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Drilled Core Tubes Integral for Liquid Filtration Systems Produced In High Volume By Marshall Mfg

Minneapolis, Minnesota: Marshall Manufacturing Company (Marshall) utilizes automated manufacturing cells that were designed by Marshall’s in-house engineering team. Each manufacturing cell is capable of machining its own specific range of tube diameters and lengths. Typical core tube materials include ABS, Polysulfone, Noryl, PVC, CPVC and stainless steel. These cells are very efficient and generate cost effective products. Individual cell capacity can be as high as 650,000 pieces annually.

Marshall has been machining "Core Tubes" for the filtration and the reverse osmosis (RO) industries for over 30 years. Core tubes are designed by their customers for use in a variety of industries and applications including; water purification, petroleum grading, removing alcohol from beverages, separating water from fruit juices, desalination, etc. Working with many of the Filtration and RO OEM’s from infancy, Marshall continues to provide engineering expertise as well as products built to their customer’s specifications.

The tube cell capabilities include machining both ends of the tubes. Features that can be generated include: turned and/or bored diameters, chamfers, grooves, multiple rows of drilled cross-holes, abraded surfaces, slots and specific overall lengths. Outside diameters range from 0.5" up to 4 inches. Overall lengths are typically held to +/-0.030", but can be held tighter if the application requires it. Tighter tolerances require temperature controlled inspections because the overall length can vary significantly at different temperatures. For example, a 40" long ABS tube will grow .002" per degree of temperature increase. Size, location and geometry of other machined features are held to standard CNC controlled tolerances.

The efficiency of the cells is created by automation specific to the product. Robots and multiple work centers are used with little operator intervention. The key to the cells is the crosshole drilling work center. Marshall’s cells can generate multiple holes simultaneously. A typical core tube may require 160 holes per tube. Marshall has designed tooling, fixturing, and processes that can drill all required cross holes in a few seconds. Marshall’s experience allows them to design drills specific to an application that will generate thousands of burr free holes without drill wear.

Additionally, Marshall Manufacturing is equipped to provide a wide range of complex precision machining services for just-in-time programs in medium to large quantities. They are able to provide their customers parts seven days a week on a KanBan program as needed. Their services include complete CAD/CAM capabilities, CNC Swiss machining, Wire EDM, CNC horizontal and vertical milling, CNC turning, precision small diameter tube and rod bending, multiple spindle hole drilling, polishing, stamping and part finishing.

Incorporating advanced manufacturing techniques such as integrated machine operations, robotics and cell manufacturing, Marshall Manufacturing provides unparalleled quality, value and on-time delivery. Marshall Manufacturing Company is currently certified to ISO 9001:2008 and ISO 13485:2003. Marshall Manufacturing welcomes customers looking for parts and assemblies that may be challenging or out of the ordinary.