Process for reduction of time in gas carburizing process and cooling apparatus therefor

Abstract

A process for reduction of time in gas carburizing process and a cooling system therefor is provided. The process includes the steps of placing a part into an atmospheric carburizing furnace, maintaining the step-wise temperature of the carburizing furnace during heating the part in the carburizing furnace, heating the part consecutively at the first pre-set temperature, second pre-set temperature and third pre-set temperature for the duration of pre-set constant time interval while adding a hydrocarbon gas into the carburizing furnace, and based on the requirement of the depth, heating the part at the fourth pre-set temperature for a duration of variable time and for variable carbon potential in accordance with the requirement by adding the hydrocarbon gas into the carburizing furnace, and heating the part at the fourth pre-set temperature, fifth pre-set temperature and sixth pre-set temperature for a duration of variable time and for variable carbon potential.

1 . A process for reduction of time in gas carburizing process, the process comprising the steps of and characterized by:
 a) placing a part into an atmospheric carburizing furnace;   b) maintaining the step-wise temperature of the carburizing furnace during the heating of the part in the carburizing furnace;   c) heating the part at the first pre-set temperature for the duration of pre-set constant time interval while adding a hydrocarbon gas into the carburizing furnace;   d) heating the part at the second pre-set temperature for the duration of pre-set constant time interval while adding the hydrocarbon gas along with methanol into the carburizing furnace;   e) heating the part at the third pre-set temperature for the duration of pre-set constant time interval while adding the hydrocarbon gas into the carburizing furnace; and   
       based on the requirement of the depth,
 f) heating the part at the fourth pre-set temperature for a duration of variable time and for variable carbon potential in accordance with the requirement by adding the hydrocarbon gas into the carburizing furnace; and 
 g) heating the part at the fifth pre-set temperature for a duration of variable time and for variable carbon potential in accordance with the requirement by adding the hydrocarbon gas into the carburizing furnace; 
 h) heating the part at the sixth pre-set temperature for a duration of variable time and for variable carbon potential in accordance with the requirement by adding the hydrocarbon gas into the carburizing furnace, and 
 i) quenching the part using quenching oil flowing in the quenching oil circulation pipe, wherein the process resulting in reduced processing time and increased efficiency. 
 
     
     
         2 . The process as claimed in  claim 1 , wherein the pre-set constant time interval is 10 minute. 
     
     
         3 . The process as claimed in  claim 1 , wherein the hydrocarbon gas is selected from the group consisting of liquid petroleum gas (LPG) and Propane. 
     
     
         4 . The process as claimed in  claim 1 , wherein the first pre-set temperature, second pre-set temperature, third pre-set temperature, fourth pre-set temperature, fifth pre-set temperature and sixth pre-set temperature of the furnace for heating the part are 800° C., 850° C., 900° C., 930° C., 940° C. and 965° C. 
     
     
         5 . A cooling apparatus for a process for reduction of time in gas carburizing process, said cooling apparatus consisting essentially of:
 a quenching chamber ( 1 );   a propeller for agitation ( 3 );   work movement elevator ( 4 );   a work basket ( 5 );   an elevator drive cylinder ( 6 );   quench oil circulation pipe ( 7 ) provided with an input end and exit/output end, wherein the quenching oil is directed to flow through with a pre-set/pre-determined/selected flow rate facilitated by the propeller ( 3 );   an agitation motor ( 2 ) operably coupled with input end of the quench oil circulation pipe ( 7 ) to facilitate the flow of the quenching oil through the circulation pipe ( 7 ); and   a rectification device ( 8 ) to facilitate the equalization of the flow rate of the quenching oil,   wherein said cooling apparatus configured to facilitate homogeneous cooling and to provide improvement in the severity of quench,   wherein said cooling apparatus configured further to function in at least one mode of operation.   
     
     
         6 . The process as claimed in  claim 5 , wherein the rating of the propeller is in the range of 1200 rpm˜1500 rpm. 
     
     
         7 . The process as claimed in  claim 5 , wherein the severity of the quench is 0.8 per inch. 
     
     
         8 . The cooling apparatus as claimed in  claim 5 , wherein the at least one mode of operation is selected from the group consisting of manual mode and automatic mode.