Remote Resin Inventory Management in the Plastics Industry

Garner Industries is a plastics molder, and is also a manufacturer of the BinMaster line of level measurement sensors and inventory management systems.

The company’s molding customers can remotely manage their resin inventory from a phone, PC, or tablet for real-time monitoring.

Real-time management of expensive resins helps ensure a continuous supply of raw materials for our operation that runs 24/7.

Our largest molding customers want visibility of their inventory so they can buy smart and reduce carrying costs of expensive resins. We found a solution right under our own roof with a BinMaster inventory management system.

Dan Hurtz, Plastics Manager, Garner Industries

Garner Industries has experienced many changes since its inception as a local tool and die shop in 1953. A decade later, BinMaster came into action when a local seed producer approached the company to design and produce a high level alert for its seed bins.

A simple mechanical switch was the starting point of the level control business, which is still a workhorse today. Garner Industries acquired a small, local injection molding operation in 1993, which has now grown to 29 molding presses. With a 75,000-square-foot facility and a press capacity range of 35-500 tons, Garner now caters to the needs of projects and companies, both small and large.

Late last year, Garner Industries significantly invested in its operation to address the needs of many of its largest customers. The company had three smooth-walled steel silos built to eliminate the need to store huge amount of gaylords full of resin in its on- and off-site warehouses.

The silos have a very deep cone to allow resin pellets to flow freely to the silo output. From the silos, the resin is pneumatically transferred to large surge bins within the plant that feed the three new 500-ton molding presses.

Eliminating gaylords is advantageous to customers as they can buy resin in bulk in truckload deliveries. Procuring the resin in truckload deliveries minimizes costs and packaging waste. The use of silos for resin storage allows the inventory to be monitored by automation instead of by physical counts. The efficiency is increased due to the reduction in the amount of handling in the factory that was carried out physically transferring gaylords of material.

BinMaster’s been making point level indicators for almost 60 years. We were also one of the first companies to introduce integrated inventory management sensors and software.

BinMaster has been installing inventory systems at plastics molders and resin manufacturers for decades. It was time to take our own system for a spin.

Doug Hartzell, Engineering Manager, BinMaster

Point Level Indicators Prevent Resin Outages and Overfills

As the Hippocratic oath goes, “First do no harm.” Point level controls are standard measures used to avoid wasting material by overfilling a silo or running out of material in a silo. The first step was to install a BinMaster VR-21 vibrating rod on each resin silo for low level control.

An automated alert is sent by them when the resin levels become low and the inventory needs to be refilled. These point level controls are placed roughly halfway up the 11.5’ hopper section of the silos.

A standard vibrating rod is used in the cone of the surge bins to alert when resin levels are low.

Each silo features a BinMaster VR-41 extended vibrating rod that is roof mounted in a 1½” coupling for high level control. The rigid extension reaches 4 feet down into the silo to compensate for the angle of repose of the material and the capacity of the silo as it is emptied and filled.

The vibrating rods are coupled to a multi-input annunciator panel for both low and high level indication. Based on the location of the sensor, the alert will help to prevent outages for the low level indicators and overfills for the high level indicators. The point level system also features an external horn to alert a truck driver if a high level during the filling process.

A VR-21 vibrating rod is also equipped to each surge bin to alert when the surge bin level is nearly empty. In order to ensure continuous operation, the point level indicator provides an alert when additional resin needs to be conveyed from the silos to the surge bins. As a result, cycle times are maximized and the presses are allowed to run continuously without any downtime.

Automated Inventory Management with Customer Visibility

A BinMaster 3DLevelScanner is mounted on top of each resin silo for inventory management. The 3DLevelScanner non-contact sensor uses acoustics-based technology to measure and map multiple points on the surface of the resin in the silo, enabling detection of surface variations, such as cone up and cone down.

The data is then processed to determine the inventory volume, that takes into account surface variations and reports a percentage full based on a weighted average of the measurements.`

A 3DLevelScanner non-contact sensor mounted on the silo roof continuously measures the level of resins in the silo.

As inventory data is proprietary to each individual customer, each system is provided with security parameters to facilitate visibility for only the resins and silos belonging to a specific customer. Also, Vendor Managed Inventory provides each customer with the option to allow its resin vendor to monitor the silos.

Garner Industries has the ability to monitor all silos and work in close collaboration with each customer to ensure the optimization of their inventory based upon upcoming demand.

Three new 500-ton molding presses are robotically equipped.

One of the silos employs the 3DLevelScanner by coupling to a conventional 4 to 20 mA signal into an Ethernet gateway. In the other two silos, an Ethernet Gateway is used for control, but the 3DLevelScanner is used in Modbus RTU mode and is daisy-chained with RS-485 wiring.

The 4 to 20 mA signal or Modbus registers are periodically sampled by both Ethernet gateways to record the levels of resin read by each sensor. The BinView web application is then used to send these resin level readings to a cloud-based database for inventory reporting. Both local and remote users have access to view current inventory levels and produce historical reports on resin use by logging into the BinView website.

The VR-21 vibrating rod alerts to low levels in surge bins.

With an Internet connection, the BinView web application can be accessed through a PC, tablet, or smartphone. It is possible to set usage alarms to notify customers of silo activity or set low or high alert alerts through text message or email.

The ability to access inventory data from anywhere allows Garner Industries and its customers to ensure a continuous resin supply to fulfill production demands. Although not used by existing Garner customers, the MV model 3DLevelScanner installed on these silos also provides PC software with an optional visualization tool to create an image representing the topography of the resin surface.

Plastics manager Dan Hurtz views inventory levels using BinView on a PC in his office.

By considering level variations in the silo, a very accurate volume estimate can be obtained using the advanced firmware provided with the sensor. It is possible to configure the software to determine the number of resin pounds contained in each silo by allowing for compaction as the resin get closer to the cone, and entering a bulk density for the material.

For inventory monitoring, the software reports low, average, and high level and calculates inventory volume depending on the material and silo parameters entered into the software.

Wireless gateways eliminate long spans of wiring through the plant.

An Automated Tape Measure Eliminates Climbing

One silo is equipped with a SmartBob II level sensor, which is a conventional weight and cable-based sensor working like an automated tape measure, but without the need to climb the silo to make measurements. This sensor is networked to BinMaster’s Binventory PC software installed on a centrally located PC via a local area network (LAN). The sensor is connected to the PC via an Ethernet to serial converter.

The features of the Binventory PC software are very similar to the cloud-based application BinView, but Binventory is installed locally on the Garner LAN rather than being hosted in the cloud, providing users with the same ability to access the software, check inventory levels, create reports, and generate usage alarms that can alert them about silo activity via email.

A wireless Ethernet radio system is also used by the inventory management system, providing factory-wide access to the inventory management tools without the need to use an industrial PC or any other data output device at the silo. As a result, more flexibility is available for connectivity to different devices and sensors, and the system can be scaled up by adding more silos and sensors to the network.

We talk to customers in the plastics industry every day about their operations and how we can make them more efficient, help them manage inventory, and keep their employees safer. Developing the right system configuration for our own company and then using it every day really drives home how essential BinMaster solutions can be to all of our customers.

Scott Hudson, EVP of Sales, BinMaster

A SmartBob cable-based level sensor performs as an automated tape measure. An extended vibrating rod is used for high level control to alert delivery drivers when the silo is full.

This information has been sourced, reviewed and adapted from materials provided by BinMaster.

For more information on this source, please visit BinMaster.