Oxygen Pressure Aging Tester for Rubber

What is the Oxygen Pressure Aging Tester for Rubber?

An oxygen pressure aging tester exposes rubber specimens to oxygen at elevated pressure and temperature in a sealed vessel, accelerating oxidative degradation far beyond air oven conditions. It is used for rapid screening of antioxidant systems and for specification methods requiring it.

Overview

Specimens are placed in a steel pressure vessel that is purged and filled with oxygen to a defined pressure, typically about 2.1 MPa, and held at a set temperature, often 70 °C, for a defined time. The combination of elevated oxygen pressure and temperature greatly increases the oxidation rate, so measurable property change occurs within days, and the severity can be varied by adjusting pressure, temperature or duration. After depressurisation the specimens are conditioned and their tensile strength, elongation or hardness compared with control specimens from the same lot. Because the vessel is a pressure system, it must be manufactured and inspected to the applicable pressure equipment requirements, with relief devices, an interlock preventing opening under pressure and a record of the pressure and temperature profile of each run.

How does it work?

Accelerated ageing raises one or more degradation factors above service conditions so that measurable change occurs within days rather than years. In a hot air oven the dominant factors are temperature and oxygen, and the test specifies temperature, air exchange rate and duration under the standard method; specimens are then conditioned and their tensile strength, elongation or hardness compared with the unaged values. Ozone chambers generate a controlled ozone concentration and apply static or dynamic strain, because ozone cracking occurs only in strained rubber. Xenon arc chambers reproduce the ultraviolet and visible spectrum of daylight with controlled irradiance, temperature and humidity so that weathering effects on appearance and mechanical properties can be assessed. Oxygen pressure tests place specimens in oxygen at elevated pressure and temperature, which accelerates oxidative degradation far beyond what an air oven achieves.

What are the key features?

• Pressure vessel rated to about 2.5 MPa
• Oxygen supply with purge and fill sequence
• Temperature control to 100 °C
• Pressure and temperature logging per run
• Safety relief valve and door interlock
• Specimen racks for multiple test pieces

What are the technical specifications?

A typical oxygen pressure aging tester for rubber configuration offers working pressure of About 2.1 MPa (300 psi), vessel rating of 2.5 MPa design pressure, temperature range of Ambient to 100 °C, temperature accuracy of ±1 °C, gas of Oxygen, ≥ 99.5% and vessel volume of 5–20 L. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Oxygen Pressure Aging Tester for Rubber is used in rapid antioxidant screening in compound development, specification methods requiring oxygen pressure ageing, cable and hose compound oxidative stability and comparison of stabiliser packages. Across the wider Aging Ovens class, laboratories also deploy it for heat resistance verification of vulcanised rubber, antioxidant and stabiliser system screening and ozone cracking resistance of strained rubber.

Which standards and certifications apply?

Relevant standards and methods include ISO 188, ISO 1431-1, ISO 4892-2, ASTM D573, ASTM D572, ASTM D1149, ASTM G155 and IEC 61010-1. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Compliance with an aging method depends on the exact conditions, so verify temperature uniformity and airflow with a calibrated recorder, and confirm the air exchange rate of the oven rather than assuming it from the fan setting. Load only the number of specimens the standard allows, since overcrowding reduces airflow and changes results. Record aging time, temperature and atmosphere with each batch, condition specimens after aging and compare them with a control from the same production lot. Ozone and xenon chambers need their sensors and lamps calibrated and replaced on schedule, and oxygen pressure vessels must be inspected and pressure-tested as required by local rules for pressurized equipment.

How do I select the right Oxygen Pressure Aging Tester for Rubber?

Specify an oxygen pressure tester when a standard method calls for it or when a much faster indication of oxidative stability than an air oven can provide is needed for formulation screening. Confirm the vessel rating and safety devices, the gas supply arrangement and the logging capability, and check the specimen capacity against the number of tensile tests you plan to run.

How does it compare with other Aging Ovens variants?

Select the degradation factor that matches the service environment. Heat resistance for engine, hose and belting compounds is tested in air ovens, with forced-air circulation used when temperature uniformity across many specimens matters. Where outdoor exposure involves sunlight, a xenon arc chamber with humidity control is appropriate, and where ozone from electrical equipment or urban air is the concern, a dedicated ozone chamber with strain fixtures is required. Oxygen pressure testing is chosen for rapid screening of antioxidant systems and for specification methods that call for it. Whichever method is used, specify chamber capacity, temperature uniformity, the control ranges for the degrading factor and the specimen holders, and ensure the instrument can reproduce the exact conditions named in the standard.