| 摘要 |
A casing or tubular fill and circulator assembly is indicated, wherein a singular valve is used for filling and circulating the casing as well as providing for pressure equalization when the singular valve is in the open position. The valve is constructed so that it is opened upon being inserted into the upper end of the casing. For filling the casing, only the valve is inserted into the upper end of the casing whereupon the valve is fully opened so that fluid can be pumped into the casing without a pressure drop or erosion of any of the valve members. For circulation, the apparatus is advanced further into the casing until a cup seal closes off the top of the casing. Once flow is initiated in that condition, internal pressure in the casing, at very low applied pressures, will begin the circulation through the casing. With the valve in the fully open position, erosive effects from flow are eliminated during filling and circulation. Additionally, with the cup seal in the casing and the valve fully open, the pumps can be stopped and pressure equalization will occur through the fully opened valve without restriction or delay. |
