First, the determination of the illumination of the clean factory and the choice of light source
The clean workshop is generally a closed factory with large column net, large span, large space and no light-harvesting window. The illuminance value of the clean room of the lighting window is clearly defined in the Code for Design of Clean Plants GB50073-2001 (see Table 9.2 in the specification). .3), and stipulates that the general illumination in the mixed lighting without the light window clean area is not less than 200 1x, which is one level higher than the 150 1x in GBJ73-84. The International Lighting Commission (CIE) “Indoor Lighting Guide†stipulates that the illumination of a windowless building shall not be less than 500 1x. According to China's existing power level, China's artificial lighting illumination standards are generally lower than those of Europe, the United States and other countries. In fact, some Chinese-foreign joint ventures and foreign-owned clean factory buildings have much higher illumination than 2001x, reaching 300~500 1x. At present, the country is formulating "Design Standards for Industrial and Civil Building Lighting", and the illumination standards in the new specifications will be greatly improved. However, considering the light and dark adaptation of the production workshop, the illumination level of the clean room, the illumination of the lounge and the illuminance level of the work can not be too different. Generally, the difference between 1 and 2 is appropriate, but the minimum cannot be less than 100 1x. The standard for the clean room with window is the same as that of the ordinary production plant according to the current national standard "Industrial Enterprise Lighting Design Standard" GB50034-92.
The illumination of different clean industrial plants varies greatly according to the process requirements. For example, the illumination of hybrid lighting in the electron gun assembly workshop of the CRT factory should reach 1000~3000 1x. In addition to setting general lighting, local lighting should be set. The proportion of mixed illumination illumination should not be too large, and the general illumination illumination is 5~15% of the mixed illumination illumination. In China, due to the tight power, the proportion of illumination of local illumination in hybrid lighting has been expanded. If the space illumination is low, it is easy to cause glare, which makes people feel tired, but the brightness of the light source can not be too high, and a linear light source such as a fluorescent lamp or an incandescent lamp with frosted glass is often used.
2. Selection and arrangement of general lighting fixtures for clean workshops
In order to design a clean room with a high cleanliness level, we first introduce the cleanliness level of clean buildings and the flow pattern of clean air. In the new "Code for Design of Clean Plants" GB50073-2001, the air cleanliness level has been revised more. The air cleanliness specified in GBJ73-84 is divided into 4 levels, namely 100, 1000, 10000. 100000 class, with the rapid development of microelectronics and integrated circuit industry, the clean room has higher and higher requirements for air cleanliness, and it is required to control the particle size of dust particles to less than 0.1μm. In order to be in line with international standards, the new specification is equivalent. According to the relevant provisions of the international standard ISO14644-1, the air cleanliness level has been increased from 4 levels to 9 levels, namely level 1 and level 2. . . . . . Level 9.
In the specification, the choice of the flow pattern of clean air is also clearly defined. “When the air cleanliness level requires 1 to 4, vertical unidirectional flow should be used; when the air cleanliness level is 5, vertical should be adopted. One-way flow or horizontal one-way flow; when it is 6~9, non-unidirectional flow should be adopted. The so-called airflow pattern is a reasonable design of the flow pattern and distribution of clean indoor air. Its characteristics: should consider to avoid or reduce eddy current, is conducive to the rapid and effective removal of pollutants, should limit and reduce the spread of dust and bacteria emitted by indoor pollution sources, to maintain the air cleanliness level required by the indoor production environment.
Due to the special nature of the clean room, the selection of general lighting fixtures should be smooth, the surface of the bumps is less than ash, easy to clean and use lamps that are not suitable for the production of electrostatic materials. In addition to meeting the illumination requirements, the selection and arrangement of the lamps should mainly be considered according to the indoor airflow pattern. When the ceiling is a vertical one-way flow air outlet, such as the lithography workshop of the VLSI plant. . . . . . The area of ​​the high-efficiency filter air supply opening can sometimes reach about 80% of the ceiling area, which brings difficulties to the arrangement of the lamps. At this time, the teardrop type fluorescent lamp should be selected, which has less influence on the airflow and can be installed in The underside of the aluminum profile frame for high-efficiency filters (see Figures 1 and 2) not only hinders the supply of air but also effectively utilizes the only ceiling space. Depending on the ceiling module, different lengths of the lamps can be selected.
For non-unidirectional flow clean room, triangular ceiling fluorescent lamp or box ceiling fluorescent lamp should be adopted. The arrangement of the lamp is preferably continuous ribbon type or intermittent light band type, and is arranged with fire alarm detector and air conditioning tuyere. . For example: the electron gun assembly workshop of a picture tube factory, with an area of ​​2160m2 (60×36), adopts double-tube triangular ceiling fluorescent lamps, with 12 rows of intermittent escape belts, 20 lamps per row, the effect is better, sucking When installing the top fluorescent lamp, pay attention to the method of sealing and sealing with the sealant to ensure the pressure difference between the clean room and the pollution.
The horizontal one-way flow clean room, the building height is not too high, the sending and returning air ports are installed on the side wall, the ceiling is convenient for the lamp arrangement, and the embedded fluorescent lamp can be used to minimize the influence on the air flow.
3. Selection and arrangement of emergency lighting fixtures for clean factory buildings
The clean workshop is a relatively closed body. The flow route of the indoor personnel is complicated. In order to facilitate the accident in the shortest time, people can leave the accident site in the shortest time to ensure the safety of life. The national code stipulates that “the evacuation indicator should be placed on the top of the fire exit door or on the wall of the evacuation walkway and its corner at a height of 1 m below the ground. The distance between the signs on the walkway should not exceed 20 m.†“Evacuation lighting on the passageway†The standard value of illuminance should not be lower than 0.51x.
