Experienced Design Drives Our Gears
To help our customers better understand some of the complex design considerations we put into planning and manufacturing our Ring Gears, we would like to share a variety of reports, specifications and articles that go into some of the more technical details.
Ring Gear Materials
Historically, ring gears have been manufactured from cast or wrought steel with some limited use of cast iron. With recent developments in structural designs, materials, and process control, a relatively new gear material is now available. Nodular iron, also know as Ductile Iron (DI), or Spheroidal Graphite Iron (SGI), has become an alternative for alloy steel. Although the material properties of nodular iron are approaching those of steel, it is not a fully comparable equal. Therefore, the use of nodular iron as a ring gear material continues to have limited applications. This paper presents a material overview of wrought and cast steel with a comparison to nodular iron. The ring gear materials are evaluated with respect to gear rating standards, mechanical properties, and historical applications. Read more...
Falk™ Alloy Cast Steels
We are our most critical casting user and, therefore, have a sincere understanding of what our customers need. Through years of testing and analysis experience as the leading manufacturer of mechanical power transmission equipment, we have has developed firsthand experience regarding data for tensile strength, yield strength, fatigue strength and hardenability of our alloy steels. Our alloy cast steels have shown meritorious service for heavily loaded gears, coupling hubs and numerous other castings used in the construction, mining, cement, paper and automotive industries. Read more...
Recent Advances in Gear and Pinion Manufacture
Recent manufacturing advances for both girth gears and pinions have significantly increased the power density of gearing used on grinding mills. These advances include new materials which increase the hardness of girth gears, precision machinery to cut large diameter girth gears, carburizing of large diameter pinions, and tooth modifications finish ground into coarse pitch pinions. The combination of these technologies allows girth gearing to now transmit up to 10 megawatts per mesh and wrap around 40 foot diameter mill shells. Read more...
Gear Rating Comparison for Industrial Gear Applications: ISO 6336 vs AGMA 2001
In 1997 the International Standards Organization (ISO) released the long awaited 6336 ISO Calculation of Load Capacity of Spur and Helical Gears. Through the combined efforts of gear technical associations representing countries around the globe, the ISO 6336 gear rating standard has emerged to lead international Gear Manufactures into the new millennium. The load capacity ratings calculated with the ISO 6336 standard are often significantly different than those calculated with the American Gear Manufactures Association (AGMA) standard 2001. In today’s global market Gear Users and OEM’s must, at a minimum, have the knowledge of how each standard compares to the other. Ideally a translation code from one standard to the other would best meet the needs of the Gear User and OEMs for comparing standards. This paper provides the Gear User and OEMs with a technique to make such a comparison. Rating comparisons are performed on actual manufactured industrial gearing utilizing both ISO and AGMA standards, with a side-by-side analysis. Read more...
Gear Rating Impact of AGMA 6014 Gear Ratings for Mill and Kiln Service
The American Gear Manufacturers Association (AGMA) Mill Gearing committee recently released AGMA 6014, a standard for rating gears for grinding mill and kiln service. This paper highlights the information required to design gears to this new method, background of and changes in the new standard, and the cost impact on new installations. Read more...
Mechanical Drive System Uprating
In the never ending quest for increased production, many times the limiting factor is the mechanical drive system for the driven equipment (pumps, grinding mills, conveyors, etc.). Advances in mechanical drive system design, manufacturing and material technologies allow existing equipment to be uprated or replaced with components of significantly higher power density. Read more...
Mill Tooth Form Gearing Specifications
The Falk Corporation used the Mill Type tooth form for gears and pinions from approximately the 1940’s through the 1960’s. To improve the load carrying capacity of Falk gearing, a new tooth form, called Falk Heavy Duty, was introduced in the 1960’s that replaced the Mill Type tooth form. Falk has continued to support the Mill Type tooth form for over 30 years. It has now become necessary to begin limiting the availability of the Mill Type tooth form.
The Falk Corporation strongly recommends replacement gear sets be made using the new Falk Heavy Duty tooth form. This provides two benefits. First, the Falk Heavy Duty tooth form is the current standard for Falk. It is anticipated the Falk Heavy Duty tooth form will be supported for the foreseeable future. Second, the Falk Heavy Duty tooth form has increased load carrying capacity over the Mill Type tooth form. This provides a no-cost performance improvement. Read more...
Gear Teeth Reconditioning Procedure
With information on the actual amount of material an existing gear has between the existing roots and inside rim, along with a template of worn gear teeth, our Application Engineers can make a determination if reconditioning is possible. Read more...
Reverse Engineering Case Study
In some cases, an existing part can be impossible to replace with existing designs. When we have come across cases like this, our design engineers have been able to re-create the original part. In one case, we even worked remotely with a company in Honduras to successfully replace a worn pinion for a cement mill. Read more...
Selecting Inching Drives
The inching drive, also known as a barring or auxiliary drive, is an important component of any mill or kiln installation. It is used for maintenance and inspection purposes, as well as an emergency auxiliary drive to keep kilns rotating when the main motor fails. This paper covers what data the end user needs to provide for proper selection of a drive as well as the different arrangements available to them. Also covered are descriptions of the different components and their associated service factors, as well as safety requirements and issues the end user should be aware of and use. Read more...
Avoiding Bolt Failure Through Advanced Design
To ensure threaded fasteners will bear their load, designers must specify more than just the quantity and size of bolts. This paper looks at why bolts fail and what can be done in the design phase to help avoid bolt failure. Read more...