As International Truck and Engine Corp. developed processes for the manufacture of a high-performance truck (the International 4300/4400 medium-duty truck), company leaders decided that a new level of involvement was needed with employees and environmental, health and safety (EHS) representatives. This involvement was necessary to maximize efficiency, reduce waste and decrease health and safety issues.
Past truck launches were driven primarily by product engineering and facilities engineering leaders with little input from employees or their representatives. This time, however, International actively solicited the participation of employees, focusing on ergonomic and safety concerns. This focus contributed significantly to all phases of the new vehicle launch in March 2001.
There were two major elements of the 4300/4400 launch. First, a 323,000-square-foot cab assembly and stamping facility was built on the campus of the 2.5 million-square-foot Springfield, Ohio, truck assembly plant to manufacture the new cab. Second, every assembly department implemented changes to existing methods used at International facilities in areas such as material delivery, tooling, manufacturing methods and equipment.
To deal with this enormous change, multifunctional teams were assembled that included representatives from management, the union, production, materials, plant engineering, industrial engineering, quality, health and safety, plant layout, material handling and planning. Each department had its own team. The format of employee participation was different on each departmental team. There was no cookie-cutter formula dictated on how project leaders were to engage their teams and deliver the results. Therefore, each team drew upon the resources of the EHS representatives and the employee representatives in different ways. Several examples follow of how EHS and employee involvement impacted the development of the manufacturing process.
| Cab Trim Team: Rules of Engagement |
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Cab Assembly and Stamping Facility
The cab assembly and stamping facility (CAS) is the first truck assembly plant of its kind in the world. With four integrated hydraulic presses, more than 80 electric robots and the proprietary Integrated Body Assembly System, International is building truck cabs with tolerances without parallel in the truck industry. With all of the automation and technology, International's safety and health representatives had to be prepared to deliver safe and functional processes to the plant.
More than two years before the equipment would be delivered to the facility, project engineers engaged safety representatives to design safeguarding systems and robotic safety controls. At first, the represented workers were not brought in, but company managers soon solicited their
input. Once on board, the joint labor/management team that already existed in Springfield began to meet
regularly with project engineers, contributing to the safe launch of the new facility and its product.
The primary efforts of the EHS team at CAS were to simultaneously learn about robots and to influence the design of the robotic safety systems being developed for the new facility. For example, four EHS representatives, including the safety chairman for the union, went to Japan for a week to thoroughly inspect four major and several minor cab assembly robot cells containing more than 60 robots built in a prototype facility.
The team conducted checklist reviews to test interlocks, e-stops and other safety features. More importantly, however, the team stood back and observed, asked questions and tried to ascertain how employees might accidentally or deliberately bypass safety systems. Their suggestions ranged from adding additional guarding and more light curtains to changing heights of handrails and labeling each process warning light. All suggestions were documented, and at the end of the week, before leaving Japan, action plans were developed.
As the equipment was delivered and reassembled in Springfield several months later, the EHS group verified that the agreed-upon changes had been made and once again reviewed the system in its final setting.
The second major initiative was the development of machine-specific lockout/tagout procedures. This was a multidisciplinary effort involving safety representatives, production employees, skilled trades employees and system integrators from Japan. After several iterations, an excellent system was developed to ensure operator and repairman safety while minimizing downtime associated with implementing the lockout procedures. This was achieved by breaking down large robot cells into various types of energy sources, then providing color- and number-coded locks for each matching energy source for each line. The most complex line, the cab main, requires 95 locks (39 electrical, 19 pneumatic, 10 motor isolation, 23 water and four cab transfer units). All lockout locations are identified on the procedure by a layout drawing and at the locking device with a color-coded identification tag. Locks are numbered and color-coded to match the energy location so it can be quickly determined if a lockout has been missed.
Cab Trim Department
The cab trim department had a unique opportunity to incorporate ergonomics and safety into every station because it was the only line in the existing assembly plant built from the ground up. All of the other departments had to work around existing processes utilizing weekends and vacation periods to install and test new equipment on the assembly lines. In fact, cab trim would experience more changes than any other department in the assembly plant regarding product and facility redesign.
A 39-member team representing 19 functional areas and manufacturing support was charged with implementing a 500-foot straight production line. Truck cabs would be assembled with the doors off, which is uncommon in the truck industry. This enabled the team to place a heavy emphasis on ergonomic and safety considerations in the assembly processes. For example, with the doors off, mechanical lift assists could be used throughout the department for modules that would have been manhandled in the past. In addition, a dedicated door assembly line could be optimized to multiple working heights to fit the task.
