30203 MTM 17x40x13.25 mm - Single Row Tapered Roller Bearing

30203 MTM 17x40x13.25 mm - Single Row Tapered Roller Bearing

30203 MTM is a single row tapered roller bearing with nominal dimensions of 17x40x13.25 mm. It belongs to the standardized 302 tapered roller bearing series and is designed to accommodate combined radial and axial loads. Its construction consists of a tapered inner ring, tapered rollers, a cage, and a separable outer ring. The bearing supports axial loads in one direction and requires appropriate axial adjustment during installation.

Technical Specifications - 30203 MTM

The dimensional values correspond to the standard 30203 bearing geometry. The exact MTM execution, cage material, load ratings, speed limits, and manufacturing tolerances should be confirmed against the manufacturer's product documentation.

What Does 30203 MTM Mean?

The designation identifies the bearing family, dimensional size, and brand.

• 302 - Standard series of single row tapered roller bearings.

• 03 - Bore code corresponding to a nominal bore diameter of 17 mm.

• MTM - Bearing brand.

The designation does not contain an additional suffix specifying increased clearance, special sealing, a particular lubricant, or a special precision class.

These characteristics must not be assumed without manufacturer confirmation.

Confirmed MTM Product Data

A distributor listing specifically identifies the 30203-MTM bearing and provides the following additional values.

These values are supported by the MTM-specific distributor listing, rather than being transferred from SKF or Timken. They have not been independently confirmed against an official MTM manufacturer datasheet.

Construction and Operating Principle

The 30203 MTM consists of:

• An inner ring with a tapered raceway.

• Tapered rollers held in position by a cage.

• A separate outer ring, commonly called the cup.

The inner ring, rollers, and cage form an assembly that can be separated from the outer ring. This construction facilitates installation, inspection, and adjustment.

The tapered geometry allows the bearing to accommodate radial loads together with axial loads acting in one direction. Axial loads acting in the opposite direction require an appropriately arranged opposing bearing.

Axial Clearance and Preload

Unlike many standard deep groove ball bearings, tapered roller bearings require particular attention to axial adjustment.

Depending on the bearing arrangement, the installer must establish suitable operating clearance or preload.

Excessive preload can increase friction, operating temperature, and bearing wear. Excessive clearance can reduce shaft positioning accuracy and adversely affect load distribution.

The correct adjustment depends on the complete bearing arrangement, shaft and housing fits, operating temperature, and application requirements.

30203 MTM vs Other 30203 Bearings

The basic designation 30203 is used by multiple bearing manufacturers.

For example, official SKF and Timken technical information confirms the same nominal dimensions of 17x40x13.25 mm for their respective 30203 products.

However, load ratings, cage execution, manufacturing tolerances, and permissible operating speeds may differ between manufacturers.

A bearing with the same dimensions should therefore not be treated as automatically interchangeable without checking its technical specifications.

Alternative Designations and Search References

Natural designation formats include:

• 30203 MTM

• MTM 30203

• 30203-MTM

• MTM30203

• 30203 17x40x13.25 mm

The designation 30203 identifies the basic bearing size and construction. The MTM brand distinguishes this product from bearings supplied by other manufacturers.

No unverified OEM references are assigned to this bearing.

Bearing Selection and Interchangeability

Before purchasing the 30203 MTM, verify the following:

• Complete designation and manufacturer.

• Bore diameter of 17 mm.

• Outside diameter of 40 mm.

• Overall bearing width of 13.25 mm.

• Inner ring width of 12 mm and outer ring width of 11 mm.

• Radial and axial load requirements.

• Bearing arrangement and axial load direction.

• Required clearance or preload.

• Shaft and housing fits.

• Rotational speed and operating temperature.

• Lubrication method and contamination protection.

Particular attention should be paid to the distinction between overall width T and inner ring width B. For the 30203 bearing, the overall width is 13.25 mm, not 12 mm.

Typical Applications

Single row tapered roller bearings are commonly used in mechanical assemblies requiring combined radial and axial load support.

Typical applications for this bearing design include rotating shafts, industrial transmission assemblies, gearboxes, and bearing arrangements requiring controlled axial positioning.

These are general applications of tapered roller bearings, not verified OEM applications for the specific 30203 MTM product.

Installation and Maintenance

Before installation, clean and inspect the shaft, housing, and bearing seating surfaces.

Mount the inner and outer rings using appropriate tools, applying installation forces only to the ring being fitted. Avoid transmitting mounting forces through the rolling elements.

After assembly, establish the specified axial clearance or preload. Check that the shaft rotates smoothly and that the bearing arrangement is correctly lubricated.

Because the 30203 MTM has an open construction, contamination protection and lubricant retention must be provided by the surrounding machine design where necessary.

Store the bearing in a dry, clean environment and protect its raceways from corrosion and mechanical damage.

Frequently Asked Questions - 30203 MTM

1. What are the dimensions of the 30203 MTM bearing?

The nominal dimensions are 17x40x13.25 mm: 17 mm bore diameter, 40 mm outside diameter, and 13.25 mm overall width.

2. Is the 30203 MTM a ball bearing or a roller bearing?

It is a single row tapered roller bearing. It uses tapered rollers rather than balls.

3. Can the 30203 MTM accommodate axial loads?

Yes. It accommodates combined radial and axial loads, with axial load support in one direction.

4. Is the 30203 MTM separable?

Yes. The inner ring assembly, including rollers and cage, can be separated from the outer ring.

5. Does the 30203 MTM require axial adjustment?

Yes. The bearing arrangement must be assembled with appropriate axial clearance or preload according to the application.

6. Can an SKF or Timken 30203 replace the MTM bearing?

A replacement may be possible, but dimensional compatibility alone is insufficient. Load ratings, bearing execution, tolerances, and operating requirements must also be checked.

7. Is the overall width 12 mm or 13.25 mm?

The overall bearing width T is 13.25 mm. The inner ring width B is 12 mm.

8. Is the 30203 MTM sealed?

The standard 30203 tapered roller bearing has an open construction. External sealing may be required in the machine assembly.

30203 MTM - Key Product Information

The 30203 MTM is a single row tapered roller bearing with dimensions of 17x40x13.25 mm. It features tapered rolling elements, a separable outer ring, and an inner ring assembly with rollers and cage. The bearing accommodates combined radial and axial loads, supporting axial forces in one direction. Correct axial clearance or preload is essential during installation.

The 30203 MTM is offered by simmering.pl, a specialist supplier of industrial bearings and technical components operated by TG Ersatzteile Polska Sp. z o.o. The company maintains a warehouse in Lublin, Poland, and provides domestic and international shipping services.