Product Description

Introduction of Electric wire rope hoist

CD/MD model electric wire rope hoist is a kind of big-sized lifting equipment.; It can be mounted on single beam overhead cranes,; gantry cranes,; etc.; With slight modification,; we can also be used as a winch.; It is widely used in factories,; mines,; harbours,; warehouses,; cargo storage area and shops,; essential in raising working efficiency and improving working conditions.;
1.; Trolley electric hoist can be installed with most cranes or hang on the joist steel girder,; lift cargo in straight line or curve line; Fixed electric hoist can be installed on fixed support and lift cargo with vertically or with different angles.;
2.; This series electric hoist applies to industrial enterprise,; mining company,; normal factory,; workshop,; railway,; sea port,; warehouse,; stock ground and so on.; This is the ideal equipment to improve working efficiency and working conditions nowadays.;
Operate Conditions:;
1.; Working temperature:; -20-+40 degree
2.; Work moisture:; <85&percnt;
3.; Elevation:; <1000m
4.; No fire,; no explosive goods,; no corrosion medium.;
5.; Forbidden to lift melting metal,; poisonous,; explosive,; flammable goods.; The working duty is medium,; when the working duty is level up,; the rated lift capacity should be reduced accordingly &lpar;20&percnt; per level);.;

Transmission and Working Principle:;
CD&sol;MD model electric hoists are mainly composed of 3 parts:; Lifting mechanism,; travelling mechanism,; electrical parts.;
Wirerope motor hoist Hoisting &sol;Lifting mechanism
1.; Lifting motor drives rope drum rotating through coupling and hollow shaft of reducer,; which makes the wirerope on the rope drum driving the hook unit up and down.;
2.; If lift height is 6m,; a claw coupling is used to link the motor shaft and input shaft of reducer.;
3.; If lift height is or more than 9m,; intermediate shaft and rigid coupling are added.;
4.; If lift height is or more than 18m,; a carriage is used to enhance the rigidity of intermediate shaft.;
Lifting motor
Lifting motor uses tapered rotor motor with strong staring torque to adapt frequent direct staring in the intermittent work.; CD type hoist uses ZD type single speed motor and MD1 type hoist uses ZDS type double speed motor.; The ratio of ZDS type motor’s constant speed and slow speed is 10:; 1
Speed reducer
Cap 2t hoist uses straight tooth planetary gear reducer and the rest are using helical gear 3 stage reducer.; Gear and shaft are made by alloy steel and high carbon steel and through proper heat treatment to ensure its reliability and service life.; Box body and cover is made of cast iron to ensure hoist’s good damping performance and reliable sealing.;
Wirerope motor hoist Rope Drum
Rope Drum is made of cast iron or seamless steel tube,; using&sol;with the help of spline transferring power.; The sell of rope drum is welded with steel plate.;
Rope drum is the central heart of a hoist.; The upper side is linked with traveling mechanism through equalizing beam.; Both ends are connected with lifting brake and motor respectively.; The lower side works together with hook through wire rope.; Up front of the cover,; limiting stopper guide-rod and heavy punch stop block are installed.;
Lifting hook
Lifting hook is forged with specialized steel.; In the use of trust ball bearing,; lifting hook is linked with sheel through hook beam making lifting hook go slick.; If lift capacity is 5 ton or less than 5 ton,; slide wheel is single.; If lift capacity is 10 ton or more than 10 ton,; slide wheels are double.;
Electric device
The electric device of CD&sol;MD model hoist consists of electric control box,; button switch,; Limiting stopper,; connecting wires and so on.;
The normal operating voltage of button switch is 380V or 36V.; Pressing the correct button can control the hoist through controlling on and off of the relay in the control box,; according to the direction symbols on the button switch.;

Analytical Approaches to Estimating Contact Pressures in Spline Couplings

A spline coupling is a type of mechanical connection between 2 rotating shafts. It consists of 2 parts – a coupler and a coupling. Both parts have teeth which engage and transfer loads. However, spline couplings are typically over-dimensioned, which makes them susceptible to fatigue and static behavior. Wear phenomena can also cause the coupling to fail. For this reason, proper spline coupling design is essential for achieving optimum performance.

Modeling a spline coupling

Spline couplings are becoming increasingly popular in the aerospace industry, but they operate in a slightly misaligned state, causing both vibrations and damage to the contact surfaces. To solve this problem, this article offers analytical approaches for estimating the contact pressures in a spline coupling. Specifically, this article compares analytical approaches with pure numerical approaches to demonstrate the benefits of an analytical approach.
To model a spline coupling, first you create the knowledge base for the spline coupling. The knowledge base includes a large number of possible specification values, which are related to each other. If you modify 1 specification, it may lead to a warning for violating another. To make the design valid, you must create a spline coupling model that meets the specified specification values.
After you have modeled the geometry, you must enter the contact pressures of the 2 spline couplings. Then, you need to determine the position of the pitch circle of the spline. In Figure 2, the centre of the male coupling is superposed to that of the female spline. Then, you need to make sure that the alignment meshing distance of the 2 splines is the same.
Once you have the data you need to create a spline coupling model, you can begin by entering the specifications for the interface design. Once you have this data, you need to choose whether to optimize the internal spline or the external spline. You’ll also need to specify the tooth friction coefficient, which is used to determine the stresses in the spline coupling model 20. You should also enter the pilot clearance, which is the clearance between the tip 186 of a tooth 32 on 1 spline and the feature on the mating spline.
After you have entered the desired specifications for the external spline, you can enter the parameters for the internal spline. For example, you can enter the outer diameter limit 154 of the major snap 54 and the minor snap 56 of the internal spline. The values of these parameters are displayed in color-coded boxes on the Spline Inputs and Configuration GUI screen 80. Once the parameters are entered, you’ll be presented with a geometric representation of the spline coupling model 20.

