440mm 380688 77888 4-Row Tapered Roller Bearings for Rolling Mills

• Rolling Body：Roller Bearings
• The Number of Rows：Multi-column
• Outer Dimension：Large (200-430mm)
• Material：Bearing Steel
• Spherical：Aligning Bearings
• Load Direction：Customized

=== Base Info ===

• Model NO.：380688
• Separated：Separated
• Transport Package：Wooden Box
• Specification：Customized
• Trademark：HBB
• Origin：Luoyang, China
• Production Capacity：30000 PCS Yearly

=== Description ===

Basic Info.

Model NO. 380688 Separated Separated Transport Package Wooden Box Specification Customized Trademark HBB Origin Luoyang, China Production Capacity 30000 PCS Yearly

Product Description

HBB High Performance 4 Rows Tapered Roller Bearings for Rolling Mills

Due to the inclination of their rollers, tapered roller bearings accommodate radial and axial loads at the same time. Four-row and double-row tapered roller bearings (pic. 11a and b) are used in rolling mills.

Tapered roller bearings are separable. Despite this fact, however, it is not possible - as is the case with cylindrical roller bearings - to first fit the inner rings onto the roll neck, fit the outer rings into the chock and finally slip the chock onto the roll neck. The complete bearing has to be mounted into the chock, and then the chock together with the bearing pushed onto the roll neck. This means that the bearing inner ring must have a sliding fit on roll neck although technically (because of the circumferential load) it should be a tight fit. The loose fit induces a condition of creep between the bearing bore and the roll neck, resulting in heat-up and wear. However, wear can be minimized by lubricating the surfaces of the inner ring and the roll neck well. To provide space for extra grease, and thus improve the lubrication of the roll neck, spiral grooves are occasionally provided in the inner ring bore (pic. 12). This groove also serves to collect abraded particles. For the same reason radial grooves are also provided in the abutting inner ring faces.

In the case of work rolls supported by four-row tapered roller bearings, wear is moderate due to the low loads. Moreover, the allowable regrinding stock on the work rolls will most probably have been used up - necessitating new rolls - before roll neck wear has reached a point critical to continued bearing performance.
Large tapered roller bearings - like large cylindrical roller bearings - are provided with through-bored rollers and pin-type cages. This cage design is necessary for reversible stands because of the great acceleration and deceleration forces.

For the aforementioned reasons, four-row tapered roller bearings with a cylindrical bore cannot be used for all roll neck applications. Especially high speeds and loads call for a tight-fitted inner ring. In these cases preference is usually given to tapered bore bearings fitted onto a tapered roll neck (pic. 13), whereby the required tight fit is simply achieved.

The inner ring of the design shown in pic. 13a consists of one double cone and two single cones, the outer ring of two double cups. Pic. 13b shows another design with four single cups separated by three spacer rings.



HBB manufactures four-row tapered roller bearings both with metric and inch dimensions and tolerances.

Four Rows Tapered Roller Bearings Products Show:



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