【 Weak current College 】 material hoist gantry, shaft bracket safety supervision points

Lifting of classification has lifts, lifts typically include: manned dual-use goods elevator, elevator and material hoists. This checklist is a material hoist the gantry and mast material hoist safety technical specification of the law.

(A) the shelf productions
1. current manned elevator and dual-use goods elevator has been produced by the factory fixed-point production and material hoists, especially in the lower rack (height in 30m following) winder, most is not a manufacturer's product, but the enterprise's own production, to eliminate structural design produce no basis to the process requirements, the acceptance without detection means, crude gamut made that, in use do not meet the requirements, caused the accident, provided:
(1) the shelf must be in accordance with the gantry and mast material hoist safety specification (hereinafter referred to as the "standard") at the request of design computing and superior departments and Chief Engineer's approval.
(2) the specification of the shelf for rack portal and wells, and enhance the institution is to ground winch powered, along the Rails do vertical run of the hoist.
(3) of the code does not include use of scaffold tube and fastening material, erection in temporary construction site, and the Derrick is the use of prefabricated steel materials into parts or standard section, to the construction site in accordance with the design drawings for Assembly of the shelf.
2. If the use of the product, manufacturers should have the relevant departments of the identification of the material and municipal construction safety regulatory agency issuance of licence card.

(Ii) limiting device
1. once the docking device
Material hoist is only allowed for delivering materials are not allowed to load lifting equipment, but when loading of the basket when running in place, still need workers to lift materials within the prison. At this point due to operators, the need for a safety device on job security for protection, namely when the basket of wire rope suddenly disconnected, the basket of the workers will not be harmed.
(1) secure docking device. When the basket when running in place, the docking unit can be positioned in hanging baskets, and can reliably bear basket weight, rated load and hanging baskets inside staff and delivery of items of work load. Now load all device by the dock, hoist rope only plays the role of insurance. Safety check should act test validation.
(2) rope protection device. Safe dock another type, i.e. when the basket is running in place workers into the basket inside, or run up and down when the basket, if broken rope, this device quickly once the reliably stopped and fixed on the shelf, make sure that the basket in exposed workers from harm. But many accident case, this kind of equipment reliability, rope must be equipped with protective devices, also requires secure docking device.
2. safety devices should be stereotyped
Or call the superior limit restrictor, main role is to limit the rise in altitude, the nacelle (once the rise of the highest location and day of distance beam minimum should not be less than 3m), this distance is considered an unexpected situation, the power supply cannot be disconnected, the basket will continue to rise, may result in more accidents, and this can make use of the emergency power off switch drivers cut off the power to prevent the hanging basket and days pounding. Safety check should act test validation.
(1) when the power adopts reversing winches, ultra high-limit can be taken off the upgrade power supply, motor to operate the parking brake, and then make the basket when motor reversing decline.
(2) when the power adopts friction winch, ultra high limit will not be allowed to take off the lift power otherwise occur as a result of lifting power supply is cut off, all of a sudden decline in the nacelle. Should be used in place of alarm (Bell) to tip the driver immediately separate clutch-brake with the hand brake, and then slowly release the brake to the basket.
4. loft lifter safety devices
The code provides that elevated (30m), in addition to the above hoist with low frame hoist safety devices, but also has the following equipment:
(1) limit restrictor. When the basket down before running to meet buffer that can maneuver restrictor, when once the minimum qualifying position, restrictor automatically cut off the power, once stopped declining. When the security check should be action test verification.
(2) buffer. In the lower portion of the shelf of the pit in the buffer when the basket to the rated load and the role of speed to the buffer that should be able to withstand the impact. Buffer type can use spring or rubber, etc.
(3) overload limiters, the main considerations when using elevated elevation is due to run up and down a long distance, time spent transportation personnel often as much as the materials to reduce the running times and overload. This device can reach 90% of the rated load, a beep signal tip drivers load reaches and exceeds the rated loads on lifting power when cut. Safety check should act test validation.

