Electricity + Control March 2019

PLANT MAINTENANCE, TEST + MEASUREMENT

the traps would have failed. Hence, if there are 60 medium-sized traps on the system, losses from ’blow by’ could be estimated to be between half a million rand and R850 000 per year. Follow-up actions To check steam trap performance, ’sight, sound and temperature’ are the main factors to be con- sidered. Implementing a basic annual inspection of the steam traps and associated equipment using infrared inspections could reduce steam losses by 50% to 75%. Ideally, a steam system manage- ment programme should establish repair priorities based on safety, steam/energy loss, and possible impact on production and quality loss. Whenever a problem is discovered using a thermal imager, the associated software can be used to document the findings in a report, including a thermal image and a digital image of the equipment. This is usually the best way to communicate the problems found and to suggest repairs. It is also helpful to schedule a follow-up inspec- tion on the report form. The follow-up should be scheduled soon after repairs have been done so that performance can be validated.

ensure that all traps are inspected at least annual- ly. Larger or more critical traps should be inspected more frequently, as the potential for loss is great- er. Over time, this process will help determine whether a hot or relatively cool spot is unusual or not and will help to verify whether or not repairs have been successful. What represents a ’red alert’? Water boils at 100°C to make steam, which is routinely transmitted at high pressure; this is ex- tremely hazardous so any condition that poses a safety risk in the system should take the highest repair priority. In many situations, the next most important kinds of problems to deal with are those that can affect production capabilities. What’s the potential cost of failure? The cost to an operation that completely loses its steam system varies from industry to industry. The chemicals, food and beverage processing, and pharmaceuticals industries are among those that use the most steam. If no maintenance of steam traps has been performed in a facility for three to five years, it may be expected that 15 to 30% of

Comtest supplies Fluke thermal imagers for inspecting steam systems.

Infrared thermography is one of the key condition-monitoring technologies to use in monitoring and maintaining steam systems at optimum performance levels.

Electricity + Control

MARCH 2019

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