I. Introduction

II. Environmental Factors

1. Temperature

• Temperature changes will cause changes in the physical properties of the elastic elements and measurement media of the pressure gauge. For example, in a high-temperature environment, the spring stiffness of the pressure gauge may decrease, resulting in a higher measured value; while in a low-temperature environment, the viscosity of the medium may increase, affecting the pressure transmission and leading to measurement errors.

• During the calibration process, the environmental temperature should be kept as stable as possible. Generally, it is required to calibrate near the standard temperature (such as 20℃) and correct the errors caused by temperature changes.

2. Humidity

• A high-humidity environment may cause the parts of the pressure gauge to rust and corrode, affecting its normal work and measurement accuracy. Especially for some pressure gauges with electronic components, humidity may also affect the performance of the electronic circuit.

• Calibration should be carried out in an environment with appropriate relative humidity. If necessary, moisture-proof measures can be taken, such as using desiccants.

3. Vibration and Shock

• If there are strong vibration or shock sources near the calibration site, such as the operation of mechanical equipment and construction, it may interfere with the measurement of the pressure gauge, causing the pointer to shake or produce additional errors.

• The calibration should be carried out in a place far from the vibration and shock sources, or take damping measures, such as placing the calibration equipment on a damping table.

III. Equipment Factors

1. Accuracy of the Standard Pressure Gauge

• The standard pressure gauge, as the benchmark for calibration, its own accuracy directly affects the accuracy of the calibration results. If the accuracy of the standard pressure gauge is not high enough or there are errors, it will be difficult to accurately determine the error of the calibrated pressure gauge.

• When selecting the standard pressure gauge, it should be strictly selected according to the accuracy requirements, and it should be verified and calibrated regularly to ensure its accuracy and reliability.

2. Stability of the Calibration Equipment

• The stability of calibration equipment such as the pressure source and the piston gauge also has an important impact on the calibration accuracy. If the pressure output by the pressure source is unstable, or there are problems such as leakage in the piston gauge, it will lead to calibration errors.

• Regularly maintain and check the calibration equipment to ensure its stable performance. Before use, it should be preheated and debugged to ensure the normal operation of the equipment.

3. Influence of the Connecting Pipeline

• If there are problems such as blockage, leakage or elastic deformation in the pipeline connecting the standard pressure gauge and the calibrated pressure gauge, it will affect the pressure transmission and measurement. For example, pipeline blockage will make the pressure transmission unsmooth, resulting in a lower measured value; pipeline leakage will cause pressure loss and a higher measured value.

• Appropriate connecting pipelines should be used to ensure that their inner diameters, materials, etc. meet the requirements, and the sealing and smoothness of the pipeline should be checked before installation.