Weighing processes can vary widely. A simple process may be fine for one sample, while a more complicated process might not be acceptable for another. A LIMS can help you streamline sample management while recording a full audit trail of your operations. Here are some tips for ensuring the accuracy of your weighing processes. If you don’t have the resources to hire a LIMS consultant, try some of the following solutions. These solutions will improve the accuracy of your process and cut your costs.
Consider the environment. When weighing a material or sample, the surrounding environment will impact its accuracy. Major temperature fluctuations, humidity, and chemical interference can all affect weighing results. To reduce these impacts, consider the presence of protective covers for the weighing instrument. Frequent calibration is another great way to guarantee accurate results. In addition, consider the regulations and requirements affecting your weighing equipment. If you are not sure what your weighing system should withstand, download the white paper “Quality by design.”
Avoid contaminating the environment. When weighing small samples, always keep the weighing chamber clean and free of contaminants. Never touch the weighing chamber with your bare hands, since it can cause errors in the readings. To prevent cross-contamination, use clean forceps to place samples in the center of the pan. You should also keep the weights in the weight box. Rubber or wooden tweezers can prevent your hands from damaging the weights. For extra safety, wear gloves when handling heavy weights.
Weighing equipment should be calibrated according to globally recognized standards. OIML and EA 10/18 standards should be used. Calibration methods must take into account metrology and equipment construction. In addition, the weighing process must have a validation protocol to ensure reproducibility. A competent supplier should be able to help you select the weighing equipment that best suits your application. They can also handle initial set-up and commissioning.
The batching process aims to weigh at least 400 pounds of material. A 100-pound weigh hopper is suspended from three load cells of 200 pounds each, which yields a total capacity of 600 pounds. This method is highly accurate. COOPER Instruments & Systems offers a variety of load cells to meet your weighing needs. Their weighing systems can also be budget-friendly, so you can save money while still getting accurate results.
Large temperature changes may affect the accuracy of your weighing process. In fact, they may even cause the load cell to shift when temperature changes significantly. Fortunately, most load cells today are temperature-compensated, so you don’t need to worry about this problem, if you’re using a gain-in-weight batching system. Just be sure to follow these guidelines to ensure that your weighing equipment works properly. Then, you’ll be on your way to ensuring accuracy and safety.
Another factor to consider is the load cell’s response time. Its response time is an important consideration, as a typical load cell acts like a stiff spring that oscillates. In other words, it needs to settle down within a shorter period than the required weighing period. A fast-response load cell may be a necessity in high-speed checkweighing, rotary filling machines, or batching applications.
Pressure differentials can also cause weighing errors. This can happen when a weigh vessel is installed between a pressurized plant floor and an ambient pressure floor. In this case, you should ensure that the load cells are calibrated to the constant pressure level of the pressurized floor and install the weigh vessel elsewhere. If this is not possible, you can always install the weighing vessel in a different location. If you can’t, consider using a differential pressure sensor instead.
Unlike other weighing processes, mass and weight measurements are not always accurate. The differences in weight and mass can be as much as 0.5%. While mass is typically the most important quantity, gravity is also very sensitive. As such, balances are often used in research and development. Balances should be calibrated regularly for maximum accuracy. These can also be used for gauging the density of materials or substances. The weight of an unknown object is more sensitive than a standard mass.
A weighing system usually consists of a weighing hopper, one or more load cells, and a weight controller. The weighing hopper sends an electrical signal proportional to the load. This signal is then combined by a weight controller. When the weighing system detects a weight reading that is too low, the computer closes the gates and records the next tare. This ensures that the weight of the materials in the weigh hopper is accurate.