The dedicated fire exit is a dedicated entrance for firefighters to enter the building for fire fighting. The special fire exit is set up to enable firefighters to quickly and effectively enter the core part of the plant in the event of a fire. The "Clean Plant Design Code" stipulates that "the red emergency light should be set at the special fire exit" in the actual project. Most designers can notice that the setting of evacuation lighting should include the settings of evacuation pointing signs and evacuation exit signs, but the setting of evacuation channel lights is ignored by some designers, especially the special fire ports are often ignored. Emergency lighting settings.
Standby lighting should be provided in the clean room; alternate lighting is used to ensure that normal lighting can continue to perform normal activities. For clean workshops with diesel generators, the backup lighting power supply can be provided by diesel generators; for clean buildings without diesel generators, the backup lighting power supply can be connected to different transformers from the normal lighting mains. Or separate from the normal lighting power supply line from the substation's low voltage screen (or busbar).
The standby lighting in the clean room should be evenly arranged according to the proportion, and the illuminance should not be lower than 10% of the general lighting. The lamps can be selected to be the same as the general lighting fixtures in the clean room. The lamps with the battery inside are usually used as normal lighting work, and automatically when the power is cut off. Transfer to emergency lighting, this function is independent, simple wiring, flexible application, and limited by external power supply.
Fourth, energy saving in clean factory lighting
The illumination illumination requirements of clean workshops are higher than those of ordinary factories. The indoor ceilings are short, and the energy consumed by illumination is large. It is generally suitable to use fluorescent lamps as the light source. However, choosing different types of fluorescent tubes is also important for improving light efficiency and saving energy. It is recommended to use a T8 (36W) lamp with a trichromatic phosphor or a T5 (28W) lamp. The T8-type lamp produced in China in the late 1980s has improved the luminous efficiency by 15%~30% compared with the T12 (40W) type lamp produced in China for decades. It has gradually replaced the T12 lamp, and it was developed in the mid-1990s. Take out the T5 type lamp. Recently, a T2 type lamp has been developed. China has produced T8 tubes for more than ten years, the quality has become stable, and the output is relatively large. The T5 tube will be the development direction, but the production time is not long and can be used. The phosphor material in the lamp tube, which has evolved from ordinary powder to trichromatic rare earth phosphor, is also an important indicator of technological progress. Taking the 36W super straight tube lamp produced by Philips with three base toners as an example, the luminous efficiency of the T8 tube produced by ordinary powder is increased by 17.5%, the life is extended by 50%, and the color rendering is improved from 63 to 85, but the price of a single lamp is required. It is about 140% higher, but it is economically justified.
The use of electronic ballasts or energy-saving magnetic ballasts can also achieve energy-saving purposes. Compared with traditional magnetic ballasts, electronic ballasts and energy-saving magnetic ballasts for fluorescent lamps have low power consumption and high energy efficiency factor. Save electricity costs, but the price is high.
For example, if 5,000 ballasts are used in the clean project, three shifts are used, and electricity is used for 24 hours, then the use of electronic ballasts or energy-saving magnetic ballasts can save energy.
It can be seen from the above table that the use of electronic ballast can save 240,900kwh of electricity per year, and the electricity price of 0.5 yuan/kwh can be saved by 120,000 yuan per year. The energy-saving magnetic ballast can save 175,200kwh and one year. It can save 87,600 yuan.
In addition, lighting energy saving measures include:
·Select reasonable illuminance standard values; ·Select suitable lighting methods, and adopt mixed lighting mode in places with higher illuminance requirements; ·Select lighting control mode reasonably, use zone control light according to the characteristics of use and increase lighting switch points appropriately.
Five, clean factory lighting wiring should pay attention to the problem
The lighting and wiring of clean workshops should be the same as all kinds of electrical lines and professional pipes, following a "hidden" principle. The airflow pattern of the clean room is different, and its building structure is also different. The non-unidirectional flow clean room generally has only the upper technical interlayer or suspended ceiling; the vertical unidirectional flow clean room has the upper and lower technical interlayer, and the upper technical interlayer is the air supply static. Pressure box, circulating air treatment device, high efficiency filter, part of power, lighting, communication pipeline are also laid here; the lower technical interlayer is return air static pressure box (return air passage), generally laying water pipes, gas pipes, electrical pipelines, cables Bridges, enclosed busbars, etc.; adjacent to the clean room with technical bypass or technical shaft, laying vertical pipes or placing auxiliary production equipment that should not be placed in the clean workshop.
Because the location of the luminaire is often located in the technical interlayer or technical tunnel above the ceiling, the lighting distribution box is easy to access the load center, and the horizontal wiring is short and concealed.
There is only a clean room with a suspended ceiling. The pipeline inside the ceiling is complicated. Pay attention to the fact that the electrical pipeline should be kept away from the explosive gas pipeline or take relevant measures. The lighting distribution box and switch that must be installed in the clean room should be concealed as much as possible. The cable pipeline must be sealed through the ceiling to prevent dust and bacteria from entering the clean room.
Conclusion
The clean workshop has many pipelines, complicated professional technology and strict requirements. Its design requires a variety of professional and technical cooperation. It is a comprehensive and extremely strong engineering design. Lighting is an important part of it. The illumination illumination is determined, the light source and the lamps are Selection, arranging of lamps and coordination of construction and equipment are important topics in the design of clean factory lighting. A good clean factory lighting design makes the illuminating space suitable for bright, and the use of ceiling space is reasonable, and the lighting can be achieved by cleverly arranging and installing lamps. Aesthetic, comfortable, uniform illumination, reasonable airflow organization, can also ensure the cleanliness requirements of clean workshops, energy saving and convenient maintenance management.