Marking Machinery

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Most businesses in the automotive, medical and aerospace industries refuse to even consider purchasing inadequately marked products from suppliers as the necessity for accurate product identification grows. Many common everyday products such as credit and debit cards, packaging and storage boxes, electronic and consumer parts etc. are marked by marking machine manufacturers. While metal marking remains a common marking process, marking machinery is able to mark other materials, such as paper, plastic, wood, leather, glass, fabric and textiles. Jewelry, writing utensils, greeting cards, wood trim, cables and wiring and glass sculptures represent the wide range of materials on which marking systems are used. Marking machinery can also produce marks for tracking parts within the whole manufacturing process, making the marks an invaluable element in quality assurance. Marking systems are made up of the machines used to emboss, etch, stamp or print designs on many different surfaces. They employ many techniques and marking tools including: laser markers, press markers, roll markers, dot peen machines, stylus markers, and nameplate markers. Other marking tools include presses such as stylus marking devices, engraving machines, roll or rotary marking devices, hot stamping machines, numbering machines, embossing machines and etching machines. These machines often employ specialized marking tools like steel stamps and scribers. Printing machines, like industrial inkjet printers are also used for marking the surface of flat products.

A variety of techniques are used in the process of part marking to create designs on products, the most popular of which are laser marking, plasma etching and hot stamping. Laser marking is an environmentally friendly process that utilizes a high energy beam of laser radiation to directly mark the surface of materials. The types of laser marking are classified according to the length of the beam and this length is determined by the properties of the material being marked and how well the material responds to laser energy. Plasma etching is divided into two categories: vacuum type, the most common process, and normal-pressure type. In the vacuum type, plasma is generated from gases, such as oxygen, under vacuum pressure to activate the molding surfaces. This type is the most effective for the purpose of surface modification but is inferior in workability, since it must be a batch process and can cause deterioration of the moldings if the processing time is too long. There are also two different methods of hot stamping. In using a stamp press, a metallic stamp or die is heated with a hot plate and presses a stamping foil onto the surface of the part to be marked. Hot stamping with a rubber press is very similar to that in which a stamp press is used, except that a heat-resistant rubber or silicone plate is used instead.

Some marking machines use other methods to apply marks to products. Embossing machines mark ductile material like plastic and leather with a 3 dimensional image using heat and pressure. This imprints product information on the surface of the material causing permanent deformation. Credit cards are marked with this process, resulting in upraised numbers and letters. Engraving machines are similar, but they are able to cut grooves into much harder surfaces like metals. Jewelry is processed with engraving machines. Another type of marking device is a numbering machine which is used to print consecutive numbers on papers, mostly for legal documentation purposes. Marks on papers are often printed on industrial inkjet printers, a larger version of printers used at home and in the office. For 2 dimensional marks that need to be printed on 3 dimensional products, pad printing machines are used. These printers use silicone pads to transfer images from a printing plate to a product's surface. They are used to mark products like electronics, toys and medical equipment. For low volumes, steel stamps are used to mark products by hitting or pressing a marked stamp into material causing an indentation. These include hand stamps and stamp marking kits, which are done by hand, and press stamps, which are components in a stamping machine typically powered by hydraulic or pneumatic power. Scribers are components of any machine that ingrains a mark on material. They are thinly shaped and can be made of metal, diamond or lasers.

Marking machine manufacturers produce a variety of machines and models. The proper selection of a marking machinery system depends on a variety of factors, including industrial application, product material and product volume. For each marking machinery choice there are positive points and drawbacks. Hand stamping is cheap and easy to implement as it does not require expensive machinery or highly skilled operators, but it is labor intensive and inconsistent. If mark placement and alignment are important factors, or if the marking if for a large volume of products, it might be worth investing in a marking machine system. Chemical etching is also inexpensive, but it too provides inconsistent results so it would only be advisable to use it on a less precise product or material. Inkjet printers are much faster but are an impermanent and environmentally hazardous solution. Presses can make fast, permanent marks, but they are not very flexible and are time consuming to set up. They also cannot be used on hard or fragile parts and can be dangerous to operate. Before determining which marking machine is appropriate for an application, consider the cost of spare parts of the marking machinery, the difficulty of maintenance, the size of the marking system and the degree of difficulty of integrating the system with other production systems already in place.

Marking Machinery and Marking Machine Manufacturers Image Provided by Schmidt Marking Systems

Marking Machinery Types

• Bar code marking machines use a CO₂ laser system to mark metal tools and parts with barcodes and serial numbers. The markings are permanent and impervious to scratching, lubricants, salt water spray and abrasion.
  
• Code dating machinery marks a product with a code to convey information such as the product packaging date and expiration date.
  
