Overview
ISO 6194-4:2009 - "Rotary shaft lip-type seals incorporating elastomeric sealing elements - Part 4: Performance test procedures" specifies general test methods for qualifying rotary shaft lip-type seals that use elastomeric sealing elements. These seals are intended for low-pressure applications. The standard defines dynamic and low-temperature performance tests, material-property tests for elastomers, pre-test requirements, recording and acceptance criteria, and typical test-report formats.
Key topics and technical requirements
- Scope and purpose: Test procedures for qualification of rotary shaft lip-type seals with elastomeric elements; complementary to ISO 16589 (thermoplastic sealing elements).
- Pre-test checks: Verification of seal conformity to drawings/specification and supplier-provided elastomer batch data (density, hardness, maximum compression set, max volume change after fluid immersion, low-temperature modulus where applicable).
- Dynamic normal-temperature test:
- Test apparatus requirements: rotating shaft and housing able to reproduce specified eccentricity/off‑set, maintain shaft speed within ±3% and eccentricity within ±0.03 mm, and maintain test fluid temperature within ±3 °C.
- Test fluid volume minimum (750 cm³) and fluid level (0.3D–0.5D above lowest shaft point).
- Typical sample regime: six seals, 10 cycles of 24 h each (14 h at normal operating temp/speed, 6 h at maximum envisaged temp/speed, then 4 h shutdown).
- Means to collect and measure leakage and to pressurize the housing.
- Dynamic low-temperature test: apparatus, installation and reporting tailored to assess seal performance and stiffness under low-temperature conditions.
- Material testing of elastomeric components: includes density, hardness (ISO 48), compression set (ISO 815-1/2), fluid immersion effects (ISO 1817), dry-heat ageing (ISO 188), low-temperature brittleness/stiffness (ISO 812) and recording requirements.
- Test reporting: Annexes provide typical examples of dynamic and material test reports; identification statements and acceptance criteria are defined.
Applications and users
ISO 6194-4:2009 is used by:
- Seal manufacturers for product qualification and material batch verification.
- Independent test laboratories performing performance and endurance testing.
- Design and QA engineers in automotive, industrial machinery, pumps, gearboxes and other equipment with rotating shafts operating under low pressure.
- Purchasers and specification writers who require standardized test evidence for procurement.
Practical benefits include repeatable performance validation, material traceability, and consistent acceptance criteria that reduce field failures and support product development.
Related standards
- ISO 6194 series (Parts 1–5) - dimensions, vocabulary, storage/install, performance tests, visual imperfections
- ISO 16589 - seals with thermoplastic sealing elements (complementary)
- Referenced test methods: ISO 48, ISO 188, ISO 812, ISO 815-1/2, ISO 1817, ISO 2781, ISO 5598
Keywords: ISO 6194-4:2009, rotary shaft lip-type seals, elastomeric sealing elements, performance test procedures, dynamic test, low-temperature test, seal qualification, material testing, fluid power systems.