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Weld Area Organization

Vermeer’s welding areas look and function radically different now than they did just two years ago. Outside of every area manager’s office is a “Welding SQDCM Board” which tracks the five areas that encompass Vermeer’s definition of lean: Safety, Quality, Delivery, Cost and Morale.

In the welding area, the place for each piece of equipment is clearly labeled and marked. There is a place for everything and everything in its place. The weld area contains only the tools and equipment that operator uses; nothing more, nothing less. Rather than strictly using a fixed-height table, weld tables have a scissors mechanism that presents the work to the operator at the appropriate height. This reduces operator stress, which in turn improves weld quality.

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, enabling the operator to orient the part for welding in the best position. The gearbox eliminates the need to use a chain and hoist to flip the component, which in turns eliminates the source of potential hazards.

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 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 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. On one particular heavy equipment line, this lean technique and others reduced lead time from nine to five days ¾ all while incorporating the ability to simultaneously build different models with different options, including paint color.

Takt-ful Approach

"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 amount of time it takes to produce a completed product. It is based on the average rate at which customers buy that product. Thus, Vermeer builds is products at its Market Rate of Demand (MRD, commonly called “the pull system”). If a facility has “leftover time,” it then uses that free time to work on product or process improvements.

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, imagine that customers buy a Vermeer brush chipper an average of every 75 minutes (not the actual number). Vermeer has organized its brush chipper “model line”¾ from raw materials to material prep, welding, painting, assembly and decal placement ¾ 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 work, Vermeer can offer customers many different options without any distribution to Takt time.

Healthy Diet

Using stations and subassembly stations, poka-yoke fixtures, software-based welding systems and then paying for 300 auto-darkening welding helmets to be used by the operators 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 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.

No welding organization or person should be afraid to embrace lean welding principles. As noted, lean principles contribute to higher profit margins, happier employees, better quality products, satisfied customers, 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 welding industry needs to embrace lean principles and live the language daily.

Randy Broadwater is product marketing manager for Miller Electric Mfg. Co. and David Landon is manager, weld engineering, Vermeer Mfg. Co.