By Kevin Sekerak, Asst. Mgr. of Spindle Rebuild for Mazak
No manufacturer wants to see part production come to a screeching halt due to a down machine tool spindle, especially if it involves a repair that could have been avoided through proper maintenance. To help keep your operations running smoothly, I offer you these seven simple, yet important, spindle maintenance tips.
#1 – Lubrication is key to a spindle’s performance and longevity. Therefore, it’s important to keep your lubricating fluids clean and at safe operating levels. You should also adhere to the machine tool OEM’s recommended lubrication schedule. If you have an air/oil spindle be sure to service the air-intake filters on a regular basis.
#2 – Check your spindle’s runout every six months and/or after any crash via a ground and calibrated spindle test bar. Also monitor your spindle’s spring force with a draw bar pull force test. Pull force is what secures tool holders in the spindle and a sizable drop in force could lead to vibration and runout, which can damage both your spindle and part.
#3 – Keep a constant watch on spindle vibration levels. If your machine has built-in vibration sensing technology don’t ignore any of the triggered alarms. Worn spindle bearings are usually the cause of increased vibration, so be sure to replace them when necessary.
#4 – Maintain spindle-bearing lubrication. While closed-unit spindles are typically factory lubricated for life, large spindle headstocks, such as those on big turning machines, need to have their bearings lubricated with oil baths. As such, it’s important to maintain the oil levels of these baths.
#5 – If you have a high-speed spindle with a cooling system, always make sure the chiller unit is running properly. A rise in chiller system output temperature usually indicates a spindle problem. If this occurs have a certified technician thoroughly check the system.
#6 – Always re-install any machine covers that have been removed due to routine maintenance or any other reason. These covers protect the spindle area, keeping contaminants from infiltrating the spindle, spindle motor and other components.
#7 – When your spindle requires a repair or rebuild, it’s best to have the machine tool OEM perform the services to ensure the use of factory-certified parts and that all repairs reflect the equipment’s original specifications.
With respect to tip #7, Mazak has an industry leading spindle exchange and rebuild program that’s worth checking out. We offer the option to purchase a new spindle (more than 900 different spindle variations are available), have your spindle repaired (occurs within five days of receipt) or acquire a Mazak rebuilt spindle (over 300 kept in stock).
If you have any questions about these tips or would like more information on ways to avoid or minimize spindle repair costs, please don’t hesitate to contact us.
About the Author
Kevin has been the assistant manager of spindle rebuild at Mazak for three years. He is now responsible for capital investments throughout the Kentucky Mazak production facility. In his spare time, he enjoys playing with his kids and working on muscle cars.