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Stamping

Metal Stamping

We specialize in various OEM metal stamping-welding products with various surface treatments . T

Stamping is a metalworking process by which sheet metal strips are punched using a press tool which is loaded on a machine press or stamping press to form the sheet into a desired shape. This could be a single stage operation where every stroke of the press produce the desired form on the sheet metal part, or could occur through a series of stages.
The most common stamping operations are:

Piercing:

The process of piercing or forming a hole of desired shape typically, in sheet metal. The sheet metal is placed between a male and female tool members namely, the punch and die. The amount of clearance between a punch and die for piercing is governed by the thickness and strength of the work-piece material being pierced. The punch-die clearance determines the load or pressure experienced at the cutting edge of the tool, commonly known as point pressure. Excessive point pressure can lead to accelerated wear and ultimately even catastropic failure. Material specific piercing guidelines typically available in tool and die maker handbooks. As a general rule of thumb, for thin materials, the clearance should be small and there should be a sliding fit to prevent ragged edges or burrs. For thicker materials, there should be significantly higher clearance. Burr height is typically used as an index to measure tool wear as it is easiest to measure during production.

Fine blanking:

Fine blanking is a fully automated precision metalworking stamping process.

There are a number of advantages to fine blanking over conventional metal stamping, with the most important one being that fine blanking provides completely consistent dimensional control. This means that metal components produced by fine blanking have a machined like edge quality and extremely high accuracy immediately following the stamping process, without additional machining. Additionally all holes, profiles, edges, semi-pierces are carried out in one process.

Bending:Bending is a common manufacturing method to process sheet metal. It is usually done on a bend press (or Press brake), but also swing-bending-machines are used. Typical products that are made like this are electrical enclosures.

Forming:

Coining

progressive stamping: Progressive stamping is a metalworking method that can encompass punching, coining, bending and several other ways of modifying metal raw material, combined with an automatic feeding system.

The feeding system pushes a strip of metal (as it unrolls from a coil) through all of the stations of a progressive stamping die. Each station performs one or more operations until a finished part is made per the requirements on the blueprint. The final station is a cutoff operation, which separates the finished part from the carrying web. The carrying web, along with metal that is punched away in previous operations, is treated as scrap metal.

The progressive stamping die is placed into a reciprocating stamping press. As the stamping press moves up, the progressive stamping die opens. When the stamping press moves down, the progressive stamping die closes. When the stamping press opens, the metal material is able to feed. As the stamping press closes, the progressive stamping die performs work on the raw material. With each stroke of the press, a completed part is removed from the die.

Deep Drawing:

Deep drawing is a compression-tension metal forming process in which a sheet metal blank is radially drawn into a forming die by the mechanical action of a punch[1]. It is thus a shape transformation process with material retention. The flange region (sheet metal in the die shoulder area) experiences a radial drawing stress and a tangential compressive stress due to the material retention property. These compressive stresses (hoop stresses) result in flange wrinkles (wrinkles of the first order). Wrinkles can be prevented by using a blank holder, the function of which is to facilitate controlled material flow into the die radius.

The total drawing load consists of the ideal forming load and an additional component to compensate for friction in the contacting areas of the flange region and bending forces at the die radius. The forming load is transferred from the punch radius through the drawn part wall into the deformation region (sheet metal flange). Due to tensile forces acting in the part wall, wall thinning is prominent and results in an uneven part wall thickness. It can be observed that the part wall thickness is lowest at the point where the part wall loses contact with the punch, i.e. at the punch radius. The thinnest part thickness determines the maximum stress that can be transferred to the deformation zone. Due to material volume constancy, the flange thickens and results in blank holder contact at the outer boundary rather than on the entire surface. The maximum stress that can be safely transferred from the punch to the blank sets a limit on the maximum blank size (initial blank diameter in the case of rotationally symmetrical blanks). An indicator of material formability is the limiting drawing ratio (LDR), defined as the ratio of the maximum blank diameter that can be safely drawn into a cup without flange to the punch diameter. Determination of the LDR for complex components is difficult and hence the part is inspected for critical areas for which an approximation is possible.
Commercial applications of this metal shaping process often involve complex geometries with straight sides and radii. In such a case, the term stamping is used in order to distinguish between the deep drawing (radial tension-tangential compression) and stretch-and-bend (along the straight sides) components.

