Lean Manufacturing – and Standardization with the Axcess® Multi-MIG Welding System – Streamlines Production at Vermeer
Vermeer and Miller Team Up For Lean Welding
The most successful manufacturing organizations in America speak a new language: the language of LEAN manufacturing. Corporations that live LEAN daily use words such as one-piece flow, 5S, kaizen, poka-yoke, empowerment and Takt time as part of an overall philosophy that sometimes is misunderstood. “Lean” is simply a manufacturing concept designed to provide the optimum framework for efficient, competitive production. The lean production system is a management philosophy that embraces all aspects of industrial operations by focusing on the reduction of waste from the value stream in order to remain competitive in a world- driven economy.
Historically, welding-intensive organizations have adopted new techniques and technology more slowly than other industries. As a result, these companies approach welding, fabrication and assembly the same old way: inefficiently.
So that the welding industry can benefit, Vermeer Manufacturing Company of Pella, Iowa, and Miller Electric Mfg. Co. of Appleton, Wis., have agreed to share information from their lean welding journey. Vermeer’s results speak volumes to the power of lean welding. Here are just a few examples:
- A production rate increase of 37.5 percent on its “lean model line” (the line that best exemplifies lean principles. It produces brush chippers).
- The ability to turn raw materials into finished goods in days, not weeks. Vermeer has demonstrated year-after-year improvements of 200 to 300 percent for four consecutive years on some lines.
- Year-after-year safety incident and severity rate reductions of 10 to 15 percent.
- Zero long-term corporate debt. The company paid cash for more than 300 Axcess® multi-MIG welding systems from Miller.
- After implementing Axcess Systems and lean principles on its terrain leveler line, the number of non-conforming welds caught by internal audits dropped by 500 percent, from 6.68 to 1.36 welds per measurement period.
Vermeer employs approximately 2,000 people and is a worldwide leader in the design and manufacture of industrial construction, environmental and agricultural equipment. Some of its best-known products include brush chippers, trenching and trenchless equipment, terrain leveler surface excavation units and round balers.
Vermeer is known for taking care of its customers with better solutions, and for its 4P philosophy: principles, people, products and profit. This philosophy drives all company activity. Visit Vermeer.com for details.
Vermeer defines lean manufacturing as a time-based strategy that focuses on lead time reduction through waste elimination in every area of production, including customer relations, product design, supplier networks and factory management. The goal is to produce what the customer wants, when they want it, at the highest quality while being productive and safe. Lean encompasses five key measurable elements: quality, cost, delivery, safety and morale.
Miller Electric (MillerWelds.com) is a worldwide leading manufacturer of welding and cutting equipment and systems and employs about 1,450 people. As a wholly owned subsidiary of Illinois Tool Works (NYSE: ITW), Miller is well known for its success in implementing ITW’s philosophy, which aligns very well with lean concepts. The philosophy is led by the Pareto principle of 80/20, which provides focus. Focus leads to simplification in process and product flow by empowerment of the people at the right level in a flat, responsive organizational structure.
|Vermeer’s custom-built welding stands reduce the welding equipment's footprint and nearly eliminate cable clutter. Raising the welder off the floor greatly reduces the amount of contaminants that could enter the welder, too.|
These processes are really about simplifying and focusing on the key parts of a business. Simplicity focuses action, while complexity often blurs what is important. The process of simplification includes finding ways to simplify product lines, customer and supply bases and business processes and systems. In the end, 80/20 improves quality, productivity, delivery, innovation, market penetration and, ultimately, customer satisfaction.
Many Products, One Process
Vermeer’s lean journey started about eight years ago, with lean welding becoming an emphasis in 2003 when the company committed to using a single process (solid wire pulsed gas metal arc welding, or pulsed MIG) for all of its production welding. At that time, about 40 percent of its 220 production welding stations used pulsed GMAW. Also at that time, the company used eight different models of welders from at least three different vendors.
Vermeer’s first steps in lean welding were to standardize on one process for all production welding, reduce the number of welder models from eight to two and select a lean welding partner.
