Patent Publication Number: US-2016236250-A1

Title: Seal assembly and neck seal for rolling mill

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority from U.S. Provisional Application Ser. No. 61/756,506 filed Jan. 25, 2013, the entire contents and substance of which are herein incorporated by reference. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     Aspects of the present invention relate generally to the use of flexible seals for bearing applications and with the seal assembly employed in a rolling mill using oil film bearing technologies. Aspects of the present invention are concerned in particular with improvements to the seal assembly and neck seal that prevent contamination ingress and oil escape from such bearings. 
     2. Description of Related Art 
     With reference to  FIG. 1 , a known oil film bearing assembly is shown comprising a roll  10  having an end face  12  and a tapered neck section  14  leading to a reduced tapered diameter  16  surrounded by a sleeve  18 . The sleeve  18  is fixed to the roll  10  by a key or other device (not shown) for rotation within a bushing  20  contained by and fixed relative to a roll stand chock  22 . 
     A flexible neck seal  24  is mounted on the tapered roll section  14  for rotation therewith. The seal  24  has a circular body and is held in place between the sleeve  18  and the roll taper  14 . 
     Inboard and outboard flanges  26 ,  28  project radially outwardly from the seal body. As herein employed, the term “inboard” means a component closest to the roll end face  12 , and the term “outboard” means a component closest to the bushing  6  and chock  22 . A flinger  30  projects angularly toward the chock  22 . 
     The inboard and outboard flanges  26 ,  28  have oppositely directed lip seals arranged to contact annular inboard and outboard sealing surfaces  32 ,  34  of a seal end plate  36 . The seal end plate is fixed to and cooperates with the chock  22  to create a sump  38 . The annular sealing surfaces  32 ,  34  of the seal end plate  36  are separated by an inwardly projecting circular flange  37  serving as a mechanical dam. A seal inner ring  40  and a coolant guard  42  complete the seal assembly. 
     In operation the roll  10 , neck seal  24 , seal inner ring  40 , and sleeve  18  rotate together while the bushing  20 , chock  22 , seal end plate  36 , and coolant guard  42  remain static. Oil is supplied between the sleeve  18  and bushing  20 . This oil is formed into a thin lubricating film at the bearing load zone before emerging between the sleeve  18  and bushing  20  for collection in the sump  38 . 
     The flinger  30  and outboard flange  28  serve to retain the oil in the bearing, whereas the coolant guard  42 , inner seal ring  40 , and inboard flange  26  serve to exclude the external contaminates from penetrating to the bearing. 
     SUMMARY 
     Briefly described, aspects of the present invention relate to an improved seal assembly and neck seal. In accordance with exemplary embodiments, and in comparison to the conventional seal and sealing arrangement depicted in  FIG. 1 , the seal and seal end plate of the present invention have decreased widths, thereby making it possible to either increase the width of the roll barrel, or to employ alternative bearing geometries within the same roll stand in order to improve the roll stand&#39;s load capacity. 
     The decreased widths of the seal and seal end plate is made possible by eliminating the flange  37  of the conventional seal plate in favor of a stepped interior defining inboard and outboard sealing surfaces, with the outboard sealing surface having a diameter larger than the diameter of the inboard sealing surface, and with both sealing surfaces being connected by and annular dam surface. The seal is correspondingly reconfigured to provide an outboard sealing flange having an outer diameter larger than the outer diameter of the inboard sealing flange. 
     These and other features and advantages of the present invention will now be described in more detail with reference to the accompanying drawings, wherein: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partial cross sectional view of a conventional oil film bearing assembly; and 
         FIG. 2  is a partial cross sectional view of an oil film bearing assembly and seal, in accordance with exemplary embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     To facilitate an understanding of the embodiments, principles, and features of the present invention, they are explained hereinafter with reference to the implementation in illustrative embodiments. In particular, they are described in the context of being a seal assembly and neck seal for an oil film bearing in a rolling mill. 
     The components and materials described hereinafter as making up the various embodiments are intended to be illustrative and not restrictive. Many suitable components and materials that would perform the same or a similar function as the materials and components described herein are intended to be embraced within the scope of embodiments of the present invention. 
       FIG. 2  illustrates an oil film bearing assembly and neck seal in accordance with exemplary embodiments of the present invention. The seal end plate  36   a  is reconfigured with a stepped interior defining inboard and outboard annular sealing surfaces  32   a ,  34   a , connected by an annular dam surface  37   a . The diameter of the outboard sealing surface  34   a  is larger than the diameter of the inboard sealing surface  32   a . Both sealing surfaces  32   a ,  32   b  are preferably parallel to the axis “A” of rotation of the roll  10 , with the dam surface  37   a  preferably being perpendicular to the axis A. 
     The neck seal  24   a  is correspondingly reconfigured with the outer diameter of the outboard flange  28   a  being larger than that of the inboard flange  26   a.    
     These reconfigured geometries of the neck seal  24   a  and seal end plate  36   a  make it possible to eliminate the flange  37  of the conventional seal end plate  36 , which in turn allows the widths of both the neck seal and the seal end plate to be beneficially reduced. 
     There are many advantages of this arrangement. For example and not limitation, and in no particular order, first, the reduced widths of the neck seal and seal end plate allow for the potential increase in the width of the roll  10  (shown at “L” in  FIG. 2 ) in the same rolling mill stand with its obvious benefits to the mill user. Second, alternatively, the standard roll width can be maintained, with the reduced widths of the seal and seal end plate being utilized for alternate bearing geometries within the same rolling mill stand designed to improve the load capacity of the roll stand. Third, the reconfigured seal assembly simplifies manufacture and assembly of the seal components. 
     While embodiments of the present invention have been disclosed in exemplary forms, it will be apparent to those skilled in the art that many modifications, additions and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents, as set forth in the following claims.