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目前显示的是 2017的博文

Cause analysis of the damage of electric hoist rope

Electric drum occurs  electric chain block hoist  rope breaking phenomenon after the replacement of the drum for a short time, although the rope guide device is vulnerable parts, but in addition, there is an unexplained collapse. Rope guide specifications: unless calibration, can generally be divided into for cast steel and for cast iron, the steel drum rope guide for the lifting height above 12 meters with smaller diameter, cast iron drum rope guide for lifting height below 12 meters with large diameter. After the replacement of the drum of the  electric wire rope hoist  is not the original component, it may lead to the uneven force of the guide rope, and may be because of the installation procedure or the components do not match.  WOKAITE  recommends you, if parts damaged, must try to contact the buyer at the time of the original components. The maintenance of explosion proof hoist should be carried out in accordance with GB3836.13, the danger zone rope and roller movement is al

Working level of overhead gantry crane

Overhead gantry crane  installation site and the work conditions is vary greatly, the use of lifting capacity and working frequency are also different. In order to use the crane economically and reasonably, it is necessary to choose the appropriate working level according to the working condition of the crane. The working level of the bridge crane is divided into A1 ~ A8, according to the level of the crane and the load state, that is, according to the frequency and load degree of the crane through the calculation to determine. The crane has a certain number of working cycles during its useful life. A working cycle of a  travelling gantry crane  is to start the process of loading the goods from the beginning to the next. The total number of working cycles represent the utilization of cranes. In order to facilitate the calculation, the total number of working cycles can be divided into 10 categories. 200-400 ton heavy duty travelling  overhead gantry crane for sale

Overhead gantry crane lifting instructions

The overhead crane in workshop should not use mechanical lifting, because the top of the rail is close to the bottom chord of roof truss, in addition, the volume and weight of the heavy duty gantry crane are large. Small and medium sized overhead travelling gantry crane used single mast upright integral hoisting, which can improve work efficiency, shorten the construction period, reduce high-altitude operations, the construction procedures are as follows. Erecting mast 1.The height of the mast The maximum height of the mast is the height from the ground to the roof, minus the operating space between the top of the mast to the roof panel and the height of the sleeper. Minimum height should meet the needs of lifting height. 2.Mast position Since the mast is to be erected at the center of gravity of the travelling gantry crane between the two main girders of the trolley, the trolley must be biased, and the mast should also deviate from the centre line of the plant. The deviatio

Internal structure and function of explosion proof electric hoist

1.Tap: For the need of power grid operation of the explosion proof electric hoist, the general transformer high voltage side has the tap, can not fully guarantee the synchronous switching of tap changer, so the load voltage transformer can not be parallel operation. 2.Voltage transformer: the primary winding turns more than N1, the secondary winding turns less than N2, equivalent to a step-down transformer. When PT is working, the primary winding and the secondary winding are respectively connected with the voltage loop of the primary circuit and the two control loop in parallel. So if the secondary winding short circuit, it will lead to a very large two side current. 3.Hand cart / drawer: hand cart and drawer are part of the high voltage switch cabinet and low voltage switch cabinet. They are basically the same with the fixed switch cabinet, the main difference is the convenience of maintenance and repair. WOKAITE explosion proof electric hoist Explosive-proof grade:Ex de IIB T

The difference between rotary hook and chain hoist block

Recently there are some customers inquiry  chain hoist block , but is not very clear described by the customer, and after communicating with customer patiently, we understand what customers want is the rotary hook on the  manual hoist . About the doubts about the rotating hook and chain hoist block, following by WOKAITE explains the difference of the rotary hook and the manual chain fall for you. The lever hoist is used for guiding the user to operate the gourd from any angle, so as to avoid the operation standard of the ordinary  chain pully block  which can not be oblique pulled, and leading to the user work in the dangerous area. The rotary hook relates to the internal design of the lifting hook of an arbitrary rotation angle when lifting heavy objects. For example, in the hoist lifting weights, sometimes the hook opening towards the west, and we tied rope weight is in the direction of east-west, then if the hook can not rotate, and the lifted goods is heavy, it will be very trou

