Ozone Aging Test Chamber for Rubber

What is the Ozone Aging Test Chamber for Rubber?

An ozone aging chamber generates a controlled ozone concentration and holds strained rubber specimens in the flow, producing cracks that reveal resistance to ozone attack. It is the specified method for outdoor and stressed rubber products.

Overview

Ozone is generated, most often by a mercury-free ultraviolet lamp or by silent electrical discharge, and its concentration is measured and held at the value required by the method, commonly 25, 50 or 100 parts per hundred million. Specimens are mounted in fixtures that apply a defined static elongation or a cyclic strain, and the chamber holds temperature and, where required, humidity constant while air moves through at a set rate. Crack initiation time, crack density and crack length are recorded by visual inspection at defined intervals, usually with a microscope or reference photographs. Stainless steel construction and adequate exhaust handling are needed because the gas is corrosive and toxic, and the ozone monitor must be calibrated before each campaign.

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?

• Ozone concentration control from 25 to 500 pphm
• Ultraviolet or silent discharge generator
• Calibrated ozone monitor with alarm
• Static and dynamic strain fixtures
• Temperature and humidity control
• Stainless steel chamber with exhaust handling

What are the technical specifications?

A typical ozone aging test chamber for rubber configuration offers ozone concentration of 25–500 pphm adjustable, concentration accuracy of ±10% of set value, temperature range of 20–60 °C, temperature accuracy of ±0.5 °C, static elongation of 5–50% typical, holder dependent and dynamic strain cycle of Programmable frequency and amplitude. 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 Ozone Aging Test Chamber for Rubber is used in ozone cracking resistance of outdoor rubber products, evaluation of antiozonant waxes and additives, seal and gasket qualification for stressed service and quality verification of weather-resistant compounds. 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 Ozone Aging Test Chamber for Rubber?

Specify an ozone chamber when the product is used outdoors under stress or where electrified equipment generates ozone, and when the applicable standard is ISO 1431-1 or ASTM D1149. Confirm the concentration range covers the method and that static and dynamic fixtures are available, since crack results depend strongly on how strain is applied.

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.