Oil Management System

Abstract

Method and a system for oil management where a common pressure shield contains all oil management functions for treatment of the mixture of oil and refrigerant leaving the compressor, and returning the oil to the compressor. The pressure shield may comprise at least the following components related to oil management; an oil separator from which oil is flowing to an oil sump, an oil cooler connected to the oil sump, a mixing valve in which the oil from the oil cooler is mixed with oil from the oil sump for achieving an optimised oil temperature, an oil filter for filtering the mixed oil, the mixed oil being returned from the oil filter to the compressor, and where at least the mentioned components can operate at a pressure level substantially equivalent to the discharge pressure at the compressor.

1 . Oil management system primarily related to a refrigeration system comprising at least one compressor, which compressor comprises an inlet for refrigerant, which compressor has a discharge for refrigerant connected to means for oil separation, from which oil separation means, oil is led back towards the compressor characterized in that the compressor discharge operating in conjunction with a pressure shield, which pressure shield comprises at least the following components related to oil management; an oil separator from which oil is flowing to an oil sump; an oil cooler is connected to the oil sump; a mixing valve in which the oil from the oil cooler is mixed with oil from the oil sump for achieving an optimised oil temperature; an oil filter, for filtering the mixed oil, where the oil is returned from the oil filter to the compressor, where at least the mentioned components operate at a pressure level substantially equivalent to the discharge pressure at the compressor. 
   
   
       2 . Oil management system according to  claim 1 , characterized in that the oil cooler is formed as a longitudinal heat exchanger angled at a first angle related to the longitudinal axis of the pressure shield. 
   
   
       3 . Oil management system according to  claim 2 , characterized in that the first angle of the heat exchanger related to the longitudinal axis of the pressure shield is at least eight degrees. 
   
   
       4 . Oil management system according to  claim 1 , characterized in that the heat exchanger comprises a number of longitudinal pipes surrounded by fins, where a first cooling media is flowing inside the pipes, where oil is flowing outside the pipes, where heat is transmitted from the oil towards the first cooling media. 
   
   
       5 . Oil management system according to  claim 1 , characterized in that the heat exchanger is formed inside a heat exchanger shield, which shield has inlet openings in the lower part for forming an access to an oil sump formed in the lower part of the pressure shield. 
   
   
       6 . Oil management system according to  claim 1  characterized in that longitudinal oil channels are formed inside the heat exchanger shield between the shield and the fins of the heat exchanger. 
   
   
       7 . Oil management system according to  claim 1 , characterized in that the channels between the heat exchanger and the related shield are partly blocked to form at least two sections, where oil is forced to flow between the fins to flow from a first section to a second section. 
   
   
       8 . Oil management system according to  claim 1 , characterized in that the heat exchanger has a separated section, where the heat exchanger shield has an inlet and an outlet for a cooling medium used for cooling electronic switches, which switches control a motor connected to the compressor. 
   
   
       9 . Oil management system according to  claim 1 , characterized in that the pressure shield has at least one inlet opening for refrigerant, which inlet opening comprises strainers for a first oil separation. 
   
   
       10 . A method for oil management primary related to a refrigeration system, where compression means has a discharge for refrigerant connected to means for oil separation, from which oil separation means, oil is led back towards the compression means characterized in that the compression means is operating in conjunction with a pressure shield, which pressure shield comprises at least the following operations related to oil management, separating oil from refrigerant, cooling the oil, mixing the cooled oil with warm oil for achieving the optimal oil temperature in a mixing valve, filtering the oil, and returning oil to the compression means, which operations is performed at a pressure level substantially equivalent to the discharge pressure at the compression means. 
   
   
       11 . A method for oil management according to  claim 10 , characterized in that the heat exchanger has a separated section for cooling a medium used for cooling electronic switches which switches controls a motor connected to the compressor.