Desalter Bushing Seal with Biasing Component
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Desalter entrance bushings fail due to loosening of sealing surfaces under temperature and pressure fluctuations, primarily because the sealing surfaces do not sufficiently compress when the insulating rod is cold or when pressure and temperature drop during production upsets.
Innovation Solution
A novel desalter entrance bushing assembly with an insulating rod, biasing component, and hub nut design that applies a force of at least 350 PSI to maintain a seal between the insulating rod and flange, using a biasing component that compresses the sealing surfaces to an interference fit when tightened to a predetermined torque of at least 50 ft/lb.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a mechanical seal is used between insulating rod and flange, then the seal prevents crude oil contamination under normal conditions, but the seal fails under temperature and pressure fluctuations
Solution Approach 1:
The patent changes the physical state and mechanical properties of the sealing surfaces by heating the insulating rod to operational temperature before final assembly. This thermal treatment modifies the material properties of PTFE, enabling proper compression and interference fit that maintains seal integrity under temperature and pressure fluctuations.
Solution Approach 2:
The patent performs preliminary heating and pre-compression of the sealing surfaces before final installation. The insulating rod is heated to operational temperature in advance, and a pre-load is applied to compress the sealing surfaces, creating a stable interference fit that prevents seal failure during subsequent pressure and temperature changes.
2Ease of operation
If the insulating rod is installed when cold, then installation is easier, but the sealing surfaces do not sufficiently compress and the seal fails
Solution Approach 1:
The insulating rod is preliminarily heated to operational temperature before assembly to ensure proper sealing surface compression. This preliminary thermal treatment enables the material to achieve its operational mechanical properties, ensuring sufficient compression and seal reliability while maintaining ease of installation through standardized procedures.
Solution Approach 2:
The patent changes the temperature parameter of the insulating rod from ambient to operational temperature during installation. This parameter change ensures that the PTFE material has the appropriate mechanical properties for creating a reliable seal, transforming the installation process from a simple mechanical assembly to a thermally-assisted assembly procedure.
3Ease of manufacture
If hub nut is torqued to specified torque, then assembly meets industry standards, but sealing surfaces loosen under pressure and temperature fluctuations
Solution Approach 1:
The patent applies a pre-load force parameter in addition to the standard torque specification. By heating the insulating rod and applying a predetermined pre-load to the hub nut, the sealing surfaces achieve proper compression that maintains seal integrity under operational fluctuations, while still meeting industry torque standards for assembly.
Solution Approach 2:
A preliminary heating and pre-loading step is inserted into the assembly process before final torque application. This preliminary action ensures that the sealing surfaces are properly compressed and interlocked before the final torque is applied, preventing loosening under pressure and temperature changes while maintaining compliance with industry standards.
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
The assembly effectively maintains a seal under temperature and pressure fluctuations, preventing seal failure and extending the lifespan of the bushing.
Implementation Method 1
a biasing component configured to apply a spring force onto the insulating rod to compress the sealing surfaces into an interference fit
Data Source
AI summary
A method and assembly for improving and maintaining a seal between an insulating rod and a flange in a desalter