Electric hoist prone to some common failures, before we have introduced, today mainly introduces the reducer oil leakage problem, in order to solve the problem, we must first find out the cause of the problem, the main reasons are the following three points:

1.Between the reducer box and the box cover, the sealing ring is poorly assembled or damaged, should be removed to repair or replace the sealing ring;

2.The reducer connection screw is not tightened, after the shutdown, should tighten the screw.

3.Electric machine sweep: motor shaft support ring wear serious, rotor core displacement, or for other reasons to make the stator core displacement, resulting in the motor conical rotor and stator gap is too small to sweep, the motor is strictly prohibited "sweep", when the sweep occurs, should remove the support ring for a change, adjust the gap between the stator rotor cone surface to make it uniform, or sent to the maintenance factory for repair. Through the analysis of the common faults and treatment of the electric hoist, the electric hoist maintenance personnel know where to start the inspection when dealing with the fault, improve the maintenance efficiency, in addition, but also for the operator to provide on-site methods to deal with the problem.

When installing the electric hoist, you must first choose the installation position. There are several factors to consider:

1. Position of power supply and controller

The electric hoist needs to be connected to the power supply and controller, so it should be selected in a position that is convenient to connect the power supply and controller.

2. Safety factors

The installation location should be away from flammable, explosive and toxic substances, and avoid installation in areas prone to disasters such as strong winds and earthquakes.

3.The transport distance of light and heavy objects

To determine the installation height and position of the electric hoist according to the distance and height of the light and heavy objects that need to be transported.

1.Each newly installed electric hoist, first of all should be idled several times.

2.Before normal use, should be carried out rated load and excess load of 10% dynamic load test, repeated lifting, check its transmission mechanism, electrical part and connection part is normal and reliable.

3.The static load test of 25% of the fixed load, lift the load from the ground about 100mm, suspended for 10 minutes, remove the load to check whether it is normal.

4.In use, it is prohibited to use in an environment that is not allowed to exceed the rated load.

5.It is not allowed to use inclined lifting and horizontal dragging tools, and it is not allowed to lift buried objects.

6.The limiter is to prevent the hook rise and fall beyond the limit position caused by the accident set device, so can not be used as a switch.

7.After the work is finished, pull the main switch of the power supply, cut off the main power supply.

8.Explosion-proof electric hoist should be operated by a special person, the operator should master the relevant explosion-proof operation procedures.

9.The explosion-proof electric hoist should be inspected by specialized personnel at least every ten days, and timely measures should be taken after problems are found, and carefully recorded.

10.Check the explosion-proof motor, explosion-proof control box, explosion-proof limit switch, explosion-proof button switch to remove the explosion-proof shell, first cut off the main power supply, carefully disassemble.

11.When disassembling, the flameproof surface should be strictly protected to prevent collision, resulting in bruises on the flameproof surface and resulting in explosion transmission. When the flameproof shell is cracked and breathable, and the flameproof surface is damaged, it will be scrapped. Install the flameproof shell and tighten each bolt, strictly prohibit loosening.

12.Each mechanism should operate smoothly, hook without jitter, reliable braking, braking slip S should meet the following requirements: S<=v>

13.The steel wire rope used at room temperature at least once a week lubrication, the use of adaptive tools (such as hard brush or smooth clean wood) grease evenly coated on the steel wire rope, winter temperature is low, the grease must be heated.

14.The shift should check whether the wire rope is bent, knotted, whether the rope is prominent or too twisted, whether the surface has signs of torsion, whether the rope strand and individual wire rope are broken, whether the end of the rope is firm, whether the wire rope is clean, whether the lubricating oil is enough.

15.When the explosion-proof electric hoist is working, it is strictly prohibited to suspend the load in the air for a long time to prevent the deformation of the parts.

16.In the use of the process, if found bad fault, should immediately cut off the main power supply.

17.When the explosion-proof electric hoist is used, it should be stopped at the designated location, and the hook should be raised to the position of more than 2M according to the ground.

18.Should ensure that the explosion-proof electric hoist has enough lubricating oil, to ensure that the lubricating oil is clean, should not contain impurities and dirt.

The cylindrical rotor plane brake motor is relative to the conical rotor brake motor, which is mainly composed of a spindle, a cylindrical stator, a cylindrical rotor, a front end cover, a flat electromagnetic disc brake, etc. The electromagnetic disc brake is composed of a flat disc brake disc, a flat disc friction plate, a magnetic yoke, an armature, a brake coil, a rectifier controller, etc. The friction pair is plane contact.

