433A Conveyor Systems 4 — Questions and Answers
Question 1: What is a roller conveyor and what are its two main types?
- A conveyor that rolls material into shapes
- A conveyor using a series of rollers to transport items, available as gravity-powered (unpowered) or motor-driven (powered) types (Correct answer)
- A conveyor used only for round objects
- A belt conveyor with extra-large rollers
Correct answer: A conveyor using a series of rollers to transport items, available as gravity-powered (unpowered) or motor-driven (powered) types
A roller conveyor uses a series of cylindrical rollers mounted in a frame to transport items. Gravity roller conveyors use a slight decline and the item's weight for movement. Powered roller conveyors use chains, belts, or individual motors to drive the rollers for controlled transport.
Question 2: What is the main advantage of a pneumatic conveying system?
- It is the cheapest conveying method
- It can transport bulk materials through enclosed pipelines over long distances with flexible routing, dust containment, and minimal material degradation (Correct answer)
- It can handle the heaviest materials
- It requires no energy to operate
Correct answer: It can transport bulk materials through enclosed pipelines over long distances with flexible routing, dust containment, and minimal material degradation
Pneumatic conveying uses air pressure or vacuum to transport dry bulk materials through enclosed pipelines. Its advantages include completely enclosed (dust-free) operation, flexible routing (around obstacles, vertical runs), multiple pickup and discharge points, and suitability for fragile materials.
Question 3: When installing a new conveyor belt, what is the correct procedure for tracking the belt?
- Run the belt at full speed immediately
- Run the belt empty at slow speed, systematically adjusting idlers from the tail toward the head, making small adjustments and allowing the belt to respond before making additional changes (Correct answer)
- Track the belt while it is stopped
- Adjust all idlers at once
Correct answer: Run the belt empty at slow speed, systematically adjusting idlers from the tail toward the head, making small adjustments and allowing the belt to respond before making additional changes
Belt tracking is performed with the belt running empty at reduced speed. Starting at the tail end, each idler is adjusted slightly, with time allowed for the belt to respond before the next adjustment. The process works systematically toward the head end, with only small adjustments at each step.
Question 4: What is the purpose of a plough (V-plow) on a belt conveyor?
- To plough snow off the conveyor
- To divert material off the side of the belt at an intermediate discharge point before the head pulley (Correct answer)
- To remove wrinkles from the belt
- To increase belt speed
Correct answer: To divert material off the side of the belt at an intermediate discharge point before the head pulley
A V-plow or diverter plow is a V-shaped blade that can be lowered onto the moving belt to divert material off one or both sides at intermediate points along the conveyor, allowing discharge before the head pulley.
Question 5: What safety device prevents personnel from being caught in conveyor nip points?
- Warning labels only
- Guards covering all nip points where the belt meets pulleys and where rotating parts could catch clothing or body parts (Correct answer)
- Speed reducers
- Louder operation for audible warning
Correct answer: Guards covering all nip points where the belt meets pulleys and where rotating parts could catch clothing or body parts
Nip point guards are physical barriers (mesh, plate, or shaped guards) installed at all points where the belt contacts pulleys, where rollers meet the belt, and around other rotating components. They physically prevent hands, clothing, or body parts from being drawn into the pinch point.
Question 6: What is the function of a belt tripper on a conveyor?
- A device that trips (stops) the belt in an emergency
- A traveling discharge device that lifts the belt over a raised pulley to discharge material at any point along the conveyor length (Correct answer)
- A device that trips when the belt breaks
- A circuit breaker for the conveyor motor
Correct answer: A traveling discharge device that lifts the belt over a raised pulley to discharge material at any point along the conveyor length
A belt tripper is a movable structure with a raised pulley assembly that lifts the belt to create a discharge point. The tripper can travel along the conveyor length on rails, allowing material to be deposited at different locations, such as filling storage bins in sequence.
433A Conveyor Systems 4
What is a roller conveyor and what are its two main types?