I've traveled the world since the early 1980s training plant operators and repairing asphalt plants. The question I hear most: "What kind of person makes a good plant operator?"
It always amuses me how much weight management assigns to computer skills. With today’s computerized control systems, almost all operations are "menu driven." If a person can operate a mouse, the computer operations are relatively simple. I assign a much higher value to mechanical skills. After all, if the plant is broken down, what good is the computer?
I recommend finding a reasonably intelligent person with a mechanical background. A person from the company's shop is a good choice. These people normally have an interest in mechanical things and are less likely to be intimidated by the noisy environment of an asphalt plant.
If at all possible, the candidate should first be assigned to the asphalt plant as ground-man. Care should be taken at this time to completely answer every question the person asks. The answers these people receive at this point in their training bear heavily on their success later on.
Hands-on experience important
The most important thing is to teach a prospective operator is the repair and maintenance phase. Anyone can pick-up the fundamentals of the control room in relatively short order, it's simply a matter of pressing the right buttons in the correct sequence, given a certain set of circumstances. What separates exceptional asphalt plant operators from the rest is the ability to address problems before they mushroom into a crisis that causes major downtime. To do that an operator must be intimately familiar with the machine to be operated. Familiarity only comes from hands-on experience.
As with any training program, success is directly proportional to the amount of time the trainee spends in that environment. I've encountered situations where companies have streamlined this 'outside' phase of the operator's training. Gaps in training, however, could surface in costly manifestations of shattered parts which cost money to repair. More importantly, a plant fails to make money while it's idle.
Once the trainee begins to demonstrate an understanding of the hot mix process and the function of the different plant components, it’s time to move them into the control-room for short stints in the driver's seat. During this time it's essential to cement in the trainee's mind the fact that if things don't work outside, there's no need for anyone to occupy the operator's chair in the air-conditioned comfort of the control room.
I also find it advantageous to insulate the trainee from the worry of mix designs or specifications at this time. Most companies have a member of management whose attention is firmly focused on these issues and would be able to guide the trainee through any adjustments needed.
As the trainee becomes more familiar with the day-to-day plant operations and begins to feel comfortable at the controls I find it helpful to send them out with the paving crew for a few days. This gives them a sense of purpose for what they are learning. It also allows them to see what their product is used for and the reasons why the paving crew sometimes call for hotter/cooler temperatures or courser/finer mixes under certain conditions. The best plant operators have a certain amount of empathy for the crews who are using their mix. Remember, experience is an unparalleled instructor.
Learning the nuance of troubleshooting
The skill that will take the most effort to acquire is the ability to troubleshoot the plant. Most times mechanical problems are self explanatory. It's not hard to see why the dryer won't turn when the drive belts are lying on the ground under the gearbox.
Electronic troubleshooting is different story. Repair companies specializing in electronics abound for good reason. In recent years, advances in computerized AC plant controls have simplified plant operations immeasurably. But in doing so those systems have become so complicated that only the most experienced plant operators have the exposure needed to demonstrate any kind of diagnostic skills in contemporary electronics.
It must be remembered that an AC plant is a complex facility, which is probably why not everyone can operate one. To train a good plant operator requires consummate patience and a willingness to risk a certain amount of money. Very few plant operators can say that, early in their career, they didn't make mistakes which resulted in wasted time and product. This is to be expected. But the more thorough a person's primary training, the less likely it is the person will experience a catastrophic problem of their own making.