Coiling mandrel and relative procedure for monitoring the condition thereof

Abstract

The present invention refers to a cooling control system of a coiling mandrel ( 102; 202; 302; 402; 502; 602 ) for metal products which comprises: an internal shaft ( 108; 308 ) with a plurality of sectors ( 109 ); an external drum which as a whole contains coaxially said internal shaft and which is circumferentially subdivided into a plurality of segments ( 104 ) arranged in a direct or indirect coupling connection with said sectors; and an internal and/or external cooling system of the mandrel The segments are movable in a radial direction with respect to said internal shaft through an axial movement of the latter, causing the consequent radial expansion or collapse of the drum. The mandrel is further provided with a group of temperature detection sensors ( 130, 132, 134, 136; 234, 236; 332, 336; 43 N; 53 N; 63 N; 3 N). A method for monitoring and adjusting the temperature of a coiling mandrel is also described.

1 . A cooling control system of a coiling mandrel for metal products originating from a hot rolling mill plant comprising:
 a coiling mandrel which comprises
 an internal shaft with a plurality of sectors; 
 an external drum which as a whole contains coaxially said internal shaft and which is circumferentially subdivided into a plurality of segments arranged in a direct or indirect coupling connection with said sectors, wherein the indirect coupling connection is realized by wedges coupled to anyone of said sectors and interposed between said segments and said sectors; 
 an internal and/or external cooling system of the mandrel; 
 wherein said segments are movable in a radial direction with respect to said internal shaft by an axial movement of the latter, subsequently to the internal shaft, causing the consequent radial expansion or collapse of the drum; and 
 wherein said mandrel is provided with 
 a group of temperature detection sensors; 
   and a control unit adapted to:
  receive temperature data measured in the mandrel, 
 and provided with an algorithm which: 
  compares said data with temperature nominal values, 
  increases, reduces or maintains constant the flow of the cooling liquid based on the difference determined between the measured value of the temperature and the target nominal value of the temperature. 
   
     
     
         2 . The cooling control system of a coiling mandrel according to  claim 1 , further comprising:
 electronics for managing said sensors; and   an electric power supply unit to feed the electronics and the temperature sensors.   
     
     
         3 . The cooling control system of a coiling mandrel according to  claim 2 , further comprising:
 (g) a telecommunicating system to permit the transmission of the measured temperature data to an external receiver.   
     
     
         4 . The cooling control system of a coiling mandrel according to  claim 1 , wherein the temperature measuring sensors are arranged in positions selected from the drum segments, the wedges, if present, the sectors of the internal shaft, the free spaces inside the mandrel and the external surface of the drum and/or combinations thereof. 
     
     
         5 . The cooling control system of a coiling mandrel according to  claim 4 , wherein the temperature measuring sensors are predominantly arranged in the free spaces inside the mandrel. 
     
     
         6 . The cooling control system of a coiling mandrel according to  claim 2 , wherein said electric power supply is selected from flywheel masses inserted at the rotational axis of the mandrel wherein the rotation of the shaft puts in rotation the flywheel mass which permits through an alternator the generation of an electromotive force, batteries, permanent magnets, Peltier elements. 
     
     
         7 . The cooling control system of a coiling mandrel according to  claim 1 , wherein the temperature measuring sensors are selected from junction thermocouples, infrared thermocouples, fibre optic temperature sensors and infrared sensors. 
     
     
         8 . The cooling control system of a coiling mandrel according to  claim 2 , wherein said electronics are configured such that said electronics comprise:
 an A/D converter to converting the data measured by the sensors from analog signals to digital signals; and   an antenna to transmit the digital signals to an external reader,   
       wherein the electronics are self-powering, and self-powering is accomplished from an action of a flywheel mass oriented in the rotational axis of the mandrel to server as an inertial electric generator or self-powering is provided from a battery. 
     
     
         9 . A process for monitoring and adjusting the temperature of a coiling mandrel by a cooling control which comprises the following steps:
 making available a cooling control system for a coiling mandrel according to  claim 1 ;   coiling a product coming from a hot rolling mill around said mandrel and simultaneous internal cooling of the mandrel;   measuring, using said temperature measuring sensors with a desired frequency, the temperature at various measurement points of the mandrel;   data processing and sending to a control unit;   comparing the measured data (T meas ) with nominal data (T n ) stored in the control unit; and   increasing the flow of the cooling liquid where the measured value is greater than the nominal value,   reducing the flow of the cooling liquid where the measured value is lower than the nominal value, and   maintaining the flow of the cooling liquid where the measured value is equal to the nominal value.   
     
     
         10 . The cooling control system of a coiling mandrel, according to  claim 9 , wherein the battery is a backup battery loaded by the action of said inertial generator.