Deep drawing has been classified into conventional and unconventional deep drawing. The main aim of any unconventional deep drawing process is to extend the formability limits of the process. Some of the unconventional processes include hydromechanical deep drawing, Hydroform process, Aquadraw process, Guerin process, Marform process and the hydraulic deep drawing process to name a few.

Industrial uses of this process include automotive body and structural parts, aircraft components, utensils and white goods. Complex parts are normally formed using progressive dies in a single forming press or by using a press line.

Embossing:

Embossing is the process of creating a three-dimensional image or design in paper and other ductile materials. It is typically accomplished with a combination of heat and pressure on the paper. This is achieved by using a metal die (female) usually made of brass and a counter die (male) that fit together and actually squeeze the fibers of the substrate. This pressure and a combination of heat actually "irons" while raising the level of the image higher than the substrate to make it smooth. In printing this is accomplished on a letterpress. The most common machines are the Kluge Letterpress and the Heidelberg Letterpress. The term "debossing" enables one to distinguish an image lowered into the surface of a material, in distinction to an image raised out of the surface of a material. Both are "embossing" per se. For embossing metal, see repoussé.

The embossing process can be applied to textiles as non-wovens to get better finished products as sanitary napkins, diapers, tissue paper and others. In printing it is used as an accent process and can be used in conjunction with ink called colour register embossing or with no ink called blind embossing. It also can be used with foil stamping which when embossed with foil is known as combination stamping or combo stamping. All of these processes use a die and counter die. Most types of paper and boards can be embossed and there are no restrictions on size.

Embossing involves a separate stage in the production process, after any varnishing and laminating. This process costs as much as printing.

The term embossing also refers to a different technique for creating raised images on paper. In this process, a rubber stamp is used to apply glue to paper in a desired pattern. Embossing powder is dusted over the paper, where it adheres to the glue. The powder is blown away from the unglued areas, then the paper is subjected to heat, which causes the powder to melt and fuse over the glued area. Then the heat is removed, and the liquid hardens into a palpable raised surface in the shape of the stamped pattern.

Extrusion:

Extrusion is a manufacturing process used to create long objects of a fixed cross-sectional profile. A material, often in the form of a billet, is pushed and/or drawn through a die of the desired profile shape. Hollow sections are usually extruded by placing a pin or piercing mandrel inside of the die, and in some cases positive pressure is applied to the internal cavities through the pin. Extrusion may be continuous (producing indefinitely long material) or semi-continuous (producing many short pieces). Some materials are hot drawn while others may be cold drawn.

Extrusion of a round blank through a die
Extrusion of a round blank through a die

The feedstock may be forced through the die by various methods. A single or twin screw auger, powered by an electric motor, or a ram, driven by hydraulic pressure (for steel alloys and titanium alloys for example), oil pressure (for aluminum), or in other specialized processes such as rollers inside a perforated drum for the production of many simultaneous streams of material.

Extrusion simulation tools help to understand the extrusion process and to optimize development of tools and products.

Extrusion is also the first step in the process of extrusion and spheronization, a commonly used process in the pharmaceutical industry.

Commonly extruded materials include metals, polymers, ceramics, and foodstuffs.

Products Mainly Used for:

Industrial machinery parts, construction building fixing parts , furniture hardware accessories , electric equipment spare parts

Products build by metal material:

Galvanized steel, zincalume Aluminum,Stainless steel 302 303 304 316,low Carbon steel,hot rolled,cold rolled steel 1008/1010, Alloy carbon steel,Copper,bronze,silver,silicon steel,

Finish:

Polish, heat treatment, oxygenation,spray powder coating, black coating, zinc coating,brass plated,nickel coating, chrome coating,precision CNC machining,