Above: The Steelmax PB10 pipe beveling machine is designed for portability and can be used by a single operator.

Bevels are the foundation for high-quality welds

April 2019 - A 21st-century welding shop has many new and innovative technologies at its disposal to help improve productivity. Advancements in process control, automation, filler metals and shielding gases have come at a rapid pace. Implementation of these advancements can lead to significant cost savings, improvement in quality and reduction in rework. Even with these advancements, however, basic welding fundamentals remain key to a successful operation.

Weld preparation is one of those fundamentals which, if not approached properly, can lead to numerous problems. If the beveling process is not carefully considered, the costs of welding will rise, leading to lower productivity and smaller margins. Achieving complete joint penetration welds requires accurate and consistent bevels that fall within the groove preparation tolerance. Inaccurate bevel geometry can create costly problems. Lack of fusion and penetration, burn through, under filling and over welding can all result from a poor beveling process. For welding processes that will be automated, high-quality, consistent bevels are even more crucial.

There are several different methods used to prepare single- and double-V groove joints for welding, and some of these methods are more advantageous than others.

Pluses and minuses

Grinding bevels with fiber wheels is common in many shops. This process requires little capital expenditure. Electric grinders are inexpensive, and a Type 27 fiber wheel costs just a few dollars. The downside to this method is that it is slow, inaccurate and labor intensive. When not properly controlled, grinding can lead to inaccurate and inconsistent bevels. This method also presents some very serious safety concerns. Grinding wheels may generate hazardous dust that can harm workers while disintegrating wheels can cause physical injury to the operator.

Oxy-fuel or plasma burning are faster methods of beveling compared with grinding. When used in conjunction with automation, they can be very productive. They are not, however, without shortcomings. Burning requires a higher level of skill. Achieving quality double-V-groove bevels with these processes can be challenging. Kerf, torch position and torch angle can create variations in the root face dimension that often lead to problems with weld penetration. Thermal cutting can also produce surface oxidations, decarburization and a heat-affected zone (HAZ), all of which require secondary grinding operations to prepare the material for welding.

Creating bevels by milling has always been the most advantageous method of beveling. Milling machines create precise, uniform bevels without producing dust or a HAZ. The bevel is weld ready and requires no secondary operation. Until recently, milled bevels were a luxury that involved the use of vertical mills and CNC machining centers. The cost for this equipment required large capital expenditure, putting them beyond the reach of many shops.

Solutions for every job

Many new options are available in portable beveling tools. These tools require limited skill to operate and are relatively inexpensive to purchase and use. Steelmax offers an extensive portfolio of portable beveling tools for both plate and pipe applications—from handheld machines to large automated stationary systems—and can help customers find a beveling solution for almost every job.

Steelmax’s beveling tools produce high-quality, repeatable bevels, giving the fabricator consistent fit-up from part to part. This allows users to significantly reduce over- and under-welding from inconsistent fit-up and users are able to reduce defect rates. The tools help achieve these results while also increasing throughput by allowing workers to prep more plates or pipes each day, making fabricators more productive and ultimately more profitable. 

Steelmax Tools LLC
Centennial, Colorado
877/833-5629