Scaling Up

The recycling industry revolves around weight, as both the buying and selling of recycled materials are based upon the weight of the collected items. Whether the goal is to optimize profits or to pay for precisely the materials purchased, scale equipment capable of reliable and repeatable weighing is essential for improving billing accuracy and the overall bottom line in recycling applications.

With many scale systems available, selecting the proper equipment for a recycling operation is an important task. The selection process involves examining the types of material to be recycled, including the average weight of each load, as well as the value of the commodity.

The four scale systems typically used for recycling applications are rail scales, truck scales, floor scales and forklift scales. All provide a viable weighing solution, but each differs in load capacity and increment size—making some more well suited for certain application requirements than others. Generally, the smaller or more valuable the load, the more precise the weight measurements must be to attain the proper balance of efficiency and effectiveness.

RAIL SCALES
For the heaviest commodities, a rail scale can deliver an ideal weighing solution for loads weighing 400,000 pounds and greater. These high-capacity scales can be modular decks that are spaced to match up below the axles of the cars to be weighed, or sections of instrumented rail that can be installed right on the existing ties and ballast.

Rail scales can be configured for static or in-motion weighing. Many systems employ the use of RFID (radio frequency identification) tags and readers for more complete tracking of the data.
Besides total car weights, rail scales also can be set up to provide readings for individual trucks, axles and even wheels. For approved, legal weighing at capacities greater than 200,000 pounds, a rail scale must be set at 50-pound increments.

The scale is connected to a digital instrument that will record transactions and display the weight. A variety of peripheral devices, such as a printer, PC or remote display, can be connected to the instrument.

Rail scales can be used for recovered fiber, such as leftover rolls from media printing companies, which quickly accumulate in weight and are difficult to lift and ship by truck. Instead, a rail car may be used to collect and transport a large amount of material at once. After it is loaded, the car is weighed on the rail scale, which confirms the weight of the recycled paper. This also prevents the under- or overloading of the rail car, thus ensuring the safe use of each car.

Scrap metal recycling also is an ideal fit for a rail scale. These materials are often bulky and difficult to bundle or sort, so a collection and weighing system requiring no further packaging is often desirable. A rail scale can prevent overloaded cars from leaving the recycling yard, resulting in savings of costly overload fines and preventing shipment delays as overloaded cars are separated and parked until an appropriate amount of material is removed.

TRUCK SCALES
Perhaps the most versatile solution for recycling applications, truck scales can be used to weigh virtually any commonly recycled material. As commodities such as newspaper (ONP), cardboard (OCC), bottles and various metals are often refined and baled for consistency before shipping, these packages can be transported easily via truck. A truck scale then weighs vehicles as they arrive at or depart from the recycling center, allowing facility managers to carefully monitor each transaction.

Truck scale systems consist of a rugged platform and a digital instrument to record transactions and to display the weight. For stand-alone weighing applications or situations where a level of automation is desired, this indicator can be incorporated into a control system adjacent to the platform that requires no scale operator on duty. A driver simply stops on the scale and provides an identification number as well as any other necessary data about the transaction. The vehicle then exits the scale to be loaded or unloaded. Afterward, the vehicle returns to the scale so that an outgoing weighment may be acquired, and the controller prints a ticket displaying the weight and driver/truckload data, with all collected information stored in the controller’s database or, in some cases, wirelessly transmitted to recycling center computers—a significant advantage in remote applications.

With a maximum legally approved increment size of 20 pounds, truck scales provide accuracy suitable for loads weighing tens of thousands of pounds. Many scales can handle up to 270,000 pounds, tackling a broad range of commodities while facilitating efficient, unobtrusive weighing.

FLOOR SCALES
For commodities with a higher per-pound value, such as electronic equipment and fine metals, floor scales are designed to deliver high-accuracy weighing in a low-profile, convenient-to-access design. These scales boast a mere 1-pound graduation—an important feature in applications where even small variations or inconsistencies can make a huge difference to the bottom line.

Floor scales are usually centrally located at a recycling center, so forklift drivers and other personnel can access the scale as conveniently as possible when traveling from all areas of the building. A forklift driver stops on the scale or sets a pallet/container on the scale so that the load weight can be derived. The scale system may include a simple indicator that allows the operator to record and electronically print the captured weight information. This data collection and documentation process also may be automated through the use of a more sophisticated weight indicator—such as one that incorporates bar-code scanners to record the product ID for each load and a WiFi interface to communicate weighments to a PC data collection system. Many floor scales come equipped with ramps—often one on each side—to help facilitate motorized vehicle access and accommodate various traffic patterns. While forklift drivers may need to adjust their routes and/or wait their turn to access the scale, when profits from materials this valuable are at stake, many recyclers agree that it’s worth the wait.

Floor scales combine flexibility—with a wide range of platform sizes and capacities up to 50,000 pounds—with workplace safety. A non-slip scale surface and sturdy feet, combined with low-profile or pit-mounted options, are designed to ensure that the loading, weighing and unloading processes are as risk-free as possible. A durable powder-coat finish on the scale surface ensures it withstands frequent use in busy recycling center environments. In addition, stainless steel floor scales are available that offer superior corrosion resistance for the harshest environments.

FORKLIFT SCALES
To seamlessly integrate weighing and data management into recycling centers, forklift scales allow users to weigh bundled and palletized recycled materials en route. This advantage expedites operations by allowing forklift drivers to take commodities directly to storage upon delivery, tracking the weight, origin and storage location during transport. The data can then be transmitted wirelessly from the warehouse to management’s computers for simple reference, facilitating instantaneous, accurate weight data acquisition and improving billing and inventory management.

During installation, a scale unit is bolted onto a forklift carriage, allowing drivers to lift, weigh, move and record the weight of a load all at once. This design makes the scale a suitable solution for new and retrofit applications, as the installation causes no damage to forklifts and allows the scale to be simply removed and reinstalled onto another forklift as needed.

A forklift scale carriage using electronic weight sensors—with no springs, flexures or hydraulics—is designed to deliver dependable weighing, even if the forklift mast is tilted or the pallet load is off center. These sensors may be configured to compensate for inconsistent weighing conditions, such as when the forklift is on uneven ground, to provide reliable, repeatable weighing. Then, the driver uses an in-cab instrument to manage data collection and communicate weight data to recycling center computers for simple reference.

Forklift scales are ideal for smaller loads—some provide legal-for-trade weighing of loads up to 5,000 pounds. With a 5-pound graduation, forklift scales are more well suited for items such as plastic and glass, rather than expensive precious metals that may be billed by the gram. For the right type of commodity, the time savings offered by forklift scales can result in a fast return on investment.

Examining both the type and amount of materials to be recycled, as well as the shipping method to be used and scale accuracy required, plays an important role in the selection of a weighing solution for a recycling center. While these factors vary, the most important factor does not: In each case, accurate and efficient weighing of recyclables is crucial for optimizing profits and improving overall operations.