Your Reliability Engineering Professional Development Site
The differential pressure transmitter (PT) is used to detect a head of pressure.
The sensing element is connected to the process by pipework and flexes in proportion to the pressure. The resulting distortion produces an electric signal that is amplified and converted to a value on a read-out.
Keywords: pressure sensor, strain gauge, tank level, process pressure, pressure difference. [Read more…]
The first words a maintainer will read when they pick up a work order is the job description. The job description must tell him enough information about the work so he can understand what to do.
Keywords: CMMS, computerized maintenance management system, planning, breakdown repair, corrective. [Read more…]
Vertical tank agitator bearings are required to take both radial and thrust loads.
To protect the gearbox it is common practice to install intermediate bearings on the shaft. If these bearings are exposed to the process vapors then special care is needed to protect them from contamination and ensure adequate lubrication.
Keywords: thrust bearing, bearing stool, roller bearing. [Read more…]
Here are the things to watch out for when you need to fabricate platforms and walkways.
Stairs, walkways, platforms, and ladders are required to be made to the Australian Standard AS 1657-1992. This standard specifies the design requirements and the materials of construction to be used.
Keywords: deflection, allowable load, live load, guard rails, connections, treads. [Read more…]
Written with assistance from Ben Karel of Fusion Engineering Plastics
Pty Ltd. Unit 1, 7 Dobra Rd, Yangebup WA ph (08) 9494 1004
Welding can join thermoplastic parts together. It can be by melting the surfaces and pressing them together or by extrusion welding with a filler rod.
Several methods of welding are available. Proper manual techniques are critical to success as is the pressure testing of pressure parts.
Keywords: electro-fusion, butt welding, electro-socket welding, hot air gun, melt temperature. [Read more…]
Radar level detectors are becoming a popular technique for tank level detection of liquids.
The radar sends a sub-millionth of a second pulse from an emitter and the return signal is detected at a receiver.
The reflection’s time lapse is measured and electronically converted to a distance from the liquid surface. Installation peculiarities need to be understood and appreciated in order to provide a reliable operating set-up.
Keyword: antenna, spurious reflection, reference plane, emission cone. [Read more…]
The work order report is the maintainer’s opportunity to advise the engineer what problems exist with equipment out in the plant.
It can also provide an accurate record of what was found during the repair. This makes it important that work order reports are completed in detail and are reviewed by managers and engineers.
Keywords: CMMS, computerized maintenance management system, breakdown, corrective, work order, implementation. [Read more…]
Book being reviewed is “Maintenance Planning and Scheduling Handbook 3/E
Keywords: maintenance planning, scheduling, planner, performance, productivity, planner. [Read more…]
Polyethylene is one of the most commonly used engineering plastics.
Its chemical resistance properties and ease of fabrication make it popular in the chemical industries. Its molecular structure provides the key to its versatility.
Keywords: HDPE, long chain macromolecule, thermoplastic, plastic welding. [Read more…]
Valves can be used to both isolate and regulate liquid and gas flow.
Valve used for isolation duties must provide secure, tight shut-off. Consideration must be given to the nature of the process chemical, the quality of sealing and the impact of outside environmental occurrences.
Keywords: bubble tight, design pressure, leakage rate, fire rated, differential pressure. [Read more…]
One method to provide a formal means of appraising people’s performance is by using performance reviews. The employee and manager together use a structured check sheet to work through keys duties of the employee.
They address both the good, and not so good, aspects of performance. The end result is an unbiased assessment of the employee’s current performance and a plan to improve it over the coming year.
Keywords: rating scale, verifiable, performance standards. [Read more…]
Chain drives are used when precise speed ratios are required between the driver and driven shafts. A chain drive allows no slippage. An example is on a gearbox driving a conveyor. Chain drives are also used when a large amount of power is required through the drive. For example the drive on large rotating kilns. [Read more…]
Historically numbers have been used to represent the work type.
As numbers are not a universal human method of description, the work type is also described using words.
The proper choice of words is critical if classification errors are to be minimized.
Keywords: CMMS, computerized maintenance system, breakdown, corrective, work order, implementation. [Read more…]
When spares cannot be purchased easily it becomes necessary to manufacture your own.
Local fabricators, foundries and machine shops can often make the item if you provide them with a design and specification.
Keywords: casting, reverse engineering, metallurgy, original equipment manufacturer, second hand. [Read more…]
When equipment breaks unexpectedly it is good practice to investigate why it happened so that the root cause can be rectified and the problem prevented from again happening.
There are no mysterious causes, only poor systems or system failures. It is not often that people intentionally sabotage plant and equipment.
By analyzing why a thing happened the lesson can be absorbed and changes made to business systems to reduce its probability of reoccurrence.
In this article, four equipment failures are reviewed and investigated to determine their cause and the resulting necessary changes.
Keywords: root cause failure analysis, failure mode. [Read more…]