Standardizing on new welding technology would provide numerous process-related benefits, such as:
- Eliminating variability in primary power fluctuation (with Auto-Line™ technology)
- Ability to limit or “lock-in” functionality within scope of specific requirements
- Visibility to quickly change and view program numbers
- Multi-MIG process capability using one wire and one gas
- Ability to weld thick or thin metal
- Improved travel speed
- Less heat input
- Better puddle control
- Reduced distortion
- Less spatter
- Improved arc stability
- Reduced undercut
In the old school of welding, achieving these benefits would be the end game. At Vermeer, they were just the beginning. Standardizing on one product and process would also:
- Simplify welding training.
- Provide flexibility to deploy welding talent in different areas.
- Improve operator performance (higher production rates with fewer errors and better morale).
- Eliminate sources of variability between welding stations and shifts.
- Simplify and streamline maintenance by greatly reducing parts count; maintaining 300 welders of the same design enables maintenance to become very proficient.
- Change the typical vendor-supplier relationship into a vendor-partner relationship where each party contributes more to the value chain and benefits accordingly.
Selecting a Partner
The stereotypical relationship in many industries involves customers, equipment manufacturers and distributors haggling with each other over price. Anticipating the point of negotiation often inhibits each party from understanding each other’s needs, goals and long-term objectives.
To select a new welder, Vermeer welding engineers, operators, area managers and maintenance managers evaluated several different systems and suppliers over a period of months. They evaluated the welding systems on such traditional criteria as arc performance, reliability/robustness of design, ease-of-use, ease-of-maintenance and flexibility for future enhancements.
There are differences between various welding systems on all of these criteria; some differences are small, others are much larger and very solid reasons to select one particular product over another. In fact, the newest generation of welding technology can potentially save manufacturers thousands of dollars per day by solving productivity and quality issues that have not previously been solvable (visit MillerWelds.com/AMS for details).
However, evaluating “what’s inside the box” was just a start. One of Vermeer’s core objectives was to align itself with suppliers that embody similar lean principles. A cross-functional team of five Vermeer personnel visited Miller and learned that, according to the author, “Miller is doing many of the things that Vermeer dreams about in our lean journey.” These include:
- Supplier-managed inventory
- Daily on-line inventory replenishment
- Building to a customer order, rather than to a short forecast
- Ability to build and ship products in one day
- Same-day shipping of replacement parts
- Some circuit boards built in-house
- A flat, responsive organizational structure
- Employees at all levels empowered to make decisions
- Line employees engaged in managing their own business areas
One day prior to visiting Miller, Vermeer placed the order for the first 10 of its 300 Axcess Systems as a test trial. The next day in Appleton, Vermeer personnel then watched those 10 systems being built and shipped to Pella. Ten units were simply part of the trial process. To Vermeer, this signaled that Miller controls the cost of goods sold because Miller does not build up excess inventory (the number of days it takes to convert raw material into finished product is a key lean measure).
To “flatten” the maintenance process, Vermeer’s maintenance manager Mike Profit and several technicians attended Miller’s service technician training program and became fully certified to perform all maintenance procedures themselves (as opposed to a third-party authorized service provider, which is the industry norm). Being certified enables Vermeer’s maintenance department to manage the welding equipment for optimum performance, and it lowers maintenance costs. For more intensive technical assistance, Vermeer personnel have a dedicated contact at Miller’s Advanced Manufacturing Systems group and his direct phone number.
While welding system performance is important, Vermeer placed even more value on finding a responsive welding partner with similar organizational philosophies, structures, objectives and goals. This type of relationship, where both parties are aligned for mutual success, enables the parties to better manage the challenges that arise with any product’s use.
For example, Vermeer wanted its welding systems to track arc-on time, a critical measure of productivity for the welding operators and area managers. Without the ability to establish a benchmark for arc-on time, Vermeer would not be able to measure improvements or implement kaizen.
Unfortunately, this ability did not originally exist in the welding system’s software. However, because of the partnership arrangement, Vermeer felt comfortable requesting this capability, and Miller accommodated it. Miller engineers wrote an arc-on time program and e-mailed the program to Vermeer, who then updated the welding system’s software using a standard Palm™ device. This enhancement, which took less than two weeks to develop and implement, is now standard on all Axcess welding systems sold, providing a new kaizen tool for all Axcess users. This demonstrates how both customer and supplier needs can be met by working closely together.
|Boom-mounted feeders create a 30-ft. work envelope.|
Lean Welding Stations
To install its new welding systems, Vermeer’s maintenance department designed and custom built its own welding stands, which reduced the welding equipment footprint to just 9 sq. ft. On the “lower level” of the stand is a 900-lb. drum of wire. Compared to 60-lb. spools of wire, the 900-lb. drum provides a 15-fold reduction in the need to stop welding because of an empty spool. A gas manifold system delivers a constant supply of shielding gas, completely eliminating the need to swap out empty gas cylinders, another common source of “waste” that can be eliminated.
