china nucleon crane group: frequency conversion overhead traveling crane

china nucleon crane group: frequency conversion overhead traveling crane: frequency conversion overhead traveling crane Application of  frequency conversion speed regulation in overhead traveling crane First...

frequency conversion overhead traveling crane

Application of frequency conversion speed regulation in overhead traveling crane

First, brief description of the overhead crane

The bridge crane is currently widely used in industrial and mining enterprises in a lifting hoisting equipment. It is generally divided into three basic mechanisms: for lifting heavy lifting mechanism, for lateral movement mechanism for moving heavy objects (i.e. bridge crane car movement organization) and for the longitudinally moving heavy objects (i.e. bridge the crane traveling mechanism)

Where in the hoisting mechanism of the overhead traveling crane is to control the reversing of the three-phase asynchronous motor, and the reel is driven by the coupling and the reducer to raise or lower the wire rope. The bridge crane two mobile agencies, respectively, by controlling the three-phase asynchronous motor positive and negative, through the coupling and reducer drive wheel rotation.

Second, the bridge crane frequency control of the overview

Bridge crane frequency control principle: In the asynchronous motor of the number of pairs of p and slip s of a certain circumstances, only to change the power supply frequency of the asynchronous motor f, can achieve the speed of the asynchronous motor. However, when the power supply frequency f is less than the rated operating frequency of the motor changes, the terminal voltage U ≈ (where: E1-induced electromotive force, f-power supply frequency, w-series turns, k-winding coefficient, φ-motor Of the flux), only to maintain U / f constant, in order to ensure that the motor flux φ unchanged to ensure that the motor performance unchanged. And when the power supply frequency f is greater than the rated operating frequency of the motor, the motor speed exceeds the rated speed, if still maintain U / f constant, the terminal voltage U will exceed the rated motor voltage, which is not allowed, therefore, the rated speed , The power supply voltage should be kept constant and rated, only increase the frequency f of the power supply, the motor flux φ will be reduced, the output torque will also be decreased, while the output power is approximately constant.

Bridge crane frequency control mode is generally used U / f control, vector control and direct torque control. Hoisting mechanism of the crane which uses a closed-loop vector control or closed-loop direct torque control; and mobile institutions generally open-loop U / f control mode or open-loop vector control mode.

Bridge crane frequency control is generally divided into hoisting agencies variable frequency speed control and mobile agencies, mainly by the organization of the inverter motor, inverter, control devices and line protection switches and other components. However, in order to prevent the inverter interference to the outside world and their protection, and improve the accuracy of motor control, generally in the inverter around with AC / DC reactor, the brake unit and braking resistor, filter and transmission card pieces, etc. . Which, according to the use of different overhead crane mechanism, the hoisting mechanism used in the variable frequency motor are equipped with optical rotary encoder to improve speed accuracy and response speed. At the same time control devices using PLC and relay combined to replace the past, the use of AC contactor control, the control system reliability, flexible application, the line is simple, easy to use and low failure rate.
For more details, please contact us via info@nucleoncranegroup.com

- See more at: http://www.nucleoncranegroup.com/frequency-conversion-overhead-traveling-crane.html

320Ton Overhead Crane for Casting

320Ton Overhead Crane for Casting

China Nucleon Crane Group

#Web http://www.nucleoncranegroup.com/double-girder-overhead-crane.html

#Contact Skype:nucleoncranegroup OR Email:info@nucleoncranegroup.com

china nucleon crane group: Electric Hoist Lifting Heavy Load

china nucleon crane group: Electric Hoist Lifting Heavy Load: Electric Hoist Lifting Heavy Load The Reason of Wire Rope Electric Hoist Can not Obliquely Lifting Heavy Load The drawing of electric ...

Electric Hoist Lifting Heavy Load

The Reason of Wire Rope Electric Hoist Can not Obliquely Lifting Heavy Load

The drawing of electric hoist

Wire rope electric hoist can not be inclined hanging heavy objects, why? From the perspective of our physical mechanics!

Junior high school physics class we learned a knowledge point that: If you want to bring a heavy object, are brought him straight up, if the ramp, then the power consumption of more, but also not smooth, in fact, the reason for the wire rope Electric hoist on the same applies.

Lifting heavy objects in the wire rope hoist, we also require a vertical lifting, do not oblique hanging cable, if oblique hanging cable，will not only make heavy objects swing or collide with other objects, but also cause broken rope, Overload, and even heavy objects such as falling, resulting in immeasurable losses. If the wire rope is squeezed in the reel shell or fall outside the pulley, the inclined cable-stayed cable will be squeezed bad; if the weight of the pulled objects, but also the phenomenon of wire rope fracture. This is very dangerous.

A weight of P kg, placed on the ground, such as the vertical lifting, with the same force N or slightly larger than N force, heavy objects can leave the ground. However, such as the use of wire rope ramp (pull S and the ground perpendicular to the line into a α angle), in order to lift heavy objects, the wire rope S will be much greater than the weight of P Caixing. This is why?

According to the law of the decomposition of the force, the tension S can be decomposed into a vertical component force N and a horizontal component F. As can be seen, S> N, because the requirements of N = P, so S> P. That is, the slant crane wire rope tension than the weight of heavy objects, and the larger the angle α hanging angle, S is also greater. Ramp will produce overload, is this truth.

In addition, due to the ramp to produce a horizontal component of force F, when the weight off the ground, F force will drive the weight to the vertical center of gravity swing, if at this time close to the other objects can touch. This is not another important reason for the ramp.

Through the above example analysis, I believe we will be able to understand why the wire rope electric hoist is not inclined hanging ramp, but also to remind you in the use of the user must comply with the procedures for operation.

For more details, please contact us via info@nucleoncranegroup.com

- See more at: http://www.nucleoncranegroup.com/electric-hoist-lifting-heavy-load.html

CD electric hoist-nucleon crane group

CD electric hoist-nucleon crane group

CD electric hoist

CD electric hoist low price, widely used in warehouses

The advantage of the electric hoist made of Nucleon crane group is: easy to operate simple, fast speed, wire rope length can be customized according to customer demand, in order to increase product safety, also set the limit switch, low price, can be widely Used in factory warehouses, logistics, freight and other occasions.

Nucleon wire rope electric hoist with a safe brake device to ensure that the goods in the lifting process of unexpected power failure, can also ensure the safety of lifting material. Electric hoist excellent rope guide to solve the lifting process of swinging items. With the road and electric sports car to meet your needs on different occasions Nucleon imported chain electric hoist all imported from Taiwan and Japan, the products are in accordance with international standards of production, electric chain hoist body with a chain frame to ensure that the chain in the rise And when the chain will not be the case of the chain of cards will not lead to the work of the interruption or cited the situation occurred Nucleon lifting welcome new and old customers to negotiate to buy.

Nucleon lifting electric wire rope hoist mainly CD1 and MD type two. They have different characteristics, CD-type wire rope hoist to enhance speed, up to 8 meters per minute. CD-type electric hoist using high-quality braking system to ensure that even if the power lifting process will not cause security incidents. CD electric hoist with aluminum radiator, heat dissipation is particularly good, it can withstand long hours of high-intensity work, upper and lower limit switch to ensure that the rope does not reverse the situation.

The use of wire rope electric hoist can greatly improve the production efficiency and reduce labor, help to improve the company’s costs and improve corporate income.

- See more at: http://www.nucleoncranegroup.com/cd-electric-hoist.html

Installation of 320Ton Overhead Crane

Installation of 320Ton Overhead Crane