(3) the shelf stable
Upgrade Bay with stable measures in general have two, when building the body is not constructed, using cables with ropes and ground anchor method; when building the body has been formed, you can use wall rods and structural connection methods to guarantee the stability of the shelf.
(1) the provisions of the code, promote rack in ensuring their own strength, in order to guarantee the overall stable wind rope with cables, height can be set in one of the following 20m Group (not less than 4 root), and a height of not less than the 30m following, more than two groups should not be used when 30m cables wind rope method should be used in wall posts, and other rigid measures.
(2) Elevator cables wind rope should force the computation to determine its material specifications, generally choose not to wire rope diameter not 9.3mm.
(3) in accordance with cables wind rope stress conditions, must use the rope (safety factor K = 3.5), does not allow the use of steel, stranded, and other material replacement lead wires.
(4) cables wind rope should be ground into a 45 ° ~ 60 ° angle, tied with ground anchors, not tied to trees, Poles, piles of widget.
(5) to anchor settings appropriate to the force that should normally be conducted using level anchorage, planting outcrops cable fastening rope must be used, shall be reinforced or moreUnit lead wires. When the elevator is below 20m and hard soil, you may use the scaffold tube, and other material into the underground 1.5 ~ 1.7m, side-by-side two, spacing 0.5 ~ 1m, top with Rails and fastener fixed so that the two tube at the same time, stress, work synchronously.
2. in connection with the building structure
(1) selection of wall bars should be elevated rack material of the connection point of the firm, and building structure of the construction programme has embedded (reserved).
(2) wall rods and architectural structure that can be connected to the formation of stable structure, its vertical interval not greater than 9m, and in front of the building must be set 1 group. Shelf height is greater than the top free 6m.
(3) in any case, even the wall rods are not allowed to connect with the scaffold.
(4) wire rope
1. the rope wire number in a pitch in more than 10%, rope rust or surface wear up to 40% and the dead bent, structural deformation cord extrusion, etc., should be scrapped. Break or wear less scrap standards should be reduced in proportion to the load-bearing capacity.
2. rope rope card connection wire rope diameter 7 ~ 16mm, wire card number 3; rope diameter 19 ~ 27mm, wire card no less than four. Wire card spacing for rope diameter of 6 ~ 8 times. Fastening rope card should be the saddle is placed in the lata long rope, U-shaped clasp on the back side of the short rope shall arrange a down a positive.
3. when the rope through the path to avoid crossing protection should be compacted injury. Wire rope used should not be mopping, reducing wear and dirt.

(5) floor unloading platform protection
1. in construction-all floors and elevator connections can pitch their discharge channel, channel side edge protection should be based on Pro provides a protective railing stalls skirting. Channel foot hand tied to pave the way for the guarantee of the safety of transport operations.
2. each layer channel the mouth should set normally closed the door (or protective railing), only when the basket is in place, the door may open floor. Only when all the layers of protective door is closed, the basket can be up and running. Close the door, once before should handle the stopped state. Protective door should confirm stereotypes.
3. lifting rack body surface inlet should pitch their protective canopy, prevent objects against accidents. Protective canopy material should be able to have a defense of ability and strength (5cm plank or equivalent 5cm plank strength of other materials). Protective canopy size appropriate to the frame's width and height (you can press the "fall" RADIUS), protective canopy vertical NET should be hung up on both sides to prevent persons from the side.
(6) basket
1. once the inlet should set a security door, when open gondola landing ground for easy access to materials; basket when you shut down to prevent the lifting platform running material tumble. When the basket when running in place, security door and can be used as temporary edge protection to prevent access to the basket of workers falling accident occurred. Once the emergency door shall be stereotyped gorgeous, simple structure, reliable and secure.
2. loft lifter should adopt hoists for delivering materials hoists in roof can adopt 5cm plank, primarily to prevent workers into the cage in the falling-object operations.
3. material hoist under any circumstances do not permit the officer to the basket, hoists and down.
4. with regard to the prohibition of the basket with a single-wire upgrade issues.
In the preparation of the standards for accreditation at the meeting, a number of areas proposed a single rope used as a hanging basket which leads to a non-secure and cause an accident, should be prohibited to use single rope lift the basket. The general approach is the basket material hoist moving pulley, set on the rope end fixed on the day of the beams, the route around the basket moving pulley, day fixed pulley and then by beam ground fixed pulley to the winch. At this point hoist rope force only to enhance the load of 1/2; and when to use single rope lifting will cable end directly located in the basket, the wire rope stress increased 1 percent. The pulley diameter and winch of power is also to increase, causing unreasonable design; in addition also produces poor stability, particularly when using cables wind rope stable shelf, fabrication and installation of precision, the vast majority of elevator cannot guarantee that the basket import boots and reasonable gaps between the Rails, because once the balance of the loading allows hanging basket running around a collision shelf, increased the shelf wear and instability, if changed to reference the single rope hanging baskets, basket run faster, thereby exacerbating the shelf instability, to use brings insecurities.

