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Quality, Cost Savings Are Stamps of Recognition for Connecticut Manufacturer

Company's Engineering Support is Key to Driving Costs out of Critical Projects

By David Gaines
Associate Editor, Design-2-Part Magazine

On any given day at Connecticut Spring and Stamping's 150,000-square-foot manufacturing plant in Farmington, Connecticut, you might see large, high-pressure presses punching out parts with progressive dies. You might also see various spring and fourslide machines cranking out tiny medical catheter springs, parts with complex contours for jet engine blade locks, and firearm latch assemblies. What's very clear amid all this activity is that quality is a big deal at Connecticut Spring and Stamping Company (CSS), which began operations in 1939 and is today a globally active contract manufacturer that produces precision parts and assemblies--many of them used in critical applications--for a variety of high-tech markets worldwide. In 1994, CSS reportedly became the first spring manufacturer in the U.S. to receive ISO certification of its quality management system. Today, the company holds certifications under ISO 9001:2000 and AS 9100: 2004, and is planning to obtain ISO 13485 certification for medical manufacturing.

Connecticut Spring and Stamping (www.ctspring.com) regularly generates challenging, high-tolerance parts and components--primarily springs, wire forms, and metal stampings--for the aerospace, medical, firearms, automotive, and defense industries. By providing design support, engineering assistance, precision manufacturing, high-level quality control, and on-time delivery, CSS appears to have all of the contract manufacturing bases covered. The company handles high volume or short run parts and assemblies, and manufactures all types of springs out of round, square, and flat wire.

"One of the primary reasons companies look to us is because we have a broad expertise across many different product lines, with significant technical support in each area," states Steve Dicke, vice president of sales and marketing at Connecticut Spring and Stamping. "In the spring manufacturing area, we make most every type of spring on the market. We go from very light wire, with diameters ranging from 0.003 inch up through 0.350 inch. In stamping, we go from very thin material, 0.002 inch, up through 1/4 inch, depending on the application. We can manufacture low and high volumes. We also make a variety of fourslide parts, wire forms, and flat stock, which are also a very broad range of products, 0.004 inch up to 0.093 inch."

The manufacturer builds most of its own tooling in-house to support its spring, stamping, and fourslide departments, and all of the design and engineering is handled in Connecticut. "For aerospace, we stamp out a variety of blade locks that lock the turbines in a jet engine; a wire harness bracket for inside the jet engine; and a multitude of other parts," says Dicke. "We make float wires for the automotive industry that go inside the gas tank for the gas gauge. For the defense industry, we provide a frost shield that goes on a laser guidance system for missiles."

Medical Parts Bring Unique Processing Challenges

One of CSS's specialties is medical parts--tight-tolerance metal stampings, wire forms, and coiled springs that are often assembled for general and specialty medical devices, including surgical instruments, monitoring devices, drug delivery systems, endoscopes, laparoscopes, and orthopedic parts. "We make a lot of components for drug delivery devices," says Dicke. "We make drive channels for many of the endoscopic clip appliers, along with the jaws, and some of the staples or clips for the clip appliers; we also stamp a cam bar for a medical device. Many of these parts are components of a medical device, and often, the customer doesn't communicate the exact assembly function of the parts we're producing for them. We continue to get more involved by requesting solid models from the customer; this allows us to evaluate function and suggest possible part improvements to improve functionality or reduce cost." (see Stamping Company Coins Cost-Effective Solutions for Critical Medical Components)

In one instance, CSS was able to achieve cost savings for a medical manufacturer whose part was initially being machined. The company was able to provide its client a complete subassembly that was ready for shipping. "We were producing a single stamped component, and suggested that they consider sintered parts in place of the costly machined parts they were purchasing," says Pete Marut, sales engineer at CSS. "It ended up saving them a lot of money by removing the need to machine the parts. We then assembled the sintered parts with a plastic component to complete the assembly. They were able to drop the finished assembly into their product box when it got to their plant."

In the firearms field, CSS supplies parts--including recoil springs made from stranded or flat wire--for hand guns and automatic weapons. The company can supply trigger bars, ejectors, rails, sight assemblies, complete magazine assemblies, and any other type of spring or stamped component in the weapon. Numerous stamped springs, such as leaf springs, are also manufactured by the firm. "For firearms, we produce special stamped springs," says Marut. "We utilize the fourslide machines to form wire and flat material with minimal material usage."