How to deal with 3 ton electric chain hoist motor overheating

Any machine has the cycle and time of operation, is not suitable for a long time continuous operation. Long time operation will cause mechanical damage and even accidents, but in general if the 3 ton electric chain hoist surface temperature is too high, we need to check what is the reason. Firstly to check whether it is because the electric hoist weight is too large, beyond the 3 ton electric chain hoist rated weight. Overweight operation will make the motor over heating, overload for a long time will cause irreparable damage to the electric chain hoists for sale.  Electric hoist motor  is not overloaded, but still heating, should check whether the motor bearing damaged; Should also check whether the motor Work according to regulations, which is one of the reasons causing the motor heating. When the electric hoist motor is running, brake clearance is too small, not completely disengaged, causing great friction, while the frictional heating is also equivalent to the additional load

Lifting height of overhead gantry crane

Lifting height is the vertical distance from the ground to the highest lifting position. If the extraction device needs to fall to the below ground to work, the drop depth is the vertical distance between the location from the ground to the lowest position of the device. At this time, the total lifting height is the sum of the height above the ground and the depth below the ground. The lifting height is chosen according to the operating requirements. Overhead gantry crane will generally limit the lift height to less than 20m. Because if more than 20m, it is necessary to use the special wire rope winding on the hoisting mechanism, or increase the size of the drum, so that the crane trolley layout is difficult, and increase the size of the crane limit. To the crane for loading operation, when determine the lifting height, should also consider the attachment of the spreader and the height of the vehicle, in order to ensure the crane can load the items of maximum height into the vehicl

Main motor dismounting method of electric hoist

The main components of the  single girder EOT crane  is the electric hoist. electric single girder crane has total six movement, while the electric hoist accounted for four, and the main motor to control the upper and lower movement of the electric hoist, so can be seen that the electric hoist is important in the electric single beam crane.The main  overhead crane motor  of the 5 tons rated lifting weight of single girder crane is 7.5KW , the improper use in the long-term use will sometimes damage the main motor, such as outdoor running without rainproof causing the motor short circuit; such as lack phase operation causing the motor burned; and such as motor wear causing rotor bearing damage and so on. In this case, we need to replace or remove the motor, how to remove the main motor of the  electric cable hoist  hanging on the crane? The steps are as follows: 1.Preparation work, scaffolding or ladders, two  lever hoists , other related tools; 2.After preparation, firstly cut off th

Fetching device for double girder bridge crane

It is great significance for safe production and improvement of production efficiency to select the appropriate fetching device. Due to the double girder bridge crane has a wide variety loading and unloading of objects, there are pieces, scattered and liquid, and so on, their physical properties and characteristics are so different. In order to adapt to load and unload all kinds of goods, commonly used extraction device as grab, electromagnetic sucker, rings, bar, clamp, vacuum suction, hopper, bucket and bearing beam, in addition to the special container spreader and other special tools. Hook is the most widely used device for double girder bridge crane. Grab bucket is mainly used for loading and unloading a large number of bulk materials, but also used to grab the logs. Grab bucket is a kind of automatic fetching device, and its grasping and discharging action is controlled by the driver in the driver’s cab, without the assistance of the auxiliary personnel, which greatly improves

Test procedure before use for the electric chain fall hoist

Before the use of the chain fall hoist will have a simple operation test, the following WOKAITE introduce the operation steps for you in detail: 1.Press the “down” button, drive the chain fall hoist down until the limit position, the motor will automatically stop. 2.Press the “up” button, until the chain is fully retracted into the chain bag, and the motor stops running. 3.Check the lubrication of the load chain. The load chain has already lubricated before delivery, but it’s probably going to dry up in transit, any ready-made lubricating oil can be used to lubricate the lifting chain, we recommend that you keep a small amount of lubricating oil in the chain in the bag, so that the chain can be immersed in the lubricating oil. 4.When the load chain of the  chain electric hoist  is double chain or multi chain, it is strictly prohibited to turn down the lower hook from the chain to avoid danger. 5.Check the direction of the chain, all the welding points should be in the same direction,

