Overview
ISO 8947:1993 - "Agricultural machinery - Equipment for working the soil - S-tines: test method" specifies reproducible mechanical tests for S-type cultivator tines (S-tines). The standard defines procedures to compare quality and performance of S-tines through dimensional checks, static bending, lateral bending, variation in working depth and soil penetration angle, permanent deformation, and fatigue testing. Tests apply to S‑tines as defined in ISO 5678 and can be used for similar products.
Key Topics and Requirements
- Scope and samples
- Applies to S-tines (see ISO 5678). Minimum sample size: not less than 20 tines of the same type/manufacturer; results reported as averages (three tines per reported result).
- Dimensional check
- Verify five tines against the main dimensions and fixing clearances of ISO 5678 and ISO 5680; report any deviations.
- Bending in direction of travel
- Static horizontal loads applied at the shovel lower fixing hole; load series provided (50–1 000 N). Measure deflection a at centre of the shovel lower fixing hole for each loading.
- Lateral bending
- Static loads perpendicular to the tine at the shovel lower fixing hole; load series provided (50–600 N). Measure lateral deflection b for each loading.
- Variation in working depth and soil penetration angle
- Performed with the standard shovels that accompany the tine. Measure change in working depth C and change in penetration angle α under loads up to 1 000 N.
- Permanent deformation
- Apply higher static loads (500–5 000 N per the standard), then release and record permanent set d.
- Fatigue test
- Sinusoidal loading at 6 Hz with a specified stroke (initial bending at 1 000 N plus a pretension). The standard defines the required number of cycles; a tine surviving the test is regarded as unbreakable.
- Reporting
- Annex A provides a normative example test report format including tables for all measured data.
Practical Applications and Users
- Manufacturers use ISO 8947 for product design validation, quality control, and material selection.
- Test laboratories adopt the method for independent performance certification and comparative testing.
- Procurement and OEMs reference the standard in technical specifications to ensure consistent performance of cultivator tines.
- R&D and durability engineers use the fatigue and deformation data to improve tine geometry and metallurgy.
- Regulatory bodies and certification agencies rely on standardized test methods for conformity assessment.
Related Standards
- ISO 5678:1993 - S‑tines: main dimensions and clearance zones
- ISO 5680:1979 - Tines and shovels for cultivators: main fixing dimensions
Keywords: ISO 8947, S-tines test method, agricultural machinery, cultivator tines, bending test, fatigue test, permanent deformation, working depth, soil penetration angle, ISO 5678, ISO 5680.