(VII) the installation and acceptance
1. the provisions of the standard material hoist used after reinstalling, you must complete before the trial, confirmed to meet the requirements before they can be put into operation.
2. the test method and content
(1) test before preparing test programme, and to lift and carry out a comprehensive check test site, confirm compliance with requirements;
(2) no load test. In no circumstances according to hoist the normal work of the various actions required, including the rise, decline, variable speed, braking, etc, in the whole range to various operating speeds, not less than 3 times. And at the same time test the sensitivity of various safety devices;
(3) rated load test. Once the design provided by load, press the eccentric location by adding 1/6, and then press the no-load test actions repeated not less than 3 times;
(4) test check actions and safety device reliability, there are no abnormalities, the metal structure must not occur permanent deformation, visible cracks, paint peeling, nodes, loose and chatter, overheating and other phenomena;
(5) the Assembly after the test results and test procedure, inspection of the records in accordance with the requirements of fill, finally from participating in the testing of staff signature to confirm that you want.

(8) the shelf
1. the specifications stipulated: "installation and demolition job, according to the field of working conditions and equipment prepared job programmes. On job personnel Division of the low-down, determine the commanding officer, designated security warning zone and care personnel, exclude job disorder. " Material elevator accidents are mostly occurs in the installation and removal process, its main rawDue to the installation, removal is not a reasonable program, job quality is not high, and there is no follow jobs, job conditions, work cannot predict dangerous, causing accidents.
2. the Foundation material hoist shall be construction drawings. Loft lifter basis for calculation; low-bed elevator in design requirements, you can press the pigment tamped, poured concrete, thick 300mm C20.
3. material lifting rack in the vertical deviation after installation, the maximum should not exceed the shelf height 1.5; multiple times when you reinstall, its deviation should not exceed 3 percent, and shall not exceed 200mm.
4. the shelf space with basket, namely, the hanging basket import boots and guide clearance, should control within 5 ~ 10mm.
5. in order to prevent falling-object, in the frame of in vitro side full-height with vertical NET (without asking for a dense mesh) protection. Vertical NET protection should not be screened after drivers.
6. improve rack on install rocker steak bar, you must press the original design called for to ensure loading insurance rope Derrick of job security. Job basket and Derrick cannot be used at the same time.
7. the provisions of the code: "well framed elevator frame, in touch with floor channel openings, to strengthen measures to be taken. "For once in place, workers need to transport materials, frame structure of the original Batten may be removed, to not make the frame section formed local weakened, there should be a temporary hardening measures.
(9) transmission system
1. fixed hoist when not to use trees, Poles, must be ground anchor, front winch should break into two vertical pile prevent winch rotation after the force.
2. reel on the rope should order that cannot produce chaos rope. Wire ropes in order not on reel, cable companies easily squished, rope, cord extrusion cannot continue to use. Practice has proved that the rope in order damage, much larger than the normal use of the wire rope wear and tear.
3. the winch installation location in accordance with the requirements of the stability should meet "from the centre line of the reel to the first distance between pulley and belt grooves should be greater than reel width of 15 times, no grooves should be greater than 20 times. "Requirements. The main purpose of these provisions is to meet the rope can be automatically rolled over in order to avoid wrong stack and out of the drum.
