The most popular thread used in fastening is the machine screw thread. The machine screw thread has a 60 degree thread angle made in a continual running helix pattern. It’s primarily used with a nut or a tapped hole.
Screws for Plastic
Screws for plastics have a thread that is designed to be used in soft materials. It generally has a 30 degree flank angle thread that slices through plastic materials with out inducing high stress levels and offering high pull out performance.
Sheet Metal Screws
A screw consisting of a specially hardened thread allowing it to form its own internal thread when driven into sheet metal and other relatively soft materials. It is highly versatile, used in wood, fiberglass and metal, also called self-tapping screws. Available in steel and stainless steel.
Socket and Shoulder Screws
Socket screws have a machine screw thread and are made primarily in two materials, steel and stainless steel. The steel socket screws are made from an alloy steel and are heat treated to high tensile strengths. The stainless steel socket screws are generally made from 302 or 304 and are not heat treated.
Screws are a fastener used to secure materials by digging in and wedging into a material when turned. These tools are necessary for development and building in all industries. Screws are commonly made from carbon or stainless steel. PENCOM offers a variety of metal screws to suit the demands of nearly any application.
All screws have common features, no matter what their specific material or design may be. Common features among all screws include:
- Each screw is designed with a head at one end containing a special indentation or shape to allow use with a specific type tool, such as a screwdriver or wrench.
- The head of a screw is always wider than the body, allowing tools a surface to engage and drive the screws. The most common head types are Pan Head, which sit above the material, and Flat Head, which can rest flush for a smooth appearance.
- Most screws are tightened using a clockwise rotation; a counterclockwise rotation will release the screw.
- The threaded design of the screw enables it to sink into and grip the surrounding base material for a secure hold.
Types of Screws
Screws come in a variety of types. These screws vary in their design material and their thread type based on their designated uses and the materials they are expected to link together.
The machine screw is the most common and most versatile type of screw, designed with a straight, untapered shank and a blunt end. Machine screws are designed to be inserted into a pre-threaded hole or used in conjunction with a nut. These screws are typically intended for use with a manual or powered screwdriver.
Screws For Plastic
Screws for plastic have a varied design from common machine screws. These screws consist of a finer thread that is ideal for softer materials. These screws have the ability to go through plastic with minimal stress and low torque installation. The design ensures that the screw will not split or crack the base plastic material.
Sheet Metal Screws
Sheet metal screws, also called self-tapping screws, are specialized in function and in design. Their heads can come in either flat, oval, or hex shapes based on what is needed for the metal. Sheet metal screws contain a sharper thread than other screws, enabling them to cut into harder materials. Their design consists of a strengthened thread which is harder than the metals they are intended to screw into, allowing for an internal thread to form without breaking when driven into materials that are softer than the screw material.
Socket and Shoulder Screws
Another specialty screw, socket and shoulder screws provide space between surfaces. These screws are fabricated from strong metals such as steel and stainless steel, and consist of a head, thread, and shoulder.
Common Screw Applications
The applications for screws vary widely based on the type of screw. A few of the most common applications include:
- Machine screws are used for connecting metals to other metals, and for a variety of electrical connection applications. These screws are designed for strength and high duty.
- Screws for plastic may often be found in manufacturing facilities for consumer goods. Screws for plastic are designed to be used in many common products.
- Sheet metal screws may be used to connect a wide variety of materials, such as metal/rubber and vinyl/rubber combinations.
- Socket and shoulder screws typically see use in highly specialized applications. With a strict usage in the aerospace and consumer product industries, socket and shoulder screws are designed to meet significant strength requirements.
While screws offer a common solution to connect materials, PENCOM understands that our customers need high quality and performance from even the simplest of solutions. The quality of a product often depends heavily upon the quality of the fasteners that hold it together. Our engineers design all of our screws to withstand the expected rigors of their intended applications.
To learn how screw solutions from PENCOM can improve the quality of your products, please request your quote.