• Computer-controlled Braille embossers imprint patterns on paper or thin card to produce tactile Braille symbols. The products manufactured by computer controlled Braille embossers vary according to whether they have been developed for home use or production.
• Dot peen machines enable the process of dot peening, which is a marking technique of imprinting identifying marks into the surface of a material through the use of a multiple-axis marker-stylus.
• Embossing machines use a metal die to leave a 3D implant on a surface.
• Engraving equipment cuts into a product to produce a wide variety of characters that can then be colored. Engraving is a common metal marking technique often used to mark round objects, such as jewelry, cables and wires.
• Etching machines use chemicals and acids to engrave metal surfaces.
• Hot stamping machinery consists of a press containing a heated printing head and an engraved die, which can produce holograms, credit card characters and many different package designs. The press pushes hot stamping foil on to flat paper, plastic, wood, leather, or certain fabrics, leaving the design imprinted on the material in the color of the foil.
  
• Industrial inkjet printers reproduce high quality digital imagery by using spray nozzles to place variable sized drops of ink onto paper and other materials.
• Laser marking systems mark objects through laser radiation. No contact occurs between the laser marking system and the product, making this process advantageous in marking sensitive products, such as glass.
  
• Marking systems include a wide variety of machines used to emboss, engrave, etch, stamp, or otherwise create designs on many surfaces.
• Marking tools create images, designs and impressions on materials ranging from metal and glass to plastic and stone.
• Numbering machinery works manually or automatically to mark products, such as license plates, tags and keys, with bar codes and other numbers.
• Pad printing machines use ink pads to allow the transfer of 2-dimensional images to 3-dimensional objects.
• Roll marking machines consist of cylindrical roller dies with engraved impressions of the required design, which produce indentations and graduations on an object. Roll marking is used on products with flat or round surfaces.
• Scribers are hand or machine operated tools used to etch or engrave permanent lines and markings in industrial products. 
• Steel stamps have raised images on one or more surfaces which are then pressed against the face of a target object in order to leave a corresponding indented pattern in that material.

Marking Machinery Terms

Bar Code - A code used in the identification of products through electronic scanning, consisting of a sequence of parallel lines that vary in width. The spacing between the individual bar lines also varies.
 
Bevel - The slant from the surface of an engraved character to the background is referred to as the first, or character, bevel. The second bevel is the clearance taper, or sighting angle, which is usually a 45-degree angle on each side of the hand stamp.
 
Bottoming - Impressing a stamp or die to the background of the characters or design. Bottoming also refers to the ironing out of metal displaced by a stamping die.
 
Character - In marking systems, the individual letter or number marked upon an object. Character faces and styles vary.
 
Chase - A frame of metal in a hot stamping press that holds the die in place during the stamping process.
 
Chemical Etching - A process in which a mark is burned onto a product through the application of a screen and an acid.
 
Die - In marking machines, a metal plate onto which a design or image is etched or engraved to be stamped, rolled or printed onto a product.
 
Dot Marking - Also called "dot peening," it is a type of micro-percussion marking system in which sequences of dots are used to mark an object according to design requirements.
 
Etching - A process in which a metal plate is coated with wax through which lines are cut. A corrosive acid is applied, which removes the metal under the lines.
 
Foil - In hot stamping, a thin, flexible material consisting of a coat of color that transfers to the stamped product during the stamping process.
 
Hand Stamp - A steel stamp that engraves a design onto an object by striking the stamp with a hammer. Hand stamps are useful when producing low volumes of products.  
 
Impregnation Printing - The process of transferring a special ink based on a sublimating dye to the inside of molded parts. Impregnation printing is useful in applications requiring wear resistance.
 
Ink Jet Marking - Marking system in which a mist of ink is transferred to an object to mark the object according to design requirements.
 
Insert - A stamp or type placed with a piece of marking equipment, such as a die, to produce a particular design or image.
 
Intaglio - An image or design created by engraving the design onto a metal plate and filling the recessed design with ink. A damp piece of paper is then pressed against the plate in a roller press, producing a reverse image on the paper.
 
Mortise - A depression or cavity in a die into which an insert is placed.
 
Numbering Head - A device that marks products with multiple characters simultaneously for fast and consistent identification.
 
Pad Printing - The process of transferring ink to a molded part by filling ink in a plate in which characters are engraved hollow, moving it to a pad and pressing the pad on the face of the molded part; the ink is then cured by thermal treatment, ultraviolet treatment or other curing processes.
 
Steel Branding Die - A die that can be heated to a temperature sufficient for burning characters or designs into wood, leather and other materials.
 
Steel Stamp - A marking device that is pressed or hit into a material. Steel stamps include hand stamps, press stamps and stamp marking kits.
 
UPC (Universal Product Code) Number - A number code below the bar code that consists of 14 numbers, which provide product identification.
 
VIN (Vehicle Identification Number) - A unique combination of letters and numbers created by a vehicle manufacturer to accurately identify a vehicle.