PERANCANGAN MANIPULATOR ROBOT UNTUK PROSES POST WELD HEAT TREATMENT PADA PERBAIKAN KOMPONEN DART BESI COR KELABU DENGAN METODA FLAME SPRAY

• Main Author: Kulukussabiri, Priyadi
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/5444
• Institution: Institut Teknologi Bandung

<b>ABSTRACT:</b><br> <br /> DESIGN OF ROBOT MANIPULATOR TO PERFORM <br /> POST WELD HEAT TREATMENT IN FLAME SPRAY OF <br /> GRAY CAST IRON COMPONENT REPAIR <br /> By <br /> <br /> Priyadi Kulukussabiri <br /> NIM. 23103 002 <br /> <br /> Defects such as crack, inclusion, blow holes and porosity are often found on the casting products of gray cast iron such as machine block and cylinder head. Besides that, it's often found damages on that component due to operational cycle. Surface defects or damages are allowed to repair. There are several methods to repair gray cast iron component. One of them is flame spray welding. Either shrinkage, the disadvantages of this method are forming of white cast iron and martensite structure then followed by fissures in heat affected zone (HAZ), which allowed the component become brittle and easily crack. To prevent the forming of white cast iron, post weld heat treatment must be applied, followed by controlling of cooling rate. The critical cooling rate in the range temperature of 1200 °C to 900 °C is 2.9 °C / 10 seconds. <br /> <br /> Starting from simple basic idea that in oxy-acetylene welding, the amount of effective heat input from flame to the surface is affected by the torch's tip to surface distance. This phenomenon can be utilized to do post weld heat treatment and controlling of cooling rate by varying the heat flux or varying the distance of torch's tip to the surface in practically. The temperature changes of specimen due to the effects of varying heat input either in ramp or step are analized by finite element method software MSC Nastran. Thus for pre-heat temperature of To = 500 °C, are found that the temperature response due to step input can be represented by second order equation with the characteristics of C.= 0.63 and cry, as 0.04 Hz = 0.25 rad/sec. <br /> Based on those parameters and responses, the close loop control system is build which utilizing infra red thermometer as the sensor. A device such as single axis robot arm is designed to perform of varying the tip to surface distance. Thus monitoring and controlling cooling rate in order not to exceed the critical cooling rate can be do automatically then the repeatability of good quality would be achieved. <br />