There are two main types of broaches: surface and internal. Surface broaches are designed to penetrate hard materials and are usually made of high-speed steel. Internal broaches are generally made of tungsten carbide, which is a tough and durable material. The two types are similar, but the former has many advantages over the latter. In terms of cost, high-speed steel is cheaper and is generally harder. Both materials will retain their sharpness, but carbide has the advantage of being more durable.
As with other cutting processes, broaching is an important part of high-volume manufacturing. In addition to rotary broaching, linear broaching is also a specialized form of broaching. In fact, there are different shapes for linear and rotary broaching. These can be used for various applications, from drilling to cutting. Broaching is a crucial process in high-volume manufacturing, but it is often overlooked. Here are some of the most common shapes created with these tools.
When choosing a material to broach, look for materials that are free-machinable. Steels with an Rc of 20 to 30 are excellent candidates for broaching. Those with Rc 35 or higher will require frequent tool changes and regrinds. The same goes for cast iron, malleable iron, bronze, and other metals. While the hardest materials are the most difficult to broach, many of these materials have a high tolerance for broaching.
Depending on the application, circular and helical shapes are used to create keyways. The radii of circular broaches are more similar to those produced by drill presses. However, the cut produced by a broach is more precise and can produce tighter tolerances. Despite these differences, round broaches are useful in mass production. They can also produce accurate holes in a very short time, which is why they are great for high-volume production.
Linear and circular broaches use a metal bar to create a shape in a workpiece. The linear broach contains many teeth, each slightly larger than the last. As the broach passes through the workpiece, each tooth removes more material, until the final tooth leaves the exact shape of the cut that the operator wants. The two types of broaches are similar, but the rotary broach is more versatile. In addition to rotary broaches, they are useful in the manufacturing industry. Shop broached items from Somma Tool.
Broaches have several different types of teeth. While each one is designed to produce a single shape, the broach has teeth for roughing, semi-finishing, and finishing cutting. A long tool has multiple teeth, each of which cuts a part only once. This allows a large number of parts before requiring resharpening. If the cutting process is performed with a straight blade, the resulting profile is smooth and even.
The internal and external broaching methods differ in their efficiency and application. A push broach can produce a round hole while a pull broach produces a square or hexagonal shape. In this way, it can cut keyways and slots in a fast and efficient manner. External operations, on the other hand, produce exact dimensions. These include flats, keyways, and contoured surfaces. A pull broach, for example, can remove material from the surface of an automobile cylinder block.
Horizontal machines are designed for pull-type operations. The tool is pushed through a workpiece by means of a pilot, and then pulled through by a hook. Horizontal machines require more room but are generally more powerful. They are useful for round, spline, and keyway broaching. If you have a horizontal broaching machine, be sure to read the manual carefully before buying one. It’s easy to make a mistake with a horizontal broaching machine – it could cost you a lot of money.
Surface broaches are designed for cutting surfaces, and are an excellent choice for complex keyways. Surface broaches are typically constructed with a solid piece of steel, but some types have a built-up design. They are often equipped with multiple sets of inserts. The advantages of this approach include reduced costs, flexible tool design, and changing the shape of parts. You can choose from two types of surface broaches, or choose one that suits your needs.