Streamlining Wrapper Infeed for Fireworks Packaging

In the U.S. fireworks market, there is no bigger name in sparkler production than Diamond Sparkler Company (Diamond). With an average throughput of 48,000 sparklers of varied sizes and types per day, Diamond Sparkler is the largest manufacturer and distributor of sparklers in the United States. But the company was not always able to handle this volume of product movement efficiently. One packaging function in particular, the end-of-line infeed of boxed sparklers into the wrapper, was a completely manual process that would frequently delay process flow. Diamond Sparkler resolved the problem by putting into place a totally automated infeed conveyor system with continuous-motion accumulation using unique Slip Torque® technology, enabling precision product placement within the wrapper. Effectively, the new infeed equipment has not only significantly reduced labor hours, but has the capability of packaging one million sparklers per day.

Diamond Sparkler
Diamond Sparkler Manufacturing Co., Inc., a division of B. J. Alan Company, Inc., is the only sparkler manufacturing facility remaining within the United States.

Started in 1922 as Acme Sparklers in Chicago, Diamond Sparkler, now located in Youngstown, Ohio manufacturers and distributes its line of sparklers primarily to Phantom Fireworks’ national chain of 60 consumer fireworks stores located throughout 13 states and in Puerto Rico. But the company does market its products to consumers and retailers nationally as well, including catalog sales orders within states where fireworks are legal.

B.J. Alan Company also owns Phantom® Brand Fireworks, Wolf Pack® Brand Fireworks, and The Grucci Fireworks Collection. The company maintains an extensive in-house product testing program that ensures its merchandise meets or exceeds all Consumer Product Safety Commission Requirements.

Diamond Sparkler employs 18 full-time, year-round employees, and up to 40 additional temporary workers during peak production periods.

Sparkler Manufacturing
Sparklers are made from a mixture of aluminum powder, very fine iron filings, barium nitrate, boric acid and dextrin. Iron is used to produce sparks. Heat differences in the metal determine the color of the sparks. Aluminum produces silver and white flames, and sparks. Barium nitrate creates green colors in sparklers and helps to stabilize volatile elements. Dextrin and boric acid function as bonding agents for the mixture.

This mixture is then coated onto blank sparkler poles, ranging in size from 8” to 36”. The sparkler poles are attached to racks which are conveyed through an oven where they are dipped several times into the sparkler mixture, like making candles. It takes about 1 hour and 45 minutes of dipping to produce a finished sparkler.

“Depending on variations in the mixture, we can produce sparklers that crackle, display various colors, or increase and decrease the amount of sparks and smoke,” says John Reiss, Plant Manager at Diamond Sparkler. “Most of our product is produced for use on the Fourth of July, but there is a growing demand for party sparklers on birthdays, anniversaries and weddings where more sparks, less smoke and specific colors are desired.”

The company begins manufacturing and packaging its sparklers in August for the coming Fourth of July, and also purchases sparklers from China, then packages them at its Youngstown facility. By May, the sparklers need to be manufactured, packaged and distributed to retailers.

Packaging Line Bottleneck
After baking the sparklers, they are conveyed to a filler/boxing machine that puts six sparklers into each box, then closes and seals it. These boxes were being packed at a rate of 180 boxes per minute. Diamond would have a worker manually transferring the closed boxes onto a conveyor for input to its shrink wrapping equipment. The boxes needed to be stacked into columns of six or twelve units for wrapping.

Because of throughput volume, the stacked boxes would become easily displaced, inhibit wrapping and slow down or stop the production line. This is where the bottleneck was occurring in the company’s process flow.

Automating the Wrapper Infeed Shuttleworth, Inc. was brought in to engineer a solution that would fully automate the wrapper infeed process. Using an off-the-shelf design that was customized for Diamond Sparkler’s needs, the infeed was set up inline to the filler/boxer machine to (a) receive the boxed sparklers; (b) place the boxes in a uniform position both linearly and height-wise (for 6-pack or 12-pack wrapping); (c) index the packs into the proper space for precise wrapper positioning; and then (d) controlled-release of the packs into the wrapper.

The infeed’s multi-level, continuous-motion accumulation conveyors stack the boxes to a specified stack height (2 high or 4 high) as a set-up for the 6-pack and 12-pack wrapping cycle downstream. The stacked boxes then convey to a fixed stop, and are pushed with a shear-face pusher in a 2 wide x 3 high or 2 wide x 6 high set-up into a Texwrap ( wrapper. The wrapper encloses completely around the packs, which then go into a heat tunnel where they are sealed. Exiting the heat tunnel, they are packed into shipping boxes and ready for shipment. The packs are put into the shipping boxes manually.

The infeed is completely automated and tied in with the other equipment on the line for safety. In the event of a safety activation, the entire line will shut down.

Low Line-Pressure Accumulation
The infeed conveyors are also equipped with Slip-Torque technology by Shuttleworth, which minimizes sparkler damage by creating low back pressure. This low line pressure throughout the continuous-motion accumulation conveyors allows for precise product placement. Should the line need to slow or stop, the conveyors can continue to take production from the upstream line for a period of time instead of stopping. A low-pressure accumulation buffer absorbs irregularities in the production flow, and provides a smooth, even flow on the line.

“Slip-Torque utilizes individually-powered rotating roller shafts and loose-fit rollers, which become the conveyor surface, powered by a continuous chain to control the drive force for the sparkler boxes,” explains Phil Zahm, Project Manger with Shuttleworth.

“The size and weight of the boxes determine the driving force and roller selection. When the boxes stop on the surface of the conveyor, the segmented rollers beneath the boxes also stop, generating low back-pressure accumulation, minimizing product damage.”

Optimizing Efficiency Diamond Sparkler desired to expand its output, while increasing cost-efficiency. With the new infeed system the company has achieved this objective.

“We process close to 50,000 cases through our infeed system seasonally,” continues Reiss. “That is one-gross and two-gross cases of sparklers. Before we were processing 18 cases per hour, now we are handling 22 cases per hour, an 18 percent increase in throughput. Additionally, we eliminated one full-time employee position. It really increased our production, and saved us a good bit of money.”

Reiss continues, “We were also able to complete our production run for our peak season thirty days ahead of schedule.”

About Shuttleworth
Shuttleworth, Inc. designs and manufactures conveyor systems that accumulate, flip, stack, rotate, push, divert and index products between manufacturing processes. For more than 45 years, Shuttleworth has partnered with customers in a variety of industries, designing, building and integrating conveyors to increase productivity, optimize machinery and reduce downtime. It builds system solutions for manufacturers in many industries including electronics, solar, medical, pharmaceutical, food, printing, automotive and health.

For more information on Shuttleworth and its Slip-Torque technology conveying systems visit