Maintenance

Many bearings require periodic maintenance to prevent premature failure, although some such as fluid or magnetic bearings may require little maintenance.

Most bearings in high cycle operations need periodic lubrication and cleaning, and may require adjustment to minimise the effects of wear.

How to measure a bearing

Sometimes you may need to identify a bearing due to general wear and tear. Most bearing references now are laser stamped but these wear and rub off more quickly than the previous method, which was engraved deep in the bearing's metal.

Bearing Sizes

Each bearing has an inside diameter, outside diameter and width diameter in that order. Most bearings are metric in size, but can also be imperial. On our site, each bearing shows its principal dimensions.

d = Inside diameter D = Outside diameter B/T = Width diameter

You can search for a bearing entering this information on the home page in the boxes provided.

Once you have identified the bearing's code some bearings come complete with seals or shields. This is known as the suffix in the bearings reference.

Bearing Example

6205 2RS1C3

The bearing type design that you need is a single row deep groove ball bearing with the following dimensions and suffix.

d = 25mm D = 52mm B/T = 15mm

Result = 6205

The bearing also has a seal either side of the bearing.

2RS1 = 2 Rubber seals 2RSR = 2 Rubber seals DDU = 2 Rubber seals 2Z = 2 Metal shields ZZ = 2 Metal Shields

Result = 6205 2RS1

And the internal clearance being C3 means that the bearing has room for expansion if needed between the races of the bearing, whilst holding the outer ring and moving the inner ring in a radial movement you will detect a little amount of play between the 2 rings. All standard clearance bearings have this movement, it may only be a small amount of movement but is controlled by international standards. C3 means the bearing has more clearance than standard.

For example we may use C3 clearance on bearings where a cold start up application my cause the balls to heat up quickly, the heat needs to go somewhere. Some of the heat gets passed through the outer race to the housing and the inner race to the shaft, this causes expansion which closes up the clearance in the bearing. If you did not allow for this clearance the bearing would not have room for expansion and lead to bearing failure.

C2 = Clearance less than normal C3 = Clearance greater than normal C4 = Clearance greater than C3

Result = 6205 2RS1C3

Unit 9 Clutches

І. Language

Ex.1. Remember the following words and word combinations:

clutch device pulley coupling ensure rigid disengaging clutch coaxial solid bushing key friction clutch jaw clutch breakage transmission train axial clutch rim clutch rim cone clutch disk clutch engage clamp spring band clutch block clutch fixed clutch safety device

зчеплення прилад шків муфта зціплення забезпечувати жорстка муфта позчіплювана муфта сувісний нерухома втулка шпонка, заклинювати, закріплювати фрикційна втулка кулачкова муфта поломка система зубчатих передач осьова муфта обгінна муфта обід, край конусна муфта дискова муфта зачіплювати затискач пружина дискова муфта муфта з розсунутими колодками нерухома муфта запобігаючий прилад

сцепление, муфта сцепления устройство, приспособление шкив муфта сцепления обеспечить жесткая муфта расцепная муфта соосный неразъемная втулка шпонка, заклинивать, закреплять фрикционная втулка кулачковая муфта поломка, разрыв система зубчатых передач осевая муфта обгонная муфта обод, край конусная муфта дисковая муфта зацеплять, включать зажим пружина дисковая муфта муфта с раздвижными колодками постоянная муфта предохранительное устройство

Ex. 2. Read the following international words and guess their meaning.

Difference, permanently, process, operation, motor, friction, stationary, transmission, combine, rotation, to press, cone, disc

Ex. 3 Translate these words into English:

Постійно, передача, давити, тертя, двигун, різноманітність, сполучати, оборот.

Ex. 4 Put these words according to the alphabet and translate:

Clutch, spring, engage, clamp, key, coupling, pulley, device, ensure, rigid, coaxial, breakage, rim.

Ex. 5. Group the words in synonymic pares:

Rigid, to connect, frequently, different, to engage, to join, various, hard, to gear, often, rotation, transmission, revolution, transferring.

Ex. 6. Group the words in antonymic pares:

To divide, movable, to engage, external, to connect, immovable, to disconnect, to unlink, to stop, internal, to start, to combine.

Ex.7. Translate the words paying attention to the prefixes and suffixes :

Station – stationary

Engage – engagement – engaging – disengaging – disengagement

Rigidly – rigidity

Move – movable – immovable – motion

Combine – combination – combining

Connect – connection – disconnect - disconnection

ІІ. Reading

Ex. 8. Read and translate the text A.

Text A