Weight is a key factor in the recycling industry: the buying and selling of recycled materials are based upon the weight of collected items. To optimize profits or, in some cases, to only pay for precisely materials purchased, scale equipment capable of repeatable and dependable weighing is crucial for improving billing accuracy and the overall bottom line.
As a plethora of scale systems are available, selecting the proper equipment for a recycling operation is an important task. The selection process involves examining the type of materials 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 better suited for certain application requirements than others. Generally, the smaller or more valuable the load, the more precise the weight measurements must be in order to attain the proper balance of efficiency and effectiveness.
To accurately weigh the heaviest of commodities, a rail scale delivers an ideal solution for loads of 400,000 lbs and beyond. These high-capacity scales can be modular decks 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 use RFID tags and readers for more complete data tracking. Besides total car weights, rail scales can also be set up to provide readings for individual trucks, axles and even wheels.
For approved, legal weighing at capacities above 200,000 pounds, the rail scale must be set for a 50-pound increment size. The scale is connected to a digital instrument that records transactions and displays the weight. Many peripheral devices can be connected to the instrument such as a printer, PC or remote display.
Rail scales can be used for recycled paper 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 materials at once. After it’s 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 utilization of each car.
Scrap metal recycling is also 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 is savings of very costly overload fines and shipment delays (as overloaded cars are separated and parked until an appropriate amount of material is removed).
Truck scales can be used to weigh virtually any commonly recycled material, making them perhaps the most versatile solution for recycling applications. As commodities such as newspaper, cardboard, bottles and various metals are often refined and baled for consistency before shipping, these packages can be easily transported via truck. A truck scale then weighs vehicles as they arrive at or depart the recycling center, allowing site managers to carefully monitor each transaction.
Truck scale systems consist of both a rugged platform and a digital instrument to record transactions and display the weight. For standalone 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 weight can be acquired; 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 increment size of 20 pounds to be legal and approved, truck scales provide accuracy suitable for loads weighing tens of thousands of pounds. Many scales handle up to 270,000 lbs., tackling a broad range of commodities while facilitating efficient, unobtrusive weighing.
For electronic equipment, fine metals and any commodities that deliver a higher per-pound value, a floor scale provides high-accuracy weighing. Scales should boast a mere one-pound graduation — an important feature in applications where even small variations or inconsistencies can make a difference to the bottom line.
Floor scales are usually located centrally at a recycling center, so forklift drivers and other personnel can access the scale conveniently when traveling from all areas of the building. A forklift driver stops on the scale or sets a pallet/container on it so 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 may also 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 weights 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. Forklift drivers may need to adjust their routes and/or wait their turn to access the scale, but when profits from materials this valuable are at stake, many recyclers agree it’s worth the wait.
Scales should combine flexibility — with a range of platform sizes and capacities up to 50,000 lbs. — with workplace safety. A non-slip scale surface and sturdy feet, combined with the low-profile or pit-mounted options, ensure that the loading, weighing and unloading processes are as risk-free as possible. A durable powder coat finish on the scale surface will ensure it withstands frequent use in busy recycling center environments. In addition, stainless steel floor scales offer superior corrosion resistance for harsh environments.
Forklift scales integrate weighing and data management into recycling operations, allowing 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 both 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 is needed.
A forklift scale carriage utilizing electronic weight sensors — with no springs, flexures or hydraulics — delivers 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, su
ch as if 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 lbs. With a 5 lb. graduation, forklift scales are better suited for items such as plastic and glass, rather than expensive electronics that may be billed by the gram. For the right type of commodity, the time savings afforded by forklift scales result in a fast return on investment.
Don Halbert is Global Product Manager, Forklift Scales and Larry Behrens is Global Product Manager, Truck and Rail Scale, for Avery Weigh-Tronix in Fairmont, Minnesota. Canadian customers can visit the company’s website at www.averyweigh-tronix.ca