IKO TLA48 Shell Type Needle Roller Bearing, 4 x 8 x 8 mm

IKO TLA shell type needle roller bearings are the standard metric series, caged, with no inner ring. This page lists 53 sizes: 4 to 55 mm shaft, 8 to 63 mm outside diameter and 8 to 30 mm wide.

Shell type needle roller bearings are lightweight with large load ratings. The outer ring is drawn from thin special steel plate, carburised and quenched, and gives the lowest sectional height of the needle roller bearings. They are press-fitted into the housing, so no fixtures for axial positioning are needed, and suit mass-produced products where economy matters. In the standard type a narrow gap between the flange and the shaft helps stop grease leaking out and foreign particles getting in.

The shaft runs directly on the needle rollers. Where the shaft cannot be hardened and ground, use an IRT inner ring: the matching size is shown in the sizes table.

Where this product is used

• Mass-produced assemblies that need an economical bearing
• Press-fit housings with no axial fixing
• Compact shaft supports with a very low sectional height

Features

• Shell type caged needle roller bearing, metric series (TLA), 53 sizes
• Shaft 4 to 55 mm, outside diameter 8 to 63 mm
• Thin drawn outer ring with the lowest sectional height of the needle roller bearings, pressed into the housing with no axial fixing
• Basic dynamic load ratings 1.35 to 38.3 kN, static 1.01 to 95.7 kN
• Allowable rotational speed 5,500 to 75,000 rpm (oil lubrication)

Key specifications

Available sizes

A dash in the inner ring column means no inner ring is listed for that size; ask AIMS if you need one. Fw is the roller set bore diameter, D the outside diameter and C the width; C and C0 are the basic dynamic and static load ratings, and speed is the allowable rotational speed.

Selecting the right option

Choose the size with the Outer Diameter and Width (mm) options. The shaft diameter and width are also in the model number and in the sizes table.

Other shell type series: TLA is the standard metric series, TA the heavy duty metric series and TLA UU the type with seals. For inch shafts see BA and BHA.

Shell type bearings have no inner ring. If the shaft cannot be hardened and ground, pick the IRT inner ring shown against the size in the sizes table and ask AIMS to confirm availability.

Fitting and use

For a steel or cast iron housing, use a shaft tolerance of h6 and a housing bore tolerance of N7. The shaft and housing limits for each size are in the specifications under each variant.

The shaft acts as the raceway: its surface hardness should be 58 to 64 HRC and its surface roughness 0.2 µmRa or less. Where the shaft cannot be hardened and ground, use an inner ring (IRT). The required static safety factor is usually more than 3.

Press the bearing gently into the housing with a suitable tool, with the marked end surface up. The outer ring is thin, so never strike it directly with a hammer. It is fitted with interference, so it does not need axial fixing.

These bearings are not prepacked with grease, so lubricate them before use. The allowable rotational speed in the tables is for oil lubrication; for grease lubrication use up to 60% of it. None of these models has an oil hole. An oil hole version of the shell type is made by adding OH to the end of the number; ask AIMS if you need one.

Related products

Parts that go with this range: TA: the heavy duty metric series; TLA UU: with seals on both sides; IRT inner rings for a shaft that cannot be hardened and ground; BA: inch series.