MILLWRIGHT LEVEL 3 UPDATED FINAL EXAM
QUESTIONS AND ANSWERS SURE A+
✔✔What are two methods to raise and lower a stop plate? - ✔✔Cylinder operated
pivoting stop plate
Airbag operated sliding stop plate
✔✔What are some commonly used overload devices used to prevent drive system
damage on roll conveyors? - ✔✔Shear pin
Torque limiting clutch
Ball and detent overload
Hydraulic relief valve limiter
A torque arm
An electric motor overload in the motor starter
A fluid coupling fusible plug
Loose belts that slip if overloading of the conveyor takes place
Zero speed switch at the tail end so that the driver stops if the conveyor jams
✔✔What are the two systems that pneumatic conveyors operate on? - ✔✔Negative
pressure and positive pressure systems
✔✔When are vacuum conveying systems primarily used? - ✔✔When material must be
conveyed from more than one location to a single location.
, ✔✔What type of compressors do you positive pressure systems require on a pneumatic
conveyor? - ✔✔Positive pressure systems that require air at a predetermined pressure
are usually supplied by positive displacement compressors. Low pressure systems can
use dynamic compressors.
✔✔What are low pressure pneumatic conveyor systems usually driven by and to what
pressures? - ✔✔Lobe or roots type blowers. The system is usually limited to about 12
psig.
✔✔What are medium pressure pneumatic conveyor systems usually driven by and to
what pressures? - ✔✔Rotary blowers or sliding vane compressors, depending on the
pressure required. Medium pressure conveyors generally operate with air pressures
ranging from 15 psig to 45 psig.
✔✔What are high-pressure pneumatic conveyor systems usually driven by and to what
pressures? - ✔✔High pressure systems are usually driven by plant air that has been
cleaned of oil and sent through a dryer to remove any moisture. High-pressure systems
operate up to 125 psig.
✔✔What is a rotary feeder used for? - ✔✔A rotary feeder is used to ensure material is
able to enter the airstream in the pneumatic conveyor.
✔✔What is a control gate in a pneumatic conveyor? - ✔✔They are a means of
controlling or directing material flow. Gates have one or more discharge spouts and may
be manually or remotely operated.
✔✔What is an isolation or blanking gate? - ✔✔They're used when work is to be
performed inside a hopper or silo. These gates must be locked or chained in the closed
position in order to prevent accidental flow of materials into the confined space.
✔✔What is an air lock? - ✔✔Air locks are another type of gate. Two or more gates are
used with a rotary feeder to prevent pressurization of the feed hopper.
✔✔What do angled rolls move material against? - ✔✔A guide
✔✔What must you never do when replacing shear pins? - ✔✔Replace with a bolt or a
pin of a different diameter.
✔✔Eccentric rolls must be ________ in order to operate properly. - ✔✔Timed
✔✔What is an air slide conveyor? - ✔✔A rectangular or square duct that is separated
into two sections along its length by a porous material. The upper section contains the
QUESTIONS AND ANSWERS SURE A+
✔✔What are two methods to raise and lower a stop plate? - ✔✔Cylinder operated
pivoting stop plate
Airbag operated sliding stop plate
✔✔What are some commonly used overload devices used to prevent drive system
damage on roll conveyors? - ✔✔Shear pin
Torque limiting clutch
Ball and detent overload
Hydraulic relief valve limiter
A torque arm
An electric motor overload in the motor starter
A fluid coupling fusible plug
Loose belts that slip if overloading of the conveyor takes place
Zero speed switch at the tail end so that the driver stops if the conveyor jams
✔✔What are the two systems that pneumatic conveyors operate on? - ✔✔Negative
pressure and positive pressure systems
✔✔When are vacuum conveying systems primarily used? - ✔✔When material must be
conveyed from more than one location to a single location.
, ✔✔What type of compressors do you positive pressure systems require on a pneumatic
conveyor? - ✔✔Positive pressure systems that require air at a predetermined pressure
are usually supplied by positive displacement compressors. Low pressure systems can
use dynamic compressors.
✔✔What are low pressure pneumatic conveyor systems usually driven by and to what
pressures? - ✔✔Lobe or roots type blowers. The system is usually limited to about 12
psig.
✔✔What are medium pressure pneumatic conveyor systems usually driven by and to
what pressures? - ✔✔Rotary blowers or sliding vane compressors, depending on the
pressure required. Medium pressure conveyors generally operate with air pressures
ranging from 15 psig to 45 psig.
✔✔What are high-pressure pneumatic conveyor systems usually driven by and to what
pressures? - ✔✔High pressure systems are usually driven by plant air that has been
cleaned of oil and sent through a dryer to remove any moisture. High-pressure systems
operate up to 125 psig.
✔✔What is a rotary feeder used for? - ✔✔A rotary feeder is used to ensure material is
able to enter the airstream in the pneumatic conveyor.
✔✔What is a control gate in a pneumatic conveyor? - ✔✔They are a means of
controlling or directing material flow. Gates have one or more discharge spouts and may
be manually or remotely operated.
✔✔What is an isolation or blanking gate? - ✔✔They're used when work is to be
performed inside a hopper or silo. These gates must be locked or chained in the closed
position in order to prevent accidental flow of materials into the confined space.
✔✔What is an air lock? - ✔✔Air locks are another type of gate. Two or more gates are
used with a rotary feeder to prevent pressurization of the feed hopper.
✔✔What do angled rolls move material against? - ✔✔A guide
✔✔What must you never do when replacing shear pins? - ✔✔Replace with a bolt or a
pin of a different diameter.
✔✔Eccentric rolls must be ________ in order to operate properly. - ✔✔Timed
✔✔What is an air slide conveyor? - ✔✔A rectangular or square duct that is separated
into two sections along its length by a porous material. The upper section contains the
