How to optimize baking and snack lines
Jan. 3, 2012
by John Gunst, facilities business unit director, and Darryl Wernimont, director of marketing, POWER Engineers
When it comes to assessing their facilities, bakeries and snack manufacturers across the industry share a common interest: How can I best optimize my process and packaging systems? Most start with the larger equipment. Micro and macro ingredient blending, new ovens and fryers, high-speed packaging machines, labelers and case packers — these major components garner the majority of the discussion and focus when evaluating a new or existing line. But what about the glue that holds these pieces together, the transfer and conveyance systems? Frequently overlooked in the planning process, these systems can provide significant opportunities for improved efficiency and increased output.
Typical bakery or snack projects have the following key steps in common:
- A team is assembled
- Key components and manufacturers are identified
- Processes are defined
- Budgets are projected
- Equipment suppliers are pre-qualified (blending system, ovens or fryers, primary and secondary packaging, labelers, and case packers)
- Floor plans and space requirements are established
- Utilities are identified and consolidated for overall loads
- Line automation expectations are established.
With these initiatives in hand, a new project or renovation can be kicked off. Key equipment manufacturers bring their expertise to the job, focusing on the delivery, installation, and operation of their particular piece of equipment. As the project moves forward, the interconnecting conveyors and transfer systems are often assigned to a packaging manufacturer who typically has limited integration experience beyond their core equipment. In the case of used equipment, a local fabrication shop is often selected to manufacture conveyors based on a predetermined floor plan rather than product dynamics and optimal performance.
If your project took a similar path to that described above, you’ve potentially lost a major opportunity to optimize your operation and maximize the efficiency of each piece of equipment. Drawing upon the expertise of an integration specialist skilled in line optimization can increase the efficiency of every piece of equipment in your line.
Transfer and conveyance or baked or sheeted dough products and bar lines; distribution systems to scales; infeed transfers to wrappers, cartoners, or bundlers; and case conveyance to palletizing systems are critical areas that can hamper your plant’s output. Engineering integrators routinely deal with these key areas and can assist you in improving your efficiency.
DISTRIBUTION SYSTEMS TO SCALES.
Though common in facilities processing baked or fried snacks, a distribution system feeding a set of scales is often addressed late in the project and is frequently cobbled together from existing pieces of equipment. Bed depth, conveyor width and speed are all critical factors in optimizing the feed into the scales. Ultimately, scales and baggers should run at the same speed and process the minimum amount of product to empty your process and queue.
The operation of each scale from an uptime and efficiency basis is directly related to the consistency of product feeding into the top of the scale. A consistent flow onto the dispersion cone will enable the scale to best find a “sweet spot” for pan amplitude and duration. This consistent flow can largely be controlled by conveyor width, depth, and speed. As you open the gates to distribute product, you do not want to interrupt the flow of other products downstream. The height of the feed to the scale will also determine the angle, depth, and flow into the weight buckets.
Wrapper infeeds are another area for line optimization that project teams frequently overlook, resulting in a design that is based on available space rather than optimal performance. Wrapper infeeds are a small piece of the manufacturing puzzle that few people specifically, routinely deal with. As such, the impact that they may have on line efficiency is seldom recognized. Getting the product to the wrapper feed is every bit as important as the feed itself.
Even when working with space limitations, you can’t piece a system together and then require the last 20 ft of conveyor to work miracles: It won’t give you the operation you’re looking for. Instead, plan early, challenge the layout of the line, and tune the entire system — from the oven or the sheeter, all the way to the wrapper.
The wide belts that make up the infeed are expensive, but there is a good reason for their design; these belts must be level, flat, square, and maintain a precise speed control. Flat curves spread the product, and often need to run slightly faster. If a belt is out of level, the lines can break rows of sheeted product, reducing efficiency rather than running a complete row. Out-of-square systems can misalign your product, and non-flat conveyors can pre-break rows that you’d like to keep together.
Small errors and design oversights of this nature can be difficult to identify if you are not intimately familiar with this segment of the manufacturing process, and will make your infeed work much harder, costing you operation in maintenance and overall line efficiency.
TRANSFERS AND TRANSITIONS.
A third area of efficiency loss occurs when baked items, such as bread loaves, are turned or pulled out of rows as a result of a poorly designed transfer. As loaves are inconsistent and not always flat, changing speeds between conveyors or using a rail to align the loaves is ineffective. Rather, you must review each conveyor system, evaluating it for:
- Optimal transfers between conveyors
- Appropriateness of guide rails and guide rail positioning
- Properly tied-together conveyors that will not shift or move
- Precise speed controls
- Variable conditions (such as friction) that are difficult to control and subject to change.
In the development of a new line or in the renovation of an existing system, there are always opportunities to increase manufacturing efficiency. Just as you depend upon the manufacturer of your process and packaging equipment for their expertise, you should look to an experienced engineering team for overall line integration and performance optimization. Get engineers on your team early, and you’ll be surprised by how much they can benefit your operation.
This story is sponsored by POWER Engineers, which has one of the most comprehensive teams of engineers and specialists serving the baking and snack industry. As an extension of its clients' engineering teams, the company provides program management, integrated solutions and full facility design for the baking and snack industry. Learn more at www.powereng.com/food.