×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

hollowcore slabs (slipforming and extrusion)
2

hollowcore slabs (slipforming and extrusion)

hollowcore slabs (slipforming and extrusion)

(OP)
Hello everyone
I would like to know if someone can explain me the differenece between slipforming and extrusion production of precast hollowcore slabs.

Thank You

RE: hollowcore slabs (slipforming and extrusion)

Slipforming, I believe, involves the concrete placed in bulk in front of a moving vibrator/screed that maneouvers the concrete into place.  In this method, the hollow cores are simply formed in place prior to depositing the concrete.  The concrete stays in place and the form moves over it.

Extruded - the concrete is pressure injected through a non-moving form pattern that replicates the cross section of the hollow core plank.  The concrete is mixed to a low enough slump to maintain its shape.  The form stays in place and the concrete moves along a guide conveyor.

RE: hollowcore slabs (slipforming and extrusion)

The Hollowcore guy I talked to last week called their process "extrusion" but then described it like JAE mentioned above. It's really more of a slipforming than a true extrusion. They place a very very stiff mix over a rotating auger which tapers down into a solid mandrel. The mandrel OD matches the core ID. The machine travels along the 400' long bed and lays the finished slab behind it as it goes. After a surprisingly short cure time, they saw the 400' pieces into custom lengths and, viola, a slab is born.     

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close