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Thursday, May 7, 2009

Self-aligning Ball Bearings

Self-aligning Ball Bearings
Design
Self-aligning Ball Bearings are particularly suitable for applications where misalignment occurs from errors in mounting or from shaft
deflection.
For applications where the bearing load (particularly axial load) carrying capacity is insufficient, spherical roller bearings, which have
the same self-aligning property, should be used instead.
Cage
Bearings are fitted with pressed steel cage or polyamide cage.
The suffix G of bearing number on the packing surface indicate polyamide cage.
Attention
(1) Maximum permissible misalignment angle is about 2.5º in the 12 and 22 series, and about 3º in the
13 and 23 series under general service conditions. Care must be taken to provide sufficient
clearance between the bearing and surrounding structure when bearing is operating in the full
misaligned condition.
(2) Misaligned bearings will have a tendency to become noisy as speed increases. Due to noise-level
constraints, the practical maximum misalignment may be considerably less than the maximum
misalignment.
(3) The dimension tables show the width of the ball assembly as dimension B1 for larger bore sizes of
Self -aligning Ball Bearings where width of the ball assembly extends beyond the ring width
envelope.
(4) It is difficult to correctly measure the running clearance of bearings with tapered bore after mounting.
Mounting of this type of bearing with tapered bores requires some experience and technique.
(5) The bearings with polyamide cage should be used at less than 120ºC operating temperature.

Deep Groove Ball Bearings

Deep-groove Ball Bearings
Because of their versatility, Single-row, Deep-groove Ball Bearings are the most popular of all the ball bearing types.
NACHI Deep-groove Ball Bearings are available in a wide range of series defined by the JIS(ISO) standard dimension plan and are
also made to meet specialized dimension and configuration requirements. NACHI Deep-groove Ball Bearings are manufactured in
both standard precision grade (ISO Grade 0 - ABEC Grade 1) as well as in high-precision grades.
Table 1 shows common, standard configurations of Single-row Deep-groove Ball Bearings.
Table 2 shows a comparison of general characteristics of seal and shield designs for Single-row, Deep-groove Ball bearings.
Attention
(1) Deep-groove Ball Bearings can sustain radial, axial or composite loads.
However when excessive axial load is applied, please consult with NACHI.
(2) Because sealed or shielded bearings are designed for inner ring rotating applications, the filled grease may leak when they are
used with a high speed outer ring rotating condition.
In such a case, please contact NACHI.
(3) When bearings with contact rubber seals are used in a severe operating condition such as high speed or high temperature, the
filled grease may leak.
In such a case, a design change or another kind of grease is required.
(4) When a bearing is mounted on a shaft (into a housing), force should only be applied to the side face of the inner (outer) ring.
(5) The sealed or shielded bearings should not be washed or heated before mounting.
(6) It should be noted that mounting errors such as misalignment of the bearing rings cause an appreciable increase in noise level.
(7) The bearings must always be subjected to a minimum load to prevent sliding movements occurring between the balls and theraceways.

Bearing Unites

Technical Data

The rubber seal of the cover contacts with the shaft by its two lips, as shown in Fig. 2.2 and 2.3. By filling the groove between the two lips with grease, an excellent sealing effect is obtained and, at the same time, the contacting portions of the lips are lubricated. Furthermore, the groove is so designed that when the shaft is inclined the rubber seal can move in the radial direction.
When bearing units are exposed to splashes of water rather than to dust, a drain hole (5 to 8 mm, 0.2 to 0.3 inches in diameter) is provided at the bottom of the cover, and grease should be applied to the side of the bearing itself instead of into the cover.

2.4 Secure fitting
Fastening the bearing to the shaft is effected by tightening the ball-end set screw, situated on the inner ring. This is a unique bearing feature which prevents loosening, even if the bearing is subjected to intense vibrations and shocks.
2.5 Self-aligning
With the bearing unit, the outer surface of the ball bearing and the inner surface of the housing are spherical, thus this bearing unit has self-aligning characteristic. Any misalignment of axis that may arise from poor workmanship on the shaft or errors in fitting will be properly adjusted.
Fig. 2.3 Cast iron cover
Fig. 2.2 Pressed steel cover
2.6 Higher rated load capacity
The bearing used in the unit is of the same internal construction as those in bearing series 62 and 63, and is capable of accommodating axial load as well as radial load, or composite load. The rated load capacity of this bearing is considerably higher than that of the corresponding self-aligning ball bearings used for standard Plummer blocks.
2.7 Light weight yet strong housing
Housings for bearing units come in various shapes. They consist of either high-grade cast iron, one-piece casting, or of precision finished pressed steel, the latter being lighter in weight. In either case, they are practically designed to combine lightness with maximum strength.
2.8 Easy mounting
The bearing unit is an integrated unit consisting of a bearing and housing. As the bearing is prelubricated at manufacture with the correct amount of high-grade lithium base, it can be mounted on the shaft just as it is. It is sufficient to carry out a short test run after mounting.
2.9 Accurate fitting of the housing
In order to simplify the fitting of the pillow block and flange type bearing units, the housings are provided with a seat for a dowel pin, which may be utilized as needed.
2.10 Bearing replaceability
The bearing used in the bearing unit is replaceable. In the event of bearing failure, a new bearing can be fitted to the existing housing.

