liquid heavier or more viscous than we quoted for
(c) Suction or discharge line obstructed
(d) Mechanical defects Shaft bent Rotating element binds
Stuffing boxes too tight Misalignment due to improper connection of pipe lines or driver
(g) Check pressure is being measured at the pump and not some distance away from the pump thus ignoring pressure losses in piping, valves, etc.
(h) Discharge pressure higher than quoted for.

(a) Speed too high
(b) Suction lift or viscosity too high (piping diameter too small) preventing filling of gear tooth spaces
(c) Wrong direction of rotation (Note: recesses in the pump covers to prevent hydraulic noise operate only in one direction)
(d) Badly supported pipes or bed-plates causing resonant vibration. Rubber mounting can help.
(e) Relief valve chattering
(f) Pressure too low: an increase in pressure can prevent gear noise in low pressure applications
(g) Worn pump, check for wear

(a) Packing hard and shafts scored
(b) Pressure on pump too high or pressure relief passage blocked
(c) Shaft run out excessive
(d) When repacking a gland all the old packing must be removed. It is not good enough just to add extra rings as the original packing becomes compressed

(a) Abrasive liquid / Contaminated liquid
(b) Excessive speed
(c) Misalignment
(d) Excessive loading on drive shaft, axial or radial
(e) Pump is running dry
(f) Viscosity less than stated

(a) Back pressure too great
(b) Incorrect supply voltage
(c) Motor phasing
(d) Pump operating outside temperature range
(e) Air temperature too high
(f) Motor covered in dust
(g) Electrical connections not correct for starting method
(h) Natural ventilation blocked

(a) Re-circulating small amount of liquid
(b) Over tight gland
(c) Running dry
(d) Pump out of alignment