How to Find the Best Weighing Operation for Your Manufacturing Process

On January 5, 2022

One of the most common mistakes manufacturing facilities make is not weighing their operations correctly. The first step to avoiding this problem is knowing what you should be doing for each operation, and then following those rules.

There are four main ways to weigh your products:

  1. Counting pieces
  2. Counting by weighing
  3. By weight
  4. By subtracting quantity

Which method you use will depend on how accurate you want your measurements to be and what type of product you are weighing. Let’s walk through best practice recommendations for the execution of an accurate weighing operation.

Understanding Weighing Operations for Manufacturing

Weighing operations are used to measure the amount of ingredients that need to be added into a manufacturing process. The weighing operation is executed by picking up the material from a container and placing it on a scale. The way this is done is dependent on several factors, including:

  1. Product type – With each product type, their different characteristics such as particle size distribution, bulk density, or flowability of materials need to be considered. For example, the best practice for a powder product is not necessarily suitable for a liquid one. A careful evaluation of these physical properties will help you identify the right procedure to follow.
  2. Scale properties – It is essential to determine the proper scale to be used for the weighing operations to obtain correct results. For example, if you are weighing heavy products on a very sensitive scale, it will be difficult for the operator to position them correctly, or even worse, they might overload the pan which would result in wrong measurements and therefore wrong production batches. The scale selected for the execution of the weighing operation must be able to measure the amount you need with the expected accuracy.
  3. Required amount – The less the weighing operation takes, the better for your production scheduling. If you want to minimize the amount of time an operator spends doing weighing operations, it is essential to train operators to evaluate the more convenient option to get the quantity weighed out.

Performing Weighing Operations for Manufacturing

Weighing operations can be very challenging for manufacturers who must manage and precisely measure a variety of products with different physical properties. How you execute your weighing operations will be based on your needs. Four different ways include:

  1. Standing weighing – This is the most common approach to weigh quantity as a mass. An empty container is put on the scale for the measurement of the tare, and then the product is poured into it for the measurement of the gross weight. Tare management functionalities are usually available on scales to show the net weight on the display instead of the gross weight so that operators can easily dose the missing quantity up to the target.
  2. Counting pieces – This is the simplest way to measure the quantity of product required in manufacturing. This process is applicable to products that can be counted quickly and accurately by the operator.
    For example, if the manufacturing of a product requires the use of 10 bottles, the operator can simply count each bottle and declare the total number. However, counting pieces is recommended only for small amounts to minimize the risk of incorrect counting due to human errors.
  3. Counting by weighing – When the amount to be counted goes beyond a few pieces, we need to use an alternative method for measuring the quantity, such as counting by weighing. Knowing the average weight of a unit, the operator can weigh the amount on the proper scale as a mass and get the counted units as a result.
    For example, the production requires 30 bottles of an ingredient. If it is known that each bottle weighs on average 100 grams and there are 50 bottles in a pack, then the operator can put a full pack on the scale and remove bottles until the weight corresponds to the required number of bottles.
    Even though this process requires more time and effort compared with simply counting pieces, it provides more accurate results.
  4. Weighing by difference – This process allows for the execution of the weighing operation by subtracting the quantity from a full container until the subtracted quantity reaches the target value. This is commonly required, especially in the case of liquid components and solutions, which must be picked from the original container via syringes or pump.

AX for Pharma 365™ Weighing and Dispensing Solutions

The AXP365 Weighing & Dispensing™ module of AX for Pharma 365™ supports the manufacturing operators for the execution of weighing processes in compliance with GMP by covering the most common weighing procedures – standard weighing, counting pieces, counting by weighing, and weighing by difference – as outlined above.

It is important to note that AX for Pharma 365™ is not limited to the typical scenarios. Being oriented to the needs of the pharmaceutical industry, the software also offers a wide range of advanced features to cover pharmaceutical business scenarios such as the adjustment of the solution’s physical properties (e.g., pH adjustment), and the fill-up to the target volume.

AX for Pharma 365™ is specifically designed and developed to meet the highest standards of accuracy, reliability, and safety, thus ensuring the quality of the product being manufactured, with benefits on the scrap rate, yield rates, and customer satisfaction. To learn more, download our eBook, How Life Science Companies Can Improve Their Market Value, and contact us today.