"Value added" is an oft-used term, but for today's suppliers of stamped parts, the actual stamping work is just one part of the supplier sourcing criteria. Offering core capabilities such as design and engineering, a stamping provider should be a manufacturing partner.
The number-one expectation of a metal stamping supplier is that they add value to a project. With continued global pressure on pricing and profit margins, it is vital to procure a supplier that will not just make a part but adds value to the project. This value includes work and capabilities beyond the stamping process.
As the actual stamping work is only one part of a project, it is important to select a reliable and financially stable supplier -- a supplier that can do most of the work in-house and finish deliverables within scheduled deadlines. By asking the right questions and doing basic investigations, a manufacturer can ensure that it does not select an underperforming supplier. Substandard metal stamping leads to costly malfunctions and product delays, harming the manufacturer's reputation.
Look for Advanced Stamping Capabilities
Does the shop have the required stamping capabilities? Manufacturers might not immediately know the best process for a project. A shop with many in-house capabilities can alter the stamping process with the least disruptions. A stamping company should not be a "one-horse" shop; it should have access to processes like bending, forming, blanking, coining, and piercing (among others).
When a company has in-house experience with these processes, it will have the knowledge to choose the process to create the best part for its customer based on the requirements.
If deep-draw metal processing is required, working with a specialist, not a "generalist," is necessary for precision parts.
If deep drawing is required for a project, it is important to find a specialist in this process and not just a shop that does deep drawing as well as other work. Deep drawing is a very complicated manufacturing process, so having a specialist is almost a requirement, and that will be reflected by the quality of the product.
Know the Difference: Parts Provider vs. Solutions Provider
Working with a firm that is a partner and not simply a supplier has great benefits. When sourcing a stamping supplier, look for one that will work with you on design changes and process decisions.
In addition to functioning as a "one-stop shop" for a project, the stamping supplier should have the engineering capabilities to meet the quality standards required for each of these processes. It should not have just enough capability to get by. Finding a supplier that becomes a manufacturing partner will reduce product development time and costs.
The supplier's technical team should participate in collaborative meetings, helping to evaluate the design of the part. These meetings should be open discussions concerning component design and manufacturing processes. In this way, any deficiency of the supplier -- or the manufacturer -- can be addressed openly and resolved above board and before it become costly.
Vet the Quality Management Systems
What quality management system (QMS) procedures should the manufacturer expect from the stamping supplier? A QMS is a collection of business processes that allows the firm to achieve quality policies and objectives. The processes tend to combine sustainability and transparency.
The ISO 9000 family of standards by the International Organization for Standardization is currently the most widely implemented quality-management set. More specific, ISO 19011 deals with quality and sustainability and their integration. Quality certifications from ISO are the primary requirement for quality assurance.
Capabilities Should Go Beyond "Just Stamping"
A quality metal stamping company should provide a variety of secondary operations. In addition, the stamping company should be able to handle specialized operations either in-house or through a network of suppliers. In this way, the product is managed by a single supplier.
Secondary operations that a stamping supplier should handle in-house or through a network are:
- Pre-plating and post-plating processes
- Precious and non-precious metalwork
- Heat treatment
- Tooling and trimming
- Painting and electrocoating (e-coating)
- Forming and welding
- Specialty edge cleaning and deburring
- Passivation and sterilization
- Assembly and packaging
To streamline a project, each stamping operation and secondary process is best assigned to a single technical expert. This expert should see the project through, from start to finish.
How Does the Company Document Quality Control?
In order to ensure that product quality is maintained, it is important to keep a wide range of documented quality control reports. When investigating a company, it is important to know how the company records its quality control and what kind of reports the company maintains. The following are some examples of these reports and their use in recording quality.
A First Article Inspection (FAI) is a measurement of the properties and geometry of a sample part to determine if it meets specifications. Despite the name, the first article is not necessarily the first part off a production line. The FAI is typically called for in contracts between producers and buyers to prove that production produces reliable results.
A histogram is a graphical representation of data distribution. It estimates the probability distribution of a continuous variable, such as a specification or tolerance. It is a measured frequency determined over discrete segments. The area enclosed by the histogram equals the total data points collected. A histogram is one way of determining standard deviations and probabilities for future results of a product.
- Xbar-R Charts
An Xbar-R chart consists of a pair of charts. One chart monitors the standard deviation of the variable, and the other chart monitors the process mean. This chart tracks the mean value
for a quality characteristic with respect to all units in the sample. It is a more in-depth view of the statistics involved in production variables than a basic histogram.
A Production Part Approval Process (PPAP) is used to confirm that suppliers understand the design and specification requirements of a part. It also determines a supplier's capability to deliver a product that complies with all requirements. Critical process elements that it determines are ownership, definition, documentation, established links, analysis and monitors, and maintenance records. A PPAP package is a series of documents formally approved by the supplier and customer.
Other than its capital equipment, what other systems should a manufacturer expect from a metal stamping company?
These days, technological advancements consist of new software and in-process sensing. Product simulation software assists in part design from beginning to end. Three-dimensional simulation software enables near-perfect part design prior to prototyping or production. This software models a new part with different options and can determine manufacturability and reliability.
The latest sensing technologies can monitor quality throughout the stamping process. It tracks total part quality, ensuring it is maintained plant-wide. Video inspection systems are also available to promote consistent production quality. These systems use statistics to analyze any variability in the process. They are able to monitor in real time and spot trends to identify unacceptable variances. It is important to know that a metal stamping supplier is taking advantage of advanced technologies, which drive down costs and increases production efficiency.
Top photo credit: American Industrial Co.
David Dunn is president of American Industrial Co. is a provider of precision metal stamping and assembly services based in Gurnee, Ill. American Industrial Co. offers design and engineering, prototyping, quality, secondary services, and tooling capabilities. The company performs bending/forming, blanking, coining, and piercing on steels, aluminum, brass, and copper. It also provides reverse engineering, heat treatment, part inspection, and part finishing.