Matt Hrivnak

Kaizen: There's always another future state


Recently, I facilitated a kaizen event which was targeted at dramatically reducing the setup time of a Former-Winder twisting machine in a textile plant.  Naturally, we performed a SMED event; dedicating 3 days to the event and 2 days of prior videotaping (performed by me, under ‘normal’ conditions). A little background on the Former-Winder’s operation.  It is a machine that takes in raw material Yarns or Ends, twists them together into a strand, and winds them onto a 3 foot long bobbin.  The Yarns/Ends used can number anywhere from 2 and go up to 150 in some cases.  The bigger the yarn needed, the more raw material packages that will be required.  These raw material packages are put up onto fixtures, called Creels, that hold them while they feed out yarn.  The pictures show the creels in this case.

Raw material creel 

After loading the creels, the operator needs to install gearing that produces different levels of twist in the finished strand.  Creating a small sample allows the operator to perform a quick in-process check after changing the gears.  If it is okay, the operator puts in an empty bobbin and starts the machine.  If not, then he changes gears with engineering’s help (that’s what the ISO documentation says at any rate). Watching the video we put together this timeline, identifying the CURRENT STATE (i.e. the way in which it was currently being performed)External Setups in GREEN and the Internal Setups in RED:

  • Get & read traveler (1 min.)
  • Check prioritization (1 min.)
  • Get gears (15 min.)
  • Install gears (5 min.)
  • Return gears to proper place (1 min.)
  • Clean/grease machine (5 min.)
  • Program computer (if necessary) (1 min.)
  • Obtain/order material (45 min.)
  • Creel placement (20 min.)
  • Create material space (10 min.)
  • Get/prepare cart (if necessary) (1 min.)
  • Teardown (16 min.)
  • Return material (several trips) (9 min.)
  • Prepare & inspect creel (foam donuts, check eyelets, inc.) (2 min.)
  • Check for/install small packages (10 min.)
  • Get/install new packages (several trips) (22 min.)
  • Untie packages & feed thru eyelets (38 min.)
  • Setup distribution plate(s) (13 min.)
  • Setup wax tank (if necessary)
  • Locate & get proper die (5 min.)
  • Install die (1 min.)
  • Return old die to proper place (1 min.)
  • Feed machine (6 min.)
  • Run (.5 min.)
  • Chalk for twist (TPF) (.5 min.)
  • Stop & check TPF (.5 min.)
  • Sign off by other person (.5 min.)
  • Make adjustments (6.5 min.)
  • Run (couple minutes)
  • Stop & calculate weight/counts (repeat if necessary)
  • Check traveler for QTY (.5 min.)
  • Run Machine

—————————————————

76% Internal:  179 min = 2.98 hours

24% External:  58 min = .97 hours

Total Time:   237 min. = 3.95 hours

We then went through this list and created a ‘theoretical’ best case scenario that showcased the true Internal and External Setups.  Some of these are not even possible due to current technologies owned by the company:

  • Get & read traveler (1 min.)
  • Check prioritization (1 min.)
  • Get gears (15 min.)
  • Install gears (5 min.)
  • Return gears to proper place (1 min.)
  • Clean/grease machine (5 min.)
  • Program computer (if necessary) (1 min.)
  • Obtain/order material (45 min.)
  • Creel placement (20 min.)
  • Create material space (10 min.)
  • Get/prepare cart (if necessary) (1 min.)
  • Teardown (16 min.)
  • Return material (several trips) (9 min.)
  • Prepare & inspect creel (foam donuts, check eyelets, inc.) (2 min.)
  • Check for/install small packages (10 min.)
  • Get/install new packages (several trips) (22 min.)
  • Untie packages & feed thru eyelets (38 min.)
  • Setup distribution plate(s) (13 min.)
  • Setup wax tank (if necessary)
  • Locate & get proper die (5 min.)
  • Install die (1 min.)
  • Return old die to proper place (1 min.)
  • Feed machine (6 min.)
  • Run (.5 min.)
  • Chalk for twist (TPF) (.5 min.)
  • Stop & check TPF (.5 min.)
  • Sign off by other person (.5 min.)
  • Make adjustments (6.5 min.)
  • Run (couple minutes)
  • Stop & calculate weight/counts (repeat if necessary)
  • Check traveler for QTY (.5 min.)
  • Run Machine

