About features of roller tapered bearings in inch sizes

Taper roller bearings are very widespread. They are used in mechanical transmissions and rail transport. But most often the average consumer encounters them when repairing a car - it is difficult to imagine the hub units of automobiles without tapered roller bearings.

Finding the required bearing of metric dimensions (the main parameters of which are determined in millimeters, often as a whole, although fractional ones with a step of 0.25 mm are possible) does not often arise problems - it is enough to know the diameter of the mounting shaft, the diameter of the outer ring and the height of the bearing assembly. If there are difficulties with the measurement of these parameters, then refer to the data indicated directly on the bearing itself. It has the same marking both on the outer and the inner cage, respectively, having only a “half” of a tapered roller bearing, you can easily choose a replacement.

It is much easier to get lost in an inch bearing, whose basic parameters cannot be so easily determined (it is important to know the dimensions with an accuracy of one thousandth of a millimeter). Their full marking is a combination of two numbers, separated by a fractional line: before the line is indicated the marking of the inner cage, after it - the outer one. Take the bearing (hereinafter, for example, bearings of the brand Fersa, Spain are taken) LM102949 / LM102910. LM102949 will be indicated on its inner ring, LM102910 will be on the outer ring.

However, knowing the marking of only one “half” of the inch-bearing, you can buy absolutely the wrong bearing that you need. If you take the inner clip with marking LM104949, then under it there are three options for the outer one: LM104911, LM104912 and JLM104910. The difference of the three bearings - in their sizes (diameters of the outer cages and height assembly).

Not only the inner ring can be completed with different outer ones. Consider four bearings: LM29749 / LM29710, LM29748 / LM29710, LM29748 / LM29711 and LM29749 / LM29711. As can be seen, the four different positions are combinations of two inner and two outer rings. In this case, knowing the marking of only one holder, it is impossible to choose the right bearing.

To be absolutely sure of the correct selection of roller tapered bearing inch size, you need to know its full marking. Otherwise, the possibility of error is not excluded.

Convenient catalog of tapered tapered inch bearings on the website of the company VPK-Bearing will help you find the right bearing, and detailed information and photos will allow you to make the right choice.