How to choose electric hoist motor

The  electric chain hoist  which is most widely used light lifting equipment has the characteristics of repeated short run, frequent lifting, braking and reverse current, overload, multi metal dust and dust operating environment, strong vibration. Therefore, in order to meet the needs of electric hoist, as its main power source of the  crane motor  should have the following characteristics: 1.First, the  electric hoist motor  should have characteristics of stronger intermittent cycle working than the ordinary industrial motor, according to the load duration, the number of contacts and the number of times as an important parameter of motor selection. 2.Electric  crane duty motor  should have better lifting torque and overload capacity. 3.Electric hoist motor due to smaller rotor inertia, greater rotor length diameter ratio, less sight braking. 4.Electric hoist motor should have the maximum safe speed which is several times the rated speed, generally is about 2.5 times the synchronous

Five common problems in operation of CD type electric hoist

1.Can not eliminate the slip phenomenon of trolley. Some repair work that need frequent refueling to make electric trolley rolling on the I-steel track flexibly, in fact as long as put some ZG-3 calcium based grease on the wheel (once every 6 months). Too much oil on the track is easy to adsorb foreign body, leading to wheel slip, affect the normal use of  electric chain block . When the trolley slips, it should be timely to remove the cover on the track, must not add oil to the track. 2.Improper handling of wire rope winding. Wire rope winding is one of the common faults of  electrical chain block , when some maintenance personnel found this kind problem, try to continue to rotate the drum to loosen the wire rope, the result is to caused damage to the wire rope. The right way is to remove the rope guide first, rotate the drum to straighten out the wire rope, and then re install the rope guide. 3.Speed reducer run lack of oil. It will increase noise. When the speed reducer make abnorm

The safety inspection of overhead crane

The safety inspection of  overhead EOT crane  in order to ensure the safe operation, during the operation of the need for a number of safety routine inspection, inspection items and key points are as follows: 1.The lifting height limiter, the travel limit switch and the interlock mechanism are normal, safe and reliable. 2.The main components meet the safety requirements: opening increase less than 15% of the original size, the torsional deformation is less than 10%; the 50% plate hook bushing wear is 5% smaller than the original size, the plate hook spindle wear less than 5%, no peeling, burr, welding. 3.Hook rack and pulley without obvious defects. 4.The wear and corrosion of the surface of the steel wire rope is less than 40% of the diameter of steel wire, broken wire within a twist less than 10% of the total number, no break, no thinning, no core extrusion, no blind angle twisting, no extrusion deformation, no annealing, no burning phenomenon. 5.The clips,clamp and wedge connection

Analysis of the relationship between the components of electric hoist

The use rate of  electric chain block hoist  in china is very high, there are a lot of people do not understand how it works,  WOKAITE  tell you the relationship between the components of electric hoist. First of all, in the process of production, the electric hoist can participate in the specific process operation, its basic structure is similar to that of the ordinary overhead electric hoist, but it also has a special working mechanism or device on the electric hoist. This kind of electric hoist is characterized by frequent use, bad condition and high working level. Four truss type structure is composed of four pieces of plane truss combined into a closed space structure, generally install the platen in the upper horizontal truss surface, light weight, high stiffness, manufacturing is complex and has less production. Truss structure is similar to bias rail box girder, composed of four pieces of steel plate to form a closed structure, in addition to the main web is a external beam, t

The operation of lever hoist

1.Fix the hook of the  lever hoist  with objects reliably , the chain hook hang the heavy item reliably. 2.Weight lifting. The knob is pulled to a position of the label “up”, and then pull the handle reciprocally, the load rise steadily. 3.Drop down weight. Turn the knob to the “down” position, and then pull the handle with the reciprocating, the load rise drop down steadily. 4.Hoist hook position adjustment. When no-load, the knob is pulled to the “0” position, and then rotate the handwheel, the hook chain can be adjusted on the lower position. This is available from the ratchet pawl, hand chain pull easily and quickly adjust the chain hook position. WOKAITE is a professional manufacturer of  3 ton lever chain hoist ,high quality and reasonable price,serve for B2B customers,looking forward to get your inquiry.

