Leading finishing equipment manufacturer Guyson International has recently installed a Kerry Pulsatron MKC22 ultrasonic bath for Tam panel cleaning into a precision engineering company which employs rigorous quality control procedures.

When companies, such as aerospace component manufacturers, conduct Non Destructive Testing (NDT) operations using fluorescent penetrant they regularly perform a system performance check using a 'known defect standard'. The aerospace industry commonly use a penetrant system monitor (PMS) which uses a 'Tam' panel test piece, which incorporates 5 star bursts for testing the dye penetrant and NDT process.

Tam panels are made of stainless steel and measure 100mm wide x 150mm long (4" x 6") and have a chrome plated strip covering the length of the panel. The remainder is an evenly grit blasted surface of medium roughness to enable tests for determining penetrant washability. These panels are often used on a daily basis and it is critical that they must be thoroughly cleaned after each test so that subsequent tests are not influenced by residual material from previous usage giving false readings. Previously many of these panels were cleaned using trichloroethylene (trike), some still are, but in these more environmentally enlightened times numerous forward looking companies are making the move to ultrasonic cleaning. Often this is now the recommended cleaning process and is written into many of the specifications.

Ultrasonic cleaning is brought about by the introduction of high-frequency sound waves (usually between 20-80 kHz) into a liquid by transducers attached to the bottom of the tank. The resulting action is called 'cavitation'. Cavitation is created by high and low pressure areas produced in the solution as the sound waves pass through it. In low-pressure areas, microscopic 'bubbles' form. The pressure rises rapidly as the next sound wave passes through the solution, violently imploding the millions of tiny bubbles and creating a highly effective 'scrubbing' action on any immersed component surface. At the standard 38 kHz, this is happening 38,000 times per second thoroughly cleaning penetrant from deep inside tiny crevices.

Guyson's Pulsatron MKC baths can be programmed to maximise the quality and repeatability of results, allowing the user to pre-set exact cleaning times and temperatures, ensuring consistent levels of cleanliness from batch to batch. MKC baths are available in capacities of 6, 14 and 22 litres to suit different workloads.

Operating temperatures from 20 to 80 degrees Centigrade can be set in 1-degree increments, allowing the optimum temperature to be selected for a particular combination of component material, cleaning solution and contaminant.

All functions are controlled by a simple four-button membrane keypad. An LCD panel displays the temperature and time set by the user, the time elapsed since the start of the cleaning process, and the status of the power supply, heater and ultrasonics.

Larger ultrasonic tanks and spray rinse options are also available from Guyson. KS ultrasonic tanks and UCR ultrasonic clean and rinse systems come in a range of sizes: standard KS tanks up to 248 litre capacity, UCR's to 117 litres. Larger sizes are available to special order. Guyson offer a free component trial service with no obligation to buy.