What should be noted during the pressure testing of pressure vessels? What are the regulations?
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This post was last edited by wangjianwei86 on 2011-5-11 11:45. Why are the pressures at the top and bottom of the tower different during pressure testing? What should be noted during the pressure testing of pressure vessels? Are there any regulations and standards?
Normally, the pressure at the top of the tower is lower than that at the bottom, but the pressure at the top of the tower is generally taken as the actual pressure.
The title and the content have nothing to do with each other. It seems to be asking about the pressure testing of the tower. For towers, pressure testing is usually carried out by changing their orientation from vertical to horizontal; in this case, it is necessary to take into account the static pressure of the liquid column. Additionally, since the tower is changed to a horizontal position, the stress on the cylinder body must also be considered.
When the pressures at the top and bottom of the tower differ, it is necessary to take into account the static pressure of the liquid column as well as other factors, such as the effect of rising temperatures on pressure
There should be an appropriate experimental plan; the pressure gauges must be two units that have been calibrated within their valid period. The pressure should be increased slowly in accordance with the specified process curve, and the pressure holding time should not be too long. Additionally, pressure testing is relatively dangerous; clear the area of unrelated personnel. The specific plan should be more explicit.
The horizontal testing before leaving the factory is not much different from the normal pressure testing for containers; the only difference is that the pressure value required takes into account the hydrostatic pressure generated by the liquid column when the tower is filled with liquid
Under normal circumstances, the pressure at the top of the tower plus the hydrostatic pressure of the liquid column equals the pressure at the bottom of the tower. Since pressure testing is intended to evaluate the pressure resistance of the entire tower equipment, it is necessary that the pressure at all locations during the testing process meet the specified values; therefore, only the value at the top of the tower can be used
Consider the static pressure. For hydrostatic testing, it should be carried out in accordance with the company’s quality system documents. Take proper safety measures and keep records.
If it is not a horizontal pressure test, the static pressure generated by the liquid at full level should be taken into account; in the case of a horizontal setup, it is necessary to verify whether the wall thickness of the cylinder meets the required standards
According to the definition in Article 3.4.5 of GB150, the test pressure refers to the pressure at the top of the vessel during a pressure test. Therefore, when performing a pressure test on the tower in an upright position using liquid, if the pressure gauge is installed at the bottom of the tower, the pressure indicated by the gauge must be the test pressure plus the hydrostatic pressure of the liquid column from the top of the tower to the location where the gauge is installed. The precautions for pressure testing containers are in accordance with Article 4.7 of the \"Safety Technical Supervision Regulations for Fixed Pressure Vessels\". Before the on-site hydraulic testing of large towers, the load-bearing capacity of the foundation should be verified, and foundation settlement monitoring should be carried out during the testing process. During horizontal hydraulic pressure testing, make sure to properly support the equipment to prevent the container from bending or deforming due to insufficient rigidity.