Electric Motors Importance of proper lubrication in electric motors

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1 Electric Motors Importance of proper lubrication in electric motors > > > > Electric motors represent 25% of all rotating equipment in a typical plant Up to 75% of motor failures are bearing related It is estimated that 90-95% of all bearing failures are premature Motor failure can lead to costly downtime

2 Electric Motors Introduction Our experience shows, that electric motors are the most neglected asset in the area of preventive maintenance. Reasons: > Limited know-how about individual motor types > Limited know-how about the different bearings and correct relubrication Better electric motor lubrication results in higher availability, efficiency and a drastic reduction of total operating costs. Industries all over the world are putting more emphasis on the topic of lubrication. perma is seeing a rapid increase in the number of lubrication systems ordered for electric motor bearings. However, most electric motors are still lubricated manually with the motor shut down. ommon Electric Motor Lubrication concerns and resolutions oncerns / hallenges Over / Under lubrication ross contamination of incompatible lubricants hoosing the right lubricant Safety - It is generally recommended that bearings are lubricated while motors are running exposing maintenance personnel to possible danger incidents Hidden bearings. Unlike most applications, bearings cannot be seen Lack of education and competency on proper methods and practice To eliminate the possibility of excess lubricant being forced in motor windings there must be a known exit point for grease injected into bearings Resolution Selection matrix tool to prescribe the precise dosing and intervals losed loop system with visible markings verifying lubricant fill Electric Motors require lubricants with specific characteristics. onsult your motor OEM manuals or your lubricant supplier Automatically lubricated, eliminating danger risks Allows for precise lubrication and eliminates over greasing omprehensive playbook on installation protocol and procedure Use of grease relief valves or drain cups > Re-lubrication, why? 1. Lubricant oxidation causes lubricant quality to deteriorate 2. onsumption of lubricant caused by leaks and evaporation 3. Lubricant is washed out at the lubrication point 4. Lubricant is spun off by moving parts and must be replaced regularly for proper bearing lubrication.

3 Lubrication assessment criteria For electric motor lubrication the following factors are generally assessed in order to develop the lubrication solution: > Motor manufacturer s recommendations > haracteristics of proposed lubricant > Motor speed > Historical lubrication practices > Grease trap / escape port design, access and condition > Duty cycle > Bearing types > Motor orientation (vertical or horizontal) > Service conditions - refer to separate perma Electric Motor Selection Matrix Reading the motor faceplate Gather the following data off the motor faceplate and refer to separate perma Electric Motor Selection Matrix: üframe Size ürpm übearing# The Yellow highlights show example locations of where to find the above information on the motor faceplate Using this information will help determine the proper size lubricator and discharge period. ertain motor manufacturers may use a bearing code rather than the actual bearing number. Please consult the seperate perma Electric Motor Selection Matrix for information. Example of motor face plate location on an electric motor. Shown with perma STAR VA- RIO 120cc units, direct mount. Motor orientation can affect lubrication requirements > It is common to double the grease rate (halve the re-lubrication period) when motors are installed in a vertical orientation > Vertical shafts / bearings have poorer grease retention and poorer distribution of grease

4 > Application Overview: Orientation, Bearing Types and Solutions onfirm and understand bearing types > Smaller motors usually have deep groove ball bearings at both ends > Medium to larger motors usually have a cylindrical roller bearing at the DRIVE End (DE) and a deep groove ball bearing at the NON-DRIVE End Deep groove ball bearing > ylindrical roller bearings have a line of contact between the rolling elements and the races > Deep groove ball bearings have a point contact between the rolling elements and the races > Grease service life is shorter in line contact bearings than in point contact bearings. This is because bearings with line contact apply more stress to grease. Therefore line contact bearings require a higher re-lubrication rate > Lubricator settings are generally selected based on the requirements of the DE bearing ylindrical roller bearing Relief Valve and Drain ups > It is highly recommended, and best practice, that Electric Motors be equipped with an escape route for excess grease that may accumulate in the grease cavity > Use of perma single-point lubricators can greatly reduce the risk of this occurring, but use of a relief valve or drain cup is still recommended Typical Grease Traps & Escape > Grease escape point and collection traps vary greatly and allow for an escape route for any excess lubricant > Grease collection traps must be periodically serviced to prevent overfilling > Drain cups (shown below in 1 oz and 2 oz sizes) are an ideal solution to this issue as they are reusable and in no way mechanically restrict the excess grease flow > Spring-loaded relief valves (B-500; shown below) are an option where space and access limitations make the use of drain cups impractical Grease Inlet Shown with attached FLEX 125 > Free purging bearing designs can freely receive and expel grease allowing adequate fresh grease to be supplied to achieve maximum bearing life B-500 1/8 MNPT (5 lbs) Relief Valve B-475-KIT 1 oz Drain up Kit includes P-111 Pipe Nipple (attached) and B-450 Bushing B-450 1/4 MNPT x 1/8 FNPT Bushing B-485-KIT 2 oz Drain up Kit includes P-111 Pipe Nipple (attached) and B-450 Bushing Drain Shown with attached 1 oz Drain up Kit