The Miller-supplied AA40G wire drive motor assembly feeder is mounted on a 15-ft rotating boom, designed and built by Vermeer. A boom-mounted feeder, coupled with a 15-ft. long welding gun cable, enables the operator to weld at any one of several fixtures within a welding area or easily move around a larger weldment. The stand and boom-mounted feeders nearly eliminate the “cable clutter” often associated with welding stations. Cable clutter presents a tripping hazard, and cables lying on the floor get damaged more easily and frequently. A boom-mounted gun also reduces operator fatigue, as the boom takes up some of the weight of the gun (for those who hold an object for hours a day, lightening the load by even a fraction of a pound is a big relief).
Each welding stand also incorporates Vermeer’s signal light system, which has five lights that enable operators to indicate the following:
Green = All is well
Blue = Bring a paint cart to move finished components to the paint line
White = Quality problem that requires an area manager’s help
Yellow = Material shortage. The operator needs more parts
Red = Line down. The operator can’t work because they need help or parts
At Vermeer, welding operators remain in the welding area and focus on welding. They do not chase parts or supplies, and they do not bring in unfinished components or remove finished parts. These activities are the responsibility of a “water spider,” a person who focuses on maintaining material flow between work areas so that welders, fabricators and assemblers can maintain their Takt time (see end of story).
Each welding station operates on a cart system. The welder has the components for the part/machine he or she is working on now, as well as components for the next one. When a cart is emptied, that signals the water spider to bring a new one. Further, each cart is numbered according to its specific station.
Pretend cart W3C is for the model BC1000 brush chipper tailgate. The metal fabrication area loads all the components for the tailgate on cart W3C, and a water spider brings it to a welding station. When welded, the tailgate goes back on cart W3C and a water spider moves it to the paint line. The painted tailgate then goes back on the cart, and a water spider then moves the cart to the point on the assembly line where the tailgate is added to the chipper. By adopting the cart system, Vermeer greatly improved its parts organization and presentation and eliminated the source of many mistakes.
In many organizations that perform arc welding, operators are required to consult a book of welding procedures or their work instructions. Older-style equipment relied on the operator to set individual parameters; in fact, operators often had free reign over the full-scale welding parameters. With full-scale unlimited range, most possible combinations would not produce acceptable results.
To eliminate sources of error and variability, Vermeer labels each welding system interface with the appropriate programs and parameters for each particular part or material thickness (see photo next page). To begin welding, the operator first selects the program that matches the welding wire diameter being used (the Axcess System stores and recalls multiple programs). Then the operator sets wire feed speed, voltage and arc length (“trim”) to match the metal thickness. Vermeer enables its operators to adjust these variables within a certain range to accommodate individual preferences, but it uses the welding system’s software capabilities to lock operators into an acceptable parameter range.
|This station embodies lean welding principles. Each tool and piece of equipment has its own, clearly labeled place. The weld table uses a scissor mechanism that presents the work to the operator at the appropriate height, which reduces stress, a potential source of operator error.|
Unlike older welding technology where individual machines could produce different arc characteristics, every software-driven Axcess System welds the same. Further, the system features Auto-Line™, a technology that compensates for variations in primary power (the voltage spikes, dips and low- or high-line situations common in many large facilities or companies with multiple facilities). As long as the primary voltage remains within a 190 – 630 VAC range, even if it fluctuates wildly within that range, the Axcess System will produce the programmed welding parameters.
By maintaining consistency between welding systems, Vermeer can deploy welding operators to different lines or different buildings without any need for additional system training or fear of introducing welding variability.
