Burner Unit, Furnace and Method for Operation

Abstract

The invention relates to a burner unit for a furnace, in particular a continuous furnace, a tunnel furnace or the like, to a furnace and to a method for operating a furnace, the burner unit having at least two burners which are configured for burning a combustion gas, the burner unit having a gas pipe and an air pipe for supplying the burners with combustion gas, the burner unit having at least one gas metering valve in the gas pipe and at least one air metering valve in the air pipe, the gas metering valve and the air metering valve being controllable by means of a shared control device, the gas metering valve being a magnet valve and the air metering valve being a magnet valve as well.

1 - 16 . (canceled) 
     
     
         17 . A burner unit for a furnace, comprising:
 at least two burners configured for burning a combustion gas;   a gas pipe;   an air pipe;   at least one gas metering valve in the gas pipe;   at least one air metering valve in the air pipe; and   a shared control device adapted for controlling the at least one gas metering valve and the at least one air metering valve wherein the at least one gas metering valve and the at least one air metering valve are magnet valves.   
     
     
         18 . The burner unit according to  claim 17 , further including a regulating apparatus configured for synchronizing a corresponding operating state of the at least one gas metering valve and the at least one air metering valve. 
     
     
         19 . The burner unit according to  claim 17  wherein the gas pipe and the air pipe are branched toward the at least two burners, the at least two burners being switched in series at the gas pipe and the air pipe. 
     
     
         20 . The burner unit according to  claim 17 , including one gas metering valve and one air metering valve assigned to each burner. 
     
     
         21 . The burner unit according to  claim 17 , including a check valve in (a) the gas pipe, (b) the air pipe or (c) the gas pipe and the air pipe of the burner unit. 
     
     
         22 . The burner unit according to  claim 17 , including a check valve in (a) the gas pipe, (b) the air pipe or (c) the gas pipe and the air pipe of each burner. 
     
     
         23 . The burner unit according to  claim 17 , wherein an opening cross section of the at least one air metering valve is larger than an opening cross section of the at least one gas metering valve. 
     
     
         24 . The burner unit of  claim 17 , wherein the burner unit has at least 3 or more burners. 
     
     
         25 . The burner unit of  claim 17 , further including a fan adapted for conveying air into the air pipe. 
     
     
         26 . The burner unit of  claim 17 , wherein the air pipe of the burner unit is connected to a central air circulation pipe of a furnace. 
     
     
         27 . A furnace having at least one burner unit as set forth in  claim 17 . 
     
     
         28 . A method for operating a furnace, comprising:
 supplying a combustion gas to at least two burners via a gas pipe and an air pipe; and   controlling at least one gas metering valve in the gas pipe and at least one air metering valve in the air pipe by a shared control device by synchronously opening and closing the at least one gas metering valve and the at least one air metering valve with a regulating apparatus.   
     
     
         29 . The method of  claim 28 , including regulating an operating state of the at least one air metering valve as a reference variable according to an operating state of the at least one gas metering valve. 
     
     
         30 . The method of  claim 28 , including regulating the combustion gas in a stoichiometric relationship. 
     
     
         31 . The method of  claim 28 , including regulating the at least one gas metering valve according to a requirement of (a) a burner performance, (b) a furnace temperature or (c) a burner performance and a furnace temperature as a reference variable of the shared control device. 
     
     
         32 . The method of  claim 28 , including executing the opening and the closing at a stroke of at least 50 strokes/minute. 
     
     
         33 . The method of  claim 28 , including executing the opening and the closing at a stroke of at least 100 strokes/minute, up to 400 strokes/minute. 
     
     
         34 . The method of  claim 28 , including executing the opening and the closing at a stroke of at least 200 strokes/minute, up to 400 strokes/minute. 
     
     
         35 . The method of  claim 28 , including (a) initiating, by the shared control device, a sequence of strokes of an opening and closing when a lower furnace temperature is not met, (b) terminating, by the shared control device, the sequence of strokes when an upper furnace temperature is exceeded and (c) regulating, by the shared control device, burner performance by varying stoke time, stroke duration or stroke time and stroke duration. 
     
     
         36 . The method of  claim 28 , including metering air at a temperature below 70° C. via the at least one air metering valve and generating a temperature of up to 400° C. in the furnace.