Motion Index Drives, Inc. prides itself on the quality and precision repeatability of its products. Our cam-driven indexers have been in service for over 40 years. Quality, strength and reliability starts with the cams driving our equipment, and we are proud to share the fact that we put extra time into manufacturing our cams and cam followers—countless manufacturers have seen the benefits.
Motion’s barrel and disc cams are cut from high-quality steel by a 4-axis cutter; globoidal cams are cut on a 5-axis. While precision is important in this phase, cams will need to be re-shaped after the flame hardening process. The process can take anywhere from 1 hours (TT075 rotary tables) to 18 hours (RT900).
The temperatures reached in flame induction cause variations to occur in the metal’s surface, requiring an additional milling phase to ensure the cam matches specifications. Nitriding saves time by not altering the metal, making the cam ready for use when complete. Motion’s cams undergo an additional milling phase after hardening, which brings the final shape within an accuracy of 0.005 mm.
Motion utilizes induction flame hardening to harden the steel along the cam follower groove. This process is more costly and time consuming than several alternatives, such as the popular nitriding process, but ultimately creates a higher quality product that resists wear decades after many of our competitors’ cams lose precision.
Hardened (right) and Non-Hardened Steel Cams
The hallmark difference between nitriding and flame induction hardening is the fact that flame induction hardening alters the chemical properties of the steel, whereas nitriding does not. Flame induction applies heat beyond the steel’s upper critical temperature to the surface to be hardened, increasing carbon content (and therefore hardness) on the surface, before being quenched. Nitriding does not require high carbon presence in steel it is applied to. The process does not heat the product to the critical temperature, and alloys a thin layer of nitrogen to the surface.
Nitriding can, in most cases, provide a harder surface that flame induction. HRC values for Nitriding vary widely depending on the quality of steel used, from HRC 52-88; flame induction processes typically remain between HRC 58-62. While nitriding can be applied to a wide variety of steel grades, flame induction requires steel with higher carbon content.
Nitrogen case depths are significantly thinner than flame induction (typically measured between 0.0127-0.6096 mm). Flame hardening, on the other hand, provides layers ranging in thickness from 1.270 to 6.350 mm deep.
Motion Index Drives, Inc. has made a conscious decision to utilize induction flame hardening on its cams and cam followers. The value of a thicker case and higher quality steel can lead to decades more wear resistance than the nitriding process used by many competitors.
Not only do our cams last longer, but in many cases they beat our competitors in price. Visit www.motionindexdrives.com for a look at our products.
