A screw is a metal fastener with a helical thread used to join materials by rotating it into place. Screws are important in a lot of industries because they help things stay strong for a long time. Among the various types of screws available, bi-metal screws stand out for their unique structure and uses. This guide will introduce you to bi-metal screws, their definition, advantages, and the manufacturing process. We’ll also share why they are the preferred choice for many applications.

Definition: What Is a Bi-Metal Screw?

A bi-metal screw is a high-performance fastener composed of two different metals, typically stainless steel and alloy steel, followed by multiple manufacturing processes, heat treatment, and surface treatment. The definition of Bi-metal refers to a material composed of two different metals bonded together, featuring combined properties of both metals. By combining these materials, bi-metal screws offer the best of both worlds: the corrosion resistance of stainless steel and the strength of alloy steel.

The stainless steel is used for the screw head and body, which is impervious to corrosion. The alloy steel forms the tail for superior strength and penetration power. This makes bi-metal screws perfect for buildings and constructions in high erosion or extreme conditions.

The Manufacturing Process of Bi-Metal Screws

Here’s an overview of how bi-metal screws are made:

1.Head Forming (Stainless Steel):

The first step is to form the head of the screw using stainless steel. Molds are used to shape the material into the desired screw head form.

2. Welding:

The stainless steel head is then welded to the alloy steel tail, and an inspection process confirms the weld is strong and safe.

3. Pointing:

The tail end, made from alloy steel, is formed into the required shape using advanced forming processes.

4. Thread Rolling:

The screw's threads are created by rolling the workpiece, giving the bi-metal screw the threading necessary for its applications.

5. Heat Treatment:

Heat treatment is applied to enhance the firmness and hardness of the alloy steel portion.

6. Surface Treatment:

Finally, the screws undergo surface treatments like plating or painting to improve rust resistance and appearance.

Advantages of Bi-Metal Screws

Bi-metal screws have several advantages over traditional fasteners:

1. High Penetration Power

The alloy steel tail provides superior penetration ability. So, the screw cut through hard materials like metal and hardwood easily. They are particularly useful in dense substrates, decreasing extra effort and wear on tools.

2. Corrosion Resistance: 

Featuring a stainless-steel head, bi-metal screws perform well in areas prone to severe erosion, such as industrial settings, coastal areas, or areas exposed to chemicals. Suitable for outdoor areas with high corrosiveness and high salinity. They maintain their structural integrity under such conditions, guaranteeing a long lifespan in places where other screws may deteriorate quickly.

3. Quick Installation:

These screws are special fasteners that can drill and tap in one operation. This means the user doesn’t have to drill a hole first, which saves a lot of time and effort, especially in big construction projects. Using them also prevents damage to the materials working with, leading to cleaner and more precise installations.

Types of Bi-Metal Screws

There are several types of bi-metal screws, each made for different applications. Here’s a quick overview of the most common types:

• Stitching Screw:
  Used for fastening overlapping steel plates in supporting structures. It provides a secure connection, often used in roofing and cladding applications.

• Self-Drilling Screw:
  Performs three tasks—drilling, tapping, and tightening—in one operation. It features a drill-shaped point that allows it to drill its own hole and create threads in materials like metal.

• Sandwich Panel Screw:
  Ideal for fastening sandwich panels used in roofing and wall construction.

• Fibre Cement Screw:
  Used for attaching roofing materials like fiber cement boards. These screws have sharp self-drilling points and high-strength threads, allowing easy penetration into fiber cement without cracking or damaging the material.

• Wingtek Screw:
  Features wings at the tail, which break off upon penetrating steel.
  Once the wings reach the harder material (like steel), they break off, allowing the screw to anchor securely. This makes wingtek screws ideal for multi-material connections, such as timber to steel or composite panels.

• Concrete Screw:
  It’s a heavy-duty fastener designed for anchoring objects to concrete, brick, or masonry surfaces

• Stainless-Steel Plate Screw:
  A new product by K.TICHO Industries, this screw can directly tap into stainless steel plates, which is not common in the market.

Applications of Bi-Metal Screws

Bi-metal screws are widely used in construction projects, especially in structures exposed to rough conditions. Common applications include:

• Roofing, Wall, and Window Systems:

Bi-metal screws are great for holding together steel parts in different construction areas. Their strong penetration capabilities allow them to fasten metal panels to steel or wooden frameworks firmly. Moreover, they are resistant to corrosion, which means they can last a long time even when used outdoors, where rain and humidity might cause other materials to rust.

• Industrial Buildings:

Industrial facilities, such as factories, solar panel installations, and power plants, often utilize bi-metal screws for structural integrity. In these situations, the screws must resist not only high stress from heavy machinery but also the effects of chemicals and other industrial pollutants. Bi-metal screws are a dependable solution as they can endure both wear and erosion. For solar panel structures, in particular, bi-metal screws are used to mount panels on metal racks or frames in outdoor environments.

• Public Infrastructure:

Large-scale infrastructure projects such as airports, power systems, bridges, and coastal developments benefit from the strength of bi-metal screws. These projects often require fasteners that can hold heavy use, constant exposure to changing weather conditions, and potentially erosive situations. In power systems, these screws keep electrical equipment stays mounted.

Bi-metal screws bring superior performance where regular fasteners would rust or fail due to environmental stress. Thus, these screws are indispensable in both commercial and public infrastructure.

Your Trusted Bi-Metal Screw Manufacturer – K. TICHO

Bi-metal screws are important parts used in construction and various industries. They are strong, resistant to rust, and work well in challenging environments, making them an excellent option for projects that need reliable materials.

If you are looking for a bi-metal screw manufacturer, K. TICHO Industries is the best choice. K. TICHO Industries, a pioneer in bi-metal screw production in Taiwan, is renowned for its high-quality products that international partners trust. Notable projects such as Taoyuan Airport and the National Kaohsiung Center for The Arts - Weiwuying have successfully utilized K. TICHO’s bi-metal screws. We are professional in screw designing and manufacturing to tailor to the customer's needs. Founded in 1982, K. TICHO Industries offers expert bi-metal screw solutions to help you achieve business success. Please do not hesitate to contact us for further information about bi-metal screws.

▲Check out the introduction video of K. TICHO. K. TICHO is a bi-metal screw expert