February 2022 Volume 4

MAINTENANCE

Understanding and Troubleshooting Forging Press Lubrication By Jeff Fredline

As we strive to properly use and maintain forging presses, perhaps the single most important system of the machine is the lubrication system. Proper lubrication is critical and will greatly enhance the overall life of your machine, as well as minimize unscheduled downtime. Through the use of current technology machine monitoring, issues of the past have been eliminated and you can now monitor bearing temperatures, lubricant condition and proper flow without great expense. We will examine both grease and oil lubrication systems and their proper function. The selection of the proper lubricant for the machine is vital to the longevity of your press. Many forging presses use grease as it reduces fire danger and prevents excessive oil on the floor and machine components. Other presses use a combination of grease and oil. • The Central Lubrication System which supplies lubricant to the anti-friction bearings, bronze shaft support bushings, wrist pin, pitman assembly and way surfaces is usually grease. Each of these components should be monitored weekly to ensure that they have proper lubrication to control overheating at the bearing surfaces. • The Bull Gear and Pinion may be grease or open gear lubricant as well as submerged oil if the bull gear and pinion run in an enclosed guard. A weekly check should be performed. All you may need to do is monitor the sight glass in the enclosed guard. Any increase in gear noise should be taken seriously, as there will be a wear condition associated with it. • The Bull Gear or Clutch Bearings usually have additional lubrication points such as grease zerks located in the gear hub, as they cannot be tied directly to the central system as they are rotating components. [I recommend performing monthly checks and adding lubricant per the instructions in the operator’s manual for each machine.] Immediately replace any broken lubrication lines or damaged fittings/zerks. • The Friction Flywheel also has grease fittings as the bronze bushing between the bore of the flywheel and the flywheel hub also requires lubrication. [I recommend performing monthly checks and adding lubricant per the instructions in the operator’s manual for each machine.] Immediately replace any broken lubrication lines or damaged fittings/zerks.

• TheCounterbalance Systemmay have anoil reservoir to feed the ID of the cylinders and keep the piston rings lubricated, if not, oil should be poured in the top of the cylinder, approximately one cup every two weeks. The cylinders will also receive some lubrication through the oil in the air system. The rod bushings will probably have a lubrication line to each bushing tied to the Central Lubrication System. Monitor weekly to ensure that the piston rod does not seem to be dry. If the piston rod becomes scored or worn, the rod seals and bushings will be destroyed. • The Ram Assembly (Pitman, Wrist Pin and Pin/Pocket Bushings, and Upper Knockout) are tied to the Central Lubrication System with a flex line from a frame mounted distribution block and the ram mounted distribution block. Visually check weekly to ensure that the lubrication lines and fittings are intact. Lack of lubrication in this area can become very costly. • The Lower Knockout Assembly may be tied to the centralized lubrication system or have manual grease lines that will need to be lubricated by hand. Monitor weekly to ensure that there are no issues. • The Cams and Brake components that require lubrication will usually also be manual grease lines to be lubricated by hand. Monitor weekly to ensure that there are no issues. • Finally, air-line lubrication is critical, using the proper type and amount of lubricant. Monitor daily as part of your daily maintenance schedule. If the air-line lubricator that supplies lubrication to the clutch seals, you will shortly experience unexpected downtime. Now that we have identified all of the important lubrication points on the machine, we will take a look at the actual lubrication systems. Trabon Style Using Distribution Blocks Trabon, now Graco, is the most widely used system in the press industry. It is important to understand the proper function and how to test and troubleshoot the system. Pumping System Most presses use a barrel pump that pumps lubricant directly from a 35- or 55-gallon steel drum. The pumps are capable of producing a 50- to 75-to-1 ratio to handle the most high-pressure systems.

FIA MAGAZINE | FEBRUARY 2022 20