Electric single-beam bridge crane girder design

A factory workshop and based on the actual need to design a single girder crane with electric hoist, because single Hoist and trolley bridge crane girder is the main part of the design success or failure of the relationship between single girder bridge crane and security, thus girder design based on customer requirements. For the single girder crane with electric hoist from the customers the basic design parameters required: lifting weight Q = 3 t; Hoisting height H = 5 m; The span length L = 16.5 m. Girder cross section the choice of the form of single beam Manual block used electric hoist bridge crane beams as orbit of electric hoist, electric hoist running along the beams of the bottom flange. On the premise of meet the strength, stiffness and stability, small span of only a root i-beam girder, used only for lifting is not more than 50 kn, the span is not more than 11 m. To ensure the overall stability of the main girder and improve its stiffness, girder in the end beam should be set up between corner support, when necessary, set the horizontal truss, main girder and end beam welding connection. Main girder of a long-span steel composite beams or steel plates and beams is adopted to form the composite beams. Girder cross section forms in addition to the rolling or welding wide flange beams, other all use with the inside of the inclined flange beams. For large span should also set the level on the catwalk.

Chain hoists most important aspects of lubrication and maintenance

Lubrication maintenance hoists occupies an important proportion of device management is an important aspect of the hearts of some people may have this question:load chain Why chain hoists require lubrication? Today for everyone to unlock this mystery:
Lubrication in mechanical transmission plays an important role, it can affect the performance of the whole chain  lever hoist  , precision, and life expectancy, since the development of human self-awareness to the motion and friction, wear and lubrication of the close relationship, with the development of modern industry, the more the more devices to the pursuit of a high, high efficiency, energy saving and reliable, which lead to mechanical friction in this portion of the more severe conditions, lubrication at this time was extremely important, and in many cases, a sophisticated technology is the key, lubrication only then is the "refueling method" problem, but also in the master friction, wear, lubrication and laws of nature,manual block in addition to the research and development to enhance lubrication.
After more than a comprehensive analysis of equipment lubrication, I believe you set for the device recognizes the importance of lubrication where, therefore, the opponent pull hoist lubrication from now on.

Chain hoist how to adjust the friction clutch

Adjust friction clutch chain hoist use professional testing equipment to measure the friction torque.hoist equipment The use of on-site maintenance, you can only rely on inspection and operational test to complete the following steps:
1, the upper and lower lid and the need to remove the gear box front cover;
2, the locking washer insurance cleat open, and remove the need to adjust the nut, remove the pressure ring disc spring seat and the platen.
3, the outer friction plate without damage or serious damage, the dirt is left in the top.
4, after removing the clutch gear while checking internal friction plate is broken or badly worn, whether the above dirt.
5, clean friction plate, the dried and polished with gauze Replace.
6, try hanging nut after adjustment is required to the amount set out together from half to 25% overload,wire rope winch followed by tightening the adjusting nut, lifting sensitive operation freely, to reach 1.3 to 1.6 times the amount set out above start to slip.
7, in the no-load lifting process required to hook hit the block hit hard rubber case, when the chain hoist motors continue to run while the hook does not move did not hear any sound, indicating that the protective effect safety clutch, and then semi geese lifting load test to the limit position clutch slip, the amount required test load, containing 25 percent since, after less than three trials before the lock washer insurance cleat locked,manual block and the need to slow down cover installed after adjusting friction clutch.

Concerning the technical specifications of wire rope hoist

CD  wire rope hoist  frequently used as a small lifting equipment technical specifications more stringent Next introduce the details of technical specifications, allowing you to hoist its interior there is a general understanding.
       1, wire rope electric hoist three-phase main circuit rated voltage, rated frequency is 50Hz, the working environment temperature (-25 ~ 40) ℃.
       2, electrical, electronics, buttons, switches and other protection shall comply with GB / T 4942.1 and GB / T 4942.2 in IP54 requirements.
       3, for lifting the molten metal is used, fragile, dangerous items such as wire rope electric hoist,manual hoist lifting mechanism working level should be raised, and to add the necessary safety precautions.
       4, electric hoist temperature insulation resistance value is not less than 1.5MΩ, ground connection resistance value is not greater than 0.1Ω.
       Precise technical specifications for the use of lifting equipment to improve the safety and security of the technical specifications for the wire rope hoist part of the contents,manual block if you have any questions please call the hotline inquiries.