Nearly all Vermeer welders use an auto-darkening helmet, which switches from a light to a dark state in 1/20,000 of a second after sensing the welding arc. Compared to traditional fixed shade helmets, an auto-darkening helmet eliminates the need to raise and lower the helmet between welds. This saves several seconds between welds, which quickly adds up to several minutes on larger components (which can have 100 or more small tack welds to hold components in place before finish welding). Saving these minutes enables Vermeer to more easily adhere to its Takt time.
In addition, auto-darkening helmets reduce neck fatigue because operators no longer need to snap their head to drop the hood down. To encourage operators to use an auto-darkening helmet (which cost $300 or more for a professional model), Vermeer splits the cost 50-50 with the operator, and the operator owns the helmet outright after three years. To make the helmets easy to purchase, Vermeer’s welding supply partner, Wright Welding Supply of Des Moines, maintains an on-site employee, as well as inventory, at Vermeer’s Pella location.
Weld Area Organization
A closer definition of the Japanese usage of kaizen is “to take apart and put back together in a better way.” Vermeer’s welding areas look and function radically different now than they did just two years ago.
To further consolidate space and reduce operator movement, Vermeer developed multi-sided fixtures. One jig now performs the work of three. Another fixture holds and rotates a 2,200-lb. component with a simple gearbox (see below), enabling the operator to orient the part for welding in the best position.
|By labeling each Axcess welding system interface with the correct program and welding parameters, Vermeer eliminates sources of errors and variability.|
In the past, Vermeer did not believe that it was financially feasible to build fixtures for low volume parts (often the heaviest ones). These parts were built with more of a “job shop” mentality where components were brought in and laid out by hand with a tape measure and square. This practice introduces variability with measuring and squaring; further, parts that were just tack welded in place could come out of true when flipped or moved.
Since being involved with lean manufacturing, Vermeer has learned about the cost of quality associated with rework and defect parts (and that’s just flaws caught with an internal quality check). A flaw in a large piece of construction equipment used overseas doesn’t just cost Vermeer thousands of dollars to fix; downtime can cost the end user thousands of dollars per minute, which may result in a lost customer to Vermeer.
Today, Vermeer clearly understands that building fixtures reduces overall cost and improves safety. The company “can’t afford not to build them.” Further, the company has just embarked on designing fixtures with poka-yoke, or “mistake proofing” techniques. In Vermeer’s welding operations, this would be where a fixture allows an operator to load and orient parts one way: the right way. Poka-yoke fixtures completely remove the tape measure and square from the process.
|This simple gearbox rotates a 2,200-lb. component and increases safety because it eliminates the use of a chain and hoist to flip the component. By using poka-yoke, the fixture reduced welding time from two-and-a-half days to less than one day. Shown (L-R) are Vermeer’s Scott Beary, welding production manager and David Landon, manager, weld engineering.|
Before building the gearbox fixture and using poka-yoke, the part took two-and-a-half days to weld. It now takes less than one day. On one particular heavy equipment line, this lean technique and others reduced lead time from nine to five days—all while incorporating the ability to simultaneously build different models with different options, including paint color.
Lean production uses Takt time as the amount of time it takes to produce a completed product, and it is based on the average rate at which customers buy that product. Thus, Vermeer builds its products at its Market Rate of Demand (MRD, commonly called “the pull system”). If a facility has “leftover time,” it uses that free time to work on product or process improvements.
|Scott Beary and David Landon review the “Welding SQDCM Board.” This board tracks Safety, Quality, Delivery, Cost and Morale, the five areas that encompass Vermeer’s definition of lean.|
Producing according to Takt time is counter-intuitive to traditional manufacturing engineering, which focuses on equipment utilization. Engineering schools train students to think, “This piece of capital equipment is a huge investment, so you want it running 24/7.” Such a manufacturing approach does not necessarily create good material flow through the factory. In fact, it is often counter-productive to lean manufacturing because it creates excessive work-in-progress (WIP) that clutters the factory floor and impedes material flow.
For example, pretend customers buy a Vermeer brush chipper an average of every 75 minutes (not the actual number). Vermeer has organized its entire brush chipper “lean model line”—from raw materials to material prep, welding, painting, assembly and decal placement—so that a completed brush chipper is pulled off the end of the line every 75 minutes. At that time, the work at each station then indexes forward.
Further, Vermeer breaks down the work at each station based on content, so that the operator or operators at each station have exactly 75 minutes of work. When necessary, Vermeer establishes subassembly stations. By breaking down the work, Vermeer can offer customers many different options without any disruption to Takt time.
