×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Reducing plastic waste at sheet extrusion company

Reducing plastic waste at sheet extrusion company

Reducing plastic waste at sheet extrusion company

(OP)
We are sheet extruder and we generate about 10% waste through edge trim and floor sweeps and purgings. we do recover about 5% by grinding the edge trims and putting back in the blends. But it still adds grinding time, reprocessing costs and machine hr cost. I want to know how some have overcome these? also how to avoid lot of floor spills and die purgings which account for almost $400 a week.

Thanks

RE: Reducing plastic waste at sheet extrusion company

well if you are purgin for color changes or your materials are expensive you could use a purging compound.  as far as floor spills what exzactly are you talking about, guys dumping materil on the floor or what. you could get a material handling system.  more info

RE: Reducing plastic waste at sheet extrusion company

Your question is very general.

The very general answer is optimise your process and improve your materials handling and housekeeping.

I guess you control the width before trimming by extruder output and roller speed and pressure or clearance settings. If so reducing extruder output and roller pressure will reduce edge waste. If the rollers are set gap rather than pressure, leave the gap but reduce output.

If you overdo this, you will end up with 100% waste rather than less than 5%.

re purgings, careful attention to production scheduling and correct technique are possibilities. Also, the screw and barrel clearance should not be excessive and the die and die plate should have no hang ups. A sheet or so called Coat Hanger die should be pretty straight forward and if in good condition should not be a problem.

You may need to remove the die face for major colour change purgings. If you remove the dieface, use a gas torch to burn out any material on it.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.

RE: Reducing plastic waste at sheet extrusion company

You might try to control the width by using a restrictor bar in the outside lip of the extruder and turn off the heats to the restricted zones to run a narrow sheet if the full width isn't required.
 The time involved and the readjustment of the puddle can take some time, so it would only be feasable on a lengthy run.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources