English
The performance and accuracy of Industrial Test Weights can be affected by temperature and humidity, especially when used for high-precision measurements or over long periods of time. This effect is primarily due to the physical properties of the material, thermal expansion and contraction, and hygroscopicity. Here are some specific effects of temperature and humidity on Industrial Test Weights and their causes:
Temperature Effects
Thermal Expansion and Contraction Effects
Problem Description: Weights made of materials such as stainless steel, brass, cast iron, etc., expand and contract at different temperatures, causing their volume and mass to change.
Impact:
When the temperature rises, the weight expands in volume, which may cause small changes in mass.
In extreme temperature conditions (such as high or low temperatures), this change may accumulate to the point where it affects high-precision measurements.
Solution:
Use materials with low thermal expansion coefficients (such as Invar alloys), which are insensitive to temperature changes.
Perform calibration and measurements in a constant temperature environment to reduce the effects of temperature fluctuations.
For applications that require extremely high accuracy, temperature compensation techniques or reference standards can be used to correct for temperature effects.
Heat Transfer and Thermal Balance
Problem Description: When a weight is transferred from one environment to another (e.g. from a lab to a workshop), it takes time for the weight to reach thermal equilibrium with the surrounding environment. During this process, the temperature of the weight may temporarily deviate from the ambient temperature.
Impact:
If the weight does not fully reach thermal equilibrium, its density and volume may change temporarily, affecting the measurement results.
Solution:
Place the weight in the target environment in advance to ensure that it is fully acclimatized to the temperature conditions.
Avoid touching the weight directly with your hands, as the temperature of your hands may change the temperature of the weight surface.
Effect of Humidity
Hygroscopicity
Problem Description: Some materials (such as some types of stainless steel or coated materials) may absorb moisture in a high humidity environment, causing the weight to increase in mass.
Impact:
Moisture absorption can cause small but significant changes in the weight of the weight, especially in high-precision applications.
Adsorbed moisture can also cause surface corrosion or contamination.
Solution:
Use materials with good moisture resistance (such as high-quality stainless steel or specially treated surface coatings).
Store and use weights in low humidity environments.
Clean the weight surface regularly to prevent moisture from remaining.
Corrosion and Oxidation
Problem description: In high humidity or humid environments, weights may corrode or oxidize faster due to the presence of moisture, especially for some metal materials (such as cast iron or unprotected brass).
Impact:
Corrosion can cause the weight surface to become rough or change in mass, which can affect measurement accuracy.
The oxide layer may increase the weight of the weight or change its surface characteristics.
Solution:
Choose corrosion-resistant materials (such as stainless steel or nickel-plated weights).
Use sealed containers or desiccant to store weights and avoid exposure to moisture.
Regularly check the weight surface for signs of corrosion and deal with it in a timely manner.
Combined impact: the interaction between temperature and humidity
The coupled effect of temperature and humidity
Problem description: The combined effect of temperature and humidity may aggravate the mass change of the weight. For example, in a high temperature and high humidity environment, the weight will not only change due to thermal expansion and contraction, but may also cause additional mass increase due to moisture absorption.
Impact:
This coupling effect is particularly evident in extreme environmental conditions and may cause measurement errors beyond the acceptable range.
Solution:
Handle and store weights in a constant temperature and humidity environment.
Use high-performance materials (such as Invar alloy or specially treated stainless steel) to make weights to reduce the effects of temperature and humidity.
Precautions in practical applications
Environmental control
In precision measurement situations, it is recommended to store weights in a constant temperature and humidity environment (usually 20°C ± 2°C and 45% ± 5% RH).
Use air conditioning or dehumidification equipment to maintain stable environmental conditions.
Calibration and adjustment
Calibrate weights regularly, especially in environments where temperature and humidity conditions change frequently.
Record the data of each calibration to track the quality trend of weights.
Operation specifications
Avoid touching weights directly with your hands to prevent sweat or grease from affecting their surface properties.
Use special tools (such as tweezers or gloves) to handle weights.
Through strict control of environmental conditions and regular maintenance, the effects of temperature and humidity on industrial test weights can be minimized, thereby ensuring the accuracy and reliability of measurement results.
