Boiler tube maintenance can be a time-consuming issue for the many industries dependent upon extensive heating and cooling technologies.
Some boilers contain thousands of boiler tube bends that must be separated, inspected and, where necessary, replaced to ensure energy efficiency while preventing downtime in industries as diverse as mining and energy, primary processing and manufacture, oil and gas processing and food, beverage and chemical industries.
One method that has been used to more than halve the time to perform essential boiler maintenance safely is the use of inflatable Pronal flexible lifting cushions from Air Springs Supply Pty Ltd to part the pipes to replace defective components during programmed maintenance to maintain optimum system reliability.
In one major boiler maintenance operation Pronal cushions measuring 1020mmx320m and exerting up to 24 tons of initial force at a maximum of 7 bar were quickly deployed to repair any in-service problems boilers that each incorporated extensive piping with 2000 bends.
During routine maintenance work crews found about 10 per cent of the bends needed replacement, so it became a major undertaking which benefitted greatly from the increased efficiency and safety with the Pronal cushions to replace the previous process in which chains were attached to each side of the boiler pipes, which were braced and pulled apart.
"Our customer encountered a great deal of repetitive setup and actuation work previously,” James Maslin, national sales and marketing manager of Air Springs Supply, said.
"The new method involved simply inserting the Pronal bag in between the bends and inflating them to smoothly open up the gap required.
"Once inflated, maintenance staff inserted padding to secure the gap, for safety, and went about their work. The new operation was completed with more safety and in about 20 per cent of the time required previously."
The flexible lifting bags involved are manufactured by the same company, Pronal, that produced the enormously strong inflatable bags used to lift sections of the liner Titanic from nearly four kilometres deep in the Atlantic.
Their power, safety and reliability are demonstrated by their use internationally in the safety kits of fire and rescue services, according to Maslin.
Manufactured from plastomer and elastomer coated fabrics vulcanised in a vacuum at 140°C, Pronal lifting cushions are designed for loads up to 70 tons to perform mechanical functions such as pushing, pressing, guiding, clamping, blocking, damping, lifting, moving, wedging and materials handling.
The cushions are also easy to integrate into mechanical systems, such as presses, moulds, conveyors, handling robots, lifting tables and other machinery.
In addition to allowing a better job to be done for a safety and efficiency conscious client, the cushions are compact when deflated, for easy transport and storage. Their reduced overall dimensions permit use where a small gap (down to 20mm) is required, while their thrust is evenly distributed over a wide area (vs point loads of alternative systems, for example).
Maslin says the cushions — weighing just a few kilogrammes each — are very easy to adapt to tasks, requiring minimal setup and no costly additional equipment required where standard factory air or mobile compressed air is available. Because they have no sliding seals, they are ideal for high reliability applications in the latest lightweight process lines or for mobile operations in construction, engineering, mining and maintenance.
Maslin says the highly diversified range provides an easily transported and cost-efficient alternative to hydraulic actuation and craneage across a wide range of industries.
Using technology proven worldwide in land and sea operations, Pronal products are available in standard square and rectangular shapes (100 to 1000mm side dimension), one or more stages, and up to 7 bar inflation pressure (12 models). Customised rectangular, tubular or round shapes of diverse sizes are available on order, with multiple accessories available to adapt equipment to different industrial, engineering and physical requirements.