Screw Conveyors common Failitures & Solutions

Screw Conveyor Troubleshooting Guide

The problems or failures in the screw conveyors are mainly due to the wear of the components during the working hours, we list below the main problems that arise and a quick guide to efficiently detect and solve the problem, some of them are refer to corrective maintenance.

Urgent maintenance indicators on screw conveyors

The screw conveyor has a service life of 5-10 years. The life of the screw conveyor depends on the abrasiveness of the bulk material being handled and the amount of use. It is advisable to lift the conveyor cover periodically (making sure the power supply is locked out before opening the cover) and check the screw conveyor for cracks, any reduction in outside diameter, bent or deformed screw, or material build-up.

Another indicator of a need for maintenance is an overload in the amperage at the start of the motor, or an overload switch that unexpectedly "trips".

Replacement times may vary depending on the parts of the screw conveyor, as the bearings require replacement relatively quickly and replacing the screw conveyor takes much longer. It may be wise to have a few replacement parts to keep your screw conveyor running in tip-top condition.

Failiture

Probable Cause / Corrective Action

Premature trough failure

Trough gauge (thickness) is too thin / Increase thickness. Consult a Bega consultant for material recommendations

Screw Coveyor Deflection / Eliminate excessive deflection. Consult a Bega advisor for tubular shaft diameter and schedule recommendations.

Screw Conveyor Deflexionado / Enderece o Reemplace. Revise antes de operar.

Accelerated wear of the Auger Flight

Gauge (thickness) too thin / Increase thickness. Consider a harfaced flight or use abrasion resistant materials.

RPM too high / Lower conveyor speed. Consult a Bega advisor to determine the appropriate load for your material type.

Intermediate shaft rupture

Insufficient torque capacity / Increase torque capacity or use a larger diameter shaft. Check your motor's amperage demand for torque requirements.

Incorrect alignment / Re-align trough parts and pendants correctly, according to installation instructions.

Excessive shaft wear / Replace intermediate shaft.

Shaft bore oblongation

Insufficient number of screws / Increase the number of screws.

Screw conveyor subject to a series of sudden changes of direction or frequent stops / starts or frequent overloads / Stop frequent stops / starts or overloads. If possible increase the bearing capacity of the shaft, and / or increase the number of screws.

Drive shaft break

Insufficient torque capacity / Increase torque capacity.

Obstruction inside screw conveyor / Check screw conveyor alignment.

Motor Overload / Protection Relay

Motor draws too much amperage / Recheck HP calculations. Check the characteristics of the material handled, check the capacity, regulate the feeding.

Bearing or pillow block failure in feed-side end cap

Material enters bearing / Add or improve seal. Replace with an outboard bearing. Place auger flight to center of discharge.

Hanging bearing failure

Incorrect alignment / Realign trough and hangers.

Heat due to high temperature of the conveyed material / Use a suitable bearing or bushing material for the application.

Heat due to insufficient lubrication / Lubricate properly.

Thrust due to tube pressing on bearing bushing / Check coupling bolts and holes for elongation and wear. Replace as necessary to achieve proper clearances between components.

Unsuitable material for the bearing or bushing / Consult your Bega advisor who will recommend the type of bushing you require based on the characteristics of the material to be transported.

Inadequate speed / Consult your Bega advisor who will recommend the appropriate speed based on the material to be transported.

Inadequate load in the trough / Consult your Bega advisor who will recommend the appropriate load based on the material to be transported.

Typical Screw Conveyor Wear Parts

Screw conveyors are available in shaft and shaftless configurations. The type of screw conveyor that is best for your application is determined by the needs of your specific process. For this article, we will focus on the shaft screw conveyor style and typical shaft screw conveyor wear parts.

A screw conveyor with shaft is a piece of equipment that has a solid or tubular shaft that crosses the length of the tundish and the screw conveyors go inside. The solid or tubular shaft supports the auger flights to prevent them from being in contact with the trough. The benefits of a shaft conveyor are that they can be longer, there is no need for a liner on the bottom of the channel or tundish and associated maintenance, and they can operate at higher RPM since there is no concern about liner wear.

The shaft screw conveyor is generally considered low maintenance. However, there are some common "wear components" that may need regular or intermittent attention. Generally, the best wear indicator and parts to replace are a good visual examination of the equipment and listening carefully for any unusual sounding noises.

Typical Shaft Screw Conveyor Wear Parts

Bearings.
Suspension bearings or hanging bearings.

The bearings of the shaft screw conveyor must be monitored for wear. These are located on the outside of the equipment at the ends of the material loading and unloading unit. Bearings should be checked for good lubrication. They have a long life, but they are one of the first items that may need replacement. Indicators for this are visual and audible.

Screw conveyors have a suspension bracket every 120 "or every 3 meters. It is important to lift the conveyor cover and check the suspension bearings for wear and alignment. Before lifting the cover, always block the feed of the conveyor. the unit. Hanging bushings or bearings are manufactured from UHMW-PE or hardened iron. Each may show long-term wear and may need replacement. Suspension bearing replacement is when wear exceeds 1/8 ".