Regardless of which type of product, in order to ensure its own performance, especially in the actual use of the normal work, they are often tested in all or part of the environmental conditions.
1. Concepts and functions of environmental tests Environmental tests are conducted by exposing products or materials to natural or artificial environments and testing them under specified conditions to evaluate their performance under conditions of storage, transportation and use that may actually be encountered. .
2. Environmental test methods Environmental tests include natural exposure test, field test and artificial simulation test. The first two types of tests require high cost and long time, and the repeatability and regularity of the test are also poor. However, the problems found in the test can reflect the actual use state more realistically. Therefore, the two tests are artificial simulations. The basis of the test. Artificial simulation environmental tests are widely used in quality inspection. In order to make the test results comparable and reproducible, the basic environmental test methods for products are now standardized.
The common methods of environmental testing are as follows:
(1) High and low temperature test: used to assess or determine the adaptability of the product for storage and/or use under high and low temperature environmental conditions.
(2) Temperature shock test: Determine the adaptability and structural bearing capacity of the product under one or several consecutive temperature changes.
(3) Damp heat test: It is mainly used to determine the adaptability of the product to moist heat (whether or not condensation occurs), especially the electrical and mechanical properties of the product; it can also be used to check the ability of the test sample to withstand certain corrosion. .
1 Constant damp heat test: generally used for products whose moisture is mainly absorbed or absorbed, and only permeated (or diffused) without respiration. The purpose is to evaluate whether these products can maintain their required electricity under high temperature and high humidity conditions. Performance and mechanical properties, or sealing insulation, can provide adequate protection.
2 Alternating Damp Heat Test: This is an accelerated environmental test used to determine the suitability of the product for use and storage in the hot and humid environment of temperature cycling and which typically produces condensation on its surface. It uses the respiration of the product with the change of temperature and humidity to change the humidity inside the product. The test product is subjected to four stages of temperature rise, high temperature, temperature drop and low temperature in the alternating heat and humidity test chamber to form a cycle. Several cycles of testing were carried out as specified in the technical conditions.
3 Normal temperature damp heat test: The product is generally tested under the conditions of high normal temperature and relative humidity.
(4) Anti-corrosion test: Check the resistance of products to salt water or industrial atmosphere corrosion, widely used in electrical and electronic, light industry, metal materials and other products. The anticorrosion test is divided into an atmospheric exposure corrosion test and an artificial accelerated corrosion test. In order to shorten the test period, artificial accelerated corrosion tests are often used, and most of them are tested with neutral salt spray. The salt spray test is mainly used to determine the corrosion resistance of protective decorative coatings in a salt spray environment, and to evaluate the quality of various coatings.
(5) Mold test: The product is stored and used in a high temperature and humidity environment for a long time, and the surface may have mold growth. The hyphae easily absorbs moist gas and secretes organic acidic substances, so that the insulation performance of the product is destroyed. The strength is lowered, the optical properties of the optical glass are degraded, the corrosion of the metal parts is accelerated, the appearance of the product is deteriorated, and sometimes the disgusting musty smell is accompanied. To this end, a mold test of the product is carried out to evaluate the effect of the mildew range or the mildew on the performance and use of the product.
(6) Sealing test: Determine the sealing ability of the product to prevent dust, gas and liquid leakage. Sealing can be understood as a protective ability of the product's outer casing. There are two types of protection for outer casings of electrical and electronic products in the world: * are anti-solid particles (such as dust); the second is anti-liquid, gas. The dust-proof test is to check the sealing performance and working reliability of the dust-proof structure of the product in sand and dust. The gas and liquid sealing test is to check the ability of the product to prevent gas and liquid leakage under strict working conditions.
(7) Vibration test: Check the adaptability of the product to sinusoidal vibration or random vibration and evaluate the integrity of its structure. During the test, the product was fixed on a vibrating test stand to vibrate in sequence in three mutually perpendicular axes.
(8) Aging test: The ability of polymer material products to resist the influence of environmental conditions. According to different environmental conditions, there are atmospheric aging test, heat aging test, ozone aging test and so on.
1 Atmospheric aging test is to expose the sample to the outdoor atmospheric environment, and after undergoing a combination of various factors for a certain period of time, observe the performance change of the sample and evaluate its weather resistance. The test shall be carried out in an open-air exposed site, and the environment of the exposed site shall be representative of the harsh conditions of a certain type of climatic characteristics or conditions that are similar to the actual application.
2 The heat aging test is to place the sample in a heat aging test chamber for a certain period of time, and take out the sample and place it under the specified environmental conditions to measure its performance and compare it with the performance before the test.
(9) Transportation and packaging test: Most products entering the circulation field involve transportation packaging problems, especially the transportation and packaging of various types of precision electromechanical, instrumentation, household appliances, chemicals, agricultural and sideline products, medicines, food and other products. The transport packaging test is a comprehensive test to assess the ability of the package to withstand dynamic pressure, shock, vibration, friction, temperature and humidity changes and the packaging's ability to protect the contents.
3. Passing the basic conditions of the environmental test After the environmental conditions are tested, they can generally be passed when they meet the following requirements.
(1) The technical performance of the product meets the requirements of the technical standards or the operational guidance documents of the test. The product functions normally without any faults or defects. Electrical products and components have normal insulation properties.
(2) The product and the disintegrable component shall be inspected for no falling, looseness, cracks, breakage, damage, deformation, abnormal wear and other undue defects.
(3) Appearance inspection of the components of the product, the surface coating of the metal parts does not appear peeling, blistering, rusting, discoloration, etc.; the surface of the non-metallic parts does not appear to swell, blister, crack, fall off, plaque, etc.; Bonding, aging, cracking, etc.
The environmental test has great damage and damage to the product. The product after the general test can not be used directly. It needs to be disposed, refurbished according to the prescribed procedures and passed the inspection before it can be delivered.
Take the original herbs, remove impurities, wash water, Run through, cut thin slices, dry. Or use when crushed, Coptis should not over 14.0% of the standard moisture, the total ash content of not more than 5.0%, dilute alcohol extract not less than 15.0%. Berberine hydrochloride is not less than 5.5% berberine, berberine not less than 0.80%, berberine not less than 1.6%, palmatine not less than 1.5%.
High Standard Coptis,Berberine Pieces,High Standard Berberine,High Standard Coptis Chinensis
Chongqing Taisun Pharmaceutical Co., Ltd. , https://www.taisuncoptis.com