Method and Arrangement for Sealing a Propeller Shaft of a Marine Vessel

Abstract

A method and an arrangement for sealing a propeller shaft. The propeller shaft is rotatably supported with a bearing arrangement inside a pod that is suspended at a hull of the marine vessel. The bearing arrangement includes at least two seal rings axially spaced apart from each other such that at least one lubricant seal chamber is delimited. The arrangement includes a lubrication arrangement for conducting lubricant to and from said bearing arrangement. The lubrication arrangement includes an additional lubrication circulation line for conducting a part of said flow of lubricant to and from said at least one lubricant seal chamber. The lubrication arrangement being additionally configured to create a flow of lubricant in the additional lubricant circulation line and in said at least one lubricant seal chamber.

1 . A method for sealing a propeller shaft of a marine vessel,
 wherein the propeller shaft is arranged at a pod that is suspended at a hull of the marine vessel,   wherein a propeller is attached to a driving end of the propeller shaft, wherein the driving end projects out of the pod,   wherein the propeller shaft is rotatably supported with a bearing arrangement inside the pod,   wherein at least two seal rings are provided axially spaced apart from each other in an axial direction of the propeller shaft and engaging the outer circumference of the propeller shaft such that at least one lubricant seal chamber is delimited between adjacent seal rings, and   wherein the bearing arrangement comprises a lubrication arrangement having a lubricant circulation line for conducting lubricant to said bearing arrangement and for conducting lubricant from said bearing arrangement, and a lubricant circulator configured to create a flow of lubricant in the lubricant circulation line and in the bearing arrangement,   wherein providing the lubrication arrangement with an additional lubrication circulation line including a first line part for conducting a part of said flow of lubricant to said at least one lubricant seal chamber and including a second line part for conducting said part of said flow of lubricant from said at least one lubricant seal chamber, and by creating a flow of lubricant in the first line part and in the second line part of the additional lubricant circulation line and in said at least one lubricant seal chamber.   
     
     
         2 . The method according to  claim 1 ,
 wherein creating the flow of lubricant in the first line part and in the second line part of the additional lubricant circulation line and in said at least one lubricant seal chamber by means of the lubricant circulator.   
     
     
         3 . The method according to  claim 1   wherein connecting the first line part in fluid connection with the lubricant circulation line at a point downstream of the lubricant circulator and upstream of said at least one lubricant seal chamber, and connecting the first line part in fluid connection with said at least one lubricant seal chamber, and   by conducting said part of said flow of lubricant from the lubricant circulation line to said at least one lubricant seal chamber in the first line part.   
     
     
         4 . The method according to  claim 1   wherein connecting the first line part in fluid connection with the lubricant circulation line at a point downstream of the lubricant circulator and upstream of said at least one lubricant seal chamber, and connecting the first line part in fluid connection with a bottom of said at least one lubricant seal chamber, and   by conducting said part of said flow of lubricant from the lubricant circulation line into the bottom of said at least one lubricant seal chamber in the first line part.   
     
     
         5 . The method according to  claim 1   wherein connecting the first line part in fluid connection with a bottom of the bearing arrangement, and connecting the first line part in fluid connection with a bottom of said at least one lubricant seal chamber, and   by conducting said part of said flow of lubricant from the bottom of the bearing arrangement into the bottom of said at least one lubricant seal chamber in the first line part.   
     
     
         6 . The method according to  claim 1   wherein providing the second line part by means an equalizing channel between said at least one lubricant seal chamber and the bearing arrangement, and   by conducting said part of said flow of lubricant from said at least one lubricant seal chamber to the bearing arrangement in the second line part.   
     
     
         7 . The method according to  claim 1   wherein connecting the second line part in fluid connection with a top of said at least one lubricant seal chamber and in fluid connection with the bearing arrangement, and   by conducting said part of said flow of lubricant from the top of said at least one lubricant seal chamber into the bearing arrangement in the second line part.   
     
     
         8 . The method according to  claim 1   wherein connecting the second line part in fluid connection with a bottom of said at least one lubricant seal chamber and in fluid connection with the lubricant circulation line at a point downstream of the bearing arrangement and upstream of the lubricant circulator, and   by conducting said part of said flow of lubricant from the bottom of said at least one lubricant seal chamber into the lubricant circulation line in the second line part.   
     