Highly-Engineered Metals Offer Specific Properties for Critical Parts

Working with exotic metals is another specialty of CSS, which often processes alloys like Hastelloy^®, Waspalloy^™, or Elgiloy^®. "In some ways, it sets us apart from some of the other companies doing the same type of work, but we're not the only company working with these materials," says Dicke. "Some companies work with Inconel^®, but they don't work with Elgiloy or Waspalloy. We often have material challenges with the metal stamping side, with the Elgiloy and Waspalloy, 17-7 stainless steel, and Inconel. We use the Inconel for making aerospace parts, like wire harness clips and blade locks inside the jet engines, because the Inconel is very heat- resistant." Connecticut Spring and Stamping produces many different types of springs and metal stampings daily from flat-stock materials, such as beryllium-copper, chrome-vanadium, chrome-silicon, Hastelloy, Inconel, nickel-silver, Ni-Span^®, phosphor-bronze, stainless steel, and Waspalloy. The company also manufactures a variety of wire forms and springs from wires made out of beryllium-copper, chrome-silicon, Elgiloy, Inconel, Monel^®, nickel, Ni-Span, phosphor-bronze, music wire, resistance wire, shaped wire, spring steel, and stainless steel.  One processing challenge that makes the exotic metals hard to work with is their inherent movement during the heat treating process. "As we're developing the heat treating process, we have to take this movement into consideration," says Marut. "We have to compensate for the movement during heat treating at the design stage of the project."

The manufacturer's engineers have developed proprietary processes for correcting the movement during heat treating. "We make a lot of firearm magazine springs," Dicke explains. "We do the same things when we're making springs for the firearms. They will distort during the heat treating process, so we developed a process to basically form them distorted, so when they're heat treated they'll move back into specification."

Another dicey situation occurs when working with stranded wire materials in the spring-making department. "We use high-carbon steel, 'stranded wire' for some of the recoil springs," says Dale Pereira, the company's spring estimating engineer. "It's all odd numbers--three, five, and seven strands. We only use it to make compression springs. Basically, it's wound on itself and is very difficult material to form. We buy it already stranded from a specialty materials supplier. It tends to come unwound, so we've come up with ways to deal with that. And it doesn't help when you try to wind it. It's not a standard, round cross section of material."

The company is able to support its OEM customers--including many Fortune 500 corporations--all over the globe with a formal network of primarily Chinese and Mexican parts suppliers and assemblers. In this way, CSS manages all of the complex global logistics and engineering efforts from its plant in Connecticut. "Many times, we'll ship parts from our Chinese manufacturing plants direct to an OEM customer that has a plant in China," Dicke explains. "We also manufacture parts here in Connecticut that go to Mexico for final assembly. This is a supply link that allows our customers to go to the lowest-cost area. We provide all of the technical engineering and quality support here in Farmington as a central control point."

Design Review Teams Keep Supply Chain Running Smoothly

To expedite design and production with outside sources, the company enlists its design review teams to verify that every involved party is marching to the same drummer. "Along with doing all of our design work in-house, we strive to do all of our tooling in-house, but it's impossible to staff for all of the highs and lows of production," says Marut. "So if our tooling capacity is an issue when we receive an order, we have developed a very stringent outsourcing program in the U.S. and Asia. We have several approved vendors where we can outsource our tooling and have it built to our standards to meet our customers' needs. Sometimes the tooling suppliers will also design the tooling, but to our standards."

The company also produces assembly equipment that's designed and built in-house to automate the production of complex subassemblies. One example of the company's assembly offering -- manual and semi-automated -- is a firearm component. "Our firearm magazine assembly is mostly manual, but we've developed some machinery to assemble some subcomponents," says Dicke. "We've done assembly for the major computer companies with automated machinery that we've developed to put stamped springs and components together." One of the company's biggest strengths is the engineering support and technical recommendations that it can offer on design issues for a broad range of springs and stampings. "If we see a feature in the part that is not manufacturable, or that might cause headaches down the road, we try to suggest different options," Marut affirms. "It could be a material callout, a heat treat specification, or a change in the design."

Cost-driven features of a part are addressed early on in the project and eliminating added processes and features is an efficient method of excluding additional costs. "There are certain capabilities that a progressive tool is capable of producing within the tool," Dicke reveals. "Sometimes, there is a particular feature that a customer is looking for that can't be done with the tooling, but would have to be done with a secondary operation. These are the things that really drive cost into a part."

On-site Machining Adds Needed Features to Stamped Parts

Besides handling assembly on-site, CSS can machine features into a stamped part. "We do handle a little bit of machining in-house, but we don't do any bar stock machining," Dicke points out. "We have a very specific expertise that we use the machining for. We'll stamp a part and then sometimes machine in certain critical features. A customer may have a fully-machined part that we can redesign for them into a stamped part, with machined features. This can dramatically lower the cost of the part or component."

On the metal forming side of the operation, CSS often provides prototypes--from one to a couple thousand--for various markets. Rather than using rapid prototyping houses to construct a prototype, the company creates them on-site using a variety of different production methods, depending on the form, fit, and function of the part.

"We use wire EDM, laser-cut, or photo-etched blanks with secondary forms," says Marut. "Our lead time on any of them is from one week to four weeks, but our standard turnaround goal is two weeks for most prototypes. Turnaround times depend on material availability, part complexity, and the time involved if heat treating is necessary."

Waspalloy^™ is a trademark of Haynes International.

Inconel^® is a registered trademark of Special Metals Corp.

Monel^® is a registered trademark of Special Metals Corp.

Hastelloy^® is a registered trademark of Haynes International.

Ni-Span^® is a registered trademark of Special Metals Corp.

Elgiloy^® is a registered trademark of Elgiloy^® Limited Partnership.