External Hydraulic Tieback Connector Shock Absorption

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current connectors for tieback external risers in offshore drilling and well production face challenges in securely attaching and detaching from subsea wellheads, particularly in minimizing shock loads and preventing damage to gaskets during engagement and disengagement, which can lead to distortion and inefficiencies in fluid sealing.

Innovation Solution

The proposed connector assembly includes a tubular sleeve with a telescoping guide assembly and locking dogs, utilizing a spring-damper system to absorb energy and control the displacement rate, ensuring a soft landing and preventing gasket distortion, with the locking dogs engaging and disengaging radially through a mechanism of pressurized fluid displacement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional connectors are used for tieback external risers, then the connector can attach to subsea wellheads, but shock loads occur during engagement and disengagement causing gasket distortion and potential damage

Engineering Contradiction:

Improveconnector engagement reliabilityVSAvoidshock loads and gasket distortion

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent incorporates a spring-damper system that provides beforehand cushioning during the engagement and disengagement of the connector. The spring element stores energy and the damper element dissipates energy, collectively minimizing shock loads and preventing gasket distortion before they can cause damage to the connector or wellhead.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The spring-damper assembly acts as an intermediary mechanism between the connector and the wellhead during engagement and disengagement. This intermediary system absorbs and dissipates the mechanical shocks that would otherwise be transmitted directly to the gasket and connector components, thereby protecting them from damage.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Strength

If the connector engages firmly with the wellhead, then secure attachment is achieved, but high shock loads are generated during engagement and disengagement

Engineering Contradiction:

Improveattachment strengthVSAvoidshock loads

Core Design Contradiction:

StrengthVSForce

Solution Approach 1:

The spring-damper system provides beforehand cushioning that allows the connector to engage firmly with the wellhead while minimizing shock loads. The spring element maintains contact force for secure attachment, while the damper element dissipates the high forces generated during engagement and disengagement events.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The system changes the mechanical parameters of the engagement process by introducing elastic (spring) and dissipative (damper) elements. These parameter changes allow the system to maintain strong attachment while modifying the force profile during engagement and disengagement to reduce peak shock loads.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If the connector uses a simple engagement mechanism, then the device complexity is reduced, but the ability to minimize shock loads and prevent gasket distortion is compromised

Engineering Contradiction:

Improveengagement mechanism complexityVSAvoidgasket distortion and shock loads

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The spring-damper assembly serves as an intermediary mechanism that adds functionality without significantly complicating the overall connector design. It provides shock absorption and gasket protection while maintaining a relatively simple integration into the existing engagement mechanism structure.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 effectively minimizes shock loads, prevents gasket distortion, and ensures secure engagement and disengagement of the connector with the wellhead, maintaining fluidic sealing integrity and reducing the risk of damage, thereby enhancing the operational reliability and efficiency of the tieback connector system.

Implementation Method 1

utilizing a spring-damper system to absorb energy and control the displacement rate

Methodology Applied

Scientific EffectSpring: Spring

Implementation Method 2

utilizing a spring-damper system to absorb energy and control the displacement rate

Methodology Applied

Scientific EffectDamping: Damping

Implementation Method 3

locking dogs engaging and disengaging radially through a mechanism of pressurized fluid displacement

Methodology Applied

Scientific EffectHydraulic pressure: Hydraulic Press

Data Source

PatentUS9062513B2External hydraulic tieback connector

Publication Date: 2015.06.23 VETCO GRAY LLC

AI summary

A connector for tie back liners has a tubular housing having at least one interior locking dog window. A setting chamber having a setting piston is located in the housing. A retraction chamber is in the housing, spaced axially from the setting chamber and having a retracting piston. Locking dogs are movably coupled in the locking dog window and axially spaced between the setting chamber and the retraction chamber. An actuating sleeve has a cam surface in engagement with the locking dogs and end portions with the setting piston and the retracting piston. Linking elements are in engagement with the locking dogs and a load shoulder located in the housing. The linking elements extend through linking element windows in the actuating sleeve. A shock absorber on the end of the housing absorbs shock when the connector lands on a wellhead.