900 Rpm 960 Rpm Ml 240V 1.1kw 1.5HP Single Phase Electric Motor with Gearbox

• Application: Industrial
• Speed: Constant Speed
• Number of Stator: Single-Phase
• Function: Driving
• Casing Protection: Protection Type
• Number of Poles: 4
• Model NO.: ML90S-4 1.5hp
• Starting Mode: y-δ Starting
• Certification: ISO9001, CCC, CE
• Brand: Liyuan
• Housing: Aluminum
• Cover: Aluminum
• Terminal Box: PPO
• Fan: PP
• Fan Cover: A3
• Shaft: C45
• Transport Package: Carton or Plywood
• Trademark: LIYUAN
• Origin: Fuan
• HS Code: 8501400000
• Production Capacity: 50000 Pieces/Year

Product Description

900 rpm 960 rpm ML 240V 1.1kw 1.5HP Single Phase Electric Motor with Gearbox

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Product Description

Model	HP	KW	Currnet	Speed	Eff	Power Factor	Tn	Tst/Tn	Tmax/Tn
ML-90S-4	1.5	1.1	6.76A	1410	74.5%	0.95	7.45	2.2	1.8

 

Company Profile

FAQ

1. Broken shaft
    
   The broken shaft of the motor mostly occurs at the root of the shaft extension and the root of the bearing at the shaft extension end.
    
   If there is a shaft fracture in the motor, macroscopic observation and microscopic analysis of the shaft fracture surface should be carried out to find out the location and cause of the fracture crack, so as to fundamentally suppress the problem.
    
   The fracture surface of the shaft is in the transition fillet area where the bearing is mounted on the shaft (the root of the bearing). If the fracture surface is uniform and perpendicular to the axial direction, there will be no necking and plastic deformation. The fracture fatigue band is obvious, extending from the outer circle to the center, and the final instantaneous fracture area is less than 15% of the axial cross-sectional area.
    
   Mechanical calculation and analysis of motor shaft Since the motor shaft is a stepped shaft, the torque and stress on different stepped sections are different. When the motor is running, the shaft is subjected to the combined action of bending and torsional moments. If a stepped section is subjected to excessive stress, cracks and fractures may first occur at the transition arc of the stepped section. Therefore, find out the dangerous section of the motor shaft for stress. It is important to determine the cause of shaft fracture.
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   Reasons for motor shaft fracture
    
   The fracture of the motor shaft is the result of a combination of factors. Here are some of the most common reasons:
    
   1. Manufacturing potential quality problems. The fracture form of the motor shaft is a low-stress rotating bending fatigue fracture. The root cause is that there are defects in the production and processing of the motor shaft, such as no process control requirements for the shoulder transition fillet, no heat treatment after welding, and super-high inclusions in the surfacing layer, resulting in The stress concentration of the shoulder fillet causes fatigue cracking under the action of the rotating bending moment, which eventually leads to the fracture of the motor shaft.
    
   2, the installation problem. If the belt pulley is used for transmission, the tension force of the belt is too large (greater than the value suggested by the belt manufacturer), which increases the load on the motor shaft, which is a contributing factor to the breakage of the motor shaft. If the motor installed by the coupling cannot ensure the coaxiality of the motor and the axis of the equipment, it will also lead to fatigue fracture of the shaft.
    
   3. The web shaft is broken. Excluding installation factors, irregular cracks often appear on the web shaft at the welding position of the web. Most motor manufacturers solve the problem of this type of shaft through the annealing process and at both ends of the web and the spindle connection, by machining stress grooves. Broken shaft problem.
    
   Channeling
    
   No matter what motor should not move the shaft at any time, a little amount of movement has little effect on the motor itself. If the amount of movement is large to a certain extent, the current will increase, the temperature of the motor will increase, and the mechanical impact will increase. Specific issues such as affecting other devices.
    
   Analysis of the causes of motor shaft shifting
    
   1. The mechanical center is inconsistent with the magnetic field center. When the motor is running, the rotor will be positioned at the center of the magnetic field, and there is a mechanical center between the rotor main shaft and the two bearings (that is, the position where the distance between the shoulders at both ends of the motor rotor and the bearing is equal). There may be inconsistencies between these two centers. If the distance between the shaft shoulders is adjusted based on the mechanical center during installation, when the motor is started, the rotor will be automatically positioned at the center of the magnetic field, and the axial movement of the motor shaft will destroy the original installation. the axial distance. When this deviation is not large, for the gear coupling, it can be compensated by the reserved axial clearance of the inner and outer gear sleeves; if it exceeds the reserved axial clearance of the coupling, the coupling and the driven shaft will be affected by An external force is applied to one axis, causing the end face of the component to rub, resulting in harmful effects such as heat generation.
    
