Cause of Failures

The operators, the machine, the material and the band saw blade must form a harmonised system. Here, the operator controls the machine and can impact significantly on the performance and sawing result. In this connection, it is important to know possible failure reasons and their causes to come up with effective countermeasures to remedy these. Wear, broken teeth, broken welds and bands.

Possible failure reasons

Heavy Wear
Cutting sequence
Cracked Weld
Bandbreakage
Chipping of Tooth

Heavy Wear

Cause	Remedy
Excessive cutting speed	Reduce the band speed, adjust the parameters -> ParaMaster^®
Insufficient cooling	Cooling positioned correctly, insufficient quantity
Sand-coated, scale-coated or extremely hard material surfaces and/or hard inclusion in the cutting material.	Adjust the parameters / band type -> ParaMaster^®, Clean and/or sand down the material surface in the cutting area if necessary
Wrong initial use.	Observe the break-in regulations -> Break-in

Cutting sequence

Cause	Remedy
Dulling of the band	Change the band
Band guides do not stop the band precisely in the cutting direction, the guide is slanted	Check the guide
The side guides are too loose	Set the mechanical band guides to a gap of 0.02-0.05mm. Hydraulic band guides: Check the clamping pressure.
The band guides are too far apart	Position the band guides as close as possible to the cutting material
Feed is too high	Adjustment of the feed -> ParaMaster^®
Band tension is too low	Check with the WIKUS band tension measuring device. If necessary, increase the band tension.
Chip brushes damage the tooth blades on one side	Punctual renewal and correct setting of the brushes.

Cracked Weld

Cause	Remedy
Incorrect production of the welding point	Weld the broken band again, do not dispose of!
Potentially a hidden machine error	Checking the guide elements and traversing wheels of the machine

Bandbreakage

Cause	Remedy
Guide rollers stand too closely and roll the band	Check the play of the guide rollers and correct, if necessary.
Guide elements are in the wrong position and are not aligned with the two machine impellers	Check and correct, if necessary
Guide elements (band edge/band backing) are worn	Check and replace, if necessary
Band saw blade runs too deeply within the guides	Steps must be taken to guarantee that all the teeth and 1-2 mm of the gullet protrude from the band guides.
Band tension is too high	Check with the WIKUS band tension measuring device. Reduce the band tension, if necessary. Recommended: 250 - 300 N/mm²
Impellers have surface errors	Repair or replace impellers
Conicity of the impellers exert uneven loads on the band saw blade	Repair or replace impellers
Impellers have poor bearings	Set the play of the impeller bearings or replace
The band saw blade backing starts at the collar of the impellers	Adjust the course of the band saw blade (impellers and band guides)
The impellers do not run truly	Repair or replace impellers

Chipping of Tooth

Cause	Remedy
Insufficient band speed	Adjustment of the cutting speed - ParaMaster^®
Excessive band feed	Adjustment of the feed - ParaMaster^®
Tooth pitch and material cross-section not harmonised	Check tooth pitch and use a band with suitable tooth - Band selector / ParaMaster^®
Cutting material is insufficiently clamped / affixed	Better fixation of the workpiece that is to be sawn, especially for layer or bundle cutting
Formation of built-up edges	Checking the cooling and the chip space brush
Hard inclusions in the cutting material	Arrange a metallographically investigation of the cutting material, if necessary. Adapt parameter

More practical tips

Factors that Influence the Blade-Life

Prolonging the life of a band saw blade can lead to enormous savings potential for a company because it means that tooling and administrative costs can be reduced significantly.