5 > Solutions perma lubrication systems for electric motors perma products are used on electric motors all over the world. They guarantee reliable, automatic re-lubrication of motor bearings and seals. perma STAR VARIO Single-point lubrication systems perma STAR VARIO is available in three different sizes (60 cm 3, 120 cm 3 or 250 cm 3 ). They are recommended for the lubrication of different types of bearings requiring different lubricant amounts. perma STAR VARIO operates fully automatic, independent of temperature. The desired discharge period and L size can easily be selected with the push button and are visible on the display. The current operating status is indicated on the display and via the all around LED signal lights (red/green), which are visible from a distance. > Installation and Mounting Decision Making perma Single Point Lubricators can be mounted either directly to an electric motor using our wide options of accessories or when needed due to access and conditions can be remote mounted. To determine best mounting options the following questions should be considered. Remote or Direct? 1. Are there restrictions or obstructions that limit safe and ready access to the lubrication points? 2. Is there limited access to motor while it is in operation? 3. Is there excessive vibration directly at lubrication point? 4. Does the ambient temperature at grease inlet exceed limits for the lubrication system? Answer If yes to any, remote mounting with tube connection would be the best option. Remote mounting Installation examples Main equipment: Electric motor with remote mount 1 perma STAR VARIO 120cc per lubrication point Main equipment: Electric motor with direct mount 1 perma STAR VARIO 60cc per lubrication point

6 Determining Mounting Requirements What is thread size of lubrication point? A vast majority of electric motors have 1/8 NPT threading at grease inlet. There are some exceptions IE: Metric threads. (All Lubricators are ¼ MNPT and require either an adaptor or support) If direct mounting are there any obstructions which would require use of angled fittings and/or extensions? > Direct Mounting on Electric Motors Below are accessories that are commonly used in direct mounting. Reducers, bushings and adaptors are used to adapt from motor grease inlets threading to the lubricator thread. Angles can be used when there are obstructions that do not allow for direct straight mounting to grease inlets. Nipples can be used in conjunction with elbows to avoid obstructions or in cases where the grease inlet is recessed below motor cowling or housing. A-514 Reducer M8x1o x G1/4i A-518 Reducer M10x1o x G1/4i B-101 Adapter 1/4 FNPT x 1/4-28 MNPT, Straight B-400 1/4 NPT oupler Pipe Fitting, Black B-402 1/4 NPT x 2 Pipe Nipple, Black B-404 1/4 NPT x 4 Pipe Nipple, Black B-406 1/4 NPT x 6 Pipe Nipple, Black B-410 1/4 NPT - 45 Elbow, Black B-420 1/4 NPT - 90 Elbow, Black B-450 1/4 NPT x 1/8 NPT Bushing P-112 1/8 NPT oupler P-113 1/8 NPT x 2 Pipe Nipple P-114 1/8 NPT x 4 Pipe Nipple P-115 1/8 NPT - 90 Elbow P-116 1/4 NPT x 1/8 NPT Ball Reducer P-117 1/8 NPT Street - 45 Elbow

7 > Remote Mounting Kits perma has developed specialty remote mounting brackets and kits designed specifically for use with the lubricators. Below are samples of commonly used kits on electric motors. > -Bracket Mounting Kits Double Unit STANDARD DUTY or HEAVY DUTY Assembly Remote KIT Part no. Assembly Remote KIT Part no. Double Unit A-757 -Bracket SD Kit with 6 ft. tubing -Bracket SD Kit with 12 ft. tubing* A-757ASSYSD06 A-757ASSYSD12 Double Unit A-757 -Bracket HD Kit with 6 ft. tubing -Bracket HD Kit with 12 ft. tubing* A-757ASSYHD06 A-757ASSYHD12 * NOT for use with electrochemical lubricators A A B B A B A Number of included accessories depends on unit size of bracket. e.g. A-757 = 2 times each part below A. B-623 3/8"T x 1/4"MNPT Tube onnector B. B-640 3/8" OD Nylon Tubing, Blue D E B-421 included optional, use only if needed D Number of included accessories depends on unit size of bracket. e.g. A-757 = 2 times each part below A. B-401 Pipe Nipple -1/4"NPT lose, Black B. B-550 Manual Purge KIT. B-825 1/4"MNPT x 3/8" swivel hose fitting E. B-100 1/4" FNPT x 1/8" MNPT Reducing Adapter D. B-650 3/8 socket less hose Standard Duty kits are designed for use where ambient conditions are not harsh and there is no need for the manual purge valve option. The Nylon tubing is easily field cut to desired length and the quick connect fittings make for simple and fast connections. E. B-100 1/4" FNPT x 1/8" MNPT Reducing Adapter Heavy Duty Kits are designed for more industrial conditions and harsher environments and include the manual purge valve. Due to it s higher pressure rating the B-650 hose used in the Heavy Duty kits is more suitable for use when incorporating the manual purge valve. Kits do not come pre-assembled. All components are shipped loose. Tubing/Hosing is field cut to shortest usable length and field assembly is required.

8 perma automatic lubrication systems - we meet your needs: > 24 hour operation > Simple installation > Easy, tool-free exchange > Requires little mounting space > Tough systems either battery operated or machine controlled > ustomized supply of fresh lubricants to lubrication points perma is the most trusted partner worldwide for all industries: Global market leader for automatic single-point lubrication systems Largest product range in the market Many well-known satisfied customers Field-tested accessories for every perma lubrication system Product training, expert advice and consultation (please contact your local supplier) Do you have any questions about perma products for electric motors? Please visit our website or contact your local supplier. We will gladly send you our extensive catalog for more detailed information. Electric motor manufacturers generally recommend bearings to be relubricated while motors are running. But, motors are often located in dangerous and difficult to access places. > Work-place safety cannot be guaranteed > High risk of accidents perma USA 2129 enter Park Dr. harlotte, N