While we spend a lot of focus on conveyor scales and checkweighers, they aren’t the only in-motion scale variants that we work with. The flow scale is a specific type of conveyor scale that comes in very useful when you aren’t really looking for individual weights as much as accumulated weights.
The design of a flow scale is very similar to any other conveyor scale, but it handles the weighing process and the data that it processes quite differently. With a conveyor scale, the normal way of operating requires that only one product passes over the scale at a time. The scale takes a number of weight readings as the product passes over it, and that allows the system to come up with an accurate weight average to assign to that product.
On the other hand, flow scales are perfect for a plant that doesn’t need the weight of every product but still wants to know their daily totals. There are many industries, such as particle or aggregate product type, where this could specifically come in handy.
When working with bulk product where weighing each individual piece is a useless endeavor, a flow scale is a great fit. Things like bacon bits or anything that comes in small chunks or pieces can’t be weighed on an individual basis because that would take a ridiculous amount of time and there wouldn’t be any gain out of it.
The flow scale works by taking weight readings every time a whole scale length has passed. This means that the scale weighs a scale’s length in product for every reading before allowing a new scale’s length in product to take its place. Summing all of these readings up gives you a total weight of the throughput for a given period of time.
Having these weight totals helps a plant to understand its throughput which can in turn help management to know how efficiently their processes are working. With small product, there are many steps where you can lose product, so this data can aid in the analysis of those points of loss.
Having data is important in any business, so if you deal with bulk product, this might be a good solution if you don’t have the information you are looking for.
See our Flow Scale Video
Having a flow scale is great for bulk granular product in order to determine an accumulated weight, but certain products can be far more difficult than others. Some have small grains that can get wedged in tiny spaces and some can tend to stick to machinery. This makes any processes more difficult and working with a flow scale is no exception. For this reason, having a flow scale that is rated for washdown is a major advantage.
When looking at how this improves the flow scale process, we have to inspect some specific products. Use bacon bits as an example. When they are fresh in the plant, they can have moisture that leads them to clump and stick to equipment, which makes them tough to handle. With flow scales, they can tend to stick or leave greasy residue on belting which causes problems.
A flow scale takes repeated weighments while it is weighing to get the sum of the product that is passing over it. The problem with sticky product is that it will add extra weight to the scale conveyor. The little bit of extra weight would seem insignificant by itself, but you have to realize that this weight would be added to the sum every time the conveyor takes a new reading. This can add up to some significant inaccuracy over time.
To make the flow scale safe for washdown, we use stainless steel for exposed metal parts. This extends the life of the product by making it sturdy and protected from rust and corrosion. This means that it is also safe from any harsh cleaning chemicals that you might use during your washdown procedures. The structure of the scale is also meant to prevent places for excess water to collect, avoiding possible places for bacterial contamination.
A flow scale is a unique type of conveyor scale in the sense that it doesn’t take individual weights like most other in-motion scales.
It is primarily for measuring bulk product. This could include all sorts of products like powdered substances, bits or chunks of meat, and even things like eggs with a little care taken into account.
So, you might be wondering what the point of it is if it doesn’t take individual weighments.
It is actually a very useful product for determining throughput and general yields because it allows you to amass daily weight totals of all of the product that passes over it.
Knowing your total product throughput in a day is very useful information.
If the scale isn’t reading as much weight as you believe it should, you might need to inspect or alter some part of the production process. This clues you in to potential issues that might be draining productivity before it is too late.
If using a flow scale for this purpose, you have to be careful about its maintenance. Because of the use of certain products with flow scales, they can tend to accumulate weight through residue or other things that stick to the conveyor.
This can be a big issue for a flow scale because it uses continuous weighing. This means that the scale takes a reading for every scale length that the conveyor travels. If there is extra weight sticking to the conveyor, it will be added to the totals over and over again.
The problem can be solved in two ways.
Regular cleaning is the most obvious.
This limits the buildup that can occur on the conveyor belting.
The other way is recalibration.
This is done by leaving space between segments of bulk product where the scale can zero itself.
This takes the added weight out of the equation even though the buildup is still occurring.
Cleaning is still recommended if you use this method.
If you are interested in realizing the benefits of a flow scale, talk to us today.
The ability to measure production for an entire shift without the expense of an operator is within the reach of just about any food plant.
A flow scale is often the right instrument for measuring production because it needs no attendant, yet it can weigh products that comes across it, even when product is presented to the flow scale unevenly.
To understand why a flow scale is a good choice for measuring production, let’s compare a flow scale to two other common methods:
- Tabulating individual weighments of combos
- Using a conveyor scale
The manpower and equipment expense associated with weighing combos is obvious. Forklift operators are skilled workers who command more than minimum wage; forklifts and pallet mules are expensive to own and operate. Any method of measuring production that is labor intensive and requires a forklift is clearly a drain on a company’s bottom line.
Another common method is to use a conveyor scale to weigh products that pass over the scale. Some plant managers find this attractive because it eliminates the expense of an operator and the equipment expense of a forklift. A conveyor scale usually costs a little less than a flow scale.
Problems arise because a conveyor scale works best weighing products that are adequately spaced, or indexed. As chaotically spaced product is presented to a conveyor scale, new weighments need to start before old weighments have been completed. Additionally, products that overlap will appear to a conveyor scale to be one item that weighs double its actual weight. Total weight and average weight figures will be off. It can be tempting to use a conveyor scale to get an approximation of production levels.
For just a little additional investment, no such compromise is necessary.
The genius in our patented flow scale is that it takes one weighment each time the belt travels the length of the scale. That means no indexing is required. Products can be continuously overlapping each other. We need to make sure that the in-feed and out-feed do not interfere with live section of the flow scale. That means sometimes a three-conveyor system is appropriate and sometimes a single conveyor system will do the job.
When you call us to discuss your application, we will recommend the approach that will work best for you!
A flow scale is designed to accumulate weighment data on bulk materials. Although this scale is not NTEP certified, it is a highly accurate conveyor scale with an error rate of one percent or less!
The conveyor flow scale operates continuously as material flows across the conveyor. It simply grabs the weight on the scale at specified points of belt movement. The points are electronically encoded according to each complete revolution of the conveyor belt on the scale itself. The tuning-in of this process with the actual product is what provides the accuracy you are looking for.
The flow scale is customized and manufactured according to the type of product, the flow speed of the product, and of course the environment in which it’s to be utilized. For example, design may be for an area of intense wash down requirements in a food processing facility. Thus, construction would be required to be of USDA-approved materials. Regardless of the area of use, stainless steel is the material of choice for strength and durability.
The outstanding feature of a flow scale is that it weighs inconsistently spaced product. Product could be in a granular form in a constant flow or singular items progressing on the conveyor at a rapid pace, but in chaotic form and space.
Although the flow scale is designed for unattended operation, visual inspection should occur periodically to account for possible product buildup. Even though automatic weight zeroing does occur at consistent intervals, one should always strive to eliminate any possible problem areas affecting weighment.
Flow scales gather weight information as desired over specified time periods. This information can be displayed as necessary, or utilized in a control system.
A conveyor flow scale can be a valuable tool as you strive for efficiency!