4. the code provides that: "the wheel bearing should be chosen. Pulley blocks and frame (or basket) should be used with the rigid connection, no lead rope, and so flexible connection and use mouth la-plate wheel. "Material hoist is a stationary lifting machinery, is not a temporary lifting of the Derrick, by formal manufacturing design drawings produced a technology requirements. Some units of the elevator did not duly design, actuator pulley is temporary use pull-rope tied to the shelf, pulley, the operational reliability due to wear and caused fastening and connection is not stable, pulley instability rope running chatter is unsafe. You should use the bearing pulley bolt and fixed, not only the rope run reliable and easy to maintain.
Pulleys should frequently check and found that the flange wear bias should be renovated, flange damage timely replacement.
5. when the winch set location cannot guarantee the rope-line on the Web, you should install rope devices and prevent the rope reel ends flange beyond safety.
6. the specifications stipulated: "pulley block pulley diameter and wire rope diameter ratio: low shelf hoist should not be less than 25; loft lifter shall not be less than 30. "Pulley diameter and wire rope diameter ratio is based on the level of work, the higher the ratio the work level. As a result of the work by wire rope stretched, bent and squeeze, force is more complex, and the rope for bent directly and the pulley diameter, the wheel diameter is small, wire rope bending is large, the bending stress that, in contrast, the ratio of the diameter of the pulley and rope, bending stress or less when the pulley and the ratio of the wire rope diameter enough, you can not take into account the effect of bending, simply press the tension calculation. Considering the Loft lifter days beam position higher impairments in daily maintenance, so the ratio lower frame lift increase, the pulley stable and maintenance cycle can be longer.

(10) contact signal
1. low-bed when hoisting machine use, drivers can clearly see each channel and once inside, you can by all levels of personnel to contact directly with the driver.
2. low-bed elevator use, drivers cannot clearly see each job situation, or cross-cutting jobs at all levels of both construction hoist, you should set up a dedicated signal command personnel, to ensure against misuse.
3. when using indoor wells road do vertical transportation or use of overhead lifting machine driver and each station links must be equipped with communication device. Communication device should be a closed circuit of bi-directional communication system, the driver should be able to hear each station, and be able to speak to each station.

(11) winch operation shed
1. the winch and the driver to open the job should pitch their tents in strong action. Operation shed should rain does not affect the view. When distance operation area near the ceiling should be prevention of combat capabilities.
2. operation shed not only protects the reliable operation of the mechanical equipment, but also for drivers of the operation is not supported by dry Flex have protective effect.

(12) lightning
Temporary power supply specification: well Word frame and gantry and other machinery and equipment, in the adjacent building, structure of lightning protection installations outside the scope of protection, but also in the area of thunderstorms, height, you should install the lightning protection system.
1. scope of protection of a lightning protection system is based on the height of the jieshan Qi, 60 ° angle to the ground into the scope of protection, the scope of the protection, the device may not install lightning protection system.
2. China's vast, different regions, the average number of days of thunderstorms are also different, the number of days of thunderstorm days, the more risk, mechanical equipment installed lightning protection system requirements lower height, when access to electrical specifications achieve the required height, you should install the lightning protection system.
Lightning lightning protection installations include:(Jieshan Qi), down lead and grounding. Lightning rod can be reinforced, its Φ 20 length l = 1 ~ 2m, placed in the top-most frame. Down lead wire, should not be used to prevent oxidation and disconnected. Grounding can be combined with the repeated grounding, the resistance is not greater than 10 Ω.