Spencer Vacuum Cleaning Systems - Manual (Page 18)

18
Trouble Probable Cause Corrective Action
Insufficient air Low vacuum as determined by measurement with a manometer or vacuum gauge:
through system – Incorrect rotation. Change motor leads to correct rotation.
– Customer has reassembled machine incorrectly. Refer to instructions in this book and to assembly print;
disassemble machine and reassemble properly.
– Machine sized for requirements given, but air lines Increase line sizes or install machine providing higher
too small causing excessive frictional loss. vacuum.
– Valves in line, causing excessive losses. Install larger valves or install machine providing higher
vacuum.
– Inlet or outlet partially blocked, i.e., blast gate shaft Check blast gate; remove and repair if necessary.
slipped in handle and shutter does not open fully.
– High inlet temperature, i.e., higher than designed inlet Direct inlet line to cooler area; replace machine with
temperature. one designed for correct temperature.
– Lower inlet pressure, i.e., lower than designed inlet Remove inlet restrictions or install machine providing
pressure. higher vacuum.
– Machine not running at designed speed. Refer to motor manufacturer’s instructions; check
motor speed; check voltage connections.
– Machine air passages clogged with material. Disassemble, clean and inspect all parts.
– Impellers worn out due to explosion, abrasion, or vibration. Replace Impellers.
– Inlet spiral has rotated partially blocking inlet (4-bearing Rotate spiral to correct position and pin or clamp in
outboard machines only). position.
Machine design capacity too small for the system:
– System requirements incorrectly calculated by customer. Install larger volume or higher vacuum machine to
handle correct system requirements.
– Too many leaks and/or openings. Locate and repair all leaks.
Measuring gas or air flow incorrectly:
– Flowmeters incorrectly calibrated. Calibrate flowmeters; be certain proper orifice is used
for meter (check with flowmeter manufacturer).
– No means of measurement available so customer is Obtain and install flowmeter.
guessing at airflow.
Machine noisy External machine malfunction – bearing whining or growling:
– Too much grease – bearing hot. Remove excess grease. Check bearing temperature
(refer to lubrication instructions in this manual).
– Too little grease – bearings dry. Grease according to instructions.
– Bearing(s) failure. Replace bearing(s).
– Bearing retainers worn. Replace bearing(s).
– Bearings turning on shaft – retaining nut loose. Tighten nut, check for damage.
– Bearing turning in housing – housing worn. Replace housing and bearing.
– Bearings replaced incorrectly – particularly in tandem Install bearings correctly according to instructions:
assembly, i.e., angled, cramped or put in backwards. check bearing, shaft and housing dimensions.
– Bearing(s) overloaded – too much thrust due to higher Replace bearing(s). Reduce thrust by lowering gas or air
density gas or air than designed for. density, installing smaller Impellers, or installing
machine designed to proper conditions.
Internal machine malfunction:
– Impeller(s) hitting after customer reassembly and/or Reassemble according to instructions, tighten
Impeller(s) slipping shaft due to heat or excessive inlet Impellers. Bleed air at low flow to reduce heat. Change
pressure. inlet conditions if necessary.
– Impeller(s) coming apart due to age or wear from dirty air. Replace Impeller(s).
– Deflector coming apart due to age or wear from dirty air. Repair or replace deflector.
– Machine operating in surge or unbalanced flow range. Increase air flow to stop surge condition.
– Keyed hubs rattle on start up. Normal. These will be loose when machine is cold –
they will tighten as machine reaches operating
temperature.
– Machine out of balance running rough. Rebalance and/or clean machine (See next problem –
“Machine Vibrating”).
– Deflector packings rubbing on shaft or Impeller hub Ignore if audible only when machine turned by hand.
(will seat themselves if new). If otherwise audible, replace packings.
– Motor not aligned in casing (Standard Overhung) causing Reassemble and carefully align shaft and motor properly.
Impeller to hit.
– Four-bearing machines – coupling misaligned and/or dry Check alignment; check coupling for wear and replace if
of grease. necessary. Relubricate according to instructions.
– Foreign material in machine. Disassemble machine, inspect and clean. Reassemble
and, if necessary, install filter to prevent further clogging.
Refer to Separator sections.
XIV. Trouble Shooting Guide