Characteristics of cylindrical rotor plane brake motor

The structure and size of the front end cover, mounting bolt hole division and output shaft of the cylindrical rotor plane brake motor are exactly the same as that of the conical rotor brake motor with the same power. The speed and frame number are also exactly the same as the conical rotor motor, and the two can be directly exchanged without changing the structure and parameters of the electric hoist. However, the cylindrical rotor planar brake motor also has its unique advantages:

(1) Cylindrical stator, cylindrical rotor, processing, manufacturing easy to achieve automation, assembly line production.

(2) No axial movement, intermediate shaft, coupling failure rate is low, long service life.

(3) External DC electromagnetic disc brake, easy to modular production, can achieve fast braking.

(4) Small, beautiful, no rust.

(5) Aluminum shell, good heat dissipation conditions, low temperature rise, high connection duration, can run for a long time.

(6) Energy saving. Using cylindrical motor and DC electromagnetic brake, the motor efficiency is more than 11.5% higher than the conical rotor motor with the same power.

(7) The brake action response is fast, the electric hoist brake slide is small.

(8) The motor starts and brakes smoothly, and the noise is small.

(9) High insulation level and protection level, strong environmental adaptability.

The daily inspection and maintenance of explosion-proof bridge cranes, in addition to complying with the similar inspection items of other bridge cranes, also includes the following main items:

(1) Keep the whole machine and the environment clean. Remove debris and flammable and explosive items in the crane and the environment, technicians should regularly check the concentration of explosive mixtures in the crane operating environment, ensure that the environment has good ventilation and heat dissipation conditions, and control the ambient temperature. During operation, check that the surface temperature of each device must not exceed the specified high temperature.

(2) Each equipment component should be installed without skew and collision phenomenon, no abnormal vibration and noise.

(3) Check the mechanical and electrical equipment, parts of the shell should be free of cracks and damage to the explosion-proof performance of the mechanical deformation. The cable inlet should be sealed reliably, and the unused cable holes should also be sealed.

(4) All kinds of protection, interlocking, detection, alarm, grounding and other devices should be complete, complete and reliable. Whether the explosion-proof luminaire shall maintain the integrity of its explosion-proof structure and protective cover in accordance with the regulations, and the surface temperature of the luminaire shall not exceed the specified value.

(5) When the following situations are found in the operation of the crane, the driver should take emergency measures and stop the machine, and notify the personnel for inspection and treatment in time.

1.The capacitor can not have oil leakage, oil seepage phenomenon.

2.The capacitor can not have oil dirt, dust.

3.The three-phase current should be basically balanced during operation, such as serious imbalance, indicating that the branch fuse is burned, and the corresponding fuse should be replaced in time.

4.The three-phase voltage should be close to the rated value, such as the voltage exceeds the capacitor's own rated voltage (400V) 1.1 times (440V), the electric starting should be withdrawn. The reasons are as follows:

① The capacitor's own heat loss (that is, the dielectric loss) is proportional to the quadratic of the voltage, the voltage increases by 10%, the heat loss increases by 21%, and the capacitor is easy to bulge, even rupture, explosion.

②Whether the capacitor needs to be cast back and the amount of cast back is determined by the power factor of the whole plant and the size of the load. In operation, the power factor should be maintained above 0.9 (referring to the low-voltage side of the charge).

③ For the monthly average power factor of the whole plant, the low-voltage charging should be above 0.9, and the high-voltage charging should be above 0.95, otherwise the fine. The electrician on duty at the end of each month knows what the average power factor of the whole plant is for the month.

④ At noon, evening, and night non-production time, the capacitor should be withdrawn in accordance with it, otherwise it will cause over-compensation, which will unnecessarily increase the transformer current, lead to a rise in voltage, and increase the copper loss of the transformer.

⑤ The capacitor discharge point resistance is reliable, can not be broken, to ensure that the capacitor is automatically discharged after the return, otherwise the capacitor remains a blue charge, the next closing is easy to produce a large current impact, burn the fuse.

After the power failure, the capacitor should automatically exit, otherwise it is easy to produce current impact when the next call comes.

As a light and small lifting equipment, the hand hoist in the operation is also required to have certain skills, and in the use of the hand hoist lifting operation and the hand hoist has a great difference, which is based on the appearance of the two structure and drive mode differences, the following Chenghua manufacturing to take you to understand about the operation of the hand hoist.

First of all, we should be very clear that the drive mode of the lever hoist is to achieve the purpose of lifting by repeatedly pressing the hand-held handle, but in the process of repeated pressing will face such a problem, because the lever hoist is in a suspended state, when pressing the handle will exert a lateral force, and then drive the whole lever hoist to swing together, affecting the lifting operation. It is also very inconvenient to operate, so how to solve this situation?

