College】 【weak mechanical explosion proof elevator --- Power By weak home network 【China】.

<br> an overview of the explosive impact of the explosion site has a good variety of ignition sources, common sources of ignition a fire, electrical sparks, mechanical sparks, static electricity sparks, dangerous high temperature. .Explosion in electrical technology has developed standards of GB3836 and GB12476.1 electrical explosion, the explosion caused by electrical sparks to make clear specifications and mandatory management. .We all know that, according to barrel effect, the overall explosion proof must be done. .Only electrical explosion, the rest will not produce an explosion proof, which due to mechanical shock, high temperature, friction caused by the explosions abound. .Such as: A Paint Factory in South China sodium sulfide plant, two workers handling sodium sulfide black ash extraction, when its the iron stuck drill holes from the operation within the extract smudge, smudge under the force pry loose surface, the .to leveraging busy, suddenly a loud noise, sodium sulfide black ash explosion. .Another example: a workshop for the exclusion resin plant resin hopper discharge port blocking calcium carbide chunks of calcium carbide, two workers were stabbed with an iron bar, sparks, leading to an explosion of acetylene gas mixture. .Another example: a voyage of 47,000 tons in the South China Sea, Japanese oil tanker, a heavy 4.3kg wheel fell into the empty tank from the 15m height of the end of an impact sparks, so that residual oil and gas explosion. .Henan, a flour mill, a worker with low-voltage line lights, line lights as a result the surface temperature of the flour dust explosion detonated. .Elevator is a complete set of equipment, each elevator is made up of many component parts to form many parts of elevator movement and has its own relative motion. .In these sports, some will have impact, and some will produce friction, which are highly impact and friction sparks, the same explosive material will cause an explosion. .The elevator is a lift vertical transportation equipment, people use the elevator during the improper use will also have impact and friction. .Elevator in the course of daily use will be damaged and need repair, maintenance, the repair and maintenance of the process will produce friction and impact. .Therefore, we mainly discuss in this article are explosion-proof elevator mechanical shock and friction. .Second, impact and friction 1. The impact is hidden spark ignition of the fire set off the steel material with high strength and hardness, while the steel strength and hardness, with the carbon content increases. .However, the impact of steel materials production mechanism showed that spark, it is precisely in the carbon steel materials is a source of spark. .Due to mechanical equipment injuries produce flying objects hit, falling objects when the impact, the impact of braking equipment, the impact each other as iron and iron tools may have against the concrete floor has a spark, and become sources of ignition. .2. Friction can generate heat, but also set off the fire ignition source when the two objects in contact, the contact surface is a convex surface uneven, that really is some point. .The friction is the confrontation between the two objects in contact with the relative motion of the resistance, that is, two objects to overcome the adhesive forces between the asperities and the bite force, so the friction with the surface, and pressure. .To overcome this resistance needs to consume energy, this energy into the movement of objects in addition to, it will also become energy, distributed asperities on a hot spot. .Moving parts on machinery and equipment friction, the friction braking motor, rail and linear motion of the friction between the guide shoes, these frictions are not handled well, such as high temperature as the ignition source. .Third, the elevator equipment in the impact and friction in the elevator equipment usage according to their impact and friction is divided into the following categories: normal use of the impact and friction, such as the exchange outside the two-speed braking in the braking, the switch gate crash ., the traction rope and the traction wheel slip, the friction rails and guide shoes. .Use the elevator in the non-normal impact and friction: the car door hit states such as trolleys, objects falling in the car hit the bottom thereof; or traction rope, the compensation chain is running with the anti-hop bars and friction between the rail and bracket .impact. .Incidental non-normal impact and friction: such as speeding elevator fall, the governor action impact, safety clamp transient impact on the rail stop adding friction, impact and friction when its energy is relatively large; car .sink to the bottom hoisting, flying car top rope round traction, traction wheels, on wheels, its energy will detonate explosive objects. .Maintenance personnel