Screw Machine Products

About Screw Machine Products and Screw Machine Product Manufacturers Including: CNC Turning, Knurling, Precision Turned Parts, Screw Machine Parts, Swiss Screw Machining, Thread Rolling & Threaded Rod.

Screw machine products include a wide range of parts formed by turning, a rotary machining process in which stock metal rods are threaded, drilled, slotted, milled, knurled and tapped into precision application parts. Although specialty screws and fasteners are a common product manufactured by screw machining, also known as "swiss screw machining", other types of turned parts have crucial applications as precision medical tools, automotive tools, laboratory tools, electronics components, appliance components, military parts and many others. Screw machines may be mechanically operated by cams, or they may be controlled by fully automated CNC; both types of machines offer diverse capabilities, such as thread rolling and knurling. CNC turning, accomplished by CNC screw machines or CNC lathes, may machine up to 6 parts simultaneously, and screw machining is considered one of the fastest and most cost-effective methods of small rotary part manufacturing.

Screw machining offers design capabilities and structural benefits which cannot be cost-effectively reproduced with any other manufacturing method. Specialty fasteners, metal knobs, miniature medical instruments, bio implants, tire gauges, threaded rods, splines, spindles, fittings and a limitless variety of custom metal parts can be machined to precision tolerances by turning. Not only can metal parts be shaped by screw machining, but they may also be surfaced; turning can produce a smooth, near-polished finish or it can produce a knurled finish. Knurling is the process of creating a patterned texture on the surface of a metal to provide grip; common knurling applications include tool handles, metal flashlights, knurled nuts and knurled knobs. Knurled patterns are achieved with specialized CNC turning tools.

Both lathes and screw machines are used to produce screw machined parts, although screw machines are capable of carrying multiple spindles, unlike lathes, and are therefore more commonly used for mass production. Screw machines are also known as Swiss screw machines due to their original invention in Switzerland in the 1800's. They may have more than 8 spindles which all operate simultaneously; round, square or hexagonal metal bar stock is attached to the spindles' spring collets, which spin as multiple automated cutting, drilling, notching and knurling tools attached to the screw machine work the bar stock into parts by shaving away excess material, smoothing and drilling. The main drive shaft of a screw machine provides power to the machine bed's lead work shaft and controls the two front cam shafts. The machine motor, located at the base of the machine, is the central power source for all operations and will vary in horsepower, depending on the size of the machine, speed and stock to be machined. Virtually any metal may be manufactured by screw machining; common screw machined materials include steel, stainless steel, brass and aluminum. Titanium is often used for sanitary and miniature medical tools.

CNC screw machining and CNC turning, have greatly expanded on lathes' manufacturing capabilities. Not only are screw machines capable of machining several parts simultaneously, but they also achieve high production rates, making it possible for manufacturers to make a large number of uniform precision machined parts with very little process time. Unlike manual lathes and non-CNC machines, multi-spindled CNC screw machines require a lengthy set-up process involving part design and system programming, including CAD design. For this reason, long runs are typically most cost effective, although no dies or hardware must be created custom for custom screw machine parts, making even short run screw machines a relatively cost effective means of precision production. Very few other metal forming and metal fabrication processes come close in precision to screw machining; some types of metal stamping can reach tolerances close to those of screw machined products, but for the extremely small, precision tools used in critical medical applications, screw machining is the only practical means of manufacturing.

Screw Machine Products and Screw Machine Product Manufacturers Images Provided by H&R Screw Machine Products, Inc.

Types of Screw Machine Products

• Automatic screw machine parts are complex parts that are often cylindrical and/or threaded. Automatic screw machines produce these parts at high speeds.
  
• High precision screw machine products are produced to extremely close tolerances, which is particularly useful when producing large volumes of turned parts. Close tolerances are achieved through the use of high-grade metals and close inspections during production stages.
  
• Medical screw machine products are used in a variety of applications in the medical, scientific and pharmaceutical industries. Precision medical components include spinal implants, screws and dental implants.
  
• Screw machine parts are usually cylindrical and threaded products.
• Screw machine products are manufactured by screw machines.
• Screw machining is a manufacturing process that can turn out several identical products at the same time.
  
• Stainless steel screw machine parts provide superior corrosion and chemical resistance. Stainless steel screw machine products are useful in industrial applications in which they will be exposed to temperature extremes, moisture and chemicals.
  
• Swiss screw machine parts are produced to very close tolerances. Swiss screw machines are often used in the production of small, complex parts.
  
• Threaded rod is a fastening bar with a twisted grove along its length.
• Turned parts are parts with extremely tight tolerances that are formed by loading bar stock into a screw machine and then machining the parts as the bar is fed through the machine. The vast majority of turned parts are formed by this process.

Screw Machine Products Terms

Acorn Die - A threading die used in screw machines whose cutting portion has a shape similar to that of an acorn.

Broaching - A machining process in which the interior and exterior surfaces of a part are altered to meet design requirements by the pushing or pulling of a cutter, called a broach, through the part surfaces. Broaching is particularly advantageous when machining complex parts.

Button Die - A tiny, adjustable die that is supported in a ring holder. Button dies are used in screw machines and for other work of the same type.

Cams - The components of a screw machine that move the slides and turret in order to feed cutting tools to the work. Cams control the automatic movements, depth and duration of every cut.

Chuck - The part of the lathe of a screw machine that grips the part to be turned, holding it in place while it is rotated and shaped.

Collet - A type of chuck on a screw machine that provides a solid grip on the turned part. A collet holds the part in place during rotation without leaving any defective marks on the part.

Cross Slide - A cam-driven slide that carries tools at right angles to the spindle. Cross slides operate through levers to give each tool the proper feed.

Lathe - A screw machine tool onto which a part is placed and rotated in order to shape it.

Mechanical Safety Clutch - A device that protects the mechanisms of a screw machine by disengaging, in order to stop the main drive shaft in the event of overloading or jamming.

Milling - A machining process that involves the shaving of a layer from the metal part.

Precision Machine Screw - A slotted, machined screw that is milled from bar stock. The thread is then cut and the screw is machine-finished.

Screw Stock - Typically, a free-machining type of alloy, in the shape of a wire or rod, that is used to form screw machine products.

Spindle - A screw machine part that consists of a rotary shaft about which a screw machine part rotates.

Turning - A machining process, used to form screw machined parts, in which a blank is rotated about a stationary piece of equipment.

Turret - A component of a screw machine that is driven by cams to bring each tool into position automatically.