Associated Plasmatron Pvt Ltd

  • To enhance the capacity and utilization of Conventional Innocenti Lathe machine for pre and post coating operations through innovation and automation.
  • Water cool roll received from competitor for coating having dimensions of ɸ 1600mm and L 1900mm (Ref no: 14727 Dtd : 09/10/2016) (Fig. 2.1)
  • We already had an upper edge over our competitors in terms of coating capabilities. Having an in-house machining set up would have enabled us to be more competitive for new manufacturing orders and turnkey projects.

Fig. 2.1

  • Order confirmation from customer for coating and polishing of steel mill roll having ɸ 1500mm and L 2200mm (Ref no: VJNR/112973/REF/R/4500062006 Dtd: 25/02/2017. Job received on 07/03/2017)
    • We had capability to do coating of such big sized rolls but pre-coating operations such as coating removal, pre-machining and post-coating operations such as polishing and super-finishing had to be outsourced.
  • Implications of outsourcing a roll with ɸ 1500mm and L 2200mm
  • Regular enquiries for diamond polishing of rolls greater than ɸ 1000mm.
  • Market Potential – As per feedback from JSW Bellary around 70 rolls of ɸ above 1000mm are installed in one plant out of which 50% have specialized coating. Each established steel mill has the same requirement of rolls. Therefore, considering 35 installed coated rolls in one plant and considering total of 10 steel mill plants we can further evaluate:
    • New Manufacturing – Avg. value Rs. 8L per roll. 8 x 18 x 10 = 14.4 Cr
    • Job Work – Avg. value Rs. 3.5L per roll. 3.5 x 25 x 10 = 8.75 Cr
    • Repair – Avg. value Rs 5L per roll. 5 x 18 x 10 = 9 Cr
    • Total Market Potential Per Annum – 32.15 Cr
  • Option 1
    • Buy New Machine
      • Heavy Duty machines of such size is not manufactured in INDIA
      • To meet our requirement, the machine will have to be custom made and imported. An approximate cost of Conventional Heavy Duty machine with a size of ɸ 1800mm and L 5000mm will cost around Rs 2 Cr (*This is just an indicative value covering cost of machine, freight, import duty and custom clearance, commissioning and training etc.)
      • Turn around time from Order to delivery of the Machine
    • Buy Second hand machine
      • Availability of machines as per required size is very rare
      • Approximate cost of machine was around Rs 50 lakhs
      • Turn around time from Order to delivery of the machine and customisation.
  • Option 2
    • Upgrade/Modify existing machine
      • Two conventional lathe machines in existing setup were identified based on requirement
      • Indian make machine – Rajendra Lathe
        • Machine Dimensions: Turning ɸ – 600mm, Swing Over ɸ – 800mm, Between centre length – 5000mm
        • Lack of rigidity of construction of bed and tailstock – Necessary for proper clamping and rotation of job
        • Spindle was belt driven - Not suitable for turning operation
      • Italy make machine – Innocenti Lathe
        • Machine Dimensions: Turning ɸ – 750mm, Swing Over ɸ – 1000mm, Between centre length – 6000mm (Fig. 3.1)
        • Rigid construction of machine bed and tailstock – Essential for load carrying capacity and support
        • V and Flat guideways were bigger in size – Better clamping and support
        • Spindle was gear driven - Turn heavy job easily
        • There was positive locking to tail stock base – Ensure better safety during turning operation
        • Spindle was having rigid bush bearings – Better load carrying capacity. Extended life of spindle bearing

  Fig. 3.1

  • Based on the above assessment, Option 1 was discarded as the investment cost was very high and would have a longer ROI period.
  • Option 2 was selected and it was decided to increase the swing over diameter of Italy make Innocenti conventional lathe machine by adding Cast Iron distance blocks to the Head stock and Tail stock and replacing the X-axis slide with new cast iron slide.
  • Dismantled the entire machine
  • Took dimensions of head stock, Tail stock and X axis slide for making casting patterns and casting moulds.
  • Casting was outsourced to Vishal Casting - Pune
  • Entire machine scrapping was done by outsourced vendors on labour basis.
  • Bush scrapping of the spindle for correction of spindle run-out.
  • Machining of casted moulds as per required dimension of Head stock, Tail stock and X-slide (Fig. 4.1/4.2/4.3)

  Fig. 4.1  Fig. 4.2  Fig. 4.3

  • Servicing of entire Head stock assembly, Feed gear box assembly, Apron gear box assembly for eliminating mechanical issues.
  • Manufacturing of new lubrication system (Fig. 4.4) to get below benefits:
    • We added pressure switch (Fig. 4.5) to check spindle lubrication pressure continuously. Faulty lubrication will raise an alarm (Fig. 4.6) and protect the entire Head stock assembly.
    • We added inline filtration system to remove dust from lube oil to protect the Head stock bearings.
    • We make separate tank of 30 L capacity for heat dissipation to increase productivity and reduce unexpected downtime

  Fig. 4.4  Fig. 4.5  Fig. 4.6

  • Provided separate lubrication pump for Apron gear box assembly. (Fig. 4.7)
  • Provided centralized lubrication system for X and Z axis slide. (Fig. 4.8)

  Fig.4.7  Fig. 4.8

  • We decided to convert CONVENTIONAL machine to SMART machine.
    • Smart machine means,
      • The electrical system will continuously monitor its peripheral Lubrication pressure, Oil level, Operating current etc.
      • If there will be any fault in machine, system will automatically generate an alarm for same. (Fig 4.9)
      • As per interlock written in PLC logic, machine will not run until clear of an alarm.