Electric hoist equipment management prevention system

   Strengthen preventive electric hoist equipment management system to reduce accidents, to ensure personal safety and work efficiency
       1, strengthening the electric  hoist and trolley  equipment safety management. For electric hoist and other small mechanical characteristics, should develop detailed safety rules and regulations, management system, ledger to complete. For electric hoist, and other special equipment should be regularly organized professional security inspection, investigation equipment problems, the problems identified should be implemented for the responsible units and persons responsible for coming up with feasible deadline for rectification and reform proposals. Functional departments of the rectification of the implementation, feedback and evaluation.
       2, electric  manual block  machinery and equipment for strengthening safety management practitioners. Strengthen education and training, improve operator safety awareness, safety skills to master, compliance, strict compliance with safety procedures and other safety management system.
       3, to strengthen the security of field personnel operating process management. Operation process safety management is in the process of production maintenance operations, through the process elements, the object element, time elements and spatial elements of system control, eliminating that may arise during the operation of the various dangers and harmful factors, to achieve safe production goals the key is to ensure the safety of the whole operation process specification, and reasonable. Process validation system is to require operators to determine, identify, act as a fixed mode of thinking, that is, in the course of operations are recognized by a certain way of operating, thus avoiding accidents.
       4, to strengthen the mechanical hoist equipment management. From the design, manufacture, installation, maintenance and other aspects of strict control, timely elimination of hazards,load chain to ensure intrinsically safe equipment, through technical means to improve the degree of intrinsic safety equipment; equipment body meet safety technical requirements, safety accessory devices should be complete and effective.

Lifting hooks scrapped relevant standards

Lifting hooks scrapped relevant standards
1, the torsional deformation 超过 is 10 °.
2, after welding the hook when worn.
3, the opening degree of increase in size than the original 15%.
4, the hook surface cracks.
5, the dangerous section or plastically deformed hook neck.
6, the size of the hook shank corrosion is less than 90% of the original size.
7, wear dangerous section of 10% of the original size.
8, when a crack tail root rib.
9, the sheet has lateral deformation of the hook plate,lever hoist when the deformation of the bending radius is greater than 20 times the thickness, the hook must be replaced film.
10, sheet hook up spindle wear 5% of the original size, should be scrapped mandrel.
11, the wear plate wear plate hook up to 50% of the original size,load chain should be scrapped wear plate.
12, the sheet bushing wear hook up to 50% of the original size,manual block the bushing should be scrapped.

Miniature, electric chain hoist operation details

  Mini electric hoist especially for households with high-rise buildings can be easily lifted from the downstairs heavier daily, and for a variety of occasions, small pieces of crane unloading cargo. Simple structure,hoist and trolley easy installation, small size, and single-phase power as a power source, uses a very wide range of this new electric hoists are widely used in machinery manufacturing, electronics, automotive, shipbuilding, workpiece assembly and high-tech industrial zone and other modern industrial production line , assembly line, assembly, logistics, transportation and other occasions. In warehouses, docks, ingredients, hanging baskets and small work space narrower space operations, can show its good quality. Is a fixed column, wall-mounted jib crane best accessory products.
    Electric wire rope hoist with a compact, light weight, small size, easy to operate. Can be installed separately word overhead beam can also be installed in electric or manual single-beam, dual-beam, cantilever, gantry cranes and other use.
    Electric hoist characteristics: high performance electric hoist, stamping steel shell, lightweight and sturdy.wire rope winch High-strength safety hook to withstand impact of accidental overload fracture does not occur, but the gradual deformation. Limit switch: limit switch hanging under the hanging device, the motor automatically stops to prevent the chain beyond, to ensure safety. Lightweight, attractive and durable molded chain bag. Limit switch: limit switch hanging under the hanging device, the motor automatically stops to prevent the chain beyond, to ensure safety. Reverse phase protection devices: special electrical wiring, when the power connection error, the control circuit is inoperative.
    Electric chain hoist operation test before use:
    (A) does pressing button switch "down" button, the operation gourd hanging down until the limit switches, at which point the motor will stop automatically.
    (B) does the press button switch is "on" button until the chain is completely retracted into the chain bag, and the motor stops.
    (C) Check the lifting chain lubrication oil of any ready-made lifting chain lubrication can be used, we recommend that you maintain a small amount of lubricating the chain bag, so that the chain can be immersed in the lubricating oil.
    (D) When the host of the number of pairs of chain hanging chain or chain,manual block is strictly prohibited under the hook from the chain will flip to avoid hazard.
    (E) Check the chain orientation purposes, all welding points should be in the same direction, only the chain at all welding points are in the same line, the operation determined to completely positive.

