The analysis of the causes of leakage of transformer oil - to solve the problem of oil leakage

1,product improvement:for porcelain set of oil leakage at the bottom of the transformer,because of the maintenance condition,can only be replaced with a new transformer.Will oil leakage transformer to return factory repair,and ask the manufacturer to improve the sealing structure.The transformer oil leakage,timely communication with the manufacturer recommended manufacturers choose better quality rubber gasket,explore the possibility of using new material packing.2,the process of making the maintenance plan for now a terminal oil leakage transformer by Taiwan to asynchronous motor apply for stop service,timely deal with oil leakage.For found no oil leakage transformer maintenance plan,equipment stop service with a porcelain on the surface of the flange bolt fastening.During the overhaul of random overhaul of main transformer transformer terminal change once motor parts a gasket.3,the pass of maintenance process:in the transformer overhaul the repair technology to the health of equipment has a decisive role.

Pass of maintenance technique,in case for overhaul quality caused by defective equipment:such as wiring fever caused by poor contact,non-standard oil caused by false oil level and test unqualified,the bad weather caused insulation be affected with damp be affected with damp.In the concrete work of this www.facebook.com/dongfeng.motor notice.In particular,when a terminal assembly,porcelain set of inner arc bakelite pad should be paid attention to in installation surface must with porcelain set wall stick take,otherwise will lead to a terminal external after fastening flange surface tilt,make rubber gasket cannot even tighten and easy broken porcelain bushing.4,product selection,now know,a growing number of oil-immersed transformer is replaced by SF6 transformers,the use of SF6 transformer can reduce many electrical motor 24v make the daily maintenance work,the only worry is leak problem,now understand of SF6 transformer leakage rate in a few parts per thousand,but now the oil-immersed transformer oil leakage rate in percentage more than a dozen,even a few decades.I think that using SF6 transformers very much worth considering.

The structure of three phase asynchronous motor

A,the classification of the three-phase asynchronous motor:Classification:according to the rotor structure Category:squirrel-cage motor and wound rotor motor According to the protection type Categories:open (IP11),protected (IP22 and IP23),closed (IP44),explosion-proof According to the ventilation cooling way Categories:self-cooled,since fan cooled,he fan cooled,pipes,ventilated According to ac synchronous motor the installation structure Categories:horizontal,vertical foot,flange According to the grades of insulation Category:E,B,F,H, According to the work quota Category:continuous,intermittent,intermittent Description:Open (IP11) :cheaper price,the best cooling conditions,due to the rotor windings and exposed to air,can only be used for dry,little dust and no corrosive and explosive gas environment.Protected (IP22 and IP23) :ventilation cooling condition is good,also can prevent the water droplets and iron filings,sundry fall into motor internal,applies only to a few dry and dust and no corrosive and explosive gas environment.Enclosed (IP44) :suitable for damp,dusty,vulnerable to wind and rain erosion,corrosive gases,such as the poor working rotor and stator environment,the most common applications.

Second,the structure of the three-phase asynchronous motor (a) of the stator (static) 1,the stator core Part of motor magnetic circuit,and placed on the stator winding.Structure:the stator iron core by 0.35 ~ 0.5 mm thick surface is commonly insulating layer of silicon steel sheet coining,overlying and become,within the core of the circle has a uniform distribution trough,which embedded in the stator winding.Trough the stator core has the following kinds:Semi-closed type slot:frequency conversion motor efficiency and power factor is higher,but the winding wire and insulation are more difficult.Commonly used in low-voltage motor.Half-open mouth slot:can put molding winding embedded,commonly used in large and medium-sized low-voltage motors.The so-called forming the windings can be treated with insulation in advance and then into the slot.Open rack slot:to put molding winding embedded,insulation method is convenient,mainly used in high voltage motor.2,the stator winding Access is the circuit part of the motor,three-phase alternating current (ac),to produce a rotating magnetic field.Structure:by the three in the space between 120 ° Angle,said arrangement can be connected with the same structure of the winding,the winding of the coil respectively according to certain rule embedded in the stator slot.The main of the stator winding insulation project has the following three:(guarantee between the conductive part of the winding and iron core and reliable insulation and reliable insulation between the winding itself) (1) of insulation:overall between the stator core and stator winding insulation.(2) and white insulation:insulation between each phase of the stator winding.(3) the turn-to-turn insulation:each phase of the stator winding turn-to-turn insulation each wire.

