Chemical and Materials Engineering Professionals
Design and prepare specifications for chemical process systems and the construction and operation of commercial-scale chemical plants, supervise industrial processing and fabrication of products undergoing physical and chemical change, develop and provide advice on processes used to extract metals from their ores, investigate the properties of metals, ceramics, polymers and other materials, and assess and develop their engineering and commercial applications.
A batch that is not quite right
You are a process engineer at a plant that makes cleaning products, and this morning a batch has just failed its quality check. It is 7am, an order for a big customer is due on a truck at noon, and the batch in the tank has been flagged by the lab. You have a few hours to work out what to do.
Choose what you would do. Then see what happens. There are often good reasons for each choice.
The batch is slightly outside the specification on the thickness test. It is not far out, but it is out. The customer is a big one and the truck is waiting. What do you want me to do with the result?
Ask Lucy to record it accurately and to hold the batch until you know why
Lucy records the result and the batch is held. You can now investigate properly, and the customer will hear from you before they hear from the truck. A failed result is information you can use.
Ask Lucy to retest it and use the better result
The second test passes, but it was a different sample from the top of the tank. The result looks good on paper, and you have no idea whether the whole batch really meets the specification.
Release it, since the difference is small and the customer probably will not notice
The batch ships and the customer reports it later because it does not behave as expected in their machines. A small difference to you is not always small to the person using it.
I noticed the heater cycled differently overnight. It felt off, but I did not think to write it up. I am not sure it matters. Is that any use to you?
Thank him, ask for details and check the log and equipment before you decide it is nothing
Reggie feels valued and you find a sensor drifting a little. It was the cause, but you spent a while checking other things first. His observation was the best clue you had.
Tell him you will look at the process data first and speak to him afterwards
You look at the data and miss the pattern, because the sensor reading looked normal. Reggie decides his observations are not worth sharing next time.
Sit with Reggie for a few minutes, write down what he saw and when, then match it to the data
His timing matches a change in the data, and the pieces fit together. Operators spend whole shifts beside the equipment, and their observations are often the first sign of a problem.
The customer rings every day for updates. If I tell them the batch has failed, they may move their business. Can we say there was a transport issue, and sort it out quietly?
Agree to the transport story to protect the relationship with the customer and sort the real problem out quietly
The story holds for a week, then falls apart when the customer asks the carrier. They lose trust in the company, and the truth would have cost less.
Say the customer should hear the truth, and offer to help write a clear update with a new date
The customer is disappointed but respects the honest message and the new date. A frank update shows the plant takes quality seriously.
Stay out of it and tell Dolores that customer messages are not an engineer's job to write
Dolores writes something vague, and the customer still feels uninformed. Your knowledge of what went wrong was exactly what she needed to say something useful.
How it went
The batch is held, the sensor is found, and the customer knows a new delivery date. Chemical and materials engineering is careful, detailed work, where an honest result matters more than a convenient one. Would you like working out why something did not behave as expected?
This is a simplified, fictional situation to help you explore. It is not professional instruction or a test of your ability.
Case study: The chains on the playground swings
A fictional case set in a plant that makes cleaning and industrial products, plus a lab that tests materials.
The situation
A council in the coastal town of Marlow asked Ayesha, a materials engineer at a testing laboratory, to look at some playground equipment. Two swing sets near the beach had rusted much sooner than expected, and the council had paid for them recently. Nobody had been hurt. The supplier said it was just salty air and that the swings were fine. The council wanted a clear answer before the school holidays, when the playground would be busy.
What they did
Ayesha took samples from the chains, shackles and bolts, and examined them under the microscope. She found that the chain was a good grade, but a cheaper bolt of a different metal touched it, and the two were corroding each other in the damp salty air. She wrote a plain report with photographs showing where the damage began. She recommended replacing the fittings with a matching material and keeping the swings closed until that was done.
How it turned out
The council closed the swings, the supplier replaced the fittings at their own cost, and the playground reopened in time for the holidays. Ayesha has said the real answer was found in a thing nobody had thought to look at first, which was the bolt.
What would you do?
- What would you do if a supplier told you not to worry but your tests said otherwise?
- Why might two metals that are fine on their own cause trouble together?
- How would you explain a technical finding to a council that wants good news?