     
         9 . An arrangement for sealing a propeller shaft of a marine vessel,
 wherein the propeller shaft is arranged at a pod that is suspended at a hull of the marine vessel,   wherein a propeller is attached to a driving end of the propeller shaft, wherein the driving end projects out of the pod,   wherein the propeller shaft is rotatably supported with a bearing arrangement inside the pod,   wherein at least two seal rings are provided axially spaced apart from each other in the axial direction of the propeller shaft and engaging the outer circumference of the propeller shaft such that at least one lubricant seal chamber is delimited between adjacent seal rings, and   wherein the bearing arrangement comprises a lubrication arrangement comprising a lubricant circulation line for conducting lubricant to said bearing arrangement and for conducting lubricant from said bearing arrangement, and a lubricant circulator configured to create a flow of lubricant in the lubricant circulation line and in the bearing arrangement,   wherein the lubrication arrangement includes an additional lubrication circulation line for conducting a part of said flow of lubricant to said at least one lubricant seal chamber and for conducting said part of said flow of lubricant from said at least one lubricant seal chamber, and   by the lubrication arrangement being additionally configured to create a flow of lubricant in the additional lubricant circulation line and in said at least one lubricant seal chamber.   
     
     
         10 . The arrangement according to  claim 9   wherein the lubricant circulator of the lubrication arrangement being additionally configured to create a flow of lubricant in the additional lubricant circulation line and in said at least one lubricant seal chamber.   
     
     
         11 . The arrangement according to  claim 9   wherein the first line part being in fluid connection with the lubricant circulation line at a point downstream of the lubricant circulator and upstream of said at least one lubricant seal chamber and in fluid connection with said at least one lubricant seal chamber, wherein the first line part being configured to conduct said part of said flow of lubricant from the lubricant circulation line to said at least one lubricant seal chamber.   
     
     
         12 . The arrangement according to  claim 9   wherein the first line part being in fluid connection with the lubricant circulation line at a point downstream of the lubricant circulator and upstream of said at least one lubricant seal chamber and in fluid connection with a bottom of said at least one lubricant seal chamber, wherein the first line part being configured to conduct said part of said flow of lubricant from the lubricant circulation line into the bottom of said at least one lubricant seal chamber.   
     
     
         13 . The arrangement according to  claim 9   wherein the first line part being in fluid connection with a bottom of the bearing arrangement, and in fluid connection with a bottom of said at least one lubricant seal chamber, wherein the first line part being configured to conduct said part of said flow of lubricant from the bottom of the bearing arrangement into the bottom of said at least one lubricant seal chamber.   
     
     
         14 . The arrangement according to  claim 9   wherein the second line part being formed by an equalizing channel between said at least one lubricant seal chamber and the bearing arrangement, wherein the first line part being configured to conduct said part of said flow of lubricant from said at least one lubricant seal chamber to the bearing arrangement.   
     
     
         15 . The arrangement according  claim 9   wherein the second line part being in fluid connection with a top of said at least one lubricant seal chamber and in fluid connection with the bearing arrangement, wherein the second line part being configured to conduct said part of said flow of lubricant from the top of said at least one lubricant seal chamber into the bearing arrangement.   
     
     
         16 . The arrangement according to  claim 9   wherein the second line part being in fluid connection with a bottom of said at least one lubricant seal chamber and in fluid connection with the lubricant circulation line at a point downstream of the bearing arrangement and upstream of the lubricant circulator, wherein the second line part being configured to conduct said part of said flow of lubricant from the bottom of said at least one lubricant seal chamber into the lubricant circulation line.   
     
     
         17 . The method according to  claim 2   wherein connecting the first line part in fluid connection with the lubricant circulation line at a point downstream of the lubricant circulator and upstream of said at least one lubricant seal chamber, and connecting the first line part in fluid connection with said at least one lubricant seal chamber, and   by conducting said part of said flow of lubricant from the lubricant circulation line to said at least one lubricant seal chamber in the first line part.   
     
     
         18 . The method according to  claim 2   wherein connecting the first line part in fluid connection with the lubricant circulation line at a point downstream of the lubricant circulator and upstream of said at least one lubricant seal chamber, and connecting the first line part in fluid connection with a bottom of said at least one lubricant seal chamber, and   by conducting said part of said flow of lubricant from the lubricant circulation line into the bottom of said at least one lubricant seal chamber in the first line part.   
     
     
         19 . The method according to  claim 2   wherein connecting the first line part in fluid connection with a bottom of the bearing arrangement, and connecting the first line part in fluid connection with a bottom of said at least one lubricant seal chamber, and   by conducting said part of said flow of lubricant from the bottom of the bearing arrangement into the bottom of said at least one lubricant seal chamber in the first line part.   
     
     
         20 . The method according to  claim 2   wherein providing the second line part by means an equalizing channel between said at least one lubricant seal chamber and the bearing arrangement, and   by conducting said part of said flow of lubricant from said at least one lubricant seal chamber to the bearing arrangement in the second line part.