In fact, the swing of the lever gourd can be solved by some simple changes in the drive, we need to figure out the reason for the swing of the lever gourd, because it does not exert a vertical downward force like the hand pull gourd, and there is no external force in the initial stage of pulling the handle to offset this lateral force, resulting in the swing of the lever gourd. In fact, we can completely limit the lateral swing of the lever hoist.

When operating the lever hoist, we only need to use one hand to press the handle, the other hand to hold the "neck" of the lever hoist, that is, the position below the upper hook, through this way to limit the lateral thrust, so as to maintain the stability of lifting, when the lifting chain is tense, the whole of the lever hoist will be subject to downward load, This force cancels out the lateral thrust, and we can withdraw the "neck" hand.

The stopper device of the electric hoist is composed of a connecting rod, a positioning clip, a rope guide and a stopper. The stopper can avoid the hook being higher than the lifting limit, so as to avoid the failure of punching and breaking the wire rope, and ensure the stability of the equipment. If the installation is wrong, the protection function of the stopper can not be played, then how should we install and debug the stopper of the electric hoist?

1.Loosen the screws on the bumping block, the bumping block is placed on both sides of the rope guide card, and the card can freely push the bumping block to move. Start the motor to start lifting, the pallet pushes the upper bumping block to move, and stops rising when it rises to 15mm-50mm along the lower edge of the drum shell along the upper edge of the hook pulley housing. Press the down button, and when the rope guide moves back about 10mm, stop moving the upper bumping block near the pallet, rotate and tighten the screw.

2.The adjustment method of the lower limit is the same as the adjustment method of the upper limit, but the direction is opposite, but when the hook must be in the low position, more than 3 rings of wire rope are left on the drum. After the adjustment is completed, it is necessary to carry out no-load test run to check whether the installation of the upper and lower limits meets the requirements.

Wire rope electric hoist as a lifting equipment, can be installed in the I-steel as the track of electric single beam, manual single beam, bridge, cantilever and gantry to use, with sports car wire rope electric hoist before installation need to be familiar with the installation environment, construction drawings and related precautions, so that the installation work can be orderly.

1.Installation check

The installation of electric hoist is a high-altitude operation, before installation to check whether the equipment material is in line with the specification, whether the parts are complete, and record the inspection results, carefully study the installation drawings, and understand the installation details.

2.Installation work

(1) When installing the track, the track should first be scattered under the beam, and the separate body and single beam of the electric hoist should be lifted to the appropriate position by the crane.

(2) After laying the track, it is also necessary to make the installation gear, and the gear on the track should be installed before the hoisting crane.

(3) There should be two lifting points when lifting, and the lifting points should be selected at both ends of the bridge.

(4) Lift the car, lift the electric hoist to a suitable position, and install and fix the electric hoist according to the bolt number.

3.Installation and adjustment

After installation, adjust the gap between the wheel and the track, so that the distance between the two is about 3 to 5 mm.

4.installation test

After the adjustment of the wire rope electric hoist is completed, the electric hoist is tested with no-load and dynamic and static load, so that the electric hoist can run normally.

CD, MD type electric hoist is composed of three parts: lifting mechanism, operating mechanism and electric control.

1.Lifting mechanism The lifting mechanism is composed of four devices: drive, brake, transmission and winding. The driving and braking device is a squirrel cage conical brake motor, that is, the rotor and stator of the motor are conical structure, and the brake is also composed of conical brake ring and conical brake wheel. The lifting motor of MD hoist is double electric unit type, and the speed ratio is 1:10 through the gear reduction between the two motors. The transmission device is a four-stage cylindrical gear reducer; The taking device is composed of hook, wire rope, reel, etc.

The overall layout is that the drum is in the middle, one end is a conical brake motor, the other end is a reducer, and the motor shaft is connected with the reducer through the long shaft and the rubber coupling. The drum shell is cylindrical, and there are suspension rows and fixed shapes.

2.The operating mechanism is also known as the hoist car, by the drive, brake, transmission and wheel four devices, the driving brake device is a two-in-one squirrel cage cone brake motor, the brake is a flat brake; The drive gear reducer is an open and closed cylindrical gear drive, and the open gear low speed stage is composed of direct milling teeth on the wheel rim; The wheels are single-rim steel wheels with approximately conical treads.

The running car has manual, chain and electric points.

3.The electric control adopts two sets of standard magnetic starter, one set controls the positive and negative rotation of the lifting motor, that is, rise and fall; A set of control running motor positive and negative rotation, that is, left and right transverse. Operation control is the use of manual button, the operating voltage is 380V, in order to safety some have used a low voltage 36V, in order to prevent chaos, the drum is provided with a rope guide, the rope guide lateral movement with the lifting limit switch action, to control the lifting limit position.