Malabar Carbons Pvt. Ltd.

Adityapur, Jamshedpur, Jharkhand

A slip ring is an electromechanical device that allows the transmission of power and electrical signals from a stationary to a rotating structure. A slip ring can be used in any electromechanical system that requires unrestrained, intermittent or continuous rotation while transmitting power and / or data. It can improve mechanical performance, simplify system operation and eliminate damage-prone wires dangling from movable joints. Also called rotary electrical interfaces, rotating electrical connectors, collectors, swivels, or electrical rotary joints, these rings are commonly found in slip ring motors, electrical generators for alternating current (AC) systems and alternators and in packaging machinery, cable reels, and wind turbines. They can be used on any rotating object to transfer power, control circuits, or analog or digital signals including data such as those found on aerodrome beacons, rotating tanks, power shovels, radio telescopes or heliostats. Trouble Shooting- Commercial slip rings should have an optional seal that protects them from dust and splashes. They should not be immersed in water. If a unit is going to be subjected to wash downs, the slip ring should be enclosed in a protective housing.

Carbon graphite bushes are used where the temperature is more than 400° F. It is mostly suited where there is corrosive environment, locations inaccessible for thermal lubrication, dusty environment where bearings & lubricants would require protection. In the recent times Graphite Carbon Bushes have replaced conventional bushes and rings of steel for a variety of reasons – Graphite Bushes are Self Lubricating and is ideal where thermal lubricants cannot be used. High temperature is not a problem. Machining on CNC machine to a tolerance of 0.013 mm is easily done. It protects the bearings and provides a smooth surface and has a polishing effect. Very low co-efficient of friction and thermal expansion Resistance to corrosion, chemicals and oxidation Low density Excellent thermal shock Good mechanical strength High temperature resistance  Trouble Shooting- Grit- Any kind of impurities like sand, granules, water particles, oil, dust present in the air can cause breakage of bushes Prolonged idle time/inactivity- Inactivity results in migration of the lubricants away from the bearing area and eventually hardens the lube that remains. When the machine is restarted metal to metal contact occurs immediately which causes breakage of bushes Frequent starts & stops can lead to dry running. If a bearing is immobile for a month or more, the bushes break due to absence of lubricating activity Vibration- even moderate vibration can shorten bearing life Corrosives & large loads can lower bearing lubrication Improper/Misalignment – Prevents smooth action of bearings and can cause burrows on the shaft or on the bearings in a matter of months Solutions used in pulp mills can turn perfectly good steel parts, self lubricated bushings into pitted relics in a very short period. Fluids, semi-fluids passing through pumps and mixers can dissolve bearing lubricants 

A carbon brush is a device for maintaining electrical contact from a static to a rotating part in a motor or generator, a moving surface such as a commutator or a slipring, ensures a spark-free commutation and performs the following critical functions- •    Deliver or collect electric current from rotating part of a machine •    Perform the duty of commutation i.e. changing the direction of the flow of current •    Keep the commutator or slipring surface clean & smooth with a protective film of copper & carbon graphite to maintain good contact without excessive wear. Carbon brushes have been used for a long period of time and are preferred due to their excellent properties like good electrical & thermal conductivity and high temperature resistance which make it a highly suitable material for current transmission in rotating electrical machines.  They are widely used in the automotive industry, iron & steel industry, cement plants, paper mills, domestic appliances, generators & motors of the railways.  A carbon brush can be made of one or more carbon blocks and equipped with one or more shunts / terminals. Trouble Shooting - 1.    Over time, the abrasion caused by the moving parts will mean that the brushes will need to be replaced. 2.    It's normal for small sparks to appear when the brushes rub against the motor’s armature, but excessive sparking could mean you need new brushes. 3.    Hardness does not have a direct effect on brush life or brush wear. If the commutators are out of round or have high spots, a harder brush will actually have a tendency to bounce more and leave the commutator surface, potentially causing greater problems than before. Light loads, light spring force and poor commutator conditions are the usual causes of rapid brush wear. 4.    Grooving occurs when there is poor electrical contact, resulting in a high resistance at the brush face with the ring or commutator. This may be due to roughness on the surface or vibration. 

The brush-holder is a mechanical part which is essential to the good operation of the motor. It is necessary to make regular checks on the quality of the pressure system as this is under stress during operation. We manufacture a wide range of high quality & affordable brush holders designed for use with our carbon brushes for improved performance in motors and generators. Our comprehensive range of quality brush holders are used in motors and generators for steel processing, mining, power generation, traction and a wide range of general industrial applications.