Screws are one of the most common fasteners used in the world. It offers the most effective and easiest way to join two or more solid objects together. A screw is commonly self-threading/self-tapping, known as male thread or external thread which has helical threading on the external surface of the long shaft. It usually will have a head on one end that allows it to be turned with the tools like screwdrivers or wrenches. The head of the screw is bigger than the body of the screw as it will provide a bearing surface on the object. They are different shapes of screw heads available such as pan head, button head, round head, truss/mushroom head, flat/countersunk head, and oval head. Screws are popular to be used where the objects are seldom dismantled, or where the objects are thick enough and have sufficient strength to accommodate threaded holes and screws.
Screws can be made of a variety of materials. Screws made of titanium are hard, strong, light, and corrosion-resistant. it can provide greater strength and durability when alloyed with other materials. Other materials like stainless steel, plastic, brass, and aluminum also can offer a great level of corrosion resistance. Screw that made of copper can provide better wear resistance and load capacity. Some screws made of plastic are cheaper, suitably used for a light load, and the place where has direct contact with the water such as water pools. Whereas, screws that made of Molybdenum has a very high melting point which is suitable for some extreme environment. Other finishing such as zinc coating, chrome coating or black oxide coating may apply to the screws to provide a better appearance and extra protection.
If you are going to use screws for your works, you need to be careful about the type of screw you choose. A wrong screw will not only make the joint less reliable but will also reduce the longevity of the objects that you are trying to fasten. Here we will introduce few common types of screws and their applications in our day-to-day life.
Wood Screws
Wood screws are the most common type of screw that is used to connect two or more wooden objects or other soft materials. It has a coarse thread, tapered head, unthreaded/smooth shank, and a sharp point to dig into the wood. It is popular to be used in woodworking projects. The design of the wood screw allows the screw to penetrate through the wooden objects smoothly without causing too much breaking. Wood screws are normally made of stainless steel or brass material. There are available in oval, flat, and round heads. Round head is the most visible type and suitable for decorative purposes.
Sheet Metal Screws
As the name suggests, sheet metal screws are used for driving into the metal sheet. Sheet metal screw is fully threaded, has a flat/hex washer head and sharp point which allow it to dig into the metal sheet. The full thread design increases the retention between objects and its sharpness allows it to cut into the object and create the internal thread easily. There are two types of sheet metal screws which are self-drilling and self-tapping. Self-drilling screw uses its drill point to cut into the object that has not been drilled. A self-tapping screw is to fasten the objects with pre-drilled holes. Sheet metal screws are available in a variety of sizes, types, and materials. We choose the material type that matches the base material. Sheet metal screws can also be used for securing multiple objects together such as plywood, rubber, or plastic.
Machine Screws
Machine screws can be found in all kinds of machines, engineering tools, or other machining applications. It is used to hold heavy-duty metals and joint machine parts together. Machine screw has finer threads and is stronger than other average screws. It can be used for almost every material such as steel, brass, or nylon. The size of the machine screw is normally smaller than other standard screws, but it also available in larger variations for specific applications.
Lag Screws
Lag screws are also known as coach bolts. It is large, has at least 1/4 inch thicker and 1 inch longer than ordinary screws. A lag screw is extremely sturdy and able to withstand intense load which makes it suitable for connecting heavy materials such as heavy lumber. The Lag screw is only available in hex head that can hold up in the application where requires a lot of torque. A pre-drilled hole at the same diameter as the screw shaft is required for the installation. Lag screws are available in stainless steel, with zinc coating or hot-dip galvanized.
Cap Screws
A cap screw has an external thread on the shaft and the diameter of the head is larger than the threaded shaft. Cap screw is popular to faster machine parts like our home appliances, electronic devices, etc. It is normally used without the nut and tightens into a tapped/threaded hole directly. Cap screws can be made of carbon steel, stainless steel, and other alloys. The head type also available in the button. Hex, socket, etc.
Drywall Screws
Drywall screw is popular among contractors or homeowners for installation of drywall panels. The head is designed to countersink/flat without damage to the drywall. Standard drywall screws are only suitable for installing the drywall over wood studs, it is suggested to use metal-rated screws when working with metal studs. The drywall dimple bit is required for drywall installation as it may not be included in the standard drill set.
Security Screws
Security screw was also known as tamperproof screw, an excellent option for security application. It was used where requires additional protection against being removed easily. It has a unique head design that common tools are unable to remove the screw. A specialized tool like a square driver or spanner is required to remove it. However, the driver bits used to remove these security screws are available everywhere in today’s market. This kind of screw has no longer be considered a tamper-resistant screw.
MecHero Malaysia supplies different types of screws for meeting your requirements. You can always contact us at +6011-7000 7687 or email us at my.mechero@gmail.com for an inquiry about the screws for industrial or home use. As a steel and online hardware store Malaysia, we also supply a wide range of steel material, general hardware, or mechanical components. Tell us your requirements now and we can advise you accordingly.
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