PID Controlled UV Aging Test Chamber / Programmable UV Environment
Testing Equipment
1. Application
Ultraviolet aging test chamber uses ultraviolet lamp as light
source. By simulating the ultraviolet radiation and condensation in
natural sunlight, accelerated weatherability test of materials is
carried out to obtain the results of weatherability of materials.
It can simulate the environmental conditions such as ultraviolet,
rain, high temperature, high humidity, condensation and darkness in
natural climate. By reproducing these conditions, it can merge into
a cycle and let it automatically execute the number of cycles.
2. Standards
Conforms with ASTM G 153, ASTM G 154, ASTM D 4329, ASTM D 4799,
ASTM D 4587, SAE J2020, ISO 4892, all current UV aging test
standards.
GB/T14522-93 National Standard of the People's Republic of
China--Accelerated Test Method for Plastics, Coatings and Rubber
Materials for Machinery Industry Products-Artificial Climate
GB/T16585-1996 National Standard of the People's Republic of
China-Test Method for Artificial Climate Aging of Vulcanized Rubber
(Fluorescent Ultraviolet Lamp)
GB/T16422.3-1997 standard design and manufacture of plastic
laboratory light source exposure test method.
3. Two Ways of Exposure
Ultraviolet aging test box is an important exposure parameter.
Generally, high temperature will accelerate the degradation process
of polymer. The allowable test temperature should be determined
according to the test material and aging performance evaluation
index. Fluorescent ultraviolet lamp emits less infrared than xenon
lamp and carbon arc lamp. The heating effect of sample surface is
basically caused by hot air convection. Therefore, the temperature
difference between the blackboard thermometer, the black standard
thermometer, the sample surface and the air in the exposure room is
very small.
It is recommended the following two exposure modes: exposure modes
1 and 2 correspond to the equipment described in (1) and (2)
respectively. Customers may also adopt other methods, but the
exposure conditions should be specified in the test conditions.
Exposure mode (1)
After a period of light exposure, the sample is subjected to a
cyclic test without irradiation (when temperature changes and
condensation occurs on the sample). The test period is regulated
according to the relevant standards. If there is no prescribed
cycle condition, the following cycle is recommended:
Irradiation exposure lasted for 4 hours or 8 hours at the black
standard temperature of 60±3℃ and then no radiation condensation
exposure lasted for 4 hours at the black standard temperature of
50±3℃.
Note: The aging degradation of some polymers (e.g. PVC) is very
sensitive to temperature. In this case, it is suggested that the
exposure temperature (e.g. 50 below 60 C) should be used to
simulate the colder climate.
When choosing the procedure of radiation exposure followed by
condensation exposure, the allowable radiation or condensation
exposure period can be as short as 2 hours to ensure that the
conditions of each exposure period are balanced.
Exposure mode (2)
The samples were irradiated continuously and tested periodically.
The relevant standards of the test period. If there is no
provision, recommend the following test conditions:
The exposure time was 5 hours under the condition of black standard
temperature of 50±3℃, relative humidity of air (10±5)%. Then the
exposure time was 1 hour under the condition of black standard
temperature of 20±3℃.
Note: (1) In the equipment, the exposed surface of the sample is
wet and moistened through a wet gas condensing machine. Moisture is
generated by heating water in the container placed below the sample
holder.
(2) When the equipment does not conform to Exposure Mode 1, the
method of controlling the relative humidity in the exposed room can
be adopted, or the sample can be sprayed with pure water or water
solution simulating acid rain. Water is referred to GB/T 9344-88.
