Storage Hopper and Mass Flow Screw Feeder for Shredded Polypropylene and Fiberglass

General Description

Hanwha Azdel is a global leader in the manufacture of light weight reinforced thermoplastic composites for the auto industry. Most of the composites are used for interior and exterior components for autos, heavy trucks and other transportation vehicles. The composites are ideal for thermoforming sheets into complex shapes.

To expand production, Hanwha Azdel needed to greatly increase storage capacity of recycled polypropylene and fiberglass at their facility. Thermoplastic boards consisting of approximately 50-percent polypropylene and 50-percent fiberglass were being shredded into fine particle sizes and then pneumatically conveyed to a storage hopper. Hanwha Azdel contacted KWS to engineer and manufacture a 2,600 cubic foot hopper with live bottom screw feeder.

Design Parameters

1. Product Type: Recycled Polypropylene and Fiberglass
2. Material Density: 20 Lbs. per Cubic Foot
3. Capacity: 250 Cubic Feet per Hour
4. Duty: 24 Hours per Day, 7 Days per Week

KWS Advantages

Engineers from Hanwha Azdel contacted KWS after reviewing the KWS website and qualifying KWS as a partner capable of solving their bulk flow issues. Utilizing 3D parametric modeling, KWS provided a layout of their new production facility as the large hopper towered at a height of just over 21-feet. KWS designed the new hopper in small sections for easy installation in field, which would allow Hanwha Azdel to utilize cranes existing in the new facility by not exceeding load limits.

KWS has extensive knowledge and experience with light density bulk materials such as polypropylene and fiberglass. Light density bulk materials can be difficult to store and meter due to bridging and ratholing. KWS designed the hopper and screw feeder using proven mass flow technologies.

Special Features

The new KWS hopper was designed for a usable capacity of 2,600 cubic feet and for mass flow of the polypropylene and fiberglass using a twin-screw feeder. Mass flow of bulk materials is important for process success. Mass flow creates a “first in-first” out uniform flow with no bridging or ratholing. The sloped walls of the hopper were designed at 60-degrees to ensure uniform flow. Each side wall panel was manufactured for easy shipment and installation.

A leveling screw was located at the top of the hopper so bulk materials could enter on one side and be conveyed to the opposite side for maximum storage capacity.

The twin-screw feeder was equipped with a mass flow cone to provide even draw of bulk materials the full length of the opening. The twin-screw design creates a wider inlet opening to eliminate any bridging that may occur. KWS Mass Flow Screw Feeders use a combination of varying inside diameter and pitch in order to ensure a consistent flow along the entire length of the inlet. A feeder shroud accurately controlled the discharge rate. KWS also provided individual high torque drives so the twin-screw feeder could start up under a full head load of material in the hopper.