Rope Packing Seal System for Extreme Temperature BOP Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current blowout preventer (BOP) devices fail to reliably seal at very high or very low temperatures due to the limitations of nitrile rubber, thermoplastic, graphite, and asbestos sealing materials, which degrade or become brittle, leading to seal failure in extreme temperature wellhead applications.
Innovation Solution
The design incorporates a steel-bodied BOP with a rope packing seal system, featuring primary and secondary rope packing seals held in continuous grooves, which can accommodate extreme temperatures by providing a dynamic seal that maintains sealing effectiveness across a wide temperature range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional sealing materials (nitrile rubber, thermoplastic, graphite, asbestos) are used in BOP devices, then sealing function is provided under normal temperature conditions, but the seals fail at very high or very low temperatures due to degradation or brittleness
Solution Approach 1:
The patent employs a composite sealing system combining multiple rope packing materials (such as PTFE, graphite, and other high-temperature resistant materials) layered or combined together to create a seal that functions across extreme temperature ranges from -50°F to 500°F, resolving the contradiction between sealing reliability and temperature adaptability
Solution Approach 2:
The invention changes the material parameters of the seal by using rope packing with specific physical properties (low friction coefficient, high temperature stability) that maintain sealing effectiveness across extreme temperature variations, allowing the seal to adapt its performance characteristics to different temperature conditions
2Temperature
If rope packing seal system is implemented to extend temperature range, then sealing effectiveness is improved at extreme temperatures, but device complexity increases due to multiple seals and grooves
Solution Approach 1:
The sealing system is segmented into primary and secondary rope packing seals positioned in separate grooves, with each seal performing a specific function (primary seal for main sealing, secondary seal for backup and dust sealing), which manages complexity through functional segmentation while achieving extended temperature range capability
Solution Approach 2:
The rope packing seal system is designed to perform multiple functions simultaneously: primary sealing, backup sealing, dust sealing, and accommodation of both tubular members and central bores, reducing overall device complexity by using a universal sealing mechanism for multiple purposes
3Force
If opposing rams are pressed together to seal central bore, then sealing force is sufficient to prevent fluid escape, but rubber material may extrude or tear under high pressure
Solution Approach 1:
The patent changes the material parameters by using rope packing material with high compressive strength and low compressibility that resists extrusion and tearing under high sealing forces, while maintaining the ability to deform sufficiently to create an effective seal against the central bore and tubular members
Data Source
AI summary
A ram type blowout preventer having a seal on each ram, extending across the front face, rearwardly and then over the top portion or the bottom portion of the ram. Each ram forms a leading edge portion above or below the front face seal, so as opposing rams move into the extended sealing position, the leading edge portions of the rams press against each other, imparting a generally vertical movement to bring the seals on the front faces into sealing engagement with each other and to energize the seals extending over the top or bottom portions against the ram bores. The front face of each ram may include a portion which is inclined toward the central bore. Rope packing seals may be provided on the rams having a vertical offset at the front faces of the rams such that rope packing seals on opposing front faces seal against each other.