Forming different plastic products from a single melt

Patent metadata

Field	Value
Publication number	US-9908276-B2
Application number	US-201214366576-A
Country	US
Kind code	B2
Filing date	Nov 28, 2012
Priority date	Dec 31, 2011
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

Systems ( 200 ) and methods for making different plastic products ( 202, 204 ) in a single melting process are provided. A method includes melting a plastic resin in a first extruder ( 104 ) to form a melt ( 106 ) and transferring at least a portion of the melt to a second extruder ( 114 ). Any portion of the melt ( 106 ) that is not transferred to the second extruder ( 114 ) is formed into a first plastic product ( 202 ). Additives ( 116 ) are blended with the melt in the second extruder to form a second melt ( 118 ), and a second plastic product ( 204 ) is formed from the second melt ( 118 ).

First claim

What is claimed is:

1. A system for forming different plastic products from a single melt, comprising:
a main extruder system, comprising:
a main extruder configured to melt a plastic resin, forming a melt;
an additive system configured to feed an additive to the melt in the main extruder;
a first die positioned downstream from the main extruder
a second product extruder system comprising a second product extruder that is located downstream of the main extruder;
a diverter valve positioned downstream from the main extruder and between the main extruder and the first die and the second product extruder, the diverter valve configured to:
receive the melt from the main extruder;
transfer a first portion of the melt to the first die to form a first plastic product and
transfer a second portion of the melt to the second product extruder;

and

the second product extruder system, comprising:
the second product extruder configured to blend the second portion of the melt with an additive, forming a second product melt;
an additive feeder configured to feed the product additive to the second product extruder; and
a second die configured to form a second plastic product from the second product melt; wherein the second product extruder has a capacity that is about 75% or less than the capacity of the main extruder.

2. The system of claim 1 , wherein the diverter valve is configured to transfer additional portions of the melt to each of a plurality of product extruders.

3. The system of claim 1 , wherein the second product extruder has a capacity that is about 50% or less than the capacity of the main extruder.

4. The system of claim 1 , wherein the second product extruder has a lower power demand than the main extruder for an equivalent amount of material.

5. The system of claim 1 , wherein the main extruder system further comprises a melt pump.

6. The system of claim 1 , wherein the second product extruder system does not comprise a melt pump.

7. The system of claim 1 , wherein the first or second die comprises a pultrusion pipe die.

8. The system of claim 1 , wherein the first or second die comprises a sheet die, a film die, or a combination sheet/film die.

9. The system of claim 1 , wherein the first or second die comprises a blown film die.

10. The system of claim 1 , wherein the additive feeder comprises a liquid injection system.

11. The system of claim 1 , wherein the additive feeder comprises a melt pump feeder.

12. The system of claim 1 , comprising a third product extruder system comprising:
a third product extruder that is located downstream of the diverter valve and configured to blend a third portion of the melt with a product additive, forming a third product melt;
an additive feeder configured to feed the product additive to the third product extruder; and
a third die configured to form a third plastic product from the third product melt.

13. The system of claim 1 , wherein the diverter valve is coupled to a piston and an actuator to control a flow rate of the first portion of the melt from the diverter value and to control a flow rate of the second portion of the melt from the diverter valve.

Assignees

• Univation Tech Llc

Inventors

• Abe Daudi A
• White Simon J

Classifications

• B29C48/40

  using two or more parallel screws {or at least two parallel non-intermeshing screws}, e.g. twin screw extruders · CPC title

• B29B7/7485 Primary

  with consecutive mixers, e.g. with premixing some of the components · CPC title

• B29C48/387

  using a screw extruder and a gear pump · CPC title

• B29C48/10

  flexible, e.g. blown foils · CPC title

• B29K2105/0005

  containing compounding ingredients (releasing, lubricating or separating agents B29C33/56, fibers B29K2105/08, B29K2105/12; fillers B29K2105/16, recycled material B29K2105/26) · CPC title