MPMN: April 1997

Finishing Process Smooths the Way for ISO 9002 Certification

More and more device manufacturers are seeking ISO 9000 certification for their quality systems. Properly implemented, a certified QA system can help reduce scrap, minimize rework, improve overall quality, and give an added marketing edge. Unfortunately, many companies are unaware of the challenges they'll face in achieving ISO certification. The process can take anywhere from six months to more than a year, and it's not unusual for a company to fail its first audit. The complete manufacturing process must be thoroughly examined to ensure that each step contributes to final product quality. Because very few companies have the expertise to evaluate every aspect of their operations, outside professional help is often needed. Paid consultants are one alternative, but as one manufacturer recently came to understand, the valuable technical resources of suppliers should not be overlooked.

The Big Picture

OEC Medical Systems of Warsaw, IN, manufactures digital x-ray imaging systems used in orthopedic, urological, vascular, and neurological fluoroscopic examinations. An increase in global demand, combined with a more general desire to optimize quality control, prompted OEC to pursue ISO 9000 certification.

Naturally, the company wanted it done fast and done right to minimize costs and prevent undue interruptions to factory operations. As Scott Christiansen, an OEC process manufacturing engineer, explains, "You're talking about analyzing every facet of your business that deals with or controls quality. You have to have upper management's cooperation, because you're going to have a pretty heavy initial investment." OEC assembled separate teams to work on different aspects of the ISO standard. Christiansen's team, for example, developed 4 or 5 operating procedures and 10 to 20 work constructions.

The ISO implementation teams soon discovered that some manufacturing processes would be far easier to control and document than others. The equipment housings, for example, incorporate both metal components, manufactured on-site, and plastic components, supplied by subcontractors. To achieve a uniform appearance, the components receive a textured finish prior to assembly.

A Finish to Measure

The finishing process posed a special challenge because it's considered a "special process." As Christiansen explains, a special process generates a part that can't readily be tested to see if it meets specification.

When OEC began seeking ISO certification, quantitative measurements and procedures for routine testing had not yet been developed for the finishing process. And while employees in the coating area were all seasoned professionals, no formal training program on coating formulation, application, or inspection had ever been conducted. Of course, OEC had never received many complaints about coating defects or poor surface appearance, but in order to pass an ISO audit, the company had to show that proper documentation and inspection procedures were in place.

Christiansen decided to seek assistance from an outside coating professional to bring OEC's finishing line up to speed with ISO guidelines. The one person he knew who had both a strong background in coating technology and an intimate familiarity with OEC's finishing needs was his coating representative, Dave Schmidt of Sherwin-Williams.

Finishing First

The first thing Schmidt did was assess all the controllable variables in OEC's finishing line. He and Christiansen reviewed the entire finishing system and discussed ways to enhance control and consistency. In general, the finishing line was operating smoothly--Christiansen and Schmidt just had to figure out how to standardize the inspection process and document each of the steps.

The two men started with the inspection and storage of incoming materials. To ensure that coatings stored past the manufacturer's specified shelf life were not used, all containers arriving at OEC's dock were date coded. In the prep work area, the established procedures for weeding out flawed parts were found to be effective, and needed only minor modification. In addition to visually inspecting all parts, workers in this area were asked to document all defects. Common imperfections encountered, average rework-time required per part, and the number of parts returned were recorded.

Schmidt and Christiansen also initiated better controls at the end of the finishing line. To evaluate finish quality, test specimens were introduced with each new batch of parts that entered the line. A pencil hardness test revealed the durability of the finish and whether it was properly cured. To determine whether a strong bond was formed between the finish and substrate, cross-hatch testing was performed. Failure in either test resulted in the rejection of the finished parts. For documentation of the tests, a storage cabinet was placed in the inspection area. Coated specimens, results from the adhesion and durability tests, records of batch numbers on the coatings used, and information on vapor injection curing settings and the atmospheric conditions were all maintained in the cabinet.

Art School

Satisfied that the necessary controls were in place on the finishing line, Christiansen and Schmidt turned to qualifying the paint crew. Of particular concern was the training that painters received before being assigned to the finishing area. In order to meet ISO guidelines, a program was needed to prove that the painters were qualified to operate the finishing equipment properly.

What they proposed was an instruction course followed by hands-on testing. Schmidt invited his colleague Jim Trawinski to conduct the course. Trawinski was a 26-year coating veteran from Sherwin-Williams with vast experience in employee training. Course topics included characteristics of the cooling system, spray application techniques, troubleshooting methods, and the steps for conducting the pencil hardness and cross-hatch tests. In addition, operation procedures for all the finishing-line equipment were reviewed. Particular emphasis was placed on the VIC unit, which was vital to delivering a superior finish.

Crossing the Finish Line

OEC came through its first audit with flying colors and is now ISO 9002 certified. Christiansen was relieved that the audit went so smoothly. Although the changes made on the finishing line had been prompted by the company's desire for ISO certification, he found that they also had a positive effect on productivity. Plant communications improved, and workers gained a better appreciation of their part in the overall process. Moreover, Christiansen notes, everyone now knows exactly how the quality department goes about approving or rejecting incoming and in-process materials--and that alone can boost quality significantly.

Schmidt recommends that any manufacturer thinking about ISO certification invite a vendor such as Sherwin-Williams to look over its operations and help write some procedures. Chances are, a major overhaul will not be necessary. "We changed nothing about how our painters actually put on the paint," Schmidt notes, "we just defined how they do it. We looked at ways of putting it all together so we get a consistent coating each time."

OEC faced some highly specific challenges, but the methods for overcoming them are well known to all successful companies--planning, teamwork, and knowing where to turn for the best help available.