How to choose and use a sling

1, a sling specifications, selection of the type specifications when choosing a sling, lifting loads must be the size,chain block weight, shape, and ready to adopt the combined effect of the lifting method is used to consider factors included in the calculation, to out of the limits of the work force requirements, work environment, the type of load must be considered. Must select both adequate capacity, but also to meet the proper way to use the length of the sling, if multiple sling used simultaneously lifting the load, you must use the same type of sling; flat sling material can not be influenced by environmental or loading effects. Whether or soft attachment lugs need to be carefully considered in the last paragraph sling and lifting equipment and auxiliary accessories to match.
2, restricting the use of the sling angle when using soft flat sling hanging ears, the minimum length can not be used lug lug less than 3.5-fold and the maximum thickness of the contact portion of the hook and hanging ears activities should not exceed 20 ° angle . When connecting with soft slings and lifting lug appliances, the slings and lifting equipment has been in contact part must be, unless the axial width does not exceed sling 75mm, lifting attachments bending radius must be at least sling 0.75 times the axial width. For example: in the cargo hook sling at least 0.75 times the radius of the axial width of the sling. Fabrics of a width which may be part of the cargo hook radius of influence, cargo hook curvature strongly influence the outcome hinder the width of the fabric balanced role.manual hoist Do not overload slings must be used in the right way coefficient, some way limit the work force may have been given on the label, multiple combinations and vertical slings must not exceed the maximum angle.
3, following a good experience in lifting before the planned start lifting and light lifting operation of the program.
4, lifting, the correct use of sling sling connection correctly in safe mode, placement, connected load, must be placed in a sling so that the load can balance the load on the role of sling width; still can not tie a knot sling suture site or distortion can not be placed on a hook or lifting device, and the upstanding portion sling always placed through away from the load, the hook and the locking point to prevent damage to the label.
5, the use of multiple combinations sling sling precautions multiple combinations limits the assessment of the work force depends on the combination of sling load-bearing symmetry, that is, when lifting, sling branch distribution symmetrical uniform according to the design, with the same vertical angle. 3 combined slings, if the branch is not uniform according to the design of the force, the maximum force on a branch, that branch would be designed to withstand the maximum power point close to the sum of the results of the same composition in the sling 4, if not rigid load , will also be counted. Note: For rigid load, most of which three gravity might be, or even two commitments that support only the remaining balance of rotating rings protect the load
6, when lifting, the protective sling sling away from sharp edges, friction and wear, or whether it is away from the load-lifting equipment, should be appropriate to strengthen and protect the sling portion of sharp edges from damage and wear, the necessary additional strengthen the protection of supplementation is necessary.
7, to ensure that lifting the load balancing in the lifting process, we must adopt a safe way to use slings, can not allow the load to tilt or fall from a sling; must arrange slings and lifting the load's center of gravity directly above the point, Let load balance, stability, if the load center is not under the lifting points, the movement crossed the sling may focus. Dangerous.
8, using the lifting sling way if you use hanging baskets, you can ensure that the load secure,manual block because there is no lock hanging like that kind of locking behavior, and you can flip through the sling from the focus, it is recommended to use together with two slings, sling limbs hanging vertically as much as possible, help to ensure equal load sharing between branches. When the lock hanging flat sling, it should be placed to allow natural angle (120 °) of the state, thus avoiding heat generated due to friction, sling neither by force is powerful position, nor an attempt to create a tight jaws, the correct safe way using a sling hanging double lock. Double lock hanging to ensure safety and prevent the load from sliding off the sling.
9, to ensure the safety of personnel in the lifting process, pay close attention to ensure the safety of personnel, must warn personnel in hazardous conditions, if necessary, to withdraw immediately from the danger zone. Hands or other body parts must be kept away sling, sling to prevent relaxation when hurt.
10, in the lifting process, must be exemplary manner must be exemplary lifting hoisting sling to pick up the slack from the sling taut until the load is gradually raised to a predetermined position, particularly important in hanging baskets or freedom taut friction bear the load.
11, controlling the rotation of the load if the load tends to be tilted down the lifting objects to ensure that the load is constrained to prevent accidental rotation of the load is ensured.
12, to avoid collision rigging, drag, friction, vibration, rigging to prevent damage to the ceiling must be taken to ensure that the load is restrained to prevent accidents and other objects flip or collision. Avoid dragging, pulling or oscillation load, if that will increase the Caucasus with the force. If the rigging to withstand the load, or load on the pressure in the rigging, it is not on the ground or rough surface drag sling.
13, rigging landed When lifting, the load in the case of equality constraints landing.
14, the correct storage sling when the sling after completion of lifting operations must be put back in the proper storage; if no longer in use, must be stored sling in a clean, dry, well-ventilated conditions at room temperature, and put on a shelf, away from heat, can be eroded appearance gas, chemicals, direct sunlight or other strong ultraviolet radiation. Priority storage items, you must check sling occurred in the course of any damage, not the store have been damaged sling. When lifting, the sling pollution by acid diluted with water or with the appropriate storage media in advance is recommended to neutralize. Lifting slings based on the chemical properties of materials and related reference to the recommendation from a supplier, we have already used the product in question is not perhaps be necessary. Sling in use becomes wet, or because of clean reasons, will be hung up to dry naturally.

