433A Conveyor Systems 3

Question 1

What is the function of a backstop on an inclined belt conveyor?

Accepted Answer

To prevent the loaded belt from running backward if the drive loses power, which could cause material runback and drive damage

Answer

A backstop (holdback) is a one-way clutch or brake on the drive shaft that allows rotation in the forward direction but locks against reverse rotation. On inclined conveyors, it prevents the loaded belt from running backward if the motor stops or loses power.

Question 2

What is a vibrating conveyor and what type of material does it handle best?

Accepted Answer

A conveyor that moves material along a trough using controlled vibration, ideal for hot, abrasive, or screening applications

Answer

A vibrating conveyor uses an oscillating trough driven by an eccentric or electromagnetic vibrator to move material in short, repeated tosses. It is excellent for handling hot materials, performing screening operations, and conveying abrasive products that would damage belts.

Question 3

What is the correct method for belt splicing using a vulcanized splice?

Accepted Answer

Strip back the belt cover and fabric plies, assemble stepped or finger joints with bonding cement, then cure under heat and pressure in a vulcanizing press

Answer

A vulcanized splice involves carefully stripping back the belt covers and fabric plies to create stepped or finger joints, applying bonding cement and uncured rubber between layers, then curing the assembly under controlled heat and pressure in a vulcanizing press to create a permanent, strong joint.

Question 4

What is the purpose of return idlers on a belt conveyor?

Accepted Answer

To support the empty belt on its return run back to the tail pulley, preventing excessive sag and belt damage

Answer

Return idlers support the belt on the lower (return) strand as it travels back to the tail pulley after discharging material. They prevent excessive belt sag, reduce belt flapping and wear, and are typically spaced farther apart than carrying idlers since the belt is unloaded.

Question 5

What is a drag chain conveyor (en-masse conveyor) used for?

Accepted Answer

Moving bulk material through an enclosed housing using a chain with flights that drag material along the bottom of the trough

Answer

A drag chain (en-masse) conveyor uses a single or double chain with attached flights (crossbars) inside an enclosed trough. The flights drag bulk material along the bottom of the trough. The enclosed design contains dust and handles multiple discharge points.

Red Seal Millwright 433A Practice Test

Red Seal Millwright 433A Practice Test

433A Conveyor Systems 3