in maintenance resulting impact: If the maintenance of the elevator when the knock, twist, spin will have impact and friction. .The size of its force and can be divided into severe, moderate, mild three. .Hit the top speed governor action safety gear sink to the bottom, the traction rope flying out of groove, traction on the rope slipping traction wheel long, two-speed elevator communication Frequent braking, the brake discs on the high temperature, .forklifts, trolleys hit the car door, car radio, black metal weight falling impact the bottom thereof, the maintenance personnel with the tools to beat the elevator is not explosion-proof equipment, can be considered severe impact and friction. .Medium generally refers to the level door, car door shut, turned on impact. .General guidance mild friction between the shoe and the slide. .Fourth, mechanical explosion-proof regional relations with the use of the gas explosion sites are 0, Zone 1 Zone 2 Zone <BR> dust explosion, 20, 21 and Zone 22 <BR> divided according to the explosion sites, Zone 0, .Area 20, there is flammable and explosive substances for a long time the place. .Zone 1, Zone 21 for the normal operation of flammable and explosive substances may be the place. .2, Zone 22 explosive substance for the normal operation impossible, if there is accidental. .This analysis, explosion-proof lift generated due to normal use of the mechanical impact and friction, the maximum can only use one area, 21 area. .The lift generated by normal use moderate to severe impact and friction is not explosion-proof areas, such as the exchange of two-speed brake is not used outside the area and the 21,22 area 1,2. .Elevator in the non-normal incidence of the impact and friction have strict measures and management. .Fifth, mechanical relationship between the level of proof and explosion proof is divided into four grades of gas: methane, Ⅱ A, Ⅱ B, Ⅱ C. . And Ⅱ A, Ⅱ B, Ⅱ C major for flameproof and intrinsically safe setting. .Determine the level of explosion-proof, the main gap and the proof is to be assessed, length of proof. .Determine the level of safety type of explosion ignited the main assessment of the safety of energy. .It can be seen, mechanical explosion proof and intrinsically safe explosion proof type and has nothing to do, but the corresponding Ⅱ A, Ⅱ B, Ⅱ C of the explosive energy of the material ignited the explosion, but not with these substances detonated ignition temperature. .Ignition temperature of explosive substance an explosion limit pressure MESUT ignition energy MIE Explosion proof grade gap <BR> methane 5 ~ 15% 527 ℃ 0.72 Mpa 1.14 mm 0.28μJ <BR> propane 2.1 ~ 9.5% 466 ℃ 0.9 Mpa 0.92 mm 0.26 μJ Ⅱ A .<BR> ether 1.7 ~ 4.5% 170 ℃ 0.92 Mpa 0.87 mm 0.19 μJ Ⅱ A <BR> ethylene 2.3 ~ 36% 425 ℃ 0.8 Mpa 0.65 mm 0.06 μJ Ⅱ B <BR> H 4 ~ 75% 560 ℃ 0.74 Mpa 0.29 mm 0.019 .μJ Ⅱ C <BR> acetylene 1.5 ~ 82% 305 ℃ 1.03 Mpa 0.37 mm 0.019 μJ Ⅱ C methane is not classified is not grouped. .There on the table to see Ⅱ A, Ⅱ B, Ⅱ C corresponding to the explosive material is ignited and the material energy, the spontaneous combustion temperature. .Therefore, corresponding to the severe impact and friction can not be directly used Ⅱ C, measures must be taken to be used Ⅱ C. . Ⅱ B for places should take appropriate measures to determine the resulting explosion of energy and temperature must be within the level. .Six, mechanical explosion proof elevator for 1. .From the elevator speed control energy JB/T10222-2001 wire explosion proof electric hoist and JB/T10219-2001 beam cranes, on the explosion-proof and explosion-proof electric hoist travel speed, lifting speed restrictions were made. .Provisions of the running speed was no more than 25m/min. . Hoist wire rope and reel driving involvement is mandatory. .A maximum of steel wire rope is generally two. .The role of pressure on the rope drum is relatively large, easy to produce energy concentration, the occurrence of sparks. .The use of traction-type elevator, freight elevators are generally rope with five tractors. .The elevator up and down through the traction drive. .The rope on the traction is relatively round, car top, on wheels and so much more pressure to be small. .Lift standards require that all wheel diameter is 40 times more than steel wire rope, wire rope traction hoist large bend radius ratio, and the rope in the oil hemp rope core is the core force in the leaking oil will keep the surface of the traction rope lubrication .state. .Driving the wheels and electric hoist trolley wheels in orbit, is the relative of steel and steel friction movement. .In JB/T10219-2001, the limit shall not exceed the speed of 25m/min. . Relative to the elevator rails and guide shoes are running up and down vertically. .Does not exist, like driving, electric hoist moving parallel to the wheel so much pressure. .Lift the fuel rail with specialized devices, always maintain the elevator guide rail and guide shoes for good