稳定流量决定了钻井液振动筛的筛分。 The steady flow of drilling fluid returned from the wellhead determines the screening of the drilling fluid shaker . The drilling fluid must pass through the vibrating screen, and the cuttings must either pass through the screen or be removed by the screen.
There are three kinds of effects of gas invasion in drilling fluid on the vibrating screen.
1) Gas channeling can cause the volume of drilling fluid to fluctuate, thereby exceeding the capacity of the vibrating screen to handle the drilling fluid flow. This is mainly because the gas mixed in the drilling fluid rapidly expands while the surface of the drilling fluid causes the drilling fluid to fluctuate out of the overflow pipe.
2) The presence of tiny air bubbles in the drilling fluid is the main sign of gas invasion. When the air bubbles expand to fill the pores between the metal wires of the screen, the air bubbles may "stick" to the screen.
3) The foam related to the gas invasion phenomenon will leave a layer of light and wet foam film on the vibrating screen. These foams are too light to pass through the screen under gravity and carry additional drilling fluid to the bottom end of the shaker .
Loss of drilling fluid is usually not obvious enough to be ignored. Under normal circumstances, vibrating screen sprays and defoamers can also be used to break the foam. However, a large amount of drill cuttings are often rinsed with spray as they pass through the screen.
之后会使用真空除气器来清除泥浆中的气体，从而保证其他设备的安全使用。 In some demanding drilling operations, a vacuum degasser will be used to remove the gas in the mud after the drilling fluid shaker , thereby ensuring the safe use of other equipment.