1. The scope of the test must be required to meet the scope of the product failure possibility test, ie whether the high or low temperature box or the cold and hot shock box should be able to meet the extreme temperature conditions specified in the test requirements.
2. The test equipment must be selected to ensure that the volume of the test sample does not exceed 1/5 of the working volume of the test equipment.
3. In order to ensure the uniformity of the temperature in the test area, whether to use forced air circulation or forced air circulation is selected according to the heat dissipation of the sample. For example, the LG type drying oven produced by Shanghai ESPEC adopts the natural convection of hot air, which is particularly suitable for powder drying. The LC type drying oven uses the forced circulation of hot air. The difference in equipment temperature distribution will have a greater impact on the test results. When larger samples are used, or when the number of samples tested at the same time is large, the results of the tests will vary greatly with location and should therefore be Choose equipment that has as good a temperature uniformity as possible. For example, the Z series thermostat produced by Shanghai ESPEC has a homogeneity of 2.0°C.
4. The sample temperature has two ways of adopting upwind and downwind sensor temperature measurement. The position of the temperature control device and the control method of the device can be selected, and a suitable device should be selected according to the test requirements.
5. To prevent the sample from absorbing heat or releasing heat due to heat radiation or heat conduction in the test area, the device's heating or cooling system must not affect the sample.
6. It is easy to record and display. It is required to install automatic counters, indicator lights, recording equipment, and automatic shut-off instrument devices during the cycle test.
7. Easy sample placement A rack for placing or hanging can be required, and the rack does not change its mechanical properties due to high or low temperature changes.
8. There shall be lead holes for introducing the test power into the working chamber of the device.
9. Protection measures must be taken for the damage of the sample and the safety of the test personnel. For example, observation windows and lighting are provided, and there are alarm devices such as power-off phase, water shortage, over-temperature protection, and operator protection.
10. Do you need remote monitoring function?
Precautions when using temperature test equipment:
1. Temperature and humidity deviations may occur during upsampling and downdraft tests on large samples. Therefore, careful consideration should be given to the placement of the sample. Place as much as possible in the center of the working space of the test equipment. The samples should not be in contact with each other and overlap, and there should be a certain interval to allow the air to circulate. Also, it should be ensured that the sample is easy to move during the test and it is easy to replace the sample during the test.
2. Check whether there are volatile substances such as oil and gas in the test area and check for odorless substances. The test results of such substances must be confirmed in advance.
3. Pay attention to confirm the temperature condition of the test sample in the test area.
4. In order to maintain the same temperature in the temperature zone, it is necessary to ensure that the temperature of the test environment and the fluctuation of the power supply of the equipment are as small as possible to ensure that the test sample does not generate heat radiation and does not absorb heat so as to ensure a stable temperature in the test zone.
5. After the temperature test equipment is finished testing, quickly removing the test sample will cause unnecessary strain on the sample and may give unexpected results. Therefore, the sample must be taken out after the test sample has cooled to ambient temperature.
6. The thermal conductivity of the test sample installation and support bracket should be low to ensure that the test sample and the mounting and support brackets are in a thermally insulated condition.
The test content of different products is determined jointly by the test requester, designer, and tester. From the perspective of providing test equipment that conforms to the test, a technical specification framework for the test equipment is established. The test equipment supplier can provide specific specifications of the equipment according to this framework. Every test equipment that can simulate the test environment generally has a measurement system, so using off-the-shelf equipment and buying new equipment is very easy. Simple test equipment can also be manufactured by yourself, but consider the cost, the reliability of the test results, the degree of precise control, and the safety factors for continuous operation.
Conclusion Environmental testing is a process that can add value to products and cannot be ignored. The temperature-based environmental test, as the most basic one in environmental testing, has a wide range of applications, greatly improving the environmental adaptability and reliability of military and civilian products in China, and directly leading to the improvement of product quality. This article gives a simple basic introduction to the temperature stress and related temperature-type environmental testing equipment, and accurately selects and uses according to the use requirements in order to achieve the real purpose of the environmental test.
Coalescence &Separation Filter Elements
Describe:
The coalescence separation filter element is generally cylindrical in shape, and the coalescence separation filter element is used in the oil-water separation system, mainly separating the oil-water mixture, suspension solution, emulsion solution, etc. The application flow of coalescence separation filter in the system can be divided into solid-liquid separation-demulsification-coalescence-separation. In the system, the number of Coalescence Filter and separation filter is better than that of 3:1, the effect of coalescence is good and the separation speed is fast.
Principle and characteristics:
The surface treated glass fiber or polyester fiber is mainly used as the coalescence medium. The structure of the Filter Material is 0.1 μ m by special design. The filter medium has good coalescence performance. Working process: after the emulsified oil enters the coalescence separator, it first enters the inner filter core from inside to outside, and the small liquid droplet in the dispersed phase changes from small to large. Finally, it falls off on the surface of the coalescence filter core and completes the coalescence process. In the process of flow separation, the larger water drops sink into the sink by gravity, and the small water droplets flow along with the oil to separate the filter elements. The separation filter has hydrophilic effect to block the passage of water. Small water beads collide to form large water droplets, which then settle into the sink again, thus dehydrating the oil.
Different packing sizes should be selected according to different oil-water systems: the smaller the packing size, the larger the specific surface area per unit mass and the larger the contact area with droplets. As a result, the performance of the coalescence filter element is enhanced. Therefore, it is suggested that the separation efficiency of coalescence filter should be taken into account when choosing fiber size, and the pressure drop should be taken into account at the same time.
Range of applications
1. Aviation fuel, gasoline, kerosene, diesel.
2. Cyclohexane, isopropanol, cycloacetone, etc.
3. Turbine oil and other low viscosity hydraulic oil, lubricating oil.
4. Other hydrocarbon compounds.
5. Liquefied petroleum gas, stone tar, benzene, toluene, xylene, cumene, polypropylbenzene and so on.
Coalescence &separation Filter Elements
Ptfe Membrane,Separation Filter Elements,Coalescence Filter Elements,Coalescence Filter
Henan Sinofiltec Technology Co.,Ltd , http://www.sinofiltec.com