Convertible Bell Nipple for Drilling and Wireline Operations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing well tools and blow-out preventer systems require time-consuming and inefficient switching between drilling and wireline/slickline operations due to the need to change out bell nipples for shooting nipples, which hampers drilling rate and delays hydrocarbon production.
Innovation Solution
A convertible bell nipple assembly with ACME threads, a thread saver, and an extension sub with LTC threads, allowing for reconfiguration without removing and reassembling the bell nipple, and including valves for fluid flow regulation, enabling seamless transitions between drilling and wireline/slickline operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a bell nipple is used for drilling operations, then fluid flow and cuttings separation are enabled, but the system cannot perform wireline/slickline operations without time-consuming equipment changes
Solution Approach 1:
The bell nipple is designed with multiple functional capabilities through configurable components. The body can be configured with internal threads to receive an adapter sub for wireline/slickline operations or external threads for direct drilling operations. This multi-functionality allows a single bell nipple to perform both drilling and wireline/slickline operations, eliminating the need to change equipment between operations and thereby reducing switching time while improving operational versatility.
Solution Approach 2:
The bell nipple system is divided into separable components including the bell nipple body, adapter sub, and thread saver. The adapter sub can be threaded into the bell nipple body when wireline/slickline operations are required, and removed when drilling operations are needed. This segmentation allows for quick reconfiguration of the system to match operational requirements, reducing the time lost during switching between different operational modes.
2Reliability
If the bell nipple relies on static fluid column for pressure containment, then well pressure can be maintained during drilling, but the system cannot seal against wireline/slickline during wireline operations
Solution Approach 1:
The sealing mechanism is made dynamic by allowing the internal thread configuration to change based on operational requirements. When wireline/slickline operations are performed, the adapter sub with internal threads is installed, creating a dynamic sealing arrangement that can engage with the wireline/slickline tool. When drilling operations are performed, the bell nipple body with external threads provides pressure containment through the static fluid column. This dynamic reconfiguration allows the system to adapt its sealing capability to match the current operational mode while maintaining pressure containment reliability.
Solution Approach 2:
The adapter sub acts as an intermediary component between the bell nipple body and the wireline/slickline tool. It provides the necessary threading interface and sealing mechanism that enables the wireline/slickline tool to connect to the bell nipple system. This intermediary allows the system to transition from a simple pressure-containing structure to a complex sealing arrangement capable of preventing wireline/slickline leakage, thereby improving sealing capability while maintaining pressure containment reliability.
3Strength
If ACME threads are used in the bell nipple, then robust threading is provided for drilling operations, but the threads are vulnerable to impact damage
Solution Approach 1:
A thread saver component is installed over the ACME threads in the bell nipple body to provide beforehand cushioning protection. The thread saver acts as a sacrificial element that absorbs impact forces before they can reach and damage the underlying ACME threads. This protective measure allows the robust ACME threading to maintain its strength and load-bearing capacity while being protected from impact damage during wireline/slickline operations or during handling, thereby preserving thread integrity without compromising the strength of the threading system.
Data Source
AI summary
A bell nipple includes a downhole end configured to sealingly couple to an uphole-end of a blow-out preventer. An uphole end of the bell nipple includes a first set of threads along an inner surface of the bell nipple. A thread saver is configured to be received by the uphole end. The thread saver is configured to protect the first set of threads from impact. An extension sub is configured to be received by the uphole end. The extension sub includes a downhole end with a second set of threads configured to engage with the first set of threads. An uphole end of the extension sub includes a third set of threads configured receive a well tool.