Portable lubrication unit for a hydraulic fracturing valve assembly, and method for pre-pressurizing valves

摘要

A method for pre-pressurizing fluid control valves is provided. The fluid control valves may be part of a hydraulic fracturing tree, or may be part of a so-called zipper frac manifold. In either instance, the method uses a lubrication unit for pre-pressurizing the cavity of a valve by injecting lubricant under high pressure. The fracturing tree or zipper frac manifold is useful for conducting hydraulic fracturing operations as part of the completion of a well. Each control valve has an upper lube fitting extending to an upper lube channel which communicates with an upper pocket. Similarly, each control valve includes a lower lube fitting extending to a lower lube channel which communicates with a lower pocket. A pressurized lubricating fluid is forced into the lube fittings to pre-pressurize the control valves prior to the fracturing fluid passing through the control valves. The method of pre-pressurizing the control valve restricts scarring by the fracturing fluid of the internal components of the control valve by equalizing pressure.