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Converting companies are companies that specialize in modifying or combining raw materials [1] such as polyesters, adhesives, silicone, adhesive tapes, foams, plastics, felts, rubbers, liners and metals, as well as other materials, to create new products.
Materials such as paper, plastic film, foil and cloth often are produced in long, continuous sheets that are rolled up for more convenient handling and transportation. These rolls of material vary significantly in size and weight —2–203 inches (5–516 cm) wide and weighing as much as several tons. The converting industry takes these continuous rolls of thin, flat materials — known as webs — threads them through processing machines (such as printing presses, laminating, coating and slitting machines) and converts or changes the web of material into an intermediate form or final product. [2] For example, a converter’s equipment might take a web of plastic film, cut it into lengths, and fuse their edges, thus converting it into plastic bags. This activity is known as web processing. [3]
Typical converting processes include coating, laminating and printing. [4] Coating technologies can include hot melt coating, gravure coating, curtain coating and slot-die coating. The most common printing techniques are flexo printing and rotogravure (gravure) printing. Both print processes are suited to high speed roll-to-roll processing.
Many converting companies will process large diameter, wide rolls of material as this increases the converting efficiency by minimising changes. On completion of the converting process the rolls may be cut into smaller rolls on a slitting machine or a sheeter. [5] These rolls or sheets are then a convenient size for handling on packaging and other machines. Further processes such as collation may occur after sheeting.
Depending on the specially of the converter, many other processes might be involved. These might include: shearing, die-cutting, laser cutting, heat sealing, laser converting, perforating, Ultrasonic welding, Surface finishing, etc. [6]
When converting from rolls of material, web alignment is an important part of a converting operation as a moving web of material has a tendency to track off course and wander out of alignment during the converting processes. To avoid these problems, engineers have developed a variety of automatic web-guiding systems that assure production accuracy and reduce waste. Web-guiding systems typically are positioned just before a critical stage on a converting machine (for example, just before a print station on a printing press).
Each type of web guiding system uses a sensor to monitor the web position for lateral tracking, and each has an actuator to shift the running web mechanically back on course whenever the sensor detects movement away from the set path. Actuators may be pneumatic or hydraulic cylinders, or some kind of electromechanical device. Because the web may be fragile — particularly at its edge — non-contact sensors are used. These sensors may be pneumatic, photoelectric, ultrasonic, or infrared. The system’s controls must put the output signals from the sensors in to a form that can drive the actuator. Many controls today are electronic, typically using an amplifier to convert signals from the sensor, then commanding a special servo motor incorporating a lead or ball screw for guiding actuation. The latest web guiding systems have touch screen controls to simplify the setup procedure. Some web guiding systems have been designed specifically for the converting industry.
Many converters specialize in
Some converting companies now incorporate electronics in their finished products. For example, converters producing RFID stock labels must incorporate RFID chips and antenna inlays. [7] The electronic components make up the RFID tag. The tag stores the information about the items that have been tagged. These converters therefore sometimes incorporate volume electronics manufacturing practices including controlling static electricity, electronic manufacturing test and similar processes. Solving some of the issues of inclusion of materials sensitive to external influences has led to more tech companies embracing roll-based manufacturing processes, with particular success in the lithium ion and solar cell manufacturing sectors. [8]
Paper converting can refer to manufacturing processes involving paper as the raw material. This raw material, similar to other converting industries, can be in a roll or sheet form. Paper converting is required for the manufacture of nearly all paper based products, such as magazines, books, newspapers, labels, bags, and general purpose paper products. [9]
The process of processing pre-cut cartons or "blanks" and folding them into the appropriate shape to become finished packaging containers is known as tray forming or carton erecting. This is a specific example of a type of converting. These machines can create, for example, nacho trays, chinese noodle soup boxes, pizza boxes, french fry trays, hamburger clamshells, etc.
Corrugated fiberboard or corrugated cardboard is a type of packaging material consisting of a fluted corrugated sheet and one or two flat linerboards. It is made on "flute lamination machines" or "corrugators" and is used for making corrugated boxes. The corrugated medium sheet and the linerboard(s) are made of kraft containerboard, a paperboard material usually over 0.25 millimetres (0.01 in) thick.
Flexography is a form of printing process which utilizes a flexible relief plate. It is essentially a modern version of letterpress, evolved with high speed rotary functionality, which can be used for printing on almost any type of substrate, including plastic, metallic films, cellophane, and paper. It is widely used for printing on the non-porous substrates required for various types of food packaging.
A paper machine is an industrial machine which is used in the pulp and paper industry to create paper in large quantities at high speed. Modern paper-making machines are based on the principles of the Fourdrinier Machine, which uses a moving woven mesh to create a continuous paper web by filtering out the fibres held in a paper stock and producing a continuously moving wet mat of fibre. This is dried in the machine to produce a strong paper web.
Lamination is the technique/process of manufacturing a material in multiple layers, so that the composite material achieves improved strength, stability, sound insulation, appearance, or other properties from the use of the differing materials, such as plastic. A laminate is a permanently assembled object created using heat, pressure, welding, or adhesives. Various coating machines, machine presses and calendering equipment are used.
Rotogravure is a type of intaglio printing process, which involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a cylinder because, like offset printing and flexography, it uses a rotary printing press.
Thermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mold, and trimmed to create a usable product. The sheet, or "film" when referring to thinner gauges and certain material types, is heated in an oven to a high-enough temperature that permits it to be stretched into or onto a mold and cooled to a finished shape. Its simplified version is vacuum forming.
A calender is a series of hard pressure rollers used to finish or smooth a sheet of material such as paper, textiles, rubber, or plastics. Calender rolls are also used to form some types of plastic films and to apply coatings. Some calender rolls are heated or cooled as needed. Calenders are sometimes misspelled calendars.
Avery Dennison Corporation is a multinational manufacturer and distributor of pressure-sensitive adhesive materials, apparel branding labels and tags, RFID inlays, and specialty medical products. The company is a member of the Fortune 500 and is headquartered in Mentor, Ohio.
Die cutting is the general process of using a die to shear webs of low-strength materials, such as rubber, fibre, foil, cloth, paper, corrugated fibreboard, chipboard, paperboard, plastics, pressure-sensitive adhesive tapes, foam, and sheet metal. In the metalworking and leather industries, the process is known as clicking and the machine may be referred to as a clicking machine. When a dinking die or dinking machine is used, the process is known as dinking. Commonly produced items using this process include gaskets, labels, tokens, corrugated boxes, and envelopes.
Laminated object manufacturing (LOM) is a rapid prototyping system developed by Helisys Inc. In it, layers of adhesive-coated paper, plastic, or metal laminates are successively glued together and cut to shape with a knife or laser cutter. Objects printed with this technique may be additionally modified by machining or drilling after printing. Typical layer resolution for this process is defined by the material feedstock and usually ranges in thickness from one to a few sheets of copy paper.
A web is a long, thin, and flexible material. Common webs include foil, metal, paper, textile, plastic film, and wire. Common processes carried out on webs include coating, plating, and laminating.
Converting was a trade publication and Website owned by Reed Business Information serving the information needs of converters: industries that convert paper, paperboard, plastic film and foil materials into finished, printed packaging such as bags, pouches, labels, tags, folding cartons and corrugated shipping cases.
Roll slitting is a shearing operation that cuts a large roll of material into narrower rolls. There are two types of slitting: log slitting and rewind slitting. In log slitting the roll of material is treated as a whole and one or more slices are taken from it without an unrolling/re-reeling process. In rewind slitting the web is unwound and run through the machine, passing through knives or lasers, before being rewound on one or more shafts to form narrower rolls. The multiple narrower strips of material may be known as mults or pancakes if their diameter is much more than their width. For rewind slitting the machine used is called a slitter rewinder, a slitter or a slitting machine – these names are used interchangeably for the same machines. For particularly narrow and thin products, the pancakes become unstable, and then the rewind may be onto a bobbin-wound reel: the rewind bobbins are much wider than the slit width and the web oscillates across the reel as it is rewound. Apart from the stability benefit it is also then possible to put very long lengths,, onto one bobbin.
A winding machine or winder is a machine for wrapping string, twine, cord, thread, yarn, rope, wire, ribbon, tape, etc. onto a spool, bobbin, reel, etc.
Topflight Corporation is a manufacturer of printed labels and die-cut components. Topflight is ISO 9001:2008 and ISO 13485:2003 certified and is one of the oldest privately owned label companies. Topflight creates products for varying industries: Medical Devices, Pharmaceutical, Consumer & Durable Goods, Cosmetic & Personal Care, Electronics, Tire and Automotive. Based on annual sales of printed and converted labels, Topflight is ranked number 21 on the Top Tag and Label Converters list.
Plastic film is a thin continuous polymeric material. Thicker plastic material is often called a "sheet". These thin plastic membranes are used to separate areas or volumes, to hold items, to act as barriers, or as printable surfaces.
Web-guiding systems are used in the converting industry to position flat materials, known as webs, before processing. They are typically positioned just before a critical stage on a converting machine. Each type of web guiding system uses a sensor to monitor the web position for lateral tracking, and each has an actuator to shift the running web mechanically back on course whenever the sensor detects movement away from the set path. Actuators may be pneumatic or hydraulic cylinders, or some kind of electromechanical device. Because the web may be fragile — particularly at its edge — non-contact sensors are used. These sensors may be pneumatic, photoelectric, ultrasonic, or infrared. The system’s controls must put the output signals from the sensors in to a form that can drive the actuator.
A rotary union is a union that allows for rotation of the united parts. It is thus a device that provides a seal between a stationary supply passage and a rotating part to permit the flow of a fluid into and/or out of the rotating part. Fluids typically used with rotary joints and rotating unions include various heat transfer media and fluid power media such as steam, water, thermal oil, hydraulic fluid, and coolants. A rotary union is sometimes referred to as a rotating union, rotary valve, swivel union,rotorseal, rotary couplings, rotary joint, rotating joints, hydraulic coupling, pneumatic rotary union, through bore rotary union, air rotary union, electrical rotary union, or vacuum rotary union
SDM Strength Film known by the processing names Cross-Laminated Films and Strength Films, is a kind of High Density Polyethylene (HDPE) Cross Laminated Strength Film. Because of proprietary cross-laminated process, SDM Strength Film is very strong and find many application.