BWI’s engineering team agreed to observe a joint demonstration by the
Yaskawa Motoman® and Miller Electric team. Several weeks before the presentation date, BWI Group supplied Yaskawa Motoman with the welding
brackets and tube assemblies to be welded. A team of automation engineers and welding experts, from both Yaskawa Motoman and Miller Electric, integrated technology and developed procedures for the application.
Fixturing to prevent components from being loaded incorrectly was designed and built on-site, and an expert from Hobart Filler Metals, Troy,
Ohio, was consulted to discuss alternative wire types. A general-purpose
welding wire, ER70S0-3 0.035 (90/10 gas) solid wire, was chosen.
After the welding demonstration, BWI moved forward with the customization of four Arc World® 1200 workcells to fulfill immediate application
needs at its production facility in Chihuahua, Mexico. Each customized
system features two Motoman MH12 6-axis robots configured for arc
welding to support the weight of a Vitronic laser seam inspection system
to monitor weld size, porosity, undercut, and crater fill. Every welding robot includes a Miller Auto-Continuum™ 500 weld package and a Miller
Coolmate™ 4 water circulator.
To enable each robot to verify that short structural welds are performed
within established limits, Miller Electric’s Insight Centerpoint ™ arc data
monitoring software is configured to monitor amperage and voltage and
integrated with the laser seam inspection system. This configuration helps
the robotic welding system track nonconforming parts unloaded by the
operator. An HMI operator station with pedestal mount provides a graphic
display that workcell operators use to monitor the weld sequence and
clamp status for each weldment.
Each cell includes two MHT-185 headstock/tailstock positioners, one
Binzel TCS-Reamer, one MSR-355 rotary positioner, and one hard-stop
kit. The headstock/tailstocks feature the patented MotoMount ™ fixture
mounting system to help simplify tooling and reduce stress on positioner
bearings. Yaskawa’s MotoCal™ software tool is integrated on each robot
to help improve positioning accuracy, tool control point, and tool posture.
Since summer 2018, the robotic workcells have been used at the Mexico
facility to weld a variety of suspension components for high-end struts and
shocks for multiple vehicle manufacturers. Each two-station system operates three shifts, five days a week. While seam tracking has added to the
cycle time of each part, the workcells have eliminated rework, improving
overall cycle time. And BWI is achieving the high weld quality demanded
by its customers, exceeding OEM requirements for safety-critical welds.
Robotic welding system helps chassis supplier
exceed OEM requirements for safety-critical welds
TECHNOLOGY » APPLICATIONS
BWI Group, Kettering, Ohio, a joint venture of Shougang Corp. and Bei-jing Fangshan State & Asset Management Co. Ltd., is a chassis supplier
and manufacturer of vehicle brake and suspension systems for the global transportation market.
Shortly after the company’s founding, BWI and its subsidiaries acquired the Chassis Division of Delphi Corp., which was formed years
earlier by General Motors. This auto industry experience and resources
helped the company establish itself as a technology provider for automotive, motorcycle, and specialty vehicle customers worldwide.
While BWI’s Validation and Test Development group performs fatigue
or “life” tests on each component during the development process to
ensure product safety, speed to market is equally vital to company success. For these reasons, weld quality and cycle time are key areas of
focus on the production floor.
In need of a second opinion about what equipment combination to
use for the incorporation of a GMAW system that would exceed original
equipment manufacturer (OEM) requirements for safety-critical welds
on thin-wall suspension components, the company reached out to Miller Electric Mfg. LLC, Appleton, Wis. Specifically, BWI wanted Miller Electric’s opinion on the ability to ensure OEMs that nonconforming parts
could be contained from production flow and that safety-critical welds
were within specified limits.
After initial meetings with BWI Group, Miller Electric weld and automation specialists suggested that Yaskawa America Inc.—Motoman
Robotics Division be consulted about designing a customized robotic