Lifting optional installation and inspection

1 Selection: Enterprise in the purchase of lifting machinery, the first use of the enterprise scope, work frequently, utilization, nominal weight and other factors into account, select the appropriate requirements of this unit of work level cranes. Under the proposed technical parameters,manual block conduct market research. Suppliers of choice, must be licensed with the special equipment safety professional crane manufacturer. And examine supporting manufacturers of processing equipment, the production of standardized, advanced products, compare and choose affordable, good quality, excellent performance, safety devices, complete lifting machinery. After the arrival of equipment, out of the box to check the acceptance random technical information is complete, random parts, tools, accessories are consistent with the inventory, equipment and accessories for damage, defects, etc., and make unpacking inspection records.
2 Install the choice of units
Crane installation team can choose a qualified manufacturing electric  rope hoist  manufacturers, forming manufacture, installation, commissioning one-stop service model. Installation unit is determined, install the unit before installation to help deal with the special equipment begins the report and check the installation team of construction organization plan, installation of equipment, installation procedures, technical requirements, the installation process concealed work records, self-reports and other compliance requirements . After installing the unit to supervise the installation and operation of a comprehensive self-test, load test, self-test confirmed after passing the reporting agency to install special equipment inspection and acceptance. Acceptance and obtain a "safe use permit" only after put into use. After acceptance, and use of the crane should be random technical information, installation and inspection reports and other relevant technical data archiving. Later in the use of our regular inspection,lever hoist repair, alteration, accident records and other information can also be stored in crane safety technology file.

