Equipment Toolbox with Keith Grant, February 2013
Many machines have multiple functions, and the goal is to increase production while reducing labor. To keep equipment operating consistently and efficiently, you need a well-established maintenance program, a solid understanding of the operating procedures and a well-trained staff that knows how to safely use each machine.
On-the-job safety is paramount in the bakery, whether you’re operating a bread slicer, divider/rounder, rack oven or even a knife to slice a bagel. Assume nothing when you train someone on bakery equipment. Each employee should understand how the machine operates, how to use it properly, what procedures need to be followed during use and cleaning, and what to do–or not do–during a malfunction. For example, what procedures do they need to follow when taking products out of the oven to avoid burning others who are working in the same area.
You need to evaluate your equipment and recognize if a problem exists that may potentially harm someone. Check if any of the unit’s safety features have been compromised. New equipment has more built-in safety features, but many bakeries still operate machines that are older and may be slightly more dangerous to employees during operation.
Design a training program for each machine that details its designated use, proper operation, lock out procedures and cleaning practices. Review these periodically, and keep watch of employees while using equipment. A properly trained and informed staff will ensure the safe use of the assigned tools and equipment.
Q. I make bread in a small fixed bowl spiral mixer, with a dough capacity of 125 lbs. For the past five years, I have mixed an average of two batches of dough per day using 50 lbs. to 75 lbs. of flour. It seems that the bowl has lowered a few millimeters and there appears to be more space between the bottom of the bowl and the bottom of the mixer hook. Right now, the space between the bowl and hook is about 40 sheets of parchment paper thick and the bowl doesn’t wobble or make unusual noises. The dough is not incorporated completely, with unmixed flour and water left at the bottom of the bowl. What do you think is the problem?
David, via email
A. I checked with the manufacturer of your mixer, and the maximum acceptable distance between the bottom of the hook and the bowl is 1/4 in. Forty sheets of parchment paper is roughly 1/8 in. So it seems the space is within the tolerances of the manufacturer. Since the bowl does not have any wobble or unusual noise, I can rule out worn bearings. I don’t think the machine is malfunctioning, but you will want to check several things to ensure proper function. Your mixer can rotate the bowl in both directions, so make sure the bowl is turning counter clockwise. Try adding some water to the bowl before the flour, or adding the water in two stages as opposed to all at once. While I don’t think your problem is mechanical, you may still want to check the bowl mounts as a last resort. The bowl attaches to the machine through the bowl holder shaft that rests inside the bowl shaft support, which has a sealing ring and two bearings. It is possible the shaft or the bowl holder has worn enough to cause the bowl to sit slightly lower, causing your mixing problems. It also is possible the sealing ring has worn causing the same results. If necessary, the bowl holder shaft can be removed by removing the bolt and lock washer, holding it in place under the belt pulley. This may need to be performed by a certified repair company since the bearings may be pressed on the shaft.
Q. I have a small removable bowl spiral mixer and recently I have had trouble raising the machine to remove the bowl. How can I solve this issue?
Jorge, via email
A. Your mixer uses a motor/belt/pulley system to lower and raise the machine off the bowl. The pulley is attached to a worm gear, which lowers and raises the machine. Two guide bars help keep everything aligned. With the mixer in the up position, remove the side panel to expose the motor and belt. Lock the bowl into the mixer, and lower and raise the machine. Do not put your hands into the motor area during this process; visually watch the belt while it is raising the machine. If the belt is slipping, you need to tighten the tension. To do this, remove the bowl, shut off the service disconnect to the machine and lock the disconnect. Before tightening the belt, check it for wear. If there are any signs of the belt fraying or cracking, replace it with a new belt. Adjust the tension so there is no more than a 1/2 in. of resistance when pushing on the center of the belt. Grease nipples, which are located on the front of the machine behind the bowl mounts, should be lubricated according to the manufacturer’s recommendations. Remove the lock on the disconnect, turn it on, install the bowl and repeat the lowering and raising. You may need to make additional adjustments to smooth out the raising process.
Have questions about how to keep your bakery equipment running efficiently or what type of equipment is best for your operation? Ask Keith Grant, Modern Baking’s Toolbox editor. Send your bakery equipment-related questions to firstname.lastname@example.org. Grant is the production manager for Deising’s Bakery, Kingston, N.Y.