No Two Scales are the Same

Written by Jason Quade, OEM Accounts Manager

If I had a nickel for every time a customer asked for a ballpark price on a 14-head Yamato combination scale or wanted to know if a used 6-liter scale will work instead of the 6-liter scale I quoted them, I wouldn’t be drafting this article. It is true, if you have a few key pieces of information about a scale, you can get a decent idea of its capability and cost. However, it doesn’t tell you the whole story about how that scale will perform in your application, or if it is even the best configuration to provide you with optimum speed and accuracy.

The truth is: No two scales are the same.

Let’s investigate this a bit further.

The basics just get us started.

A customer may call and say they have an existing 5 to 6-liter scale with 14 weigh heads. They ask me for a budgetary price on a new combination scale. I’ve got a few basic questions I’m going to need answers to first:

  • What products are you running?
  • What are your target weights?
  • What speeds do you need to run?

The Yamato Alpha Series scale is an excellent option to run dry, free-flowing products with target weights under 1000g at 50-60 weighments per minute. Your product is IQF? The Alpha scale is a wipe down-rated scale, but you will need a wash down-rated scale. We will have to look at a different series now.

No two scales are the same.

Different products require different scales.

Using an IQF application as our example, I would recommend the Yamato Epsilon or Omega Series. The Epsilon scale is wash down rated and will be a smart choice to run IQF products. What do you think?

But then you inform me that you are running IQF chicken pieces and need a high-sanitation scale. In that case, then your multihead weigher will require continuous welding and no flat surfaces that allow standing water. I would recommend a scale from our Omega Series with all the high-sanitation features for this application.

No two scales are the same.

Found a used combination scale? Proceed with caution.

If you tell me that you found a used Yamato Omega 6-liter scale with 14 heads that is available immediately, I’d be happy to look up the configuration for you. Let’s say I do that, and I tell you that this scale was configured to run salad and leafy greens. It has a steep-angled top cone and tilted linear feed pans to help the large leafy greens move on the top of the scale.

If you were to run IQF chicken on this scale, the product would move so fast down the cone and feed pans it would fly off the top of the scale and never even drop into the scale’s buckets. It would be exceedingly difficult to control the feed into the buckets, making this scale essentially useless for you. Also, our salad scale uses our dimpled sharkskin product surfaces to prevent the leafy greens from sticking to the scale. This product surface could damage the IQF chicken. I would recommend using an embossed product contact surface on IQF chicken.

No two scales are the same.

So what?

This story highlights just a few examples of how different a scale can be configured depending on the application and the information provided. The high sanitation scale the example actually needed would be three times the price of the original scale discussed, even though all three options were 6-liter combination scales with 14 weigh heads.

I can go into even more detail on options and configurations for scales.

So far, we have discussed three different scale series offered by Yamato: the Alpha Series for dry, free-flowing applications, the Epsilon Series for higher volumes and washdown or IQF products, and the Omega Series for high speed, multiple output, or high sanitation applications.

Now, let’s see how we can configure the components of these scales.

Scale options and configurations are complex.

  • Top Cone (Also referred to as center dispersion cone): The product is loaded onto the scale by dropping it on to the scale’s top cone. There are many different top cone options to choose from based on the application. The angle of the top cone can be increased to help sticky products move onto the linear feed pans. If there is free-flowing product, the angle can be reduced to slow the movement of product onto the scale’s linear feed pans. Yamato offers horned top cones for small granular products. There are also two-stage top cones with different angles to help reduce buildup of sticky product on the center of the scale. There are even different infeed funnels and feed rings that can be used in conjunction with the top cone to ensure even dispersion of product onto the top of the scale. The correct top cone will properly move the product onto the linear feed pans of the scale.
  • Linear Feed Pans (Also known as vibratory feed pans): The linear feed pans use vibratory coils to move the product from the top cone into the feed buckets. In addition to moving the product, the linear feed pans need to be able to accurately control the flow of product into the feed buckets. Overfeeding or underfeeding the feed buckets can negatively affect the performance of the scale. There are over 25 unique styles of linear feed pans Yamato can select from to provide the best flow of your product into the feed buckets.
  • Feed Buckets & Weigh Buckets (Also known as feed hoppers & weigh hoppers): The feed buckets are a staging area for product to be introduced into the weigh buckets. The weigh buckets are where the product weight is measured. There are not a lot of options on the feed buckets or the weigh buckets. A single door or double door could be preferred depending on stickiness of the product. Different product surfaces could be recommended as well: flat for free-flowing products; embossed or sharkskin for sticky products.
  • Collating Chute: Once the product is released from the scale’s weigh bucket, it will drop into a collating chute. Collating chute options can be segmented as the most common option. Baffles can be included to help reduce swirling of product and increase speeds. Yamato also has individual collating chutes available to help increase speeds. There are different chute angles available, too. Steeper, 65-degree angles will increase the speed of the product as it leaves the scale. On the other hand, a 50-degree angle could be used to slow the product down and reduce impact as it exits the chutes. These chutes guide the product charges down into the collating funnel as it prepares to leave the scale.
  • Collating Funnel: The collating funnel of the scale will take the charges from all the buckets used in a combination and combine them together as all the product leaves the scale. The collating funnel can be optioned with baffles to help reduce swirling. The angles of the collating funnels can also be modified like the collating chutes can be. Yamato also has a proprietary Frontier system that utilizes a double-acting weigh bucket and an inside and outside chute to simultaneously collect and drop charges to increase speeds.

I am still not done yet!

Once the product leaves the funnel, we are not done with options!

  • Forming Tube: Some applications will drop right into a forming tube on a vertical form fill seal (VFFS) bagger.
  • Collection Bucket (Also known as a timing hopper): Some applications may benefit from using a collection bucket to collect the charge which can help create charge separation and increase speed. Some collection buckets can be used to reject as well.

In summary…

As you can see, there are quite a few variables and configurations available at Yamato to get you the best-performing combination scale for your application. It is important for you to provide as much information about your application as possible up front so we can select the correct scale for you. Simply asking for a duplicate scale with the same configuration and specs as your existing scale may be okay. However, it’s important to consider a few things before doing so:

  • Have any of your products changed since you last purchased a scale?
  • Do you still need to accommodate that high target weight product?
  • Has your packaging changed at all?

The bottom line:

No two scales are the same.

Hopefully, this information and insight helps you understand some of the complexities and variables that go into selecting the correct Yamato combination scale for your application. Yamato has over 100 different scale models to choose from and over one thousand different configurations to customize the best scale for your needs.

Interested in configuring a scale and receiving a quote for weighing your unique application? Contact us today or email