—————————————————

11% Internal:  26.5 min = .44 hours

89% External:  210.5 min = 3.51 hours

 

This gave us a starting point for base lining and making improvements.  “How could we improve our current setup process to be as close to this as possible?”  First, we took all of the ‘current’ internal setups that were really external setups, and made them into external setups, changes shown in BLUEThis saved about 25%:

  • Get & read traveler (1 min.)
  • Check prioritization (1 min.)
  • Get gears (15 min.)
  • Install gears (5 min.)
  • Return gears to proper place (1 min.)
  • Clean/grease machine (5 min.)
  • Program computer (if necessary) (1 min.)
  • Obtain/order material (45 min.)
  • Creel placement (20 min.)
    • Preparation (10 min.)
    • Physical move (10 min.)
  • Create material space (10 min.)
  • Get/prepare cart (if necessary) (1 min.)
  • Teardown (16 min.)
  • Return material (several trips) (9 min.)
  • Prepare & inspect creel (foam donuts, check eyelets, inc.) (2 min.)
  • Check for/install small packages (10 min.)
  • Get/install new packages (several trips) (22 min.)
  • Untie packages & feed thru eyelets (38 min.)
  • Setup distribution plate(s) (13 min.)
  • Setup wax tank (if necessary)
  • Locate & get proper die (5 min.)
  • Install die (1 min.)
  • Return old die to proper place (1 min.)
  • Feed machine (6 min.)
  • Run (.5 min.)
  • Chalk for twist (TPF) (.5 min.)
  • Stop & check TPF (.5 min.)
  • Sign off by other person (.5 min.)
  • Make adjustments (6.5 min.)
  • Run (couple minutes)
  • Stop & calculate weight/counts (repeat if necessary)
  • Check traveler for QTY (.5 min.)
  • Run Machine

—————————————————

57% Internal:  134.5 min = 2.24 hours

43% External:  102.5 min = 1.71 hours

So, after a few hours of suggestions, some time working the setup process on the gemba, we were able to make a second pass, saving around 72%!  We designed a new creel that could have one side loaded with the current job and a second side that could be prepared for the next job.  This required a 30 day list be made up and completed because of the nature of the maintenance work needed and a few other action items that were external to the SMED event itself:

  • Get & read traveler (1 min.)
  • Check prioritization (1 min.)
  • Get gears (15 min.)
  • Install gears (5 min.)
  • Return gears to proper place (1 min.)
  • Clean/grease machine (5 min.)
  • Program computer (if necessary) (1 min.)
  • Obtain/order material (45 min.)
  • Creel placement (20 min.)
    • Preparation (10 min.)
    • Physical move (10 min.)
  • Create material space (10 min.)
  • Get/prepare cart (if necessary) (1 min.)
  • Teardown (16 min.)
  • Return material (several trips) (9 min.)
  • Prepare & inspect creel (foam donuts, check eyelets, inc.) (2 min.)
  • Check for/install small packages (10 min.)
  • Get/install new packages (several trips) (22 min.)
  • Untie packages & feed thru eyelets (38 min.)
  • Setup distribution plate(s) (13 min.)
  • Setup wax tank (if necessary)
  • Locate & get proper die (5 min.)
  • Install die (1 min.)
  • Return old die to proper place (1 min.)
  • Feed machine (6 min.)
  • Run (.5 min.)
  • Chalk for twist (TPF) (.5 min.)
  • Stop & check TPF (.5 min.)
  • Sign off by other person (.5 min.)
  • Make adjustments (6.5 min.)
  • Run (couple minutes)
  • Stop & calculate weight/counts (repeat if necessary)
  • Check traveler for QTY (.5 min.)
  • Run Machine

—————————————————

21% Internal:  49.5 min = .825 hours

79% External:  187.5 min = 1.71 hours

We looked heavily into streamlining the leftover Internal Setups and determined that most of the streamlining had already been done. These machines (literally, these same machines) had been working in this plant since the 1940s and people had come up with quicker and better ways of doing things in that time.  Of course, we are still working towards streamlining and looking for those opportunities daily.

So, some team work, some more aware operators and better methods will allow us to service the internal customers of this process a lot faster, in the exact quantities they need and that means we can service a much greater variety of product lines within the same timeframe as before!

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