Top Drive Torque Measurement via Linkage Strain
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for estimating top drive torque in drilling rigs are inaccurate, particularly during the make-up of threaded connections, with methods like monitoring electrical current or hydraulic power being unreliable, and existing torque measurement tools lengthening the drill string distance.
Innovation Solution
A top drive assembly with a motor, torque restraint, and a linkage assembly coupled to a strain gauge, which measures the strain in pins to estimate torque, allowing for accurate torque measurement by transferring torque through the linkage assembly to a rail and measuring the resulting strain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a sub with torque measurement means is mounted in the drill string, then torque measurement capability is improved, but the distance between the top drive and the lower end of the pipe gripper is lengthened
Solution Approach 1:
The patent introduces a linkage assembly as an intermediary mechanism between the top drive and the pipe gripper. This linkage assembly includes a torque restraint engageable with a rail portion and linkage members coupling the torque restraint to the top drive. The linkage assembly transfers torque from the top drive to the rail through the linkage members, enabling torque measurement without requiring a sub in the drill string, thus avoiding the lengthening problem while still providing accurate torque measurement capability
2Device complexity
If electrical current or hydraulic power is monitored to estimate torque, then measurement implementation is simplified, but measurement accuracy deteriorates
Solution Approach 1:
The patent replaces the electrical/hydraulic measurement approach with a direct mechanical measurement system. Instead of monitoring electrical current or hydraulic power, the invention uses a linkage assembly with linkage members that mechanically transfer torque from the top drive to a rail. Strain gauges or similar sensors directly measure the mechanical strain in the linkage members, providing accurate torque measurement without the inaccuracies associated with electrical or hydraulic power monitoring
Solution Approach 2:
The linkage assembly serves as a mechanical intermediary that directly couples the torque production at the top drive to a measurable strain in the linkage members. This mechanical coupling provides a direct physical relationship between torque and measurement, eliminating the indirect and inaccurate estimation methods based on electrical or hydraulic parameters
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 method provides accurate and repeatable torque measurement, enabling quicker adjustments during drilling operations and improving the control of motor operations, reducing the need for lengthy drill string setups.
Implementation Method 1
a measurement is made of the strain in the linkage assembly imposed by reacting the torque to the rail position
Implementation Method 2
the measured strain in the pin results from a bending moment created by the torque
Data Source
AI summary
A top drive assembly that includes a gauge for measuring strain in a linkage coupling the top drive to a drilling rig frame. The strain measuring gauge, which can be a strain gauge, is disposed on a pin that pivotingly links members of the linkage coupling. When a motor in the top drive assembly operates to rotate an associated pipe string, the torque generated by the motor can be estimated by monitoring strain measured in the pin.