AC Motor

2008年8月18日 in AC Motor

AC Motor

ac-motor

AC Motor

Brief Introduction:

A) General:

Y, YKS, YQF, YKK and YR, YRKS, YRQF, YRKK series medium-scale HV 3-phase asynchronous machines(base No. 355-1120mm) are our own designed products after introducing the design and manufacture techniques of 3-phase asynchronous machines of Westinghouse(USA) and ABB(Switzerland). These products were designed with 30 years of design and manufacture experiences of HV 3-phase asynchronous machines and complying with the current national and industry standards. They are with features of energy-saving, low noise, low vibration, reliable and easy to maintenance.
     The power grades, electrical performance and the mounting dimensions of these products are all comply with the standards, that is GB755 Basic Specifications for Rotary Machines, IEC34-1 Ratings and Performance of Rotary Machines and JB/T7593, JB/T7594.
     According to GB4942.1 and IEC34-5 Invasion Protection Class of Rotary Machines, the Protection Classes for these products are IP23, IPW24, IP44 and IP54. The IP23 machines can be modified to IP44(pipe ventilation) on request. Products with other IP class can also be supplied.
     There are three cooling methods for these products, IC01, IC611 and IC81W, according to GB/T1993 and IEC34-6 Cooling of Rotary Machines. Products with other cooling methods can also be supplied.
     The structure and mounting type of these products is IMB3(horizontal with mounting feet), complying with the specifications in GB997 and IEC34-7 Code for Machine Structure and Mounting Type.
     The tables in this catalogue list the specifications and outline dimensions of the above 6kV machines. And that of 3kV can derive from these specifications.

B) Application
These machines can be used to drive general machinery, such as compressors, ventilators, pumps, lathes, handling tools and others. They are typically used in industrial companies, such as mines, machinery factories, petroleum and chemical factories, power factories. The motors used to drive the machinery with high inertia, such as blowers, coal mills, steel bar mills, winches, crackers and belt conveyors, will be provided with relevant specifications when ordering. These specifications act as the base of the special design to ensure the reliability of supplied motors.
Working Conditions:
a) Altitude ≦1000m.
b) Ambient Temp. ≦400C; for rolling bearings >-150C; for sliding bearings >50C; for YKS and YRKS >50C.
c) For YKS and YRKS, coolant temp. at cooler inlet ≦330C and >50C.
d) Maximum month average RH of the most humid month <90% and the month average of lowest temperatures of that month <250C.
e) Power Frequency: 50Hz±1%.
f) Fluctuation of Rated Voltage <5%.
g) Working Duty: S1.

C) Model Symbols
According to GB4831, the model consists of two parts- product symbol and specification symbol.
The following shows the meanings of product symbols.
Y – squirrel cage induction asynchronous motor.
YR- wound asynchronous motor
YKS – enclosed squirrel cage asynchronous motor with air-water cooler
YQF – climate resistant squirrel cage asynchronous
YKK – enclosed squirrel cage asynchronous motor with air-air cooler
YRKS – enclosed wound asynchronous motor with air-water cooler
YRQF – climate resistant wound asynchronous motor
YRKK – enclosed wound asynchronous motor with air-air cooler
D) Structure Description
     Y and YR motors are the basic series products with invasion protection of IP23 and cooling condition of IC01.The protection covers on the top of these motors can be removed and replaced with other covers or coolers to derive different invasion protection classes and cooling conditions, such as YKS(air-water cooling), YQF(climate resistant), YKK(air-air cooling), YRKS, YRQF and YRKK.
     Our motors are box structures, which prevail in world currently. The bases and end caps are all welded by steel plate and with sufficient rigidity and less weight. They are easy to install and to maintain by removing the protection covers.
     The stators of our motors are mounted by outside press method and the windings are made of materials of F insulation class and discharge-resistant materials. Winding ends are all fixed with special operation and secured reliably, and the complete stators are treated with VPI technique. By these, our motors have excellent insulation, damp-resistant and impact-resistant performance.
     The most squirrel cage rotors of these motors are made of cast aluminum and without copper squirrel cage cracking conditions. For the copper squirrel cage rotor, the copper strips are all welded by advanced treatment techniques and specially secured in slots. F insulation class materials are used for wound rotors and treated with VPI method in F class no-solvent insulator.
     Rolling bearings and sliding bearings are used according to the power capacity and rotary speed. The primary invasion protection class is IP44. If the motor has more high IP class, it prevails.
     There is non-shut down lubrication system for the sliding bearings and there has special lubricator filling tools.
     The main connection box has an enclosed structure and an IP54 protection. It is commonly mounted on the right side (view from shaft end) and can be on left side on request. The cable outlet of the connection box can be switched upwards, downwards, leftwards or rightwards. The connection box has a separate PE terminal.
E) Starting of Squirrel Cage Motors(Y, YKS, YQF, YKK series)
The temperature rise and stress of the squirrel cage rotor are computed with advanced technology in design to prevent the motor from premature due to large load when starting.
     The following items shall be checked by users. a) The moment of the rotary part of driven load is less than the responding value (load J) in specifications. b) The terminal voltage of the motor is not less than 85% of rated voltage when starting. c) The characteristics of the counter-torque of the driven load are like pumps or blowers.
Under the above conditions, motors are allowed to start for twice continuously under cool condition or for once under hot condition. Between the two starts, it must be normal stop and the second start shall be activated after one hour.
     If the moment of the driven load will exceed the specified one(load J) or frequent starts will occur or heavy load will be encountered, please contact us prior to order. We will specially designed according your requirements to ensure the reliable starting of motor.