Three-phase asynchronous motor winding fault analysis and processing

Winding is part and parcel of the motors,aging,be affected with damp be affected with

damp,heat,erosion,foreign bodies,intrusion,the impact of the external force can cause damage to

winding,motor overload,under voltage,over voltage,lack of phase operation can also cause winding fault.Winding grounding,short circuit,open circuit fault generally fall into winding,connection errors.Now separately failure phenomena,causes and inspection method.A,winding grounding Winding to close or with insulation casing damage caused by the grounding.1,failure phenomenon Chassis charged,heat control circuit is out of control,winding short circuit,the normal operation of the motor.2,the reason Winding be affected with damp be affected with damp decreased insulation resistance;Motor overload for a long time;The harmful gas corrosion;Metal foreign body into winding internal damage insulation;Rewind stator winding insulation damage when touch the core;Winding end touch end cover frame;Set,rotor friction caused insulation burns;Lead wire insulation damage into the shell;Overvoltage (such as lightning) insulation breakdown.Methods to examine 

3.(1) the method of observation.magnet prices Through visual winding overhang and line slot

insulation observed with and without damage and charred traces,is the pick up location.(2) the

multimeter test.The multimeter low-resistance archives check,reading is very small,it is grounded.(3) megohmmeter.Selected according to different levels of different measuring each group resistance of insulation resistance by megger are,if the reading www.dongfeng-motor.com is zero,then the winding grounding,but the motor insulation be affected with damp be affected with damp or breakdown due to accident,must determine on the basis of experience,generally pointer swing timing in "0" place,its have certain resistance value can be thought of.(4) try to light.If try lights,winding grounding,if found somewhere with a spark or smoke,is the place for winding grounding fault point.If lights dim the insulated grounding breakdown.If rotor and stator the light is not bright,but also showed a spark when the test stick ground,winding yet breakdown,just seriously be affected with damp be affected with damp.Also can use hardwood on the edge of the shell of the seam allowance tapping,to a certain place when a out a bright,when electrical current when broken,it is ground.

(5) current wear burning method.With a regulating transformer,after the power is connected,ground quickly heating and insulation smoke is the pick up location.Should pay special

attention to small motor shall not be more than twice the rated current,no more than half a

minute;Big motor as 20% - 20% of rated current or increasing current,burning to ac motor wind generator the ground just immediately without electricity.(6) packet elimination method.For the pick up location in iron core and burning more severe,in my heart burning loss of copper and iron core melt together.Approach is to put the grounding of one phase winding is divided into two and a half,and so on,finally find out the ground.In addition,there are high voltage testing method,magnetic exploration method,power frequency vibration method,etc.,differ a introduced here.4.The processing method (1) winding drying should be affected with damp be affected with damp cause ground,when cooled to about 60-70 ℃,pour insulating paint again after drying.(2) the end winding insulation damage,in receiving is located in the back of the insulation and painting,dry again.(3) windings to place in the groove,should rewind or replace part windings components.Finally apply different measured by megger,meet the technical requirements.

Motor vibration

Motor through a transmission mechanism is connected to a machine.motor vibration can ac electric motor result in mechanical vibration.mechanical vibration also can make the motor vibration.motor and mechanical transmission part release to start the motor.if eliminate vibration is a mechanical failure.or is the motor vibration.vibration reasons:the diesel generator motor seat is not firm.mechanical part of the motor and the driven generator rotor and stator shaft are different.the motor rotor imbalance.motor shaft bending.belt wheel spindle eccentricity.squirrel cage several breaks.bearing damage.unbalanced electromagnetic system.www.dongfeng-motor.com electric JiSao chamber.