Walker Process Equipment: Papers

Papers The following index lists papers written by staff members of Walker Process Equipment. These papers are intended to provide a perspective and insight into the various features of various types of equipment used in the water and wastewater industry.

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To view a list of product literature, click here.

On-Farm Biogas Recovery Systems - Plant Profiles

Drives for Clarifiers

Four Point Contact Slewing Bearing Lubrication & Maintenance
May 2006: This paper compares the maintenance and lubrication recommendations of the slewing ring manufacturers and the maintenance and lubrication recommendations of component drive assemblers for slewing rings used in their drives. These recommendations do not agree in many important or critical procedures. References are presented from the manufacturers' literature so that the reader can verify the points at which the manufacturer and the assembler diverge.
Drive Comparison - Walker Process Equipment Replaceable Wire Races vs. Gothic Arch Combination Gear and Bearings
February 2003: This paper provides direct comparisons of clarifier drives that utilize replaceable wire races and those that use the gothic arch combination gear and bearings. Within the paper are summaries that compare main bearing design, gear design and quality, housings, corrosion resistance, lubrication, and maintenance.This paper examines issues concerning the lubrication of clarifier drives.
Walker Process Turntable Bearing Is Not Just Another Lazy Susan
March 2002: This paper examines the basis for the design of the main bearing in spur gears manufactured by Walker Process Equipment. Some of the topics examined are: loading conditions, configuration, materials, rating methods, lubrication and size.
A Brief History of the Walker Process Equipment Spur Gear Drive
June 2002: This paper examines the history of some of the unique design features built into the Walker Process spur gear drive. Some of the topics examined are: pressure angle, aspect ratio, the split spur gear ring, use of cast iron housings, compliance with ANSI/AGMA and the features of the main bearing.
Lubrication of Clarifier Drives - Why Oil Is Preferred Over Grease
July 2001: This paper examines issues concerning the lubrication of clarifier drives, why oil should be preferred over grease, how the type of lubricant affects maintenance, removal of condensate and other contaminants and the life of the gearing and bearings.
Comparison of Clarifier Drives
March 2000: This paper examines the comparative Precision, Metallurgy and Material Rating of gearing offered by Walker Process Equipment and other manufacturers in the water and wastewater industry. Also discusses, with examples, the corrosion resistance of steel, ASTM A536 Gr. 80-60-03 and ASTM A536 Gr.120-90-02.
The Drive for Today - and Many Tomorrows
Revised April 2008: This paper describes the anthology of the various gear rating criteria which have traditionally been used in our industry, including several revisions to AGMA and ANSI/AGMA standards, and how Walker Process has reacted to fulfillment of total conformance with the latest versions, ANSI/AGMA 2001 (Spur Gears) and 6034 (Worm Gears). This upgrade of materials, quality and production machinery has enabled Walker Process to claim the superior split ductile iron ANSI/AGMA Class Q6 precision gear with replaceable races offered in this industry. Also included is a comparative chart of the features offered by various manufacturers.

Anaerobic Digestion

Anaerobic Digester Heating
Revised in August 2006: This paper describes the basic features of heat exchangers, boilers and burners used in heating equipment for anaerobic digesters.
Digester Mixing Systems - "Can You Properly Mix With Too Little Power?"
October 1999: This paper references various sources, which describe the power necessary to properly mix an anaerobic digester, and compares these values with the Walker Process method of proper selection of a GasLifter. You can mix a digester with lesser values of power consumption, but do you properly mix it?
The GasLifter - A Time Honored, Proven Anaerobic Digester Mixing System
September 2001: This paper describes the GasLifter, an anaerobic digester mixer of the Confined, Recirculation type, used successfully by Walker Process Equipment for over 40 years. Describes its advantages, and compares those advantages against competitive digester mixers of the same type, as well as Unconfined Gas Injection, Mechanical Impellers and Mechanical Pump types. Discloses independent reports regarding various types of digester mixers.
Technical Memorandum No. 1.0 - "The Use of Purlins in Digester Cover Design"
August 2003: This paper discusses the use of purlins in steel digester cover design.
Technical Memorandum No. 2.1 - "Framework and Plates versus Membrane"
Revised in October 2011: This paper discusses the various aspects of truss and membrane design as applied to steel digester covers.

Solids Contact Clarifiers

The MC ClariFlow - The Ultimate Upflow Solids Contact Clarifier
December 1999: This paper describes the newest version of the family of ClariFlow upflow solids contact clarifiers, citing the advanced features which are embodied into the design, why they are a true advancement, and also provides recent installations in varying processes, with contact references.

Grit Removal

Rolling Grit - Product User Testimonial
January 2000: This paper provides a description and testimonial of a Rolling Grit installation at the Fox Metro Water Reclamation District serving Aurora, IL and four surrounding communities.

Product Literature

Headworks

Grit Removal: Rolling Grit Brochure

Biological Treatment

Clarification

Digestion

Grease & Skimmings Removal

Water Treatment