Overview
ISO/TS 19858:2024 - "Forestry machines - Portable chain-saws - Test method for evaluating saw chain lubricity" defines a laboratory test method to classify the lubrication ability of saw chain lubricants when used with a guide bar and saw chain. The Technical Specification reproduces stress conditions experienced during sawing to assess lubricant performance in reducing friction and wear between chain and guide bar. The procedure is intended for reproducible comparison of lubricants and for inclusion of lubricant recommendations in manufacturers’ documentation.
Key Topics and Requirements
- Test rig and components
- Loading wheel diameter: 185 ± 3 mm
- Oil pump precision: ±0.1 ml/min
- Cutting attachment: guide bar 400 ± 10 mm length, pitch 9.525 mm (0.375"), groove width 1.3 mm, bar nose radius 32 ± 1 mm
- Chain: 60 drive links, pitch 9.525 mm, chain without teeth and bumpers
- Environmental condition
- Ambient temperature: 20 ± 5 °C
- Test sequence and parameters
- Run-in: 10 min
- Long duration: 180 min
- Chain preload: 20 N
- Contact load: 80 ± 5 N
- Lubricant flow: 50 ± 5 ml/min
- Chain speed: 2 ± 0.2 m/s
- Temperature sampling rate: minimum 6 readings per minute
- Measurements
- Chain elongation measured on three non-overlapping sectors (minimum 26 rivets per sector); tension during measurement: 50 ± 2 N
- Guide bar wear measured with dial indicator ±0.01 mm using a 4 mm ball head to quantify depth loss
- Surface temperature measured at a defined point with thermometer accuracy ±3 °C
- Clean guide bar and chain with ultrasonic cleaner before testing and before measurements
- Guidance values (for comparison, not mandatory pass/fail)
- Overall chain elongation: **