Your Reliability Engineering Professional Development Site
A listing in reverse chronological order of these article series:
A gearbox is used to control the operating speed of industrial equipment.
It converts a high input speed to a lower output speed and so permits one driver element, such as an electric motor, to do numerous duties.
Failure of the gearbox causes the equipment and associated plant to stop.
Proper selection, care, and maintenance of gearboxes is critical to your company’s continued profitability. [Read more…]
Our simple 3 legged stool model from part 1 will deliver high performance at low cost and risk – i.e.: high productivity. It is important however to keep the legs intact! Doing so requires a bit of investment. In thermodynamic terms we need to put some energy into the system to keep the entropy from growing. That energy is investment in maintenance and the payoff comes in the form of steady, predictable revenues with a high margin for profit. Those words should be music to accountants’ ears. [Read more…]
Chemical corrosion occurs at increased rates in agitated conditions.
Typical iso-corrosion curves for alloy metals no longer apply. These curves only show corrosion rates at various chemical concentrations and temperatures in stagnant conditions.
A typical curve is shown below. The curves are available from alloy metal suppliers on request.
When metals are selected for agitated corrosive conditions the curves can only be used in a relative sense.
They help grade the metal selection but they cannot provide absolute corrosion rates. [Read more…]
We all want high productivity – maximum output for the least input, the most blast for our buck! We know that high payback will entail a level of risk, but again, we want to minimize our downside risks and maximize the opportunities that may be available to us. We need practical ways to achieve this. Good Capital Asset Management™ will deliver that – how? Well, here’s a simplified scientific explanation of how that works. [Read more…]
A benchmark is the end distance point from the start.
In the world of maintenance, it is the name for the targets that an organization sets for itself in an improvement program.
Benchmarking is often against world-best practice and it is used to provide direction and focus in an organization’s efforts to improve.
When RAV is chosen as the benchmark it means that the annual cost of maintaining the plant will be measured against the value of the plant.
RAV is a percentage of the cost to replace the plant. The lower the RAV the more effective the maintenance effort. [Read more…]
Let me first say that this is not a slam against accountants or the accounting profession. This is intended to help put what they do in perspective and to show the similarity of what they do with what we, as maintainers, do. [Read more…]
Vibration in equipment is the result of unbalanced forces.
Out-of-balance is corrected by adding or removing material so that when the equipment is operating the unbalance is controlled to an acceptable level.
Keywords: spring stiffness, damping, center of rotation, center of mass, natural frequency, isolation mount, counterbalance, out-of-phase. [Read more…]
We know that there are no “quick fixes” or “silver bullet solutions” when it comes to improvements in maintenance management. In my last article I pointed out that many separate conditions and events must come together properly to achieve “schedule success” – i.e.: the high level of compliance to a schedule of planned work as produced by your planners. That list of includes: [Read more…]
Coatings provide industry with low-cost solutions to difficult chemical corrosion problems.
This article covers the use of rubber, fiberglass, and epoxy linings.
Keywords: rubber lining, resin, composite glass fibers, overlap joints, adhesive, primer, corrosion barrier, repair. [Read more…]
Reliability Centered Maintenance (RCM) is extremely useful for organizations considering certification in Asset Management or looking at improving their asset care practices.
Exploring RCM as a tool, getting training for instance, is something that any organization interested in Capital Asset Management™, Asset Management or compliance to ISO 55001, really should do. Here’s why… [Read more…]
Bridging is the name given to the self- created arch that develops just above the outlet of a bulk material silo or hopper as it empties.
A bridge forms when wall friction holds up the ends of the arch.
To overcome bridging the wall friction must be reduced or prevented from occurring. [Read more…]
Welcome to the final blog in my 10-part series called “Uptime Insights”, where we explore a journey of excellence in maintenance. To stay on top, managers must implement strategies that keep operations performing at high levels. In these articles I will show you how to achieve excellence in maintenance – a critical business process in any capital intensive industry. [Read more…]
Control valves regulate the flow of a liquid or gas by opening or closing internal passages.
They form part of a control loop used to control a process. The control valves respond to instructions from the controller and adjust the internal openings accordingly.
Keywords: sensor, setpoint, trim, actuator, sealing class, tuning, proportional, integral, derivative. [Read more…]
Welcome to part nine of my 10-part series of blogs called “Uptime Insights”, where we explore a journey of excellence in maintenance. To stay on top, managers must implement strategies that keep operations performing at high levels. In these articles I will show you how to achieve excellence in maintenance – a critical business process in any capital intensive industry. [Read more…]
Net positive suction head losses (or why you can suck through a straw).
Pumps cavitate and run dry when the pressure leading into them falls below the vapor pressure of what they are pumping. At vapor pressure, the liquid boils into a vapor and fills the pipe.
In order to know that the pressure to a pump is always above the vapor pressure, it is necessary to calculate that the pressure losses from pipe friction and suction lift will not cause the pressure to drop under the vapor pressure.
The presence of dissolved gas in the liquid complicates the problem. [Read more…]
