Double-Row Tapered Roller Bearing (Inward, Tapered Bore) TDIT Type

Specifications

How to choose Tapered Roller Bearings

Points to check when selecting, with the values for this product (Double-Row Tapered Roller Bearing (Inward, Tapered Bore) TDIT Type).

1. 1. Dimension series matching shaft and housing

   This product: Inner diameter d 127.000～519.113 mm

   Bore d matches the shaft diameter and outside diameter D matches the housing bore. Tapered roller bearings come in metric and inch series, and bearings of similar size are not interchangeable. When replacing bearings in existing machinery, confirm the series of the boundary dimension designation, and check inner ring width B and outer ring width C against the step dimensions of the mounting section.

2. 2. Managing preload with assembled width T and tolerance

   Width T is the overall width of the inner and outer rings when assembled, and it affects axial mounting dimensions and the adjustment amount for preload or clearance. The assembled width tolerance class changes the effort required for adjustment, so when used in pairs, confirm T and its tolerance class.

3. 3. Estimating life with basic dynamic load rating

   This product: Basic dynamic load rating Cr 487～6630 kN

   Basic dynamic load rating Cr is the basis for life calculation. From radial and axial loads, the dynamic equivalent load is obtained using factor e and load factor Y1, and rated life is calculated from the ratio to Cr. The listed Cr values range from 9.5 kN to several tens of thousands of kN and vary greatly with the number of rows.

4. 4. Checking shock and low-speed use with static load rating

   For applications with stationary operation, very low speed, or shock loads, check the margin against permanent deformation using the ratio of basic static load rating C0r to the static equivalent load (calculated with Y0). For heavy-duty rolling mills and similar uses, secure capacity with double-row or four-row types.

5. 5. Determining shaft support by load action point position

   Tapered roller bearings have load action points located away from the end face, and the span between supports changes depending on back-to-back or face-to-face arrangement. Use the load action point position a for calculating shaft deflection and reaction forces, and determine the mounting direction accordingly.

6. 6. Matching rotational speed and lubrication method

   The permissible rotational speed is set higher for oil lubrication than for grease lubrication. Confirm that the operating speed is within the value for each lubrication method. For differentials and other applications where energy saving is required, low-torque types showing the friction torque reduction rate are also candidates.

This guide was written by AI based on the listed products' documents and specification items.

About Tapered Roller Bearings and all products

Description

Inward-type (tapered bore) double-row tapered roller bearing. Lists dimensions with bore diameters from 127.000 to 519.113 mm, basic load ratings, fatigue limit load, mounting dimensions, and axial factors.

FAQ

Q. Which bore and outside diameter ranges does the TDIT type double-row tapered roller bearing cover?

A. Bore diameter d ranges from 127.000 to 519.113 mm, and outside diameter D ranges from 182.563 to 736.600 mm.

Q. What is the basic dynamic load rating of the TDIT type?

A. The basic dynamic load rating Cr is 487 to 6630 kN.

Q. What applications is the TDIT type double-row tapered roller bearing suited for?

A. It is a bearing for supporting heavy loads and is used in main spindles of industrial machinery and rotating parts subject to heavy loads.

Q. What is the inner ring structure of the TDIT type?

A. The inner ring has a tapered bore, allowing mounting via the tapered bore. The double-row arrangement provides high load capacity.

Q. Where can the dimensions and ratings of the TDIT type be found?

A. They are listed in a table showing dimensions, basic load ratings, fatigue limit load, mounting dimensions, and axial factors for the inward-type (tapered bore) double-row tapered roller bearing.

Written by AI based on the content of the source documents.

Source documents

• Catalog JTEKT 大形転がり軸受カタログ（技術解説・軸受寸法表） Open page 136
  Found on: https://koyo.jtekt.co.jp/support/catalog-download/