(Fig 4.10)

  Fig. 4.9  Fig. 4.10 

      • Machine will take care of itself thereby reducing time and cost for Autonomous and Preventive maintenance.
  • New Electrical panel and Field wiring to avoid any electrical breakdowns.
  • Incorporated VFD for spindle motor drive (Fig. 4.11) for smooth start and stop by ramp up and ramp down function of VFD. This eliminated possibility of damage to the job by immediate jerking. This also help to increase life of machine head stock assembly.

  Fig. 4.11  Fig. 4.12  Fig. 4.13

  • Servo motor drive for X and Z axis feed which enabled minimum feed setting for big diameter jobs. (Fig. 4.12)
  • Converted conventional contactor and relay logic with latest PLC logic due to which wiring complications where minimized and better process interlocking was achieved. (Fig. 4.13)
  • HMI (Human Machine Interface) for easy diagnosis, Spindle R.P.M. input, X and Z axis feed input, alarm display and diagnosis of faults easily by checking I/O of system. (Fig.4.14/4.15)

 Fig. 4.14  Fig. 4.15 

  • We have taken most possible faults in systems like (Fig.4.16)
    • MPCB trip faults
    • Spindle lube pressure fault.
    • Centralised lube oil level fault
    • Centralised lube oil pressure fault.
    • Spindle drive VFD faults.
    • Servo motor driver faults etc.  Fig. 4.16 
  • Two operator panels for ease of operation. One on Head stock assembly and another on X axis slide. (Fig.4.17/4.18)

 Fig. 4.17 Fig. 4.18

  • Remote pendant for spindle jog operation. (Fig.4.19)
  • Tower lamp on machine for remote monitoring of machine status.
  • Male-Female SMC connector for coolant pump supply enabled easy cleaning of coolant pump. (Fig.4.20)
  • Male-Female SMC connector for easy dismantling of machine for maintenance purpose. (Fig.4.21)

 Fig. 4.19 Fig. 4.20  Fig. 4.21 

SR.NO Risks Identified Mitigation
1 Load carrying issue of spindle drive as compared to job.
  1. Machine head stock is rigid and all geared type drive.
  2. Metric 100 type spindle taper bore, resulting in increase in spindle strength.
  3. Spindle drive motor 40 HP
2 When we increased centre height, X and Z axis feed drive was disconnected.
  1. Rather than provision of gear train for feed of X and Z axis we provided independent servo drive.
3 Slippage of tailstock while turning heavy rolls
  1. There is a positive locking arrangement for tail stock to avoid slip while machining.
4 Chances of spindle drive failure due to contamination in spindle lube oil.
  1. Incorporated inline filtration system to avoid such issues.
5 Wear and tear of X and Z axis slide due to lack of lubrication
  1. Provided float switch to monitor oil level of lube system.
  2. Provided pressure switch to check lube pressure.
6 Starting torque on machine head stock drive while turning heavy job
  1. Incorporated VFD for spindle drive. To eliminate starting torque on mechanical drive.
1 Entire machine dismantling, servicing and assembly. In-house automation and maintenance team. -
2 Entire machine panel and field wiring. In-house automation and maintenance team. -
3 Entire machine scrapping External vendor (Chennai) 3,50,000 INR
4 Cast iron mould pattern and moulding Vishal casting (Pune) 2,50,000 INR
5 Cast iron mould machining Local vendor 1,50,000 INR
6 Spindle lubrication system and centralised lubrication system Lubrotech Engineers (Mumbai) 50,000 INR
7 Mechanical Material Local Suppliers 1,50,000 INR
8 Electrical Material DS Electricals 3,00,000 INR


  • Enhanced existing machine turning capability from 750 mm to 1500 mm diameter. (Fig. 5.1/5.2)

  Fig. 5.1 Fig. 5.2 

  • Restored machine geometrical accuracy within 0.1mm.
  • Ability to do turning, polishing and re-centring operations on same machine.
  • No need for outsourcing. All operations could be done in-house leading to cost saving, prompt deliveries and better quality control.
  • Increased chances of winning customer orders through capability and competitiveness


1 Machine Full Load Current. 50 A
Rs. 181 per Hr Electrical Running cost * 638 Working Hrs
Rs. 1,15,478/-
20 A
60% Reduced Electrical Consumption -Rs. 46,191/-
Electrical Saving Rs. 69,286/-


  • Turning of max diameter of up to 2000 mm in house.
  • Increased job opportunities.
  • Outsourced operations eliminated.
  • Operator dependency reduced as turning and polishing being done on same machine.
  • Setup Time reduced by 20%,
  • Operating Fatigue reduced due to automation and HMI Interface
  • Enhance geometrical accuracy of machine.
    • Taper over total Length – 0.1mm
    • Spindle Runout – 0.03mm Max
    • Axial Play – 0.03mm Max.
  • Zero Rework or Rejection till date
  • COST
  • We could save cost of pre-machining and polishing. As in-house development of machine.
  • Outsource Operation Cost Saving – Rs. 3,75,000/- per annum
  • Setup Time cost Saving – Rs. 95,250/- (127 Hrs Setup Time reduced* Rs.750/Hr Machining cost)
  • Return on Investment (ROI)
    • ROI Period – Less than 6 Months
  • On time delivery of job as in-house machining and polishing facility.
  • We incorporated all interlock in machine to avoid any accidents.
  • Zero Accident till date.
  • Operator friendly operation of machine (Use push button operating system rather than operating lever)
  • Easy for diagnosis of faults as particular alarms displayed after accruing of faults.


  • Appreciation Letter from JSW, Ballari.
  • Repeat orders from JSW.
  • Following is the customer list added due to increase in capacity:
    • Siemens Ltd, Indfab, Ruhfus India, CMI FPE.


  • We can deploy same technique to another horizontal lathe which is Russian make Conventional Lathe Machine.

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