Lifting Accident Analysis

Crane accidents caused mainly operational factors, equipment and environmental factors.
     1 · Operation main factors:
     (A) lifting improper manner, resulting bundle is not strong decoupling, lifting objects scattered or swinging wounding;
     (2) violation of rules,manual block such as overloading of lifting, work and other people in danger zones caused casualties and damage to the equipment, as well as because drivers do not require the use of weight limit, limit, brakes or do not follow the homing, anchor be caused by overloading, over winch, derailed, tipping and other accidents;
     (3) improper command, incoordination caused by the collision.
     2 · Equipment main factors:
     (1) spreader failure, such as a hook, grab, rope, nets and other damage caused by heavy objects falling;
     (2) lifting equipment control system malfunction or failure of safety devices and cause an accident,hoist equipment such as brake failure caused by heavy impact and pinching;
     (3) members strong enough lead to accidents, such as tower cranes dumping, the reason is tilting tower Ao Lu torque exceeds the stabilizing moment due;
     (4) electrical damage caused by electric shock;
     (5) due to gnaw rails, super wear, or bent derailments caused by overhead cranes and so on.
     3 * Environmental factors are:
     (1) due to lightning, wind gusts, tornadoes, typhoons, earthquakes and other natural disasters caused by strong derailed, collapsed, tipping and other equipment accidents;
     (2) Due to space congestion,wire rope winch clutter caused by collision, extrusion accidents.

Lifting operations precautions and requirements

1, lifting operations must hold special operating permit. Total is greater than 10 tons lifting objects, must apply for "lifting safe operating certificate";
2, lifting the total is greater than 40 tons of objects and works of the main structure, shall prepare lifting construction program. Hanging objects having less than 40 tons,chain block but in complex shape, stiffness is small, large aspect ratio, precision precious, construction conditions special case, Erection plan shall be prepared by the construction authorities and security technology sector review, reported supervisor or Chief Engineer approval before implementation;
3, before performing a variety of lifting operations, should be pre-set security guard at the scene hoisting flags and let someone care, non-construction workers allowed to enter;
4, lifting operations, the night should have adequate lighting, outdoor work encounter snow, rain, fog and winds above 6, you should stop work;
5, lifting operating personnel must be properly dressed labor supplies, wearing helmets shall comply with the provisions of GB2811, HG23014 height operation must comply with the requirements;
6, before lifting operations, respond to lifting equipment,manual hoist wire rope, embrace wind rope, chains, hooks, rigging and other equipment checks must ensure safe and reliable, are not allowed to use sick;
7, lifting operations must be a clear division of their duties in accordance with the provisions of GB5082 contact signal, unified command;
8, prohibit the use of pipes, pipe racks, poles, electrical and mechanical equipment hoisting anchor. Without mobility, the construction sector accounted for examination may not be buildings, structures as an anchor;
9, before lifting operations must run a variety of lifting machinery parts, safety equipment and rigging spreader detailed security checks, lifting equipment, safety devices to be sensitive and reliable. Before lifting crane must try to confirm correct before operation;
10, no person shall accompany heavy lifting or hoisting mechanical lift. In exceptional circumstances, must be followed and landing, reliable safety measures should be taken, and after a scene to approval;
11, flare for lifting operations shall comply with the provisions of HG23011. Hoisting ropes hanging job site,wire rope winch embrace wind rope, tow rope, etc. To avoid contact with wires and keep a safe distance;
12, with the stereotypes lifting machinery such as crawler crane trucks, tire cranes, bridge cranes and other lifting operations carried out, in addition to compliance with this standard, we must also comply with the stereotypes mechanical procedures;
13, lifting operations must be carried out according to specified load lifting, lifting, rigging calculated choose to use, non-overloaded. The lifting heavy objects close to or reach the rated lifting capacity, check brakes, with a low height, short stroke trial suspended after a smooth lift;
14, suspended below the non-stop heavy people, traffic and work;
15, the lifting operations must strictly observe the "ten no hanging" provides that: ① command signal is unknown; ② overload or weight of the object is unknown; ③ external oblique pull heavy lifting; ④ insufficient light, strobe, or a workplace shadow; ⑤ to stand under the weight; ⑥ heavy lifting heavy objects buried in the ground or on a leash lashing connect with other pipelines; ⑦ heavy fastening strong, rope knot killed, unqualified; rigging is not complete ; ⑧ edge blade objects without liner measures; ⑨ weight more heads; ⑩ safety device failure.
16, you must press the "lifting safe operating certificate" reported on the contents of the job, is strictly prohibited alter,manual block lend, "hoisting safe operating certificate", change jobs, and expand the range of operations or transfer operations area;
17, incomplete examination and approval procedures for lifting operations, security measures are not implemented, the operating environment does not meet safety requirements, the commanding officers illegal command, the operating personnel the right to refuse the job.

