Company: Liaoyang Xiangyue Sealing Engineering Co., Ltd.
Address: 24 buildings in Longdingshan C District, Hongwei District, Liaoyang City, Liaoning Province
Mobile phone: +86-18041906362
Customer service hotline: +86-18041906362
Forms and factors of valve leakage
2.1 Leakage of Valve Packing and Causes of Pressure Opening
During the operation and use of the valve, there is relative movement between the stem and the packing, which includes rotation and axial movement. With the increase of the number of switches, the number of relative motion increases, as well as the influence of temperature, pressure and the characteristics of fluid medium, valve packing is the most vulnerable part of leakage. It is due to the gradual weakening of contact pressure of fillers, aging of fillers themselves, loss of elasticity and other reasons. At this time, the pressure medium will leak out along the contact gap between the filler and the valve stem, which will blow part of the filler away and wash the valve stem out of the groove for a long time, so as to expand the leakage.
2.2 Flange Leakage
The flange seal of the valve mainly relies on the pre-tightening force of the connecting bolt to achieve sufficient sealing specific pressure through the gasket to prevent the leakage of the sealed pressure fluid medium. There are many reasons for its leakage, such as the insufficient pressure of sealing gasket, the roughness of the joint surface does not meet the requirements, the gasket deformation and mechanical vibration, etc. will cause the leakage of sealing gasket and flange joint surface. In addition, bolt deformation or elongation, gasket aging, resilience decline, cracking, etc. will also cause flange surface seal lax and leakage. There are also human factors that can not be neglected in flange leakage, such as the deviation of sealing gasket, insufficient tightening force of local sealing pressure, exceeding the design limit of sealing gasket, uneven force in flange tightening process or deviation of the center line of two flanges, which are prone to leakage.
2.3 Valve Body Leakage and Causes
The leakage of the valve body is mainly caused by casting or forging defects in the production process of the valve, such as sand holes, gas holes, cracks, etc. The erosion and cavitation of the fluid medium are also common factors causing the leakage of the valve body.