lubrication condition. .Furthermore explosion-proof nylon elevator guide shoe is generally non-ferrous metal materials or alloys of copper with no spark, no spark or friction heat. .Based on the above analysis and comparison, the rated speed of the elevator explosion generally 0.5m / s, that is 30m/min. . No more than 60m/min. . If more than 30m/min, reliable lubrication of the traction rope should be measures to reduce the wire rope and traction sheave wheel or friction between. .Rail oiler must work reliably. .Jiaoding round on wheels, guide wheels, and ropes should be of high grade bearings. .Always check the surface of the traction rope, should be no broken wires. .With progressive safety gear, clamp block, steel products or steel can not be used without spark coating surface treatment. .Because of progressive safety gear for some slippage in the braking process. .In this process, will be processed without apparent loss of spark protective layer, will produce sparks. .2. .Structure to reduce the friction from the single speed or two speed AC motor brake should be installed inside the explosion-proof enclosure. .Such as the selection of frequency control motors, VF drag the elevator, because it is zero speed brake, the brake between the brake wheel and the brake pads can be no explosion protection. .Department of gearbox bearings, motors and bearings, guide wheels, running at high load bearing at high level to use or maintain the lubrication of bearings. .If the folder by folder rope rope in the role of the surface of the surface can not produce sparks. .3. .Select from the material appears to prevent mechanical spark is easy to produce severe impact on the site should be used not angry material, such as the impact speed at the braking, safety gear at work in the jaw, Ⅱ C grade for four weeks and the elevator car .car floor office. .Occurrence of the elevator car safety gear is a safety measure last fall. .Therefore, the safety gear is a key component of the elevator. .In order to ensure reliable safety gear will speed falling elevator car stopped atthe rail system, safety gear clamp block must have a certain hardness. .Therefore, the safety gear of the clamp block is 45 # steel production. .The surface hardness HRC40 ~ 45. .Safety gear to prevent sparks in the system stopping time, must take no sparks measures to clamp the block. .Current domestic production of explosion-proof elevator clamp block and clamp block with bronze coating treatment. .But in general the hardness of bronze is about HRC35. .Safety gear clamp block as easy to produce skid, the system can not reliably stop the car. .The clamp block coated to maintain the clamp block hardness. .But the coating easy to wear, the instantaneous safety gear can only be used: for the elevator speed 0.63m / s below the elevator. .Southeast of Suzhou Elevator Company is currently using a new material, its hardness more than HRC40 sufficient to guarantee that the system stop the car without spark occurs, the material can be applied to progressive safety gear. .Can be used for speed of 1m / s (60m/min) of the elevator. .Ⅱ C grade for the elevator car and the car around the end of the state board may also use non-metallic materials, but must consider the anti-static measures. .Elevator Buffer should be non-metallic materials, non-metallic surface resistance of the buffer not more than 109Ω. .Explosion-proof elevator maintenance and repair personnel must use non-sparking explosion-proof tool. .4. .Generated from the management to prevent accidental collision repair and maintenance must be explosion-proof elevator manufacturers have identified and qualified repair and maintenance unit for repair and maintenance. .Maintenance personnel must be explosion proof elevator knowledge training. .The maintenance of explosion-proof elevator maintenance to be taken in advance the main protection. .Elevator speed governor to prevent the occurrence of safety gear. .Always check the lubrication site. .Traction rope to prevent the occurrence of bearing and dry friction. .Found broken wire rope traction should be promptly replaced. .<BR> Staff on the use of the elevator lift to enhance civilization with education. .No brutal and rough handling, strict implementation of rules for explosion-proof elevator use. .Explosion proof elevator machinery. .There are still many problems to be further explored. .Mechanical proof of this paper is taken into account the safe use of the lift under normal mechanical explosion-proof measures, not including the installation does not place such as field plate and the traction rope rope friction, traction rope friction with cement floor, the compensation chain and guide .rail bracket collision, car collision with the floor door. .Therefore, mechanical explosion proof elevator, only to be considered on the design and manufacture, installation and acceptance at the time of installation quality is also extremely important. .<BR>.