for some projects of climate and environmental testing, the test site for environmental testing should be widely representative, capable of carrying out as many test items as possible, and should be as close as possible to the environment in which future operations may be conducted. however, the environmental test site is often different from the real use environment. when selecting a simulated test item, the use requirements of the test item should be analyzed in detail, and the selected test item should not only represent the main use environment, but also speed up the test. speed, save money. during and after the second world war, western countries, especially the united states, established a series of environmental test sites and laboratories, and formulated environmental test standards. the u.s. military stipulates that all weapons, equipment, parts and materials must be sent to the environmental laboratory for simulated environmental tests, and then sent to the environmental test site for field environmental tests. only after passing these tests can they be officially delivered to the troops for use. the u.s. military has included environmental testing as part of its testing and qualification efforts.
at present, national standards have standardized environmental testing, and the state has also formulated environmental testing standards. generally speaking, these standards are similar with minor differences. the standardization of climate environmental testing mainly includes the following environmental testing items:
(1) low temperature test: the test is suitable for specimens that are likely to be used in a low temperature environment during their life cycle. the purpose of the test is to test whether the test piece can be stored, manipulated, controlled and fought in a long-term low temperature environment.
(2) high temperature test: in the test, the weapon is in high temperature air, but not exposed to direct sunlight. the test is aimed at storing or using weapons indoors or in confined spaces or close to heat sources such as engines in high temperature seasons. this test should only be performed if the solar radiation test cannot examine the effect of high temperature. the purpose of the test is to examine the performance of storage or use in a high temperature environment.
(3) moisture-proof test: the test is applicable to weapons that may be used in warm and humid environments. this warm and humid environment is the year-round in the tropics and in the mid-latitudes with seasons of varying lengths of the year. the purpose of the test is to test the weapon's ability to adapt to a warm and humid environment.
(4) thermal shock test: the test is suitable for weapons that are often subjected to extremely rapid temperature changes in the intended use area or mode of use. for example: electronic equipment pods, missiles, optoelectronic devices and bombs in bomb bays on aircraft that take off from desert airports to high altitudes; weapons dropped from high altitudes to desert areas; weapons transferred from indoors to outdoors in arctic regions. at present, only thermal shock tests in air are carried out, and in the future it is possible to carry out thermal shock tests from air into water. the purpose of thermal shock test is to examine the effect of sudden changes in ambient temperature on the performance of weapons.
(5) freezing rain test: the test is applicable to equipment that will encounter freezing rain in normal use. the purpose of the test is to examine the effect of rain, fog and splashed seawater on the equipment's performance after freezing on the equipment, and to evaluate the deicing device and technology.
(6) anti-mildew test: warm and humid conditions are conditions for the growth of microorganisms, which are widely found in tropical and mid-latitude regions. all standard general-purpose weapons and equipment should be designed with mildew resistance in mind. the purpose of the test is to assess the degree of mildew on the weapon and the degree of its influence on the performance or use of the weapon.
(7) sand and dust test: the test is applicable to all mechanical, electrical, electronic and electrochemical weapons used in air with relatively high dry sand or dust content. the test is divided into dust test and sand test. the fugitive dust test uses dust and fine sand, which can enter crevices, cracks, bearings and joints. the sand blowing test uses 149-850 μm (micron) sand particles. large and sharp sand particles can cause erosion and blockage, reducing the effectiveness, reliability and maintainability of equipment. the purpose of the sand and dust test is to test the use and storage ability of the weapon in the sand and dust environment.
(8) solar radiation (sunshine) test: this is a test for weapons and their manufacturing materials exposed to sunlight. solar radiation can cause photochemical and thermal effects. in most cases, this test can replace the high temperature test. the effect of solar radiation on the use or open storage of weapons or related materials can be tested through the sunshine test.
(9) salt spray test: (sulfur dioxide/hydrogen sulfide test) salt is widely distributed on the earth. there is salt in the ocean, atmosphere, ground, lakes and rivers, especially in coastal areas where the salt content is relatively high, and the salt content in the ocean is the largest. there is no weapon that does not come into contact with salt. therefore, all weapons are exposed to some form of salt during their life cycle. the purpose of the salt spray test is to test the influence of salty humid atmosphere on the performance of weapons, especially to test the performance of the coating protective layer and the compatibility of materials.
(10) low-pressure (high-altitude) test: the test is applicable to weapons transported by air in the cargo compartment of an aircraft, and weapons used on plateaus and air-transported weapons experience a rapid drop in pressure after the aircraft is injured. the purpose of the test is to test the performance of the weapon in a low pressure environment and the effect of rapid pressure drop on the performance of the weapon. the maximum height of the simulation can reach 30000m (meters), and the temperature value corresponding to the height is taken during the test.
(11) water immersion test: the water immersion test includes water immersion, dripping water and pressurized water test. the submersion test is applicable to equipment requiring water tightness and equipment used in full or partial immersion in water. in some cases, this test can replace the rain test to verify water tightness. the purpose of the test is to test the ability of the weapon to not leak when immersed in water.
(12) rain test: the test is applicable to weapons that may be exposed to rain during use. the rain test includes the rain test when there is no wind and the rain test when there is wind. the purpose of the rain test is to test the waterproof performance of the rain shielding equipment, and to test the performance of the weapon during and after the rain.
(13) low temperature/low pressure comprehensive test, high temperature/low pressure comprehensive test earthquake simulator can help build houses