Sheet FabricationPlet 370

Matt EuryBrian Martonik

Mike McElhaney

Objective

• To understand sheet fabrication

• Learn it’s processability

• Learn the applications

Outline

• Materials

• Processes

• Equipment

• Secondary operations

• Applications

Introduction

• Several Sheet fabrication processes

• Many materials used

• Wide range of applications

Advantages

• Light weight

• Weather Resistance

• Colors

• Good optical qualities

• High impact resistance

• Cost (glass)

Disadvantages

• Cracking

• Bubbles

• Crazing

• Low Tolerances (Cell Casting)

Materials

• Acrylic

• Polycarbonate

• Polypropylene

• Polyethylene

• Nylon

• Acetyl

Processes to Form sheets

• Cell Cast

• Continuous cast

• Extrusion

Cell Casting

• Poured between sheets of glass

• PVC gasket

• Heat process causes reaction – Good surface quality and optics– Low optical distortion

Cell Casting

• Sizes– 2 m by 3 m

• Thickness– 2 to 12 mm

Continuous Casting

• Poured between polished steel belts– Belts heat and cool material– Highest productivity – High molecular weight– Harder surfaces – Isotropic shrinkages

Continuous Casting

• Sizes

- varies

• Thickness

- 1.5 mm

Extrusion

• Resin pellets melted by extruder

• Shaped by die

Extrusion

• Sizes – Up to 4 meters

• Thickness– .25 to 15 mm

Equipment

• Auxiliary Equipment– Blenders– Screen changers – Melt Pump– Static Mixers– Texture Rolls

Equipment

– Grinders– Dryers– Feedstock

Secondary Operations

• Cutting

• Decorating

• Drilling

• Forming

• Jointing

• Finishing

Secondary Operations

• Cutting – Band Saws– Circular Saws– Knife– Laser Cutting – Water Jet

Secondary Operations

• Decorating – Printing – Painting – Stamping – Decals

Secondary Operations

• Drilling – Tapping – Hole saw– Drill bits

Secondary Operations

• Forming – Thermoforming – Presses– Clamps– Cold forming

Secondary Operations

• Jointing – Cementing – Adhesives– Dip and soak– Ultrasonic welding

Secondary Operations

• Finishing – Sanding – Filing – Ashing – Polishing

Desired Properties of sheets

• Sheet properties– Dimensions– Surface type– Orientation– Contamination

Desired Properties of sheets

– Toughness– Moisture content

Applications of Sheets

• Signs

• Picture frames

• Instrument panels

• Safety shields

• Hot Tubs

• Glass Replacement

Applications continued

Conclusion

• Great glass replacement

• Many applications

• Mass production easily accomplished