Rejecting and Depositing Conveyor Systems
Why Is Rejecting Necessary?
Rejecting is a necessary step in any production line to help increase the quality of a business’ output. Not all products are fit to be sold in a marketplace, with some estimates putting 2 percent of output as rejected parts.
Products may be rejected by sight for reasons such as an irregularity or deformity. They may be rejected because of improper weight or missing caps, flaps or labels as well as because of incorrect or unreadable barcodes. Products may also fail a safety test such as by metal detection or X-ray.
Products falling short of specifications must be removed from production lines to prevent failed product from reaching suppliers or the marketplace. Rejecting conveyors are ideal to use in these cases, enabling rejected products to drop onto other conveyors or into bins, also called reject conveyor accumulators, to be taken away. Diverters, pushers and gates may also be used to manipulate product routes.
What Are the Most Popular Conveyor Reject Mechanisms?
The most popular conveyor reject mechanisms are air blast, pneumatic pusher, overhead sweep, pneumatic retract, pivot down/up and linear actuating.
Custom Rejecting Conveyor
Custom reject conveyors make it possible to maximize application performance. Each product’s individual characteristics and weights impact the type of retract, the distance and move required to reject, and the speed of the move.
Product routing is the key to overall throughput of any manufacturing and assembly process. The faster and more consistent product is delivered through the process, the higher the quality and throughput.
Product routing also provides the flexibility to route product through different processes such as individual pack to a bulk fill line.
Rejecting tail is a common type of conveyor reject mechanism. It requires a signal that activates when the tail retracts.
Safely and Efficiently Remove Product With Dorner’s Reject Systems
Dorner offers a variety of ways to reject product. Reject conveyors can be low-tech solutions that just stop the line until an employee can remove the offending product or be high-tech solutions that are as efficient as retracting conveyors. In this latter case, metal detectors, for example, can pick up contaminants in product, and a retract reject conveyor’s tail can automatically retract, dropping the questionable product into a reject bin, sometimes referred to as a reject conveyor accumulator.
Our manual divert arm, featuring FDA-approved belting and plastic components, can quickly and effectively guide product along the line and with a powered transfer module.
Automated reject conveyors also are valued in tight spaces in which employees cannot easily fit as well as in cases in which employees cannot be utilized to check the line every time alarms sound over reject product.
Dorner built a reject conveyor for a customer needing to move different-sized cartons through a pair of inkjet printers. The carton had to be justified and then transferred 90 degrees. The Dorner team built this business a six-conveyor system, including three 3200 Series Conveyors equipped with Intralox’s patented Activated Roller Belt (ARB) technology. The result is, cartons that have not been taped properly are moved down a curved skate wheel conveyor using the retract reject conveyor.
In another case, Dorner constructed a cleanroom conveyor system that utilizes a reject conveyor to drop rejected parts into a custom-designed chute. An additional quality inspection checks parts, with a pneumatic divert gate pushing rejected parts down another chute. We supplied this business with 2200 Series industrial flat belt conveyors to meet its needs.
Depositing Conveyor Systems
Product sometimes needs to be placed onto another conveyor or a tray in precise rows or columns. A retract conveyor serving as a depositing conveyor can be equipped with sensors to ensure the product is placed exactly where it needs to be, whether in a box or on another conveyor.
Depositing is critical in product routing, increasing throughput and improving repeatable accuracy. By precisely locating product on a tray, conveyor or pallet, other processes can be sped up. The movement and time the next process requires is decreased because product is where it needs to be.
Dorner’s high-speed retracting tail conveyors may be used for applications such as depositing, rejecting, stacking and product routing. Sensors trigger when the retracting tails should retract.
Dorner can manufacture custom depositing systems based on our customers’ product and applications as part of our custom conveyor systems service. In one example, the Dorner team constructed a high-speed retractable conveyor for a business that needed to stack sheets of thin extruded food product. Once product reaches the end of the conveyor, a sensor triggers the tail to retract 3 feet in only 0.6 seconds. This retraction enables product to fall on a cart under the retracting tail.
In addition to sensors, push-buttons and manual retraction may be utilized, depending on our customers’ needs. Retracts can have multiple drop zones and can occur infrequently, as needed or reoccur every few seconds with precision.
Industries That Use Depositing Conveyors
All industries utilize depositing conveyors and rejecting conveyors. Quite simply, packaging is utilized across all industries.
Let’s explore a couple of key industries in which depositing conveyors are widely used.
Food & Sanitary
Depositing conveyors are used heavily by the food handling and sanitary industries. Dorner’s food handling and processing conveyors are designed to handle applications from meats and poultry and dairy and cheese to baking and confectionary along with ready-to-eat foods.
Our hygienic designed conveyors meet FDA, BISSC and USDA industry regulations. You can be assured that Dorner’s team can create custom engineered conveyor solutions that meet the needs of your facility.
Our world-class food and sanitary depositing conveyors are designed to operate at fast speeds. These conveyors have achieved an outstanding track record in helping all kinds of food and sanitary businesses maximize their efficiency and productivity levels.
Dorner’s food and sanitary conveyors:
- Are designed for fast and effective sanitation
- Feature custom-designed solutions for unique systems
- Contain three sanitary levels configured to your application
- Clean up two times faster than competing products
- Require less to clean because of Dorner’s hygienic design
- Are built based on Dorner’s commitment to food safety
In one example of a depositing conveyor for food and sanitary use, Dorner helped a customer increase its food production line’s efficiency level. Product had been moving along a conveyor and had to be placed directly onto trays before it was moved into an oven for baking. This business called for a pair of employees to lift product off the conveyor and placing it onto trays. Two additional employees were responsible for bringing over empty trays and filling them with product.
Dorner’s retractable tail solution greatly expedited this entire process. Our solution placed product directly onto the trays. Dorner’s AquaPruf 7400 series conveyor, equipped with three sensors and can be easily disassembled for cleaning in just minutes, detected product on the conveyor belt. Moreover, an AquaPruf 7600 series conveyor, also designed for easy and fast sanitation, is used to convey the baking trays, with sensors used to identify the conveyor belt’s cleat.
Dorner’s depositing conveyors are also relied on by the manufacturing industry such as with material handling and industrial uses and with packaging uses. Businesses manufacturing a wide range of products depend on depositing conveyors to help ensure only product meeting specifications are used in product assembly or shipped to the marketplace.
Most businesses require truly customized depositing conveyor solutions as opposed to a one-size-fits-all approach. It’s important to understand that most competitors’ products are standard-built and cannot be customized to suit your business’ unique needs.
With Dorner, however, our team is able to craft custom depositing conveyors for manufacturing companies that meet our customers’ vision with the goal of maximizing their workflow.