Metal Fabrication Processes

Specialized in metal forming processes, ChinaSavvy offers a number of fabrication processes, each meeting ISO 9001:2008 standards.

By applying various tools, our team is able to transform raw materials into assembled products that not only meet the highest quality standards, but your pocket as well.

Metal forming processes within fabrication can be classified as hot, warm or cold, and depends on the temperature at which the material is processed.

A number of factors influence the metal manufacturing processes used to transform metal into a final product. This factors range to include:

• The material being machined.
• The production rate.
• The geometries required.
• And finally the physical requirements of the part.

The standard raw materials used by fabricators include sheet metal, formed and expanded metal (such as tube stock) and castings.

Fabrication can be divided into:

• Metal Forming
• Shearing
• Material Removal
• Other Advanced Methods
• Welding and Assembly

Metal Forming

Bending is used in metal forming processes in order the bend the workpiece to form contours, corrugations, flanges, curls and other desired geometries. This bending is done through the application of force using electrical, hydraulic or pneumatic machines.

Shearing

Used in order to cut straight lines on flat metal stock, conventional shearing involves the an upper and lower blade being forced past each other, the space between the blades being determined by the required offset. In most cases, one of the blades remains stationary.

The materials that are commonly sheared includes stainless steel, aluminum, brass, mild steel and bronze.

CNC Turret Punching is also used in fabrication and involves the creation of shapes in sheet metal. This is achieved by successively punching a series of basic shapes, selected from a rotating turret under CNC control, into the sheet material.

Almost any two-dimensional shape can be produced using turret punching ranging from sheet metal boxes to custom washers and motorcycle parts.

The materials most commonly turret punched includes aluminum, brass, steel and stainless steel.

Material Removal

Various material removal processes are used within fabrication, including:

• Boring
  • Boring entails the production of circular internal profiles in a hollow workpiece or on a hole produced through drilling or other material removal processes.
• Drilling
  • By using a fluted cutting tool, fabrication shops are able to produce holes in a workpiece.
• Grinding
  • A chip removal process, grinding is an abrasive machining process in which the cutting tool is a grinding wheel. A number of different types of grinding methods are used within the fabrication industry today, including:
    • Centerless Grinding – Entailing the use of two wheels - the larger wheel used in order to grind the surface of the workpiece and the smaller wheel used to regulate the axil movement of the workpiece – the types of centerless grinding used includes in-feed or plunge grinding, through-feed grinding and internal centerless grinding.
    • Cylindrical Grinding – This grinding methods is used in order to grind the shoulders and cylindrical surfaces of a workpiece. Also known as center-type grinding, the five types of cylindrical grinding includes outside diameter (OD) grinding, inside diameter (ID) grinding, centerless grinding, plunge grinding and creep-feed grinding.
    • Internal Grinding – This grinding process is used in order to grind the internal diameters of a workpiece. By using internal grinders (capable of swiveling on the horizontal), fabricators are able to grind tapered holes.
    • Surface Grinding – This grinding process entails the use of a rotating abrasive wheel in order to remove material, resulting in the creation of a flat surface.
• Milling
  • CNC Milling allows for the removal of of small chips using a rotating cutter which moves on three axis. Here, the material is removed from the workpiece by performing a number of separate, small cuts. The two major classes of the milling process includes face milling and peripheral milling.
    • Face Milling – This process is used in order to cut flat surfaces (known as faces) into the workpiece or it is used to cur flat-bottomed cavities. Here, the cutting action primarily occurs at the end corners of the milling cutter.
    • Peripheral Milling – In this process, cutting primarily occurs along the circumference of the cutter. This results in the cross section of the surface being milled receiving the shape of the cutter being used. A suited process for cutting deep slots, gear teeth and threads, this process can be seen as the cutter scooping out material from the workpiece.
• Sawing
  • Commonly used in order to cut the the raw material to its approximate size before additional metal forming processes take place, sawing entails the use of a cutting tool in the form of a blade that features a series of teeth. Each tooth on the blade is responsible for removing a small amount material, thus cutting it to the desired (approximate) size.
• Tapping
  • Involving the use of a tool featuring multiple cutting teeth, tapping effectively produces internal threads in a workpiece. Both the drilling and tapping of holes play an important role when it comes to different sections of the metal workpiece (such as the end of the stem, the center of the head and the cross shaft).
• Turning
  • While turning the workpiece on its axis, CNC turning entails the use of cutting tools in order to achieve a desired shape. Here, parts are produced through turning rod material and feeding a cutting tool, which can be fed at a variety of angles, into the material being fabricated. Materials commonly turned includes copper, steel, aluminum, titanium, bronze, brass and stainless steel.