How to connect single-phase hoist

Family decoration and other fields often use  single-phase hoist . Let WOKAITE introduce you how to connect  single phase hoist . Three connect lines of the  electric hoist motor , one is public end line, the other two are the winding lines. If it is not divided into main and auxiliary line, the resistance of the two winding lines is as large as the the public end line; if it is divided into main and auxiliary line, the resistance of the main winding line and the public end line is greater than the auxiliary winding and a public end line. In addition, can also be judged based on the number of motor outlet line, if it is divided into main and auxiliary line and is required to be positive, then the number is at least 4. If it is 3, that is, it is not divided into main and auxiliary line.

Safety operation rules of electric hoist chain

In the process of electric hoist maintenance, we found some customers are not operating correctly in the using process, in order to make customers operate electric hoist correctly, following by  WOKAITE  to share how to use  electric chain hoist  safely: 1.Do not operate the electric hoist in explosive gas environment. 2.Stable and accurate button operation is required, do not operate button intermittently and fast. 3.Try to avoid excessive point operation. 4.Make sure that the motor is completely stopped before doing the reverse movement. 5.After  chain electric hoist  operation is completed, please let the controller cable and the hook in vertical static state, not swing or sliding. 6.When lifting, the load must be on average and close to the center in order to ensure the balance, do not lift the weight imbalance. 7.Do not use the  electric chain block hoist  to do the action of dragging the weight laterally. 8.Please do not lift while using the hook to hook the chain which blind

Electric hoist hook introduction

The hook is an important part of the  chain electric hoist , it not only bear the weight of the object, but also bear the impact load of rise and braking, so the hook material mechanical should have high strength and impact toughness. The commonly used hook according to the manufacturing process can be divided into forging hook and plate hook. The forging hook generally forged by 20SiMn, 36Mn2Si and other steel, while plate hook is forged by the multiple pieces of steel plate riveted joint, generally use 20# steel, 16Mn steel. The plate hook is convenient to manufacture, and the load can be uniformly distributed on each steel plate, and the fracture can not happen at the same time, so the reliability of the work is higher than the forging hook. Hook once broken in use process, can cause accidents. Therefore in use must pay attention to check, use a magnifying glass check whether there are cracks. Once found crack, immediately stop using. The hook dangerous section is the section of

Overhead crane operation notes

1.Each  overhead crane  shall be marked with a nominal weight on the obvious place. 2.In the work, don’t allow people on the overhead crane, or transport people or with a hook. 3.No operating license and drink are not allowed to drive crane. 4.The operation must be focused, not talking, smoking, or something else. 5.The trolley needs to be clean; no place equipment, tools, flammable goods, explosive and dangerous goods. 6.Overload are not allowed. 7.Don’t lift any of the following circumstances: (a)Bundling is not strong; (b)Mechanical overload; (c)Unknown signal; (d)Diagonal pulling; (e)Objects buried or frozen in the ground; (f)Someone on the hanging object; (g)Flammable goods, explosive and dangerous goods without safety protection measures; (h)Too full of liquids (i)Wire rope does not meet the safety requirements; (j)Lift mechanism failure. 8.Crane moving on the line with no obstacles, hook or hoist and the bottom surface of the weight, must be lift 2m up above the ground. When mov

Problems caused by improper operation of electric hoist

If the improper operation of electric hoist, will lead to what kind of consequences? The following is a detailed description for you by  WOKAITE . When the electric hoist is hoisting, the method of trolley operation is improper. Electric hoist will make the crane swing and lead to accident. Electric hoist crane hoisting, when the wire rope or chain tensioning should stop,  electric hoist hook  according to the direction of the shake again identify the hook, while lifting workers should check whether the weight hanging in prison; Not lift the electric hoist too fast, the lifting speed can be increased only when the lifting object is out of the obstacle; Objects hoisting by electric hoist should not be too high, generally exceeding 0.5m to the safe passage of the highest is good. When  electrical chain hoist  operation, if the conditions is allowed, it is best to lift off the ground about 0.5m, from the heavy lifting in the electric hoist behind the object, and under the command of

