Radio Frequency (RF) • Dielectric • Heating Systems • Sealing • Welding

RF Systems - Mainstay for Automotive & Other Industries

Radio Frequency (RF) or Dielectric heating is a process that has been the efficient and cost-effective backbone of many industries where heat is needed for sealing, welding, drying, curing, or baking of various manufactured products.

• PLASTICS - Heat Sealing/Welding, Forming, Preheating
• WOOD - Drying, Moisture Leveling, Gluing, Curved Plywood
• COMPOSITE MATERIAL - Heating, Curing, Bonding
• PRINTING/BINDING - Drying Ink, Curing Glue
• FOUNDRIES - Baking Cores, Lost Foam Drying
• PAPER - Drying Coatings, Moisture Leveling
• TEXTILES - Drying, Bonding Interfacing
• RUBBER - Preheating, Vulcanizing
• CERAMICS - Drying, Sintering

RF preheaters are used to heat resin and composite materials with a suspended electrode prior to molding. Some automotive components formerly made of steel are now made of composites. Once the composite material is preheated, formed in a mold and cooled, it will never warp or disfigure, regardless of the heat applied to it. Preheaters range in size from 4 kW up to 20 kW and employ either a removable tray or a conveyor belt for the material.

Stray-field RF applicators were developed for heating thin materials such as strands, fabrics or webs. Material is carried on a thin conveyor belt into a system employing parallel rods or structural members between which the high voltage RF field is developed. The material can be passed over, under, or between the electrodes.

Stray-field drying is excellent for paper and webs. If a coating is involved, RF is usually employed in the initial stage. It sets up the coating so that subsequent cylinder dryers and hot air can be used without damaging the surface. Adding RF to the drying chain increases line speed because the resultant rapid drying enables more efficient performance from the following cylinders.

In the Automotive Industry

RF is used to bond pads to carpet, and seal door panels, visors, headliners, and numerous other automotive components, as well as to weld convertible tops to glass. Additionally, RF bonders are utilized to cure thermoset adhesives to assemble composite exterior panels such as hoods, doors, fenders and lamp assemblies.

As part of our exclusive AUTOTRIM™ line, we engineered, built and installed the largest and most sophisticated RF automotive system ever manufactured. It is used to make parts for Saturn cars. We also created two of the largest fixed frequency AUTOTRIM™ systems ever built for manufacture of other GM car parts. Nemeth Engineering Associates, Inc. was awarded the prestigious Professional Engineer’s Kentucky Governor’s New Products Award for our rotary AUTOTRIM™ system.

Nemeth Engineering Associates, Inc. engineers designed and custom-manufactured an RF system for sealing hard glass into automobile convertible tops. We built the first automated wide roll joiner for vinyl fabric. Nemeth spearheaded creation of a system for manufacture of three-dimensional seals on leather-like interior door skins. Our engineers and technicians designed and installed the first commercial edge bonding systems for sealing automotive door panel upholstery onto an ABS panel.

In the Medical Equipment Industry

RF bar sealing systems are widely employed for welding various disposable medical products, ranging from IV bags to aircasts. RF is also used for sealing tarpaulins, truck covers, tents, signs and inflatables.

Nemeth Engineering Associates, Inc. has created several complex medical industry systems. These include presses used for mattresses, IV products, bags, examination tables, oncology, respiratory products, urology and blood collection products. Other medical product systems we’ve built are used for medical pads, cushions, covers, and inflatables.

In the Wood Products Industry

Curved plywood, particleboard and panels are cured in RF presses featuring a heated platen. The platens are designed as parallel plates or electrodes. Power can run from 400 kW up to 1,200 kW and more.

RF ovens utilized for baking have a suspended electrode operating against a bedplate. Ovens usually employ a conveyor belt to transport the material through the oven. Certain foods and drugs are dried in RF ovens. A variety of bulk materials such as resin-bonded sand, ceramics and insulation are also dried in RF ovens.

Nemeth Engineering Associates, Inc. has manufactured large architectural curved plywood systems to save glue-drying time in huge required molds. We also led the way in several other RF wood drying, pressing and gluing systems.

In the Government Labs

In 1990, an agent acting on behalf of the United States Army Corps of Engineers chose Nemeth Engineering Associates, Inc. to engineer and manufacture suit sealing systems used in its Chemical and Biological decontamination program. Due to the highly critical nature of application, equipment had to be built to minute and exacting specifications. Nemeth delivered and the program continues today.

In the Textile, Rubber & Plastics, Ceramics, Foundry & Printing/Binding Industries

RF is also utilized for drying and bonding interfacing in the textile industry, preheating and vulcanizing rubber, drying and sintering ceramics, baking cores and lost foam drying in foundry applications and for ink drying and glue curing in the printing and binding industries.