ISO 6803:2017

Overview

ISO 6803:2017 specifies a standardized procedure for hydraulic-pressure impulse testing without flexing of rubber or plastics hoses and hose assemblies. It covers both high-pressure testing (greater than 3 MPa) and low-pressure testing (1.5 MPa to 3 MPa) for assemblies that experience pulsating hydraulic pressures in service. The method verifies endurance under repeated pressure pulses and is intended for inclusion in product requirements and acceptance testing.

Key topics and technical requirements

• Scope: Impulse testing without flexing; flexing tests are covered by ISO 6802.
• Pressure ranges: High > 3 MPa; Low 1.5–3.0 MPa.
• Pulse frequency:
  • High-pressure: 0.5 Hz to 1.3 Hz
  • Low-pressure: 0.2 Hz to 1.0 Hz
• Pressure waveform control: Pulse waveform must lie within prescribed envelope (figures in the standard). The nominal rate of pressure rise is defined (parameter k = 5 MPa) and the actual rate must be within ±10% of the nominal.
• Apparatus and instrumentation:
  • Pressure-application system that circulates hydraulic fluid at the specified temperature.
  • Recorder/oscilloscope with natural frequency > 250 Hz, critically damped, and flat response to within 5% up to 0.6×natural frequency.
• Test fluid: Preferably ISO VG 32–100 (kinematic viscosity 32–100 mm2/s at 40 °C); other fluids by agreement.
• Test temperature: Normally specified by the referring hose standard; preferred temperatures include 85, 100, 120, 125, 135, and 150 °C. Fluid circulation tolerance ±3 °C.
• Test pieces: Complete hose assemblies with fittings attached (normally four unaged assemblies unless otherwise specified). Hose bend configuration: 180° for nominal ID ≤ 22 mm; 90° for > 22 mm.
• Result reporting: Number of cycles to failure or cycles completed; full test conditions and fitting details must be recorded. Leakage classification per ISO/TR 11340.
• Optional cool-down leakage test: Procedure included for checking leakage during cool-down at specified cycle percentages and final observation over 1 000 cycles.
• Destructive: The impulse test is destructive-tested assemblies should be discarded.

Applications and users

Who uses ISO 6803:2017:

• Hose and hose-assembly manufacturers (product validation, R&D)
• Independent test laboratories and quality assurance teams
• OEMs and procurement/specification engineers for hydraulic systems
• Regulatory and certification bodies for component acceptance

Practical uses:

• Endurance/acceptance testing of hydraulic hoses used in mobile equipment, industrial machinery, and high-pressure systems
• Comparative testing of hose/fitting combinations and failure analysis
• Specifying performance requirements in product standards and contracts

Related standards

• ISO 6802 - Hydraulic impulse test with flexing
• ISO 3448 - ISO viscosity classification (for test fluid selection)
• ISO 8330 - Vocabulary for rubber and plastics hoses and assemblies
• ISO/TR 11340 - External leakage classification for hydraulic systems

Keywords: ISO 6803:2017, hydraulic-pressure impulse test, rubber hoses, plastics hoses, hose assemblies, high-pressure testing, low-pressure testing, impulse testing without flexing, hose test procedure.