For the Week 5 Networking PD teachers in Mackay did an industry visit to INDT (Inspection & Non Destructive Testing). INDT Pty Ltd is a privately owned independent third party inspection and testing company that has been servicing the Manufacturing, Sugar and Mining industries since 2004.

We were fortunate that two Technicians, Victor Zhou – Occupation Mechanical Testing Officer – Certified in Metallography and Dale Chambers – Testing Technician and Workshop Manager, gave up their time after working hours to share their knowledge and expertise for an hour.

We had a hands on engaging experience where we observed Bend, Impact, Hardness, Tensile and fault testing of various types of welds from the mining industry.

The bend testing was done with a similar press to those you see in most INTAD workshops. The impact testing was performed with a pendulum action on the testing apparatus. The same sample of mild steel was tested at ambient temperature and at -20 degrees with very different results visually. The -20 degrees sample had a much cleaner break due to being more brittle from the lower temperature.

We then tested the tensile strength of  some 350 grade mild steel plate that, that had a weld in the centre. The mild steel plate was about 40mm x 30mm and 200mm long. The sample failed just above the bottom Jaw of the testing apparatus at 37 tonnes. The sample stretched out by about 20 mm before it failed. The weld held strong and was the only section of the sample not to show any signs of stretching, cracking or distortion.

The hardness testing was done on cross sections of welds by a series of small puncture marks on each sample. Impact readings along with microscopic images are analysed on a monitor to ensure welds are within industry or task specifications. These welds can also be treated with nitric acid on each cross section enabling the technician to visually distinguish between each weld and the parent material.

Some of the fault finding technology used to find cracks in bolts, shafts and axles was also very interesting, however quite simple. With the use of  several aerosol sprays of dye penetrant, magnetism, ultrasonic probes, florescent light, and developer (white powder) for example we were able to locate cracks on three different samples from a bulldozer assembly.

Everyone grabbed a couple of their favorite samples to show our students. All staff found the hour session very engaging and educational and the hospitality of Victor and Dale was outstanding. We gifted them a couple of college water bottles, spoke briefly about industry and we were on our way.

The aspect I would like to improve with future industry visits is patronage from all local Industrial Technology  departments as so much can be gained from them.  A dinner had been planned as a networking opportunity after the visit however that can always happen next year when we see more teachers on board.