There’s a lot of work that has to take place before a welder can put on their helmet and fire up their welding gun. In addition to cleaning the metal – removing rust or surface imperfections – it’s necessary that the welder makes sure the two pieces will have a strong bond to become one piece. For a butt weld, a proven way to accomplish this is to bevel the end pieces of the material beforehand. After the pieces are lined up, then the void created by the bevel can be filled to form a strong butt weld.
A variety of bevel angles and shapes can be created, depending on the material. Typical bevel angles are from 30 to 60 degrees and can be specified as single angle or multi-angle bevels. For example, when welding thicker plates, the weld specs may call for a steep angle near the root of the weld and a wider angle at the top.
Understandably, the process of beveling plate or pipe can be accomplished in many ways: using handheld tools, machining centers, robotic machines, or flame or torch cutting. In some cases, the material size, shape and level of portability dictate the way in which the beveling will be carried out. And sometimes, the bevel type and size are the deciding factors for which tool to use.
Focusing on handheld tools, several types can be used to create a bevel. Some welders might be inclined to use an angle or die grinder or even a handheld torch. These methods, however, can result in a rougher, uneven surface or discoloration to the metal that can occur due to the high heat. Angle grinders create dust, throw sparks and typically require a long working time to get an ideal result.
In recent years, handheld beveling tools have revolutionized modern beveling. For starters, they’re offered in pneumatic and electric versions. And because they use indexable carbide inserts instead of an abrasive, they produce chips rather than dust and sparks, making for a cleaner and safer shop environment. Understandably, dust is dangerous to breath and sparks can present a fire hazard. In addition to increasing safety, handheld beveling tools are also flexible in the materials that they can handle.
In terms of ease of use, modern handheld beveling tools are easy to configure, ergonomic and portable and can save a welder time and money by creating a tightly joined area. In terms of safety, they produce less vibration and fewer sparks than a grinder. Also, there is less training involved when learning to operate a beveling tool than other traditional methods.
Unlike angle grinders or torch cutters, beveling tools don’t heat the base metal. This is a key factor that makes them the preferred method for heat-sensitive materials as the cold processing prevents structural metal change and the blue discoloration of the material that is sometimes associated with it.
Another advantage over grinding or torch cutting is that beveling tools produce a clean, consistent weld-ready finish, again, adding to the productivity of the process. The better the edge quality, the easier it is for the welder to produce a more consistent weld that requires less rework.
Just as there are several different types of tools that can be used to produce a beveled edge, there are also different types of beveling tools. In choosing which one is best suited for the job, as before, the application will be the final determination.
Beveling tools with a router-type base allow the beveler to work on external and internal edges as well as in jobs that need to follow shapes. But, the router-type option offers less stability to keep the tool flat to a surface. It also requires the replacement of the cutting head to change angles, which lowers productivity and increases costs. Another type of base that uses guide plates offers excellent stability on edges. However, it limits the use to external straight edges only. This type also allows for the guide plates to set the angle of the bevel, therefore eliminating the need for different cutting heads for each angle.
Features to seek
Several equipment manufacturers offer dedicated beveling tools, including Metabo Corp.’s three large beveling tool models. These tools offer optimum control when beveling straight cuts and when creating beveled corners. They are touted as being able to increase processing speed by as much as five times compared to using an angle grinder or torch cutter.
The tools also offer bevel angle customization from 0 to 90 degrees with a maximum depth of up to 5/8 in. at 45 degrees (or 1.25 in. at 12.5 degrees). The patented mechanical safety brake in the KFMPB 15-10 F model stops the cutting head in less than 1 sec., significantly reducing the risk of injury in the event the operator loses control of the tool.
Other features include an electronic package with overload protection, restart protection (preventing the tool from restarting on its own in the event of power interruption), soft start, speed stabilization and safety shutdown. The tools’ “one-touch” controller allows for precise (by an increment of 0.1 mm or 0.004 in.) tool-free depth adjustment that locks in.
Instead of a large cutting head, Metabo’s beveling tools use four-sided square indexable cutters available for carbon steels, stainless steels and aluminum. The large bevelers also include guide rollers that allow for the precise beveling of pipes.
Metabo also offers a corded and cordless compact model for working in confined spaces and to bevel internal edges or follow shapes. The compact model’s universal bevel cutting head can process 45-degree chamfers at 5/32 in. depth and radii at 5/64 in. and 1/8 in. Like the large bevelers, the compact bevelers have tool-free, precise adjustment of the cutting depth and integrated stopping points to adjust the cutting depth.
No matter if large or compact, Metabo’s beveling tools are powerful and fast and safe. They produce uniform, clean and consistent finishes, and the indexable carbide inserts can be replaced quickly. But overall, they allow welders to accomplish what they need to produce strong, long-lasting welds.