Overview
ISO 7113:1999 specifies requirements for single-piece metal cutting blades used on portable hand-held forestry machines - specifically brush cutters and brush saws. The third edition (1999) extends the scope to include circular saw blades and focuses on blade material quality, surface condition, marking, and basic dimensions and tolerances for saw-type blades. The standard replaces the second edition and transfers blade retention torque requirements to the relevant machine safety standard.
Key topics and technical requirements
- Blade surface quality
- Except for marking, blades must be free from surface imperfections deeper than 0.03 mm.
- Blade material and bend test
- Material must show no visible cracks after a specified bend test.
- Test specimen: cut with length perpendicular to material grain; specimen width (35 ± 5) mm and length at least 10 mm longer than 2H.
- Test conditions include an unlubricated specimen, V-block apparatus, ambient temperature 10 °C to 35 °C, and load application rate 1 mm/s to 10 mm/s.
- Dimensions and tolerances (saw blades only)
- Basic diameters, thicknesses, centre-hole sizes and run-out (total indicator reading) tolerances are specified (see standard table for exact values).
- Verification of run-out uses a washer and measuring setup as illustrated in the standard.
- Marking
- Blades must be durably marked with at least:
- Maximum allowed rotational speed (rpm)
- Rotational direction (when applicable)
- Manufacturer name or trademark
- Standards committee and scope change
- Prepared by ISO/TC 23/SC 17 (manually portable forest machinery). Retention torque requirement removed from this document and handled in the machine safety standard for brush cutters and grass trimmers.
Applications and who uses it
ISO 7113 is practical for:
- Blade manufacturers - to design, produce and QC single-piece metal blades and saw blades for brush cutters.
- Equipment OEMs and system integrators - to select compatible cutting attachments and ensure safe operating speeds and mounting.
- Test laboratories and quality inspectors - to perform bend tests, surface inspections and run-out verification.
- Procurement managers and safety officers - to specify compliant blades in purchasing documents and maintenance procedures.
- Service technicians and end users - to understand marking and maximum permitted rpm information for safe operation.
Related standards
- ISO 7112 - vocabulary for portable hand-held brush-cutters and grass-trimmers (referenced).
- Machine safety standard(s) for brush cutters and grass trimmers - now address blade retention torque and related machine-level safety requirements.
Keywords: ISO 7113, portable hand-held forestry machines, brush cutters, single-piece metal blades, saw blade dimensions, bend test, blade marking, run-out tolerance.
Open preview (PDF)Portable hand-held forestry machines — Cutting attachments for brush cutters — Single-piece metal blades
