What is the usual cause of overheating in high speed, grease-lubricated antifriction bearing - Answer- Faulty mounting practices
How can too much wear in gears be reduced - Answer- Proper meshed
Why are timing belts made with teeth - Answer- Doesn't slip
The insert, or spider, used in flexible jaw couplings is meant to - Answer- Transmit torque and accept misalignment
Clutches on machinery provide for disengaging and may also - Answer- Interrupt the power supply
What determines the selection of gear reducer size - Answer- Torque and speed
why do metal parts seize when there is a lack of lubrication - Answer- Metal to metal contact. (lube protects the bearing against corrosion)
What causes lubrication oil to get milky - Answer- Mixing incompatible oils, contamination
Why are heavy oils used - Answer- To reduce the friction from heat and wear
What is viscosity? - Answer- The resistance of a liquid to flow
Which machine condition can be determined by using oil analysis? - Answer- Various types of wear and take corrective action before fails
Acids that form in lubricants affect performance are a result of - Answer- Oxygen from the air and high temperatures
Shutting fluid discharge of an air operated reciprocating pump will cause the pump to - Answer- Overstroke
What is the pressure on a fluid - Answer- Measurement of force per unit area on an object in the fluid
What can you use to meet peak hydraulic system demands - Answer- A variable displacement pump
Pressure in the hydraulic system can be controlled electrically by the use of - Answer- Metering the flow of fluid into or out Hydraulic valves are typically adjusted by - Answer- Flow control valve and adjustment the control
Hydraulic reservoir suction lines can be raised for what - Answer- Create enough vacuum
When air is compressed its temperature and....? - Answer- The pressure and temperature of the air increases
The speed of a piston is determined by - Answer- Crankshaft stoke and the engine RPM
Safe operating speed of an air motor is controlled by the - Answer- Air supply pressure
Air line filters and lubricators should be installed at - Answer- closer where it is going to be used
Solenoid valve fails to open, check what? - Answer- Normally closed (power to open)
Centrifugal pumps, cavitation can result in? - Answer- Pump performance deterioration, mechanical damage, noise and vibration
Compressor running too hot, due to what? or do what? - Answer- Build up internal moisture and condensation
A pilot flame detector can be what? - Answer- If flame is actually lit
Air cooled condensers generally have? - Answer- Fan, ambient air
Tool used to measure threads? - Answer- Screw gauge- thread gauge- pitch gauge
How to put a bearing onto a shaft - Answer- Press fit
Main purpose of a rectifier is to? - Answer- Convert AC to DC
Variable frequency drives? And controllers - Answer- A variable frequency drive control the speed of AC motor by varying the frequency
Regulation of a power supply refers to the ? - Answer- Output
Control systems have what four basic components? - Answer- Controller, Amplifier, Actuator, and feedback
This device does not require an analog input module on a PLC? - Answer- Thermocouple
Final element in a control loop is the? - Answer- Control valve