Bearing Unites

Bearing Unites, Ball Bearing Unites, UC Type Ball Bearings Unites, Bearing Bracket,

Maintenance free type
The bearing maintenance free bearing unit contains high-grade Lithium-based grease, good for use over a long period, which is ideally suited to sealed-type bearings. Also provided is an excellent sealing device, unique to bearing, which prevents any leakage of grease or penetration of dust and
Water from outside, It is designed so that the rotation of the shaft causes the sealed-in grease to circulate through the inside space,
Effectively providing maximum lubrication, the lubrication effect is maintained over a long period with no need for replenishment of grease. To summarize the advantages of the bearing maintenance free bearing unit:
(1) As an adequate amount of good quality grease is sealed in at the time of manufacture, there is no need for replenishment this means savings in terms of time and maintenance costs.
(2) Since there is no need for any regreasing facilities, such as piping, a more compact design is possible.
(3) The sealed-in design eliminates the possibility of grease leakage, which could lead to stained products.
2.2 Relubricatable type
The bearing relubricatable type bearing unit has an advantage over other similar units being so designed as to permit regreasing even in the case of misalignment of 2° to the right or left. The hole through which the grease fitting is mounted usually causes structural weakening of the housing
However, as a result of extensive testing, in the bearing unit the hole is positioned so as to minimize this adverse effect In addition, the regreasing groove has been designed to minimize weakening of the housing while the bearing maintenance free type bearing unit is satisfactory for use under normal operating conditions indoors, In the following circumstances it is necessary to use the relubricatable type bearing unit:
(1) Cases where the temperature of the bearing rises above
100°c, 212°f: *- normal temperature of up to 200°c, 392°f heat resistant bearing units
(2) Cases where there is excessive dust, but space does not permit using a bearing unit with a cover.
(3) Cases where the bearing unit is constantly exposed to splashes of water or any other liquid, but space does not permit using a bearing unit with a cover.
(4) Cases in which the humidity is very high, and the machine in which the bearing unit is used is run only intermittently
(5) Cases involving a heavy load of which the cr/pr value is about 10 or below, and the speed is 10 rpm or below, or the movement is oscillatory.
(6) Cases where the number of revolutions is relatively high and the noise problem has to be considered; for example, when the bearing is used with the fan of an air conditioner
2.3 Special sealing feature
2.3.1 Standard bearing units
The sealing device of the ball bearing for the bearing unit is a combination of a heat-resistant and oil-proof synthetic rubber seal and a slinger of an exclusive bearing design. The seal, which is fixed in the outer ring, is steel reinforced and its lip, in contact with the inner ring, is designed to minimize frictional torque, the slinger is fixed to the inner ring of the bearing with which it rotates, There is a small clearance between its periphery and the outer ring, there are triangular protrusions on the outside face of the slinger and, as the bearing rotates, these protrusions on the slinger create a flow of air outward from the bearing. In this way, the slinger acts as a fan which keeps dust and water away from the bearing these two types of seals on both sides of the bearing prevent grease leakage, and foreign matter is prevented from entering the bearing from outside,
2.3.2 Bearing units with covers
The bearing unit with a cover consists of a standard bearing unit and an outside covering for extra protection against dust; Special consideration has been given to its design with respect to dust-proofing. Sealing devices are provided in both the bearing and the housing, so that units of this type operate satisfactorily even in such adverse environments as flour mills, steel mills, Foundries, galvanizing plants and chemical plants, where excessive dust is produced and/or liquids are used. They are also eminently suitable for outdoor environments where dust and rain are inevitable, and in heavy industrial
Machinery such as construction and transportation equipment

Wednesday, May 6, 2009

Freewheels Bearings Type, CSK, KK ... 2RS

Description
Type CSK or KK is a sprag type freewheel intefrated into a 62 series ball bearings (execpt sizes 8 and 40). It is bearings supported, delivered grease lubricated and protected against dust of more then 0.3mm. The use of addotional :nylos" type seals os recommended especially when the working temperature exceeds 50C.

Oil bath lubrication is also possible if the original grease is first flushed out using a suitable solvent.

Torque transmission is ensured by a press fit assembly into a rigid outer housing with N6 tolerance and onto a shaft with n6 tolerance. The initial bearing radial clearance is set at C5, and is reduced if using the press fit as specified.
One race may be glued. If both races are to be glued, prefirmance will be reduced or a C3 bearing clearance will be necessary.

Operating Temperature range : -40C to + 100C. Packs upto +120C are acceptable for short periods.
CSK or KK 2RS is 5 mm wider but is equiped with lip seals to be water splash resistant.

BRG # IDXODXW
CSK-12 12X32X10
CSK-15 15X35X11
CSK-17 17X40X12
CSK-20 20X47X14
CSK-25 25X52X15
CSK-30 30X62X16
CSK-35 35X72X17
CSK-40 40X80X22



Freewheels Bearings

Freewgeels are directional couplings, which means that the driving member rotates the driven member in one direction, while automatically disengaging itself from the driven member when the direction of rotation is revrsed.

The two operating states are:
(1) Transmission of torque
(2) Idling (overrunning)

Freewheels may be employed as:

Overrunning Cluch
The freewheels disengages automatically when the dirven member rotates faster than the driving member.

Indexing Clutch
The freewheel allows the conversion if reciprocating motion into rotation movement.

Backstop
The freewheel allows rotation in one direction only. It overruns continuously during operation. The freewheel precents recerse rotation of the drive is disconnected.

Basic Version
Two basic versions are available. The over-running speed determines the selection of the appropriate model.
1. Grip-roller freewheels for low to medium overrunning speeds and for indexing cluches.
2. Sprang freewheels for high overrunning speeds and for backstops.

Monday, May 4, 2009

Bearing Find

Bearing Find, Bearing Serch, Ball Bearing Serch, Roller Bearing Serch, FAG bearing serch, SKF bearing serch, THK bearing serch, Liner Motion Bearing Serch, FAFNIER Bearing serch, IKO Bearing Serch, Needle Roller Bearing Serch,

Muhammad Ahsan Rana