Compressing Lead-Times & Reducing WIP
Rotary screw compressors are designed, manufactured and assembled at Alabama facility
In 1920, George Gille, John Kathe and George Wall presented an improved vacuum pump design to their company’s management. The meeting did not go as expected, and their design failed to spark interest.
Quincy has experienced substantial growth in the screw compressor market over the past several years, but the company knew it had to increase its market share even more to guarantee future growth. As a result, the company concentrated on increasing its manufacturing efficiency and flexibility to meet the demands of today and tomorrow.
Current sales volumes of rotary screw compressors were creating capacity constraints in Quincy’s precision stator machining area in spite of efforts to balance machine loads to exploit capacity. The planned introduction of new air ends further complicated machine loading and required increased flexibility to accommodate new models. This capacity constraint was compromising the company’s ability to respond to increased business opportunities for service air ends, short lead-time orders and new product introductions.
“While contract manufacturing would have eased our capacity constraints, the high costs and risks of having large queues of high-precision components encouraged us to look back in-house,” says David Peed, manufacturing engineer and machining team leader at Quincy. “A more favorable option was to purchase new, more efficient equipment.”
Precision was a serious concern for Quincy. The reliability of the company’s rotary screw compressors is highly dependent on the compressor’s stator and rotors, components that require intricate machining. The machining process of the air compressor housing requires four parallel bores to be machined, two from each side of the cast housing, two of which are approximately 10 inches in diameter and 17 inches deep.
“We’ve found that running deep, wide bores, while keeping the tolerances down to .001 inches True Position in many cases, beats up machine tools pretty fast,” says Peed. “The cutting forces, along with the large amounts of material removed, can wreak havoc on tooling, the spindle itself, the chip conveyors, and countless other features of the machine.”
Because Quincy manufactures a complete product totally in-house, the company is its own machining customer. When machines go down or deadlines are not met, it directly impacts on-time delivery and on-budget performance. This significantly affects the bottom line and could ultimately tarnish Quincy’s image.
“We’re a very efficient company,” adds Peed. “We make the parts, assemble the compressors and get them out the door. We need machines that are as efficient as we are.”
In 1995, Quincy installed a two-machine Makino MC98 cell with 16 pallets. That cell is still running static parts, inlet valves, discharge ends and end caps. Since this wasn’t Quincy’s first experience with Makino, it again turned to Makino for precision and reliability.
Most recently, Quincy installed a Makino Machining Complex (MMC), consisting of two Makino A88 4-axis horizontal machining centers (18,000-rpm spindle speed), and then shortly after upgraded its cell to include an A88E high-speed horizontal machining center (12,000-rpm spindle speed). The complete cell utilizes a 30-pallet flexible manufacturing system to improve the machining of air compressor housings and air inlet castings. An automatic 244-tool changer on each machine accommodates all the necessary tools for common jobs.
Quincy Reduced Cycles Times by 30 Percent
Designed to improve manufacturing efficiency, the MMC2 is an enhanced pallet management system created to meet the increasing and changing demands of customers. The system as-signs work and initiates operations automatically based on machine and material availability, utilizing maximum spindle capabilities and monitoring all automated procedures.
The MMC’s cell controller can handle an unlimited number of parts and can process an unlimited number of steps per part. In addition, it can handle unlimited different parts per pallet and utilizes production order management software that tracks order numbers, part numbers, quantities, dates required and priorities.
This flexibility allows Quincy to produce parts in a just-in-time manner for each order as it moves through production. In order to ensure automated production, Quincy also needed a local partner.
SST Provided a Local Resource
Single Source Technologies (SST) partnered with Makino to help deliver the automated system for Quincy. SST served as a local resource providing engineering services, supplies, application support and customer service. SST ensured Quincy’s Makino cell would be up and running smoothly without any delays in its production operation.
Installation took place in two phases to minimize interruptions to Quincy’s manufacturing operation. Sales volumes were at a record high, and production levels were requiring 24/7 operation. The company had the first two machines and 16 pallets installed and started into production. Makino then set the third machine, laid new rails, moved the load/unload station as well as the cell controller with minimal interruptions to production. Makino worked with the operators to time down periods of the cell vehicle with long run jobs inside the machines. By doing this, Quincy met all of its production demands and on-time deliveries.
Makino Helped Quincy Evolve Its CFM Capabilities
In addition to reducing cycle times, the Makino cell has helped Quincy evolve its Continuous Flow Manufacturing (CFM) capabilities. Since the early 1980s, Quincy has focused on CFM, a manufacturing strategy that produces a part via a just-in-time production approach, at its Bay Minette plant. Since then, Quincy has been improving its build-to-order environment, balancing its production lines to reduce waste and cost while delivering on-time and defect-free parts. The Makino cell allows for continuous production and quick turn-around, allowing parts to pass onto assembly in the same building. The Makinos also allow for repeatable and predictable part manufacturing as orders come in.
“The Makino cell is one of the major advancements in the machining area,” explains Peed. “It has provided us with the ability to increase flexibility and throughput while reducing inventories of both raw and finished goods.”
Expanding throughout the World
Quincy was searching for reliable and precise technology that would help the company increase repeatability and flexibility in its production process. The Makino A88 cell helped Quincy accomplish its goals by delivering an average uptime of 97 percent during production, increased cycle time, capacity and flexibility.
Quincy has come a long way from its cow-milking roots. The company plans to expand its business into China, India, Southeast Asia, Latin America and the Middle East, manufacturing the compressors here in the United States.
“We need to make sure all of our systems will provide the most efficient means of manufacturing our compressors, from start to finish, and allow us to ship the finished, customized product in the time our customers demand,” says Peed. “With our Makino cell, we’re able to accomplish that goal and expand our business.”
Bay Minette, Alabama