Healthy “Lean” Diet
Using stations and subassembly stations, poka-yoke fixtures, software-based welding systems and paying for 300 auto-darkening welding helmets runs counter-intuitive to many welding operations. In many facilities, a single welder, or perhaps a small team of welders and fitters, builds a product from start to finish. Such shops often and rightfully pride themselves on old-school craftsmanship standards. Unfortunately, they are competing against new-school players who can produce higher quality products at lower cost and deliver them to customers faster with the flexibility for more options.
Lean principles contribute to higher profit margins, happier employees, better quality products, satisfied customers and suppliers— and a more sustainable future. While change is difficult, personally challenging and even painful, it makes everyone stronger. Given the manufacturing challenges of the next decade, more of the U.S. welding industry needs to embrace lean principles and live the language daily.
The seminal book Lean Thinking by Womack and Jones introduced five core concepts:
- Specify value in the eyes of the customer.
- Identify the value stream and eliminate waste.
- Make value flow at the pull of the customer.
- Involve and empower employees.
- Continuously improve in the pursuit of perfection.
5S–the Japanese concept for Housekeeping
- Sort (Seiri). Tidiness, organization. Refers to the practice of sorting through all the tools, materials, etc., in the work area and keeping only essential items. Everything else is stored or discarded. This leads to fewer hazards and less clutter to interfere with productive work.
- Straighten (Seiton). Orderliness. Focuses on the need for an orderly workplace. Tools, equipment and materials must be systematically arranged for the easiest and most efficient access. There must be a place for everything and everything must be in its place.
- Shine (Seiso). Cleanliness. Indicates the need to keep the workplace clean as well as neat. Cleaning in Japanese companies is a daily activity. At the end of each shift, the work area is cleaned up and everything is restored to its place.
- Standardize (Seiketsu). Standards. Allows for control and consistency. Basic housekeeping standards apply everywhere in the facility. Everyone knows exactly what his or her responsibilities are. Housekeeping duties are part of regular work routines.
- Sustain (Shitsuke). Sustaining discipline. Refers to maintaining standards and keeping the facility in safe and efficient order day after day, year after year.
- Safety. Not part of the original 5S definition, but often added. A safe workplace improves morale and lowers health-related costs.
Kaizen (adapted from Wikipedia.org)
Japanese for “change for the better” or “improvement.” The English translation is "continuous improvement."
The goals of kaizen include the elimination of waste (defined as “activities that add cost but do not add value”), just-in-time delivery, production load leveling of amount and types, standardized work, paced moving lines, right-sized equipment, etc.
A closer definition of the Japanese usage of kaizen is “to take apart and put back together in a better way.” What is taken apart is usually a process, system, product or service.
Kaizen is a daily activity whose purpose goes beyond improvement. It is also a process that, when done correctly, humanizes the workplace, eliminates hard work (both mental and physical) and teaches people how to do rapid experiments using the scientific method and how to learn to see and eliminate waste in business processes.
Takt Time (adapted from isixsigma.com)
“Takt” is the German word for the baton that an orchestra conductor uses to regulate the speed, beat or timing at which musicians play. Lean production uses Takt time as the rate or time that a completed product is finished, and it is based on the rate at which customers buy your product. Related to Market Rate of Demand (MRD) and “the pull system.”
Poka-Yoke (adapted from isixsigma.com)
Originally called "fool proofing" and later changed to “mistake proofing” and “fail safe-ing” so employees weren't offended, poka-yoke translates into English as to avoid (yokeru) inadvertent errors (poka). The result is a business that wastes less energy, time and resources doing things wrong in the future.
In Vermeer’s welding operations, this would be where parts only fit into a jig one way: the right way. The company has just embarked on this activity.
Toyota Production System (adapted from Wikipedia.org)
The Toyota Production System (TPS) is the framework and philosophy organizing the manufacturing facilities at Toyota and the interaction of these facilities with the suppliers and customers. Three men largely created it: the founder of Toyota, Sakichi Toyoda, his son, Kiichiro Toyoda, and engineer Taiichi Ohno. The main goal of the TPS is to eliminate waste (“muda” in Japanese). TPS targets seven kinds of waste:
7. Processing itself