Steel Machine Modification For Cut to length
Modification of steel machines to improve functionalityKarna Agrawal-Parmeshwar Steel Rolling Mills Pvt Ltd December 2015-April 2016
ObjectivesTo understand the problems faced in a production unit.To gain an understanding of steel manufacturing process. To understand the machines, the processes of maintenance and safeguards while working in such a heavy industry. To enhance the technological capacity and efficiency of machines.To understand the dynamics of the market and help broaden it.
the ProcessParmeshwar Steels receives raw material in the form of billets and ingots.The raw material is then melted in a furnace to make it malleable.The now malleable material is rolled by rollers into steel of the given diameter.The temperature of the newly formed may reach 400 Celsius.Steel is then cut into standard rods of 12 meters.The company does a stringent quality check; both chemical and physical.
Market changesSteel usually comes only as 12m rods.Parmeshwar Steels had been getting inquiries for different lengths of steel rods.I was required to conduct a study to determine the market for the product. I thus decided to conduct a survey in the form of a questionnaire. I had to build a list of important consumers and go to the offices of these people to conduct the survey.The response I got was favorable with 70% of the people willing to spend 10% more. Reinforcement work requires cutting and forming steel as per required structural design. For example, a small organization using 20 tonnes of steel would save 2,000$ through the proposed product. A big project could potentially save millions of dollars. The consumers wanted to save on the resultant wastage.
Can you add a line on how you carried about your market research? Was it a questionnaire? 4
I undertook a project where I aimed to cut steel to specific required sizes. To achieve this, I visited the production site all February to investigate the problem and to figure out the solution. I also planned the course of action during this month. During March, I modified the machine to suit the specified requirements. I also made some tweaks during April to make the machine more efficient.
The machineThe machine I had to modify was a shearline. The shearline is the machine which cuts steel into 12m rods. The shearline follows the following process: Roll Measure Stop Cut
The machine is designed for mass production.Variation in length was produced +- 50 mm to +- 75 mm to the size fed to the controller.The variation needed to come down to +- 5mm.
SolutionThe solution to the problem was assessed. It was decided that I needed to change the measurement device and fix a sensor plus measuring reader which can be programmed and which was accurate. Thus the existing device (which was a digital length counter with a proximity sensor) was to be replaced and the machine would have to be fitted with a single axis DRO (digital readout) with a rotary encoder.
SolutionSecondary to the DRO,1.Gear ratio had to be increased to stabilize the machine speed & reduce resultant vibration so that the encoder could correctly measure the length.2.The response time for hydraulic valves operation was sluggish. Firstly I needed to service the hydraulic control unit to achieve maximum efficiency. If the problem still persisted, I would have to change the hydraulic pump.
The PlanI devised a plan to complete the project in minimum cost and time.The plan proceeded in steps:Experimentation: I had to experiment on the machine to figure out the parts best suited for the required function. However, due to careful planning I completed experimentation in 14 days.Assembly: The assembly of the machine was done in the final week of march. The assembly had to be done quickly as the production suffered if the machine could not be used. Optmization: I optimized the machine during April. This was done to ensure maximum efficiency and speed.
RISKSAs with every project, there were some inherent risks involved. The main risks I faced during the project were:Production had to be stopped while I was modifying the machine. Thus I was given a small window to complete the assembly.The production unit was dangerous as the temperature of steel often reached 600 Celsius. Protective gear had to be worn at all times.The major risk was inexperience. As this was my first venture, there was a chance I could fail at the project.
Team workGuidance from senior professionals in field of automation, mechanical engineering & hydraulics was necessary. The following team of consultants mentored me for the project:Mr Anjal Sharma - Senior Engineer Consultant for Automation.Mr Ashok Panchal Consultant for Mechanics Mr Kishan Ambavi- Consulted for Hydraulics. Their mentorship helped me immensely and I got to learn the practical application of the theories we are taught in schools.
The Plan Process Flowchart Encoder/DRO Measure Length Accuracy
Length =5mm Yes Assembly No Exit
Project Flow1. Sensor was mounted and enclosed in its appropriate housing with proper wiring to its control(DRO)2. The original machine was observed for 12 hours to notice its perfomance.3. As we had deducted during planning & experimentation stage ,gear ratio needed to change to stabilize machine vibration which was upsetting the encoder signal. The Hydraulic Pump was also slow to respond to the electric signals from the encoder controller.First 1:1.15 ratio gear were replaced. I observed that a higher ratio would be better for accuracy and .05 increase in ratio will not harm the production much. Thus finally 1:1.2 gears were fitted.The hydraulic pump was replaced. Hose pipes for higher displacement were installed.Machine started and production resumed. Various sizes were input through the controller. And the production data was collected over a period of a month.
Key takeawaysWhile I was doing the project, I learnt a lot of things. The lessons I learnt were:Practical application of the theoretical aspects of science that we learn in school is the key to engineering.Teamwork is the key to successfully completing a given project.Good mentors contribute a lot to the knowledge an individual has.India has a dearth of modern technology and its knowledge which reduces efficiency and natural resources.A rising need for India is for it to modernize its infrastructure and production to achieve maximum efficiency.
I have changed an arising need to a rising need 14