The team included one union steward, two union ergonomics representatives, one union safety representative, 10 production employees and numerous other functional management
representatives from production, engineering, materials, quality, environmental and safety, etc. Positions and titles were checked at the meeting doors as team members were encouraged to participate in all discussions, and committees were formed to make the final decisions using decision analysis and problem-solving matrixes (see "Cab Trim Team: Rules of Engagement" on page 72).
Three key areas of employee involvement:
1. Cab dolly. After review of the new line concept, the team opted to modify the traditional cab dolly used to transport the cab on the assembly line. The dolly was set at maximum height to accommodate operators assembling parts to the front of the cab. Ergonomics and safety representatives chose this height to eliminate the "bending over" posture of employees on the existing assembly line where the cab is positioned lower. For installation of marker lights on the roof of the cab, the dolly permits the cab to be rotated 90 degrees toward a platform that allows the operator to perform the work at chest level in a safe manner instead of reaching up overhead.
The higher cab position on the dolly created a different problem for operators climbing in and out of the cab. The team developed lightweight, pullout steps positioned on both sides of the line. This reduced the climbing height on the existing assembly line from one 21-inch step to two 13-inch steps. The operators also have discovered the step makes an excellent low seat when performing work on the floor level of the cab.
2. Lift-assist devices. The cross-functional team met to analyze proposed solutions for each process that ergonomic surveys indicated would require a lift assist. One of the most complex devices is used to move the instrument panel module from a work table to the cab. The pneumatically controlled lift assist is used to pick up the module, insert it into a truck cab moving down the assembly line and tilt it into position on the firewall of the truck. The team solicited bids from suppliers, visited the suppliers to test the lift-assist devices prior to purchase and helped evaluate the installation of the devices.
3. Glass-bonding process. A robotic glass bonding process is used to apply urethane adhesive to the windshield and rear glass. A concern the team dealt with during the design of the cell was how to clean the tips when the
adhesive begins to build up. One suggestion was the use of an air knife. When the team benchmarked another International location in Canada, however, it found that this method would atomize isocyanates from the adhesive. The team decided to clean the tips by moving them across a taut strand of wire instead of blowing them with air to knock off excess material. This eliminated employee health concerns about excessive isocyanate exposures.
The objective at the outset of the cab trim project was to implement a "world class" line, designed for manufacturability and conscious of safety and ergonomics. The vision was to create a working environment in the cab trim department that was unparalleled at the plant for quality and operator satisfaction. Team members agreed that when the United Auto Workers (UAW) and the management team combined expertise, experience and dedication to the success of the project, the result was the delivery of a new production line that allows the operators to operate in a safe and ergonomic environment, allowing them to focus on delivering a quality product.
Final Assembly Departments
The final assembly departments' process changes were primarily directed at parts presentation and lifting. Several subassemblies were purchased as large modules instead of individual components. Specialized racks were designed so that when the operator removed the parts from them, he did not have to bend too far over, reach too high overhead or use too much force.
The UAW ergonomics representatives and rack designers worked closely with vendors and group leaders to build the right racks for the job. Prototype racks were built, and group leaders and ergonomics representatives traveled to the company's engineering and process evaluation center where prototype equipment is first tested. They took turns loading and unloading the racks and providing feedback to the designer. Several unique racks are now in use in the department that best position the parts to the worker. Employee input even influenced the design of the battery box module so that it would be easier to install with a lifting device.
Employees continue to provide input that yields improvements in ergonomics and safety. Two months after the initial launch, for example, employees worked with the tool engineer to develop a power tool that eliminates excessive hand and wrist bending during the attachment of the park brake cable.
Conclusion
Participation by affected workers in UAW Locals 402 and 658, and by their safety and ergonomics representatives, ensured that diverse ideas from many perspectives were used in the design of the medium-duty truck and the assembly processes. Employee considerations were an integral part of the manufacturing process development.
Employee productivity has increased at the same time that incident frequency rates for the new and modified process departments have decreased. IFR is running about one-half of the historical rate in these departments. In addition, the quality measures have improved dramatically, too.
These examples of employee participation in the launch of the high-performance trucks demonstrate that International has achieved a new level of environmental, safety and ergonomics performance. More importantly, it has set a new internal starting place so that during the 2002-year product launch, the input will begin earlier and continue throughout the process. This high performance will increase ownership of the process and reduce injuries, defects and waste in the assembly process.
Tim W. McDaniel, CIH, QEP, CHMM, is the environmental, health and safety manager of the Springfield Assembly Plant of International Truck and Engine Corp.