Condition monitoring (CM) is not a life-extending activity. Life-extending activities are things such as lubrication, alignment, balancing and operating procedures. It’s very important to keep this very basic fact clear in all communications within your plant; otherwise, too little importance may be placed on the planning and scheduling of corrective work orders originated in CM.
SPM Instrument AB, Sweden, launches a brand new diagnostic method in connection with Leonova™, a hand-held machine condition analyzer. Called the SPM Spectrum™, it is the result of an FFT on the time signal recorded with an SPM shock pulse transducer from a rolling element bearing. The individual bearing frequencies (BPI, BPO, 2*B2 and FT) and their harmonics are highlighted in the spectrum. This is displayed together with the measured shock value and a light signal, green, yellow or red that shows the result of bearing condition evaluation.
Although thermal imagers may be simple to operate, they are most effective in the hands of a qualified technician who understands electrical measurement and the equipment to be inspected. For anyone using this type of imager, the following three points are especially important.
The present study is aimed at establishing the vibration standards for precision machine tools. The machine tools are first segregated and then their vibration data are analyzed for determining the normal vibration level and damage factors (DF). After refining and fixing the vibration standards obtained, they can be used to assess the machinery health.
To be able to truly evaluate the effectiveness of an infrared predictive maintenance program there must be an understanding of the relationship between the equipment that is to be inspected and the problems that are found and repaired. Too often the focus is on only the infrared images that the camera produces while the solutions that the data produced from the program can provide get lost. It all boils down to a simple but fundamental law that is expressed by the equation E = IR8 which focuses on measuring the effectiveness of the overall infrared program as well as on each of the individual components that contribute to its success.
Misalignment is probably the most common cause of machinery malfunction. Considering the importance of alignment, the vibration spectra of alignment is not well documented. Various authors have reported different spectra. The goal of this research was to determine the unique vibration signature for misalignment at varying operating and design conditions such as speed, type and level of misalignment, coupling types and machinery dynamic stiffness.
Why Balance? All rotating components experience significant quality and performance improvements if balanced. Balancing is the process of minimizing vibration, noise and bearing wear of rotating bodies. It is accomplished by reducing the centrifugal forces by aligning the principal inertia axis with the geometric axis of rotation through the adding or removing of material. In order to understand the basics of balancing it is necessary to define the following fundamental terms.
Ultrasonic leak detection has been used for a variety of applications ranging from energy reduction by locating compressed air leaks to quality assurance inspections such as locating wind noise and water leaks in automobiles. The secret to success is to understand the nature of what type of leak produces a detectible ultrasound and what does not, along with the techniques that can be used for effective leak identification.
The purpose of this paper is to introduce condition monitoring and reliability engineers to the principles of using ultrasound for the assessment of machine condition. Ultrasound can be a complimentary technology to vibration, thermography and lubrication monitoring. It must be emphasized that it is rarely successful as a stand alone technology for effective machine condition assessment and subsequent required maintenance planning. This paper concentrates on the use of airborne ultrasound as a complementary technique particularly for machinery that may be inaccessible due to guards or hazardous locations.