Wear protection of overhead crane

The  overhead EOT crane  active wheel and the speed reducer of the crane are running frequently, and many times of reverse and stop will cause the torque and vibration of the shaft of the reducer to increase, which is easy to cause leakage. The occurrence of such problems, the traditional method to repair machining or welding plating, but both have certain disadvantages: the thermal stress generated by welding and high temperature can not be completely eliminated, prone to bending or fracture; and brush plating limited by the thickness of coating, easy peeling, and the two methods above are repairing metal with metal, can not change the relationship of “hard to fit hard”, in the comprehensive function of the force, will cause wear again.  The latest maintenance methods is mainly use polymer composite materials, which has strong adhesion, and excellent compressive strength performance. Application of polymer materials to repair, not only no welding thermal stress effect, the thickness o

Working principle of electric hoist motor

The DC disc brake of the electric  hoist motor  is mounted on the end cover of the motor shaft. When the  crane duty motor  is connected to the power supply, the electric hoist motor works at the same time. Because of the electromagnetic suction, attracts the armature and the compression spring, brake disc on the armature end cover is disengaged, crane duty motor running. When the power is turned off, the electromagnet electric hoist motor without magnetic force, the spring pushes the armature to the brake disc, the effect of friction torque, braking the motor stop immediately; our factory also produces the corresponding KDA050 dual speed motor.  Electric hoist motor  power supply by the rectifier in the motor junction box, and below 3 kilowatts to 4 kilowatts and above AC220V-DC99V, AC380V-DC170V (special time can also be in accordance with the requirements of the factory design such as (DC24V)),  KDA050  series electric hoist motor , can move quickly after the realization of motor po

Pay attention to six points in the use process of CD1 type electric hoist

1. CD1 type electric cable hoist  often moves on the I-beam track, the stopper must be installed at both ends of the track, to prevent the digression. The best is to assembly reliable elastic buffer or a rubber block at both ends of the wheel axle, the equivalent height of I-steel track, and I-steel track should not put out outside, if you really need to put some with rain proof device. 2.The I-steel track should be installed with grounding wire. If the grounding wire cross-sectional area of I-steel track is too small or not ground, when people contact hook, there is a risk of electric shock accident. So, the I-steel track grounding wire must be well connected, the general specification for flat 4-5mm diameter bare copper wire or a section of not less than 25mm, and should be inspected regularly. 3.Use the limiter and rope guide. The limiter limits the lifting of  electric cable hoist , can prevent the hook to rise too high or too low to crash drum, or down too fast pulling the wi

Electric hoist fault in winter

In the cold winter, the electric hoist operation is very inconvenient,the construction is more difficult especially after the snow,  1 ton electric chain hoists  are often unable to work because of the weather factors, how to deal with it? In general, the electric hoist prone to failure in the motor in winter, because the weather is too cold, easily lead to electric hoist motor can not boot, in this case, do not unload the electric hoist rashly, the basic reason lies in the frozen brake ring. If forcibly boot, easily burn out the motor. So when the electric hoist is unable to boot in winter, must not act rashly, the best solution is to open the motor cover, to pry the motor with a crowbar, which can make it rotate freely, then power up the  electrical chain block , it can work normally.

What is lever hoist

Lever hoist  is a clamp body which through manually pulling the handle, with the lever principle to obtain the linear traction which matched load, acting on the load in the movement, to drive the load operation.  Manual lever chain hoist  has the advantages of compact structure, light weight, small size, easy to carry, labor saving, safe and reliable, long service life, small hand pulling force, small wear on the wire rope and so on. Lever hoist can be used to lift, drag, drop and calibrate. If set the special device, not only can be used for non linear traction operation, but also can easily select the appropriate operating position, or in small tonnage equipment multiplied the load capacity, for the large tonnage load can be used in parallel operation of several machines.