August 2025 Volume 7

MAINTENANCE

MAINTAINING YOUR UPSETTER FORGING MACHINE By Jeff Fredline

U psetters have been used in the steel forging industry for many years. They are massive machines, many of which are still in service today. Below is a diagram of a Ajax Upset Forging Machine.

Toggle Slide Assembly Running parallel with the Header Slide is the Toggle Slide. The Toggle Slide is also designed to run on the centerline of the toggle pocket in the Upsetter frame. As the pocket and the toggle slide wear surfaces wear the frame wear plates are removed and ground for minimum clean up. Usually, these plates are steel wear plates and are nitrided to increase the wear properties. When the plates are reinstalled measures are taken on the toggle slide and pocket and the plates are shimmed to allow for the proper running clearance and centerline of the toggle slide in the pocket. The toggle slide is driven with hardened rollers running against the cam located on the crankshaft for both the forward and return functions. The purpose of the toggle slide is to move the grip slide into the holding position to grip the steel bar during the forging process. Toggle Linkage and The Grip Slide Two of the most common areas of wear on the Upsetter are the Toggle Linkage and the Die Pocket. Half of the die pocket is located on the surface of the grip slide where the die mounts. The other half, located directly across from the grip slide in the Upsetter frame, is typically referred to as the Dead Wall of the Die Pocket. The Toggle Linkage is attached to the end of the toggle slide with linkage and pins with bushings located in the links. There are several links and also a large link attached to the frame of the Upsetter frame called the Toggle in the Bed. The toggle in the bed is a pivoting link that allows for the forces from the crankshaft rotation and the toggle slide movement to pivot the toggle linkage thus moving the grip slide forward to clamp the steel bars during the upset process and then return the grip slide to its open position at the conclusion of each stroke of the machine. The grip slide also has wear plates and surfaces that must be machined to clean up and then installed shimmed back on the centerlines of the pockets within the machine. Not only is the grip slide controlled by the wear plates, but the stroke of the grip slide is also controlled by the condition of all pins and

The above diagram is of an Ajax Upsetter Machine Manufactured by Ajax-Ceco Erie Press company. Used by permission. Sequence of Operation: As the crankshaft rotates in the frame on bronze main bushings it drives two separate sequences. There is a cam on the crankshaft that moves the Toggle Slide forward and reverse within the frame of the press. This Toggle Slide is attached to the grip slide using linkage. The Grip Slide moves at 90 degrees to the Toggle Slide and applies the holding pressure to the steel bars being formed in the press by the header slide. The Header Slide and Connection Assembly The Header Slide must run on the centerline of the pocket to ensure quality throughput. The slide runs against hardened steel wear or bronze plates mounted to the press frame and to the wings on each side of the slide. These wear plates can be machined and shimmed to hold the slide on the centerline of the die pocket. Also critical to the proper function of the machine is the condition of the running surfaces on the connection and the pocket of the header slide. A bronze bushing within the connection runs on the crankshaft diameter and must be round and true to hold the load during the forging process. On the opposite end of the connection is the nose or pocket bushing. If this bushing or nose surface becomes damaged or worn it can allow the header slide to drift during the production cycle. As with any piece of equipment under load lubrication of the bearing and running surfaces is critical to minimize wear and dissipate the excessive heat buildup. Forging, of course, also generates metal contaminants that work against properly lubricated surfaces.

FIA MAGAZINE | AUGUST 2025 22