Vibratory feeding and conveying equipment has been used in the manufacturing industry for several decades to move fine and coarse materials into mixers, furnaces, production processes or final containers.
Additionally, these machines are used to advance materials such as glass, foundry, steel and plastics through manufacturing facilities as well as recycling materials, pulp and paper, dry bulk solid materials and others. This flexibility in design, process and utility makes vibratory feeders a great option for most production systems.
The information in this article will assist plant managers and equipment operators in selecting the proper feeder to effectively handle various materials, particularly in manufacturing settings where hazardous dust is present.
Feeders Withstand Harsh Environments
In a manufacturing plant, vibratory feeders meter product from hoppers and deposit them onto conveyors, elevators, calciners, screeners or other processing equipment. Vibratory equipment is also utilized for many types of screening—including size separating, scalping or removing oversized product and conglomerates—as well as de-dusting or removing fines.
Vibratory feeders and conveyors have been upgraded and modified over the years to meet the demands of manufacturing applications. The latest equipment offers increased energy savings, more precise control over material flow, easier maintenance and a broader variety of options.
Vibratory equipment, regardless of its type or size, is built to withstand the harsh environment of the manufacturing industry. For example, vibratory feeder trays from Eriez are manufactured from 316L stainless steel which is far less susceptible to corrosive materials. Dust-tight construction and a splash-proof design make internal drive components more suitable for dusty or wet environments. Some feeders are built with galvanized, nickel-plated or Teflon-coated drives.
Choosing the Right Feeder
Dealing with hazardous dust in many manufacturing operations is an ongoing safety issue. Electromagnetic vibratory feeders from Eriez are available with electromagnetic drives that can be used in a Class II hazardous dust environment in groups F and G, as defined by the National Fire Protection Association. Eriez also has specially built drives that can operate in temperatures up to 300 degrees F.
Materials which are dry, free-flowing, pelletized or granulated are typically conveyed using an Eriez model A or C high frequency electromagnetic feeder. These units, which are mainly used for regulating granular flow from a hopper to a second process before final packaging, control material flow from a few pounds to several tons per hour. They are custom designed to accommodate material flow from a few feet with a single drive and up to 20 feet with multiple drives.
Another type of feeder is the High-Speed (HS) unit, which is ideal for rapid on/off cycling and features a faster speed rate. This feeder is an excellent choice for use with weigh scale and packaging machines. Like other feeders in the Eriez line, HS units install easily in tight spaces.
Eriez’ newer model electromagnetic feeders—called High Deflection (HD) feeders—effectively convey fine powders. These low-frequency HD feeders feature increased feed rates and handle a broad range of materials.
Materials from -50 mesh to -400 mesh tend to fluidize and flush on traditional electromagnetic feeders. After significant research and development efforts, Eriez HD Feeders now offer high deflection of up to 3/16-inch (4.8 mm) and lower frequency (30 cycles per minute) to handle finer products.
Electromechanical feeders are also well suited for the manufacturing industry. These low-profile units are mainly used for metering product below hoppers or transferring product from one conveyor to another. They are equally as rugged as their electromagnetic counterparts, but operate at a lower horsepower to enable greater energy savings.
Mechanical drives create a vibratory motion of a tray. This motion is caused by either a direct mechanical linkage (pushrod) or by a stimulating motion with out-of-balance weights and then amplifying that vibration into the tray through a set of springs.
Tray Designs are Limitless
The shape, length and width of modern feeder trays are practically limitless. Customers can order custom feeder trays to satisfy their unique process requirements. Every configuration of flat, curved, v-channel and tubular designs are available.
Trays are typically fabricated from mild steel for general purpose processing or stainless steel for heavy duty manufacturing applications. Some trays are constructed of corrosion-resistant alloys such as titanium or Hastelloy. Tray lining options include abrasion resistant steel, stainless steel, urethane, rubber and other coatings.
Trays that include features such as a tray cover or screen deck incorporate quick-release fasteners that enable these components to be removed without tools. Once the fasteners are loosened, the component simply lifts and disconnects from the tray for easier cleaning.
Spring Systems from Steel to Fiberglass to Carbon Fiber
Springs are an integral part of the feeding system process because they transmit the vibration from the drive into the tray, causing the material in the tray to move. Like trays, springs now come in a variety of materials, sizes and configurations to meet application requirements.
Small electromagnetic feeders, light to medium duty conveyors and most high precision vibratory equipment use fiberglass or carbon fiber as their primary spring action material.
Other types of spring materials are incorporated based on the application. Steel springs are commonly used on heavy-duty and high temperature applications. These springs are effective in ambient temperatures up to 300 F.
Dense rubber springs are utilized on heavy-duty feeders and conveyors to provide stability and motion control between the drive and tray. However, rubber springs are limited to use in environments below 120 F.
Technical Support is Key
Purchasing and installing a vibratory feeder poses fewer risks today because of the availability of technical assistance before and after the sale. Before a purchase is made, material samples can be tested at the Eriez Technical Center to determine the optimum piece of vibratory equipment.
The staff at the Technical Center perform tests on representative material samples to determine the proper model and size of feeder/conveyor for any given operation. The company maintains a library of historical data from prior tests which can be used for comparative analyses to help customers with product selection. This proven approach of pre-testing helps eliminate the potential error of installing an undersized or oversized piece of equipment for the job at hand.
Customers can visit the facility, located near Eriez’ World Headquarters in Erie, Pennsylvania, to witness tests firsthand. Alternatively, they can choose to view the testing online in real-time or request a video of their product test.
About the author: Linda Mioduszewski is Senior Technical Sales Representative for Eriez. She can be reached at firstname.lastname@example.org or by calling Eriez at 814-835-6000. Visit Eriez at www.eriez.com for product information.