Magnesium hot rolling method and apparatus

Abstract

A magnesium alloy hot rolling method includes: a first rolling step in which a magnesium plate (M 0 , M 1 ) is rolled reciprocatingly between an upstream heating furnace ( 2 ) which is located on an upstream side of a rolling mill ( 1 ) and which heats the magnesium plate (M 0 , M 1 ), and a upstream heating furnace ( 3 ) which is located on a downstream side of the rolling mill ( 1 ) and which heats the magnesium plate (M 0 , M 1 ); and a second rolling step in which the temperature of respective end portions of the magnesium plate (M 0 , M 1 ) on both the upstream and downstream sides is maintained while the magnesium plate (M 0 , M 1 ) is being rolled reciprocatingly between an upstream temperature maintaining apparatus ( 5 ) which transports the heated magnesium plate (M 0 , M 1 ) while maintaining the temperature thereof, and a downstream temperature maintaining apparatus ( 6 ) which transports the heated magnesium plate (M 0 , M 1 ) while maintaining the temperature thereof. According to the magnesium hot rolling apparatus of the present invention and to the magnesium hot rolling method of the present invention which uses this apparatus, it is possible to prevent any deterioration in the quality of a product which is due to temperature variations during the hot rolling of magnesium alloy.

1 . A magnesium alloy hot rolling method comprising:
 a first rolling step in which a magnesium plate is rolled reciprocatingly between an upstream heating furnace which is located on an upstream side of a rolling mill and which heats the magnesium plate, and a upstream heating furnace which is located on a downstream side of the rolling mill and which heats the magnesium plate; and   a second rolling step in which the temperature of respective end portions of the magnesium plate on both the upstream and downstream sides is maintained while the magnesium plate is being rolled reciprocatingly between an upstream temperature maintaining apparatus which is located further on the upstream side than the upstream heating furnace and which transports the magnesium plate which has been heated by the upstream heating furnace while maintaining the temperature thereof, and a downstream temperature maintaining apparatus which is located further on the downstream side than the upstream heating furnace and which transports the magnesium plate which has been heated by the upstream heating furnace while maintaining the temperature thereof.   
     
     
         2 . The magnesium alloy hot rolling method according to  claim 1 , wherein there is provided a wind-on step in which, while tension is applied by a tension applying apparatus which is located on the downstream side of the downstream temperature maintaining apparatus to the magnesium plate which has been rolled to a predetermined thickness, the magnesium plate is wound onto a winder which is placed further on the downstream side than the downstream temperature maintaining apparatus. 
     
     
         3 . A magnesium alloy hot rolling apparatus comprising:
 a rolling mill which performs reciprocating rolling on a magnesium plate;   an upstream heating furnace which is located on the upstream side of the rolling mill and which heats the magnesium plate;   a upstream heating furnace which is located on the downstream side of the rolling mill and which heats the magnesium plate;   an upstream temperature maintaining apparatus which is located further on the upstream side than the upstream heating furnace, and which transports the magnesium plate which has been heated by the upstream heating furnace and also maintains the temperature of upstream side end portions thereof; and   a downstream temperature maintaining apparatus which is located further on the downstream side than the upstream heating furnace, and which transports the magnesium plate which has been heated by the upstream heating furnace and also maintains the temperature of downstream side end portions thereof.   
     
     
         4 . The magnesium alloy hot rolling apparatus according to  claim 3 , wherein a plurality of groups of pinch rollers which sandwich the magnesium plate in the thickness direction thereof and adjust the transporting speed thereof are provided respectively between the rolling mill and the upstream heating furnace and between the rolling mill and the upstream heating furnace. 
     
     
         5 . The magnesium alloy hot rolling apparatus according to  claim 4 , wherein working rollers of the rolling mill and the plurality of groups of pinch rollers which are located on the upstream and downstream sides of the rolling mill are heating rollers. 
     
     
         6 . The magnesium hot rolling apparatus according to  claim 3  or  4 , wherein there are provided:
 a tension applying apparatus which is located on the downstream side of the downstream temperature maintaining apparatus and which applies tension to the magnesium plate; and 
 a winder which is located further on the downstream side than the tension applying apparatus and onto which the magnesium plate is wound.