Remotely operated system for use in hydraulic fracturing of ground formations, and method of using same

Abstract

The purpose of this invention is to improve on the safety and to allow more efficient production of subterranean formation during fracturing operations with a reduced down-time, minimal supervision and maintenance expense by utilizing remotely operated ground valves having metal-to-metal, gate and seat seal design operable to maintain a dual sided flow and pressure control. Use of a new 45-degree flow-T connector of a Zipper Manifold in combination with the system described is particularly useful for reducing erosion with proppant-laden fracturing fluid.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This U.S. Utility Application claims priority pursuant to 35 U.S.C. §119(e) to the following U.S. Provisional Patent Application, the specification of which is incorporated herein by reference for all purposes: U.S. Provisional Application Ser. No. 61 / 608,915, titled “Method and Processes for Improved Frac Drilling Operations,” filed Mar. 9, 2012, pending.TECHNICAL FIELD[0002]A remotely operated system for the purpose of safely and cost-effectively conducting hydraulic fracturing of ground formations and method of using same is disclosed. In particular, a system and method utilizing a remotely operated system of ground valves disposed between fracturing equipment and a well bore, is set forth.BACKGROUND OF THE INVENTION[0003]Induced hydraulic fracturing, commonly known as fracking is a technique used to release petroleum, natural gas, or other substances for extraction by utilizing pressurized fluid such as water, brine, foam or the like ...

AI Technical Summary

Benefits of technology

The present invention is a system for fracturing subterranean formations using a plurality of ground valves and an accumulator for controlling the flow of fracturing slurry through the valves. The system is designed to be operated remotely or manually, and the accumulator can be placed at a safe distance from the valves to reduce risks and improve safety. The system is also designed to allow for flexibility and cost-effectiveness in case of damage or compromised parts. The technical effects of this invention include improved safety, flexibility, and lower risks for damage to equipment or personnel.

Problems solved by technology

However, the valves which are placed at the well head to form a well tree (Charismas Tree) are often not capable of containing such pressures, which may cause a blow-up or rupture of the well head, severe damage to the well itself and the fracturing equipment placed nearby.

The manually operated ground valves, however, have proven unsafe and inefficient for the reasons explained below.

First, in a blow-up of the well, the manually controlled valves are in a “Danger Zone,” an area of high probability of injury occurring due to the flying debris from the dismantling well.

If the field personnel are caught around the valves while attempting to manually stop the flow of the fracturing slurry between the stages of the fracturing operation, that person inevitably is exposed to a grave injury.

If the person is outside the Danger Zone at the time of ensuing blow-up, it will not be safe to walk up to the ground valves to manually turn the handweel of the valve in order to prevent further damage to the fracturing equipment.

The fluids introduced into the well are not only highly pressurized but are generally corrosive and abrasive because they are frequently laden with corrosive acids and abrasive propellants such as sharp sand, shale, coal or the like.

In addition to dangers related to manually controlled ground valves, the presently used in the industry ground valves suffer from a number of significant disadvantages due to the known condition called “bleeding back” during which the pressurized fracturing slurry backs up to the fracturing equipment and causes the ground valves to be exposed to the abrasive fluid.

Traditionally utilized plug and / or block valves are one-way valves, having Teflon ball and seat design of the seal, which does not completely seal the cavity of the valve's body causing the valve to relatively quickly pack full with sand and debris (wash out), and become extremely difficult, if not impossible to operate due to buckling up during normal fracking.

This makes the valve impossible to turn.

When in a fully open position, the plug and / or block style valves are not capable of securing a tied seal between the Teflon ball and the seat causing the abrasive and pressurized fluid, sand and other undesirable debris to freely enter the cavity of the valve's body during bleeding back, making the valve eventually inoperable and necessary to replace.

Further, a flow-T connector of a Zipper Manifold for selectively servicing two or more wells typically disposed between s source of pressurized fluid and the well head, receives the fracturing slurry at 90 degree angle, causing further damage to the ground valves positioned in each outlet of the flow-T connector for selectively isolating the fracturing slurry, and the damage to downstream components.

In addition to an unscheduled stoppage of fracturing operation, the replacement becomes cost-prohibitive, if the valves have to be replaced more frequently than their normal operable life time.

If the pumps are not pumping fluid with an applied pressure to do so, they lose their prime and will become desynchronized with one another, rendering the pump inoperable and, ultimately, unable to pump.

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