Variable-Orifice Valve for Rotary Steering Pressure Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary directional drilling systems face challenges in maintaining optimal pressure drop across the drill bit, which affects the actuation force of steering pads, particularly in varying drilling conditions such as changing wellbore curvature and fluid properties.
Innovation Solution
Incorporation of a variable-orifice valve system within the rotary steering tool, allowing for dynamic adjustment of the pressure drop by varying the aperture size of the valve orifices, enabling real-time adaptation to drilling conditions without altering the drilling fluid flow rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed-orifice valve is used to control pressure drop, then the system structure is simple, but the system cannot adapt to varying drilling conditions such as changing wellbore curvature and fluid properties
Solution Approach 1:
The patent applies the dynamics principle by replacing a fixed-orifice valve with a variable-orifice valve that can dynamically adjust its opening size based on drilling conditions. The valve includes a valve body with an orifice and a movable valve element that changes the effective orifice area, allowing the system to adapt to varying wellbore curvature and fluid properties while maintaining optimal pressure drop for steering pad actuation.
Solution Approach 2:
The patent implements parameter changes by varying the orifice size parameter of the valve to control the pressure drop across the drill bit. By changing the physical parameter of the valve orifice from fixed to variable, the system can adjust flow resistance to maintain consistent steering forces despite changes in drilling fluid properties and wellbore geometry.
2Stress or pressure
If drilling fluid flow rate is increased to maintain pressure drop, then pressure drop is maintained, but drilling fluid consumption increases and hole cleaning efficiency decreases
Solution Approach 1:
The patent changes the parameter control approach from adjusting flow rate to adjusting orifice size. By varying the valve orifice area parameter, the system maintains the required pressure drop across the drill bit without increasing the overall drilling fluid flow rate, thus reducing fluid consumption and improving hole cleaning efficiency.
Solution Approach 2:
The patent extracts the pressure drop control function from the flow rate control mechanism. Instead of maintaining pressure drop by increasing flow rate, the system separates the pressure control function by using a variable-orifice valve to create the necessary pressure differential independently of the main drilling fluid flow rate.
3Force
If steering pad actuation force is increased to maintain trajectory control, then trajectory control improves, but the system cannot adapt to changing wellbore curvature and fluid properties
Solution Approach 1:
The patent applies dynamics by making the valve orifice variable rather than fixed, allowing the steering pad actuation force to be dynamically adjusted in response to changing wellbore curvature and fluid properties. The valve element can move to change the orifice area, thereby controlling the pressure drop and resulting steering forces adaptively throughout the drilling operation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enhances the control over steering pad forces, improving the ability to maintain consistent drilling trajectory and hole cleaning by dynamically adjusting the pressure drop in response to changing drilling conditions, thereby optimizing drilling performance.
Implementation Method 1
a variable-orifice valve that can be controllably actuated to vary the magnitude of a pressure drop across the tool
Implementation Method 2
The lower disk may be rotated in a counter-clockwise direction by a turbine that is driven by circulating drilling fluid
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The disclosed embodiments include systems and methods to improve downhole drilling. A representative system may include a rotary steering tool having a plurality of hydraulically actuated steering pad assemblies, a fluid outlet, and a variable-orifice valve positioned within a primary flow channel of the rotary steering tool, downhole from the steering pad assemblies, and uphole from a drill bit. The valve comprises a valve port having a variable-area orifice that can be controllably varied to dynamically adjust the magnitude of a pressure drop from a tool bore to a wellbore annulus formed by the inner boundary of the wellbore and an outer boundary of the tool.