Properly executed precision maintenance results in improved equipment reliability and considerable cost savings
Precision maintenance is where rubber meets the road in any effort to improve the mechanical reliability of your equipment. The best laid plans, from equipment strategies to detailed job packs, will disappoint if you do not execute with precision. You have to do the right work, right. When it comes to rotating equipment, this means managing the sources of vibration (fasteners, alignment, and balance) and ensuring that the machine’s surfaces are properly lubricated. Put it all together and you are cutting the FLAB: fasteners, lubrication, alignment, and balance. Cutting the FLAB is more than a clever phrase, however. Following this mnemonic results in increased equipment reliability and efficiency that yields quantifiable cost savings to your organization.
By: Drew Troyer & Peter Munson
Precision maintenance in rotating equipment is all about removing parasitic friction from your machines, which significantly reduces wear and improves machine efficiency. Rotating equipment surfaces are separated by a lubricant film that is around 5 microns in thickness – roughly the diameter of a red blood cell. This lubricant film can be overcome by excessive vibrations, lubricant degradation, and lubricant contamination. The result is direct and aggressive contact of machine surfaces, leading to parasitic friction and wear.
The elements of FLAB each work to protect your equipment against these forces:
Fasteners: Properly selected and installed, fasteners hold machines and components in place to avoid unintended movement and vibration This includes threaded fasteners and welded fastening. Additionally, gas, vapor and liquid leaks typically occur at poorly fastened joints.
Lubrication: Proper selection, application, and care of lubricants ensures that the microscopic film between components retains its design strength and keeps them from coming into contact.
Alignment: Precision alignment keeps rotating components operating in their designed planes of motion, preventing excess forces and vibrations that overcome the lubricant film and force components into direct contact.
Balance: Along with alignment, properly balancing rotating components attacks the major root cause of vibration and excess forces. Voltage, current, resistive, and inductive balance is required in three-phase electric motors to avoid excessive degradation of insulation and other electrical system components.
Addressing these issues does not require a major outlay in new equipment, analytics, or operating models. It just requires precise attention to the basics. Furthermore, these basics lie not in business theory, but in the concrete laws of physics. Doing the right things right can yield significant and measurable financial benefits.
- 5 to 15% reduction in repair costs. This is the most direct and immediate benefit to be realized by a focus on precision maintenance. This reduction can be realized fairly quickly and is attributable to reduced wear, more proactive corrective actions, and fewer catastrophic failures. In short, machines that run smoother, cooler, cleaner, and quieter do not chew through components nearly as quickly.
- Roughly 15% savings in asset replacement costs. Most rotating equipment requires replacement well before its designed end of life due to wear. Precision maintenance restores equipment to its designed reliability, recapturing a significant portion of that lost life expectancy. This cuts your operating and capital expenditures for asset replacement – a fixed cost savings.
- 2 to 5% savings in energy costs. Less parasitic friction and cooler operation results in more efficient operations and reduced energy costs. These improvements are directly measurable, as well as being reflected in your monthly energy fixed cost expenditures.
- The improvement in efficiency also yields a 2 to 5% reduction in emissions. Less energy required means less emissions. While not a fixed cost, reduced emissions are an increasingly important goal for many companies.
- Improved equipment reliability can result in up to 5% improvement in production throughput. More efficient equipment and increased operating envelopes can enable additional production throughput – process dependent.
- 20 to 30% defect reduction. Precision maintenance results in less induced defects through invasive work.