Saw Blade Change, Sharpening and Tensioning Procedure

Purpose. This procedure describes how circular and band saw blades are removed, inspected, sharpened, tipped, levelled, tensioned and refitted so that sawing accuracy and recovery are maintained and no one is injured during a blade change.

1.Scope

This procedure applies to every saw blade and cutter head in the green mill, dry mill and moulder at Heyfield, and to saw shop work for external customers.

2.Isolation before a blade change

The machine must be stopped, isolated at the main isolator, locked out with the operator's personal lock and tested for zero energy before any guard is opened. Blade changes on the band mill require two people. The saw technician must confirm with the line operator that the machine is released before and after the change.

3.Removing and inspecting the blade

Blades must be handled with cut-resistant gloves and lifted with the blade cart or crane, never carried by hand where the blade is over the weight limit on the shop sign. Each blade must be inspected for cracks, missing tips, gullet damage and heat marks and the findings recorded on the blade history card in the saw shop work order system.

4.Sharpening and tipping

Circular blades must be sharpened on the grinder with the hook, clearance and top bevel angles set for the blade type and timber species. Missing or worn tungsten and Stellite tips must be replaced and ground to the pattern. Grinding must be done with coolant flowing and with the grinder guard closed.

5.Levelling and tensioning

Circular blades must be checked for flatness on the levelling bench and tensioned with the roller or hammer to the tension gauge reading for the blade diameter and speed. Band saw blades must be checked for level, tension and back crown on the bench and swaged and shaped where the tooth profile requires it. Blades outside tolerance must be tagged out and not refitted.

• Check flatness with the straight edge and feeler gauge
• Roll from the centre outward to the tension line
• Record the tension gauge reading on the history card
• Tag blades that cannot be corrected

6.Refitting and alignment

The refitted blade must be clean, torqued to the machine setting and aligned with the guides and fence. The saw technician must run the first cut with the operator and check sawing deviation with the gauge before the machine is returned to production.

7.Records

Every blade change, sharpen and inspection must be recorded as a completed work order with the blade identifier, work done, gauge readings and technician. Blade histories will be reviewed monthly to identify blades approaching the end of their life.