   2. For the sliding bearing motor, there is an error when the rotating shaft is centered according to the coupling. The misalignment of the shaft in the bearing will add a large additional torque to the bearing. Since the rotor of the motor can move back and forth in the axial direction within a certain range, when the center of the shaft system is not aligned, the coupling will produce axial separation in a fixed direction. Under the action of the axial component force, the rotor overcomes the magnetic field force and pushes to one side, resulting in dynamic and static friction between the oil blocking shoulder blade of the motor rotor and the babbitt alloy on the outside of the bearing.
    
   3. The lift at both ends of the motor rotor does not meet the requirements. The unreasonable lift of the journals at both ends of the rotor of the motor will cause the rotor of the motor to slide to the end with the small lift against the magnetic field force under the action of the axial component of its own gravity. Therefore, reasonable lift at both ends of the motor shaft is the key to eliminating the axial component force.
    
   The rotor has static deflection due to its own weight, which means that when the rotor is placed horizontally, the two ends or journals will rise upwards. This lift value measured with a precision level is customarily called the rotor lift.
    
   In view of various reasons for the motor shaft shifting, problems should be avoided in the process of motor design, manufacture and installation, and it is also critical to suppress and prevent the occurrence of problems through some necessary means in the actual process.
    
   Select the interference fit for the fit of the shaft and the rotor. If there is movement due to fit problems, most of them are due to problems with the processing size of the shaft, because the inner diameter of the rotor shaft hole is determined by the die, and theoretically, there will be no major problems.
    
   The wave spring washers at both ends of the bearing are not installed, or there is a problem with the quality of the wave spring washers. Some motor operating conditions have relatively strict requirements on the amount of movement of the shaft. Motor manufacturers solve the problem by adding wave spring washers, and some manufacturers add stop rings on the end caps for small motors with sealed bearings.
    
   The axial force generated by the fan, that is, the axial force of the wind on the fan blades when the motor is running, but the resulting turbulence is very small.
    
   The selection of the bearing and the end cover is not suitable, or there is a large gap between the two due to the problem of processing quality.
    
   How to prevent the broken shaft of the motor?
    
   Reducing and eliminating stress points and eliminating external force factors are the principles to prevent shaft breakage. From the analysis of the structural characteristics of the shaft, the sudden change of diameter and the slender shaft of the large-diameter rotor should be avoided from the design stage, and the stress should be removed through necessary measures from the manufacturing process.
    
   (1) Control of machining stress. For motor products, cylindrical blanks are mostly used for processing. Due to the structural characteristics of the shaft, it is basically a stepped structure with thick and thin ends in the middle. The position where the diameter of the shaft changes is the part where the stress is concentrated, so it should be divided into multiple channels. The method of process processing reduces the chance of stress concentration. It is necessary to reduce the processing stress by processing the transition fillet at this position. In the actual machining process, it is possible that the transition fillet is understood as an apparent quality control, and its most substantial role is one of the measures to avoid stress.
    
   (2) Removal of welding stress. For the welding stress, only the shaft with the web is involved, that is, the web of a certain height is welded on the basis of the cylindrical blank to achieve the cooperation with the rotor core. There are many fractures in this type of shaft.
    
   According to the welding execution process, it is divided into instantaneous stress and residual stress of welding, and the welding stress of the control web shaft should be controlled from the welding process and the finished product. In order to reduce the instantaneous stress of welding, the preheating of the shaft before welding is particularly important. In order to reduce the welding residual stress of the shaft, the welded shaft should be subjected to stress relief treatment. The treatment method can be ultrasonic vibration or heating. way to proceed.
    
   The fission of the welding shaft generally occurs at the butt end of the web and the main shaft, and some are longitudinal cracks that extend inward along the direction of the weld. The early stage of such problems is the severe noise and sweeping of the motor, and the cracks are not serious. It is difficult to check the situation, and it needs to be analyzed and judged by the method of radial runout detection.
    
   (3) Motor installation and transmission control. For motors with relatively large power, it is not recommended to use pulley transmission, because this transmission method will cause the shaft of the motor to be subjected to bending moments, which will cause the shaft to break in severe cases.
          
   The requirements in this regard are stipulated in the product technical conditions of the motor, and are also described in the product operation and maintenance instructions of the standard motor manufacturer, but the requirements may not be implemented in specific use. For motors that must be driven by pulleys, especially motors with relatively large specifications, it is recommended to use cylindrical roller bearings at the drive end.
    
   (4) The reliability of the motor installation benchmark. From the actual use, it can be found that some motor installation benchmarks are not directly in contact with the ground, but are raised to a height by means of a frame. In this case, special attention should be paid to the reliability of the benchmark. If the benchmark is out of balance, it is very easy to cause The shaft fracture problem occurs due to the positional relationship between the motor and the dragging device.
    
   (5) Daily monitoring and measurement during motor operation. During the operation of the motor, the placement of the motor itself and the relative position of the equipment have a great impact on the quality of operation. Periodic inspections and daily monitoring should be used to find problems and correct them to prevent quality accidents.