Trolley operating instructions

Although the monorail is a common tool,wire rope hoist but there are still many people because of the use of improper methods of damage caused by monorail or shortened life. Here for everyone to talk about in detail when using the common issues and considerations for your reference.
1 TROLLEYS non-overload use.
2  hoist and trolley  operation should make the force in bracelet hand chain wheel center plane, shall not be stayed.
3 Trolley cases where the hand pull exception, must not yank, should immediately stop using, check the reason.
4 monorail car gears and track surface regularly filling oil, and check the fasteners loose.
5 TROLLEYS TROLLEYS work is supported beam is, therefore deformation,Manual block distortion, cracking, or do not meet the criteria and have other defects can not be a single-track lane of I-beam.
6 monorail car lifting weights, forbids any person to walk or work under heavy loads.
7 monorail car when lifting heavy focus on the beam within the plane of the web, do not lift.

Control electric chain hoist malfunction how do?

Electric chain hoist can be realized in the car comes with beams up and down and move around, particularly widespread field of use, greatly improving the work efficiency, but in the course inevitably encounter problems, such as malfunctioning of the problem is a recent customer's one,manual block the following summary of experience for your operating electric chain hoist malfunction how to do?

1, due to poor working conditions, causing damage or leakage controller buttons such failures. Focus on routine maintenance, can effectively avoid the problem.
2, resulting in frequent and long-term work limit switch malfunction. No guarantee of security, therefore, basic safety precautions must be prepared to put in place. Shall not be removed or repaired privately.
3, the power supply voltage is too low. Solution:wire rope winch measured voltage value is less than the scale of more than 10% of the supply voltage.
4, check whether the power of the original phase pick the wrong line, such as a wrong phase protection will lead to start and can not be manipulated. Workaround: two phase power line swapped.
5, the control chain hoist circuit fuse burned. Solution: Check and replace fuse accurate
6, the power fuse or no fuse breaker tripped. Solution: Check whether the current demand, replace the appropriate fuse or no fuse switch restarts.
7, the power cord or wire breakage or control circuit connected. Workaround: poor contact wire breakage and repair or replacement.
8, electric  wire rope hoist  motor sound, but did not rotate. Solution: Check the motor phases is accurate - Repair and well insulated action.
9, the emergency switch is pressed. Solution: Make sure the emergency switch is pressed causes.
10, contactor coil circuit. Solution: Replace the contactor
11, the contact is faulty. Workaround: manually operated hoist, electric chain hoist if normal operation, the control coil or wire represents a poor contact, poor position to identify and fix it.
12, as the contactor type selected inappropriate or poor quality, causing the contactor burn adhesions. Does not disconnect and reconnect. Thus, the chain hoist contactor models to choose according to the regulations, in addition to be sure to use quality assurance regular factory.

Tackle the inspection before use

Hoist and trolley is easy to use, versatile, mainly used in factories, mines, agriculture, electricity, construction of production and construction, piers, docks, warehouses, machine installation, cargo lifting, etc. The following will provide you explain  hoist and trolley  before use check:

  (1) strictly in accordance with the nominal weight pulley used to prohibit overloading.
(2) the choice of pulley block sheaves calculated according to the relevant standard groove dimensions should be checked at the same time slot wheel, axle, plywood, hooks and other parts, look for cracks and trauma. If the wear volume of the groove wall 10% of the original thickness, the bottom wear volume of 50% d (match rope diameter) must be scrapped; such as wheel wear up to 5%, severe cracking rim, it must be replaced.
(3) In order to improve the life of wire rope, pulley diameter, generally not less than 17 times the rope diameter,Manual block and is generally used in wire rope sheave groove width than the diameter of 1-2.5mm as appropriate.
(4) in the direction of the force changes in the larger local and high-altitude operations, prohibit the use of hook type, and type pulley rings should be used to prevent decoupling. If they really need to use a hook type, you must also add to its safety device locking hook mouth.