Creating a spline coupling model 20

The spline coupling model 20 is created by a product model software program 10. The software validates the spline coupling model against a knowledge base of configuration-dependent specification constraints and relationships. This report is then input to the ANSYS stress analyzer program. It lists the spline coupling model 20’s geometric configurations and specification values for each feature. The spline coupling model 20 is automatically recreated every time the configuration or performance specifications of the spline coupling model 20 are modified.
The spline coupling model 20 can be configured using the product model software program 10. A user specifies the axial length of the spline stack, which may be zero, or a fixed length. The user also enters a radial mating face 148, if any, and selects a pilot clearance specification value of 14.5 degrees or 30 degrees.
A user can then use the mouse 110 to modify the spline coupling model 20. The spline coupling knowledge base contains a large number of possible specification values and the spline coupling design rule. If the user tries to change a spline coupling model, the model will show a warning about a violation of another specification. In some cases, the modification may invalidate the design.
In the spline coupling model 20, the user enters additional performance requirement specifications. The user chooses the locations where maximum torque is transferred for the internal and external splines 38 and 40. The maximum torque transfer location is determined by the attachment configuration of the hardware to the shafts. Once this is selected, the user can click “Next” to save the model. A preview of the spline coupling model 20 is displayed.
The model 20 is a representation of a spline coupling. The spline specifications are entered in the order and arrangement as specified on the spline coupling model 20 GUI screen. Once the spline coupling specifications are entered, the product model software program 10 will incorporate them into the spline coupling model 20. This is the last step in spline coupling model creation.

Analysing a spline coupling model 20

An analysis of a spline coupling model consists of inputting its configuration and performance specifications. These specifications may be generated from another computer program. The product model software program 10 then uses its internal knowledge base of configuration dependent specification relationships and constraints to create a valid three-dimensional parametric model 20. This model contains information describing the number and types of spline teeth 32, snaps 34, and shoulder 36.
When you are analysing a spline coupling, the software program 10 will include default values for various specifications. The spline coupling model 20 comprises an internal spline 38 and an external spline 40. Each of the splines includes its own set of parameters, such as its depth, width, length, and radii. The external spline 40 will also contain its own set of parameters, such as its orientation.
Upon selecting these parameters, the software program will perform various analyses on the spline coupling model 20. The software program 10 calculates the nominal and maximal tooth bearing stresses and fatigue life of a spline coupling. It will also determine the difference in torsional windup between an internal and an external spline. The output file from the analysis will be a report file containing model configuration and specification data. The output file may also be used by other computer programs for further analysis.
Once these parameters are set, the user enters the design criteria for the spline coupling model 20. In this step, the user specifies the locations of maximum torque transfer for both the external and internal spline 38. The maximum torque transfer location depends on the configuration of the hardware attached to the shafts. The user may enter up to 4 different performance requirement specifications for each spline.
The results of the analysis show that there are 2 phases of spline coupling. The first phase shows a large increase in stress and vibration. The second phase shows a decline in both stress and vibration levels. The third stage shows a constant meshing force between 300N and 320N. This behavior continues for a longer period of time, until the final stage engages with the surface.

Misalignment of a spline coupling

A study aimed to investigate the position of the resultant contact force in a spline coupling engaging teeth under a steady torque and rotating misalignment. The study used numerical methods based on Finite Element Method (FEM) models. It produced numerical results for nominal conditions and parallel offset misalignment. The study considered 2 levels of misalignment – 0.02 mm and 0.08 mm – with different loading levels.
The results showed that the misalignment between the splines and rotors causes a change in the meshing force of the spline-rotor coupling system. Its dynamics is governed by the meshing force of splines. The meshing force of a misaligned spline coupling is related to the rotor-spline coupling system parameters, the transmitting torque, and the dynamic vibration displacement.
Despite the lack of precise measurements, the misalignment of splines is a common problem. This problem is compounded by the fact that splines usually feature backlash. This backlash is the result of the misaligned spline. The authors analyzed several splines, varying pitch diameters, and length/diameter ratios.
A spline coupling is a two-dimensional mechanical system, which has positive backlash. The spline coupling is comprised of a hub and shaft, and has tip-to-root clearances that are larger than the backlash. A form-clearance is sufficient to prevent tip-to-root fillet contact. The torque on the splines is transmitted via friction.
When a spline coupling is misaligned, a torque-biased thrust force is generated. In such a situation, the force can exceed the torque, causing the component to lose its alignment. The two-way transmission of torque and thrust is modeled analytically in the present study. The analytical approach provides solutions that can be integrated into the design process. So, the next time you are faced with a misaligned spline coupling problem, make sure to use an analytical approach!
In this study, the spline coupling is analyzed under nominal conditions without a parallel offset misalignment. The stiffness values obtained are the percentage difference between the nominal pitch diameter and load application diameter. Moreover, the maximum percentage difference in the measured pitch diameter is 1.60% under a torque of 5000 N*m. The other parameter, the pitch angle, is taken into consideration in the calculation.

China factory 415V Electrical Wire Rope Hoist (CD/MD)     with Good qualityChina factory 415V Electrical Wire Rope Hoist (CD/MD)     with Good quality