Hoppers are used for the temporary storage of materials. They are designed so that stored material can be dumped easily and delivered to the processing equipment. There are several different types of hoppers including dumpers and tippers. Other examples include bottom hoppers, live hoppers, cropper hoppers, cullet hoppers, and sludge hoppers; dump boxes, chip boxes, trash boxes, and scrap boxes; and various types of refuse equipment. Bottom hoppers are designed so that stored materials can be dumped from the bottom of the hopper. Dumpers and self-dumping hoppers are included in this category. Live hoppers or live-bottom hoppers use hydraulically or mechanically actuated augers or screws to help discharge viscous materials. Some hoppers have a base that allows them to be lifted by forklift for dumping. Others have a positive locking-latch mechanism to prevent accidental dumping. Tilt hoppers, dewatering boxes, and rotating or rotator boxes may also provide special features.

Storage bins are frequently located inside the facility to provide an in-plant surge capacity for the distribution system. This is especially true if the plant location is such that the outside environment is subject to large seasonal variations in temperature and the extrusion process requires material at a relatively consistent temperature for process stability. Inside storage bins of sufficient volume, commonly called surge or day bins, allow resin temperatures to stabilize before processing. Inside storage bins are also necessary if the system distances and throughput requirements would require the system conveying lines and pump sizes to be prohibitively large if conveying were direct from silo to destination. The inside bins are located between the silos and the distribution system and are typically loaded by a conveying system separate from the in-plant distribution system.

Hoppers differ in terms of applications and features. Some are made with the material handling applications in mind. Others are suitable for processing, recycling or handling hazardous materials.

• Plastics
• Recycling
• Material Handling

Hoppers can come in a variety of styles with some specialized features for those unique situations. Hoppers can be designed for heavy duty operation. They can be insulated, resistant to moisture, temperature controlled with special mounting methods. Other hopper designs include wheels or rollers for added portability. Other important hopper specifications include:

• Volume Capacity – the volume of material a hopper is supposed to hold.
• Weight Capacity – the weight of material that a hopper can contain.
• Depth or Length, Height, Width or Diameter – for instance, the distance from the front opening to the back of the hopper.
• Material of Construction – while most hoppers are made of plastic or metal, i.e., polyethylene, polypropylene or stainless steel and aluminum.

The LIW Loss-in-Weight hopper is suited to all extrusion processes.

• Automate material usage control for all extrusion processes
• Return on investment within 6 months
• Raw material savings up to 10%

Loss in Weight Control

• Comprehensive loss-in-weight control, monitoring live consumption rate to an extruder and updating process rate every second.
• The LIW hopper is suspended on a pair of highly accurate load cells.
• Sized according to throughput.
• Throughput of line is fully automatic and requires no user intervention.

Maguire + Syncro Syntrol Control

• Maguire + Syncro specialist extrusion control for every type of extrusion process.
• Syntrol touchscreen allows quick and easy setup of extrusion process.
• Easily set process parameters like gram/meter, micron and layer ratios.

Key Benefits of Extrusion Control

• Overall raw material savings of up to 10% compared to manual regulation.
• Reduced start-up material wastage & changeover scrap.
• Achieve faster startup times.
• Automatically regulate extruder and haul-off speeds to always be on target.
• Eliminate process variations due to screen pack, voltage fluctuations and MFI differences.
• Document clearly material usage and process parameters for quality, process and cost control.
• Return on investment within 6 months.
• Fast payback by reduced material usage, production scrap, manual intervention and increased productivity.
• Optimize process from constant extrusion control.

Range of Material

• Suited to every application of free-flowing material, pellets, granules or powder.

Rapid Access

• Magnetic retainers on the hopper enclosure allow quick access to the LIW hopper.

Audible and Visual Alarms

• Alarms are activated is system is not operating withing required process conditions.

Faster-Start up Time

• Switch from manual start-up to automatic and set required output.
• No further operator involvement.

Quick Material Release

• Optional compact drain can be mounted directly below the LIW hopper.
• Rapid draining of materials.