Everyone knows the electrostatic hazards , and now more and more manufacturers have begun to implement various degrees of anti-static measures and projects. But to realize comprehensive and effective anti-static works to follow the actual situation of different enterprises and objects of different jobs , develop appropriate countermeasures. Anti-static measures should be systematic, comprehensive , otherwise , it may be less effective , even devastating side effects. Here we talk about the specific anti-static workshop method .
An anti-static work area venues
1: The ground material : ground should be selected by the electrostatic conductive material, such as anti- static floor or ground in the general spread fortified static mats and effectively grounded. Prohibit the direct use of wood flooring or laying wool, linen, chemical fiber carpets and general leather floor .
2 :Grounding : an anti-static system must have an independent and reliable grounding , grounding resistance should generally be less than 10Ω, laying and testing methods shall comply with the requirements GBJ 97 's . b, anti-static ground zero may not be connected to the power line , may not be shared with lightning ground . c, using a three-phase five -wire power supply , which can be used as anti-static earth ground wire ( but zero line, the ground may not blend ) . d, grounding trunk cross-sectional area of not less than 100mm2; branch trunk cross-sectional area of not less than 6mm2; equipment and bench grounding wire should be used cross-sectional area of not less than 1.25mm2 deposited plastic multi-strand wire , ground wire to the yellow-green color of the line appropriate. e, grounding backbone connections should be soldered . f, anti-static devices connected terminals should ensure that access to reliable , easy assembly and disassembly, allowing the use of a variety of clip-on connectors, such as the Ngok fish folder , plugs and sockets , etc. g, higher requirements for grounding resistance grounding system should be installed workplace monitoring and alarms , such as : SL-038A grounding system monitoring and alarms can be monitored at any time contact with the ground and the earth is good .
3 :Ceiling material : static type should be used , under normal circumstances allow the use of gypsum board products , prohibit the use of ordinary plastic products.
4 : Wall fabric : Use anti-static type wallpaper , under normal circumstances allow the use of gypsum or lime paint wall paint , wallpaper and prohibit the use of ordinary plastic wallpaper. 5 :Humidity control : a, anti-static work area environment relative humidity of not less than 50 % is appropriate. b, the product does not cause harmful effects under the premise that the device allows the use of a humidifier or water spray formulations to increase the ambient humidity . c, computer room humidity should comply with the relevant provisions of GB 2887 , similar to the engine room shall also comply with this requirement.
6 : Anti-static work area regional boundaries should be marked regional boundaries , and hang in a prominent place warning signs, warning signs should be consistent with the provisions GJB1649 entrance to the work area should be configured ionized air air bath equipment.
7 : the static power : anti-static work area prohibit the use and exposure of the product is easy to produce electrostatic charge . Painted or varnished surfaces such as table surfaces , ordinary plastic veneer, ordinary vinyl and resin surface flooring, plastic and general floor leather, polished wood floor waxing . Ordinary vinyl overalls , hats , shoes, ordinary polyester , nylon synthetic fibers and fabrics , plastic and rubber-soled shoes ordinary operation of tools and equipment , ordinary plastic boxes, frames, bottles , plates supplies and paper products, ordinary foam and general mobile tools compressor , injection apparatus , and evaporated equipment.
Second, the production site of application and management of Static
1 The ground Static grounding is to connect several devices to one or the other ground. Buried in the ground using a method to establish an "independent " ground . The resistance between the earth and the earth <10Ω, it is possible to gather on the role of conductor bleed charge , for the accumulation of static electricity on a conductor ( such as humans ) usually grounded approach to guide go. Ground by the following method :
① Body through the ESD wrist strap grounded.
② the body through the ESD shoes ( or shoelaces ) , and ESD floor mat .
③ countertops grounded.
④ test equipment , tools, folders, iron grounded.
⑤ anti-static flooring ,ESD mats grounded.
⑥ antistatic transport vehicles, containers, racks as grounded.
⑦ anti-static chairs grounded.
2 :ESD safe workbench :
① the table,ESD mat , ESD wrist strap connector and ground wire and other components. When necessary, should be equipped with static equipment , such as: ion fan .
② ESD mat should be on more than two ESD wrist bands connectors, one for the operator to use , one for technicians , inspectors use .
③ ESD safe workbench does not allow stacking plastic boxes, rubber , cardboard, glass and other debris is easy to produce static electricity, drawing data files should be placed in an antistatic bag .
3 :Static elimination equipment : static -prone product assembly work bench should put an ion fan, ion fan blowing in front of the product can be produced at any static electricity quickly eliminated.
4 :ESD wrist strap : direct contact with electrostatic sensitive devices must bring an antistatic wrist strap , wrist strap should have good contact with human skin , wristband system should range within 750KΩ-10.5MΩ ground resistance values ​​. Antistatic wrist strap should always hand wrist strap tester to detect damage. Our production available wrist band tester . Conditional or require relatively high company is best to use the wrist strap on-line monitor , because the use of the line monitor wrist strap handles and ground connected. So it can be readily detected antistatic wrist strap is damaged or whether workers wear .
5 :ESD garments: Into contact with static-sensitive devices personnel and personnel anti-static work area must wear anti- static clothing , especially in the relative humidity less than 50 % of the dry environment ( such as winter ) . Workwear fabrics should comply with the relevant national standards.
6 :ESD shoes : Enter anti-static work area should wear anti-static shoes. Wear ordinary shoes should use conductive footwear beams , anti- static shoes or heel strap. Anti-static shoes often use human tester to detect its anti-static properties.
7 :ESD socks : anti-static socks for many companies do not pay attention , in fact, this is not right. The best time to wear anti-static shoes to wear anti-static socks, if there is no anti-static cotton sock socks can also be worn , but should not wear nylon sock , nylon sock because of poor conductivity , prevents static guide to the anti-static shoes to walk , sometimes measured using the human tester qualified anti-static shoes pair found resistance is too high , it is because of the reason to wear nylon sock .
8 :ESD containers: bag containing components production sites , turnover box , PCB magazine rack , etc. should have electrostatic protective effect, does not allow the use of metals and ordinary container , if necessary , storage components used containers should be grounded.
9:The production line with the conveyor belt and the drive shaft should be fitted with anti-static grounding brushes and rods. Belt surface can be used for static elimination equipment, such as : ion fan and ion wind wand .
10 :Production sites using the assembly fixture, test fixture , welding tools, a variety of instruments , etc., should set a good grounding line.
11:Human tester : production sites should be installed at the entrance of human tester, every person entering the production site should be carried out anti-static tests before entering the scene after passing .
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