Be sure to read more about precision CNC machining.

Other Advanced Methods

A number of advanced metal forming processes are applied within fabrication. Some of these advanced metal manufacturing processes range to include:

• Laser Cutting
  • Entailing the focusing of a beam of high density energy on the surface of the workpiece, laser cutting involves the controlled evaporation of a portion of the workpiece. Laser cutting is able to deliver a high quality cut and narrow kerf, and can be used to cut aluminum (using a higher power laser), plain steel, stainless steel and spring steel.
• Plasma Cutting
  • Using a plasma torch, this cutting method involves a gas being blown at high speed out of a nozzle. At the same time this gas is blown, an electrical arc is formed, resulting in some of the gas being turned into plasma. The plasma formed is hot enough to melt the metal workpiece being cut and also moves fast enough to blow the metal melted away from the cut.
• Water Jet Cutting
  • Capable of cutting through an aluminum sheet thickness of 120 millimeters, water jet cutting entails the use of a high pressure water jet combined with an abrasive, resulting in a cold cut with sharp edges. This metal manufacturing process can be used on a number of materials ranging to include aluminum, copper, brass, stainless steel and steel.
• Wire Electric Discharge Machining (EDM)
  • Here, a thin, electrically energized wire is used in order to slice through the electrically conductive metal. This method entails the use of rapid, controlled, repetitive spark discharges from the wire to the electrically conductive workpiece. This discharge causes the metal to erode, resulting in a cut.

Note that you can also learn more about various cutting processes by visiting our Aluminum Sheet Fabrication Process page.

Welding and Assembly

Specializing in a number of welding processes, ChinaSavvy’s services n this category range to include:

• TIG Welding
  • Also know as Gas Tungsten Arc Welding (GTAW), TIG welding is arc welding process involving the use of a non-consumable tungsten electrode in order to deliver a weld. With stainless steel, this type of welding can be done with our without the use of a filler wire. Learn more about TIG Welding of Aluminum as well as TIG Welding of Stainless Steel.
• MIG Welding
  • MIG welding entails the use of a filler metal in the form of wire. This wire is fed through the welding torch and delivers a higher welding speed than that seen in TIG Welding.
• Robot Welding
  • The robotized MIG welding process, robot welding has its benefits in long production runs, helping to deliver an increased productivity. Do note however that problems can occur when using this method on workpieces with uneven gaps or workpieces that are very thin.
• Friction Stir Welding (FSW)
  • Commonly seen in aluminum fabrication, FWS entails the clean surfaces of aluminum parts to be heated through friction – this friction is created by means of a rotating tool – and then pressed together. This results in the formation of a new homogeneous structure without having to use a shielding gas or filler metal.

Final assembly is then completed by using various processes ranging from welding and riveting, to threaded fasteners, adhesives and, in some cases, more bending processes.

Note that you can learn more about aluminum assembly by visiting our Assembling Aluminum Parts page. You can also take an in-depth look at Stainless Steel Fabrication processes as well as Aluminum Fabrication processes.

Back to Main Page: Metal Fabrication

Further Suggested Reading:

• Metal Fabrication Tolerances
• Metal Fabrication Materials