iSixSigma

How to Find Variation in Saw-Cutting Improvement Project

Six Sigma – iSixSigma Forums General Forums Tools & Templates How to Find Variation in Saw-Cutting Improvement Project

This topic contains 3 replies, has 2 voices, and was last updated by  Mike Carnell 4 months, 3 weeks ago.

Viewing 4 posts - 1 through 4 (of 4 total)
  • Author
    Posts
  • #235683

    Aaron Olson
    Participant

    I’ve begun work on a new project.

    I was given the following problem to work on:

    A long-time part needs to be examined and cost needs to be reduced.

    Leadership observed the wastes of:
    raw inventory (we get get large shipments monthly),
    expenses in packaging,
    Occasional rework,
    etc.

    The part is essentially an aluminum tube that gets cut to length; packed in boxes; taken to our deburring station where they are tumbled, washed, and dried; then sorted (photo sorter for length and outer diameter) and repacked; then shipped.

    There appears to be some of the following quality issues:
    residue not being washed off of stock from the mill
    Dents/Scratches from pre-receiving handling
    Incomplete cuts that leave small burrs
    Short/long cuts

    The “easy” suggestion was to reduce deburring/cycle time to reduce cost.

    This, however wouldn’t appear to eliminate any paid labor, overtime, or actual processing costs. There are also no intentions to sell more product utilizing those resources currently.

    That tells me that I’d be wasting my time as it wouldn’t reduce our cost but our perceived cost. We would then pass on a cost break to our customer without actually reducing our expenses or increasing revenue. Therefore, i’m working towards increasing yield from the cutting process. This seemingly would mean actual savings in the form of raw material cost down the road.

    My assumption is that I need to begin collecting data regarding cut length, burr presence, etc. to begin to find my source of variation in those outputs. Any suggestions on further direction or what type of tests would be most effective in trying to find the source of variation?

    0
    #235713

    Mike Carnell
    Participant

    @aaronolson Just a quick story. Similar issue except cutting hose. Turns out the supplier of the hose can cut it automatically and did not increase our price. At some point in the past a person had decided if we cut we would save money. Now the supplier purchased reels to roll up the hose which was different than every other process he had. Maybe it won’t turn out as nicely as that but I would ask.

    The residue I would have the factory remove it unless it is in the spec. Change the spec but check it first to see what it says.
    Length is a capability study. Probably an MSA as well.
    Incomplete cuts maybe a tool wear issue? Is this automated?
    Dents and scratches just stand on the line (or work on it) and watch.
    Any of this goes through visual inspection then an attribute R&R. (if your job is to find scratches, burrs and dents and the process improves then the inspector thinks their job is looking harder)

    Just my opinion

    1
    #235714

    Aaron Olson
    Participant

    Thanks @mike-carnell for the response!

    We are an aluminum distributor that purchases from mills and extruders, cuts bars to precision lengths, and machine parts if necessary.

    These tubes are cut to about 2″ with a +/- .005″ tolerance. We use automatic saws to cut down from 16′ lengths.

    We have some data stored in an SPC program – I am going to have to run an MSA for sure to see if it’s usable.

    0
    #235715

    Mike Carnell
    Participant

    @aaronolson The reason I asked about the cutting operation is because if you have incomplete cuts there has to be some systemic issue in terms of an incomplete cut. If my blade travels a certain distance and over time I get incomplete cuts either the travel drifts of the blade wears down. I would start measuring the blade. Normally it wears down. Just simple stuff like that.

    Just my opinion

    0
Viewing 4 posts - 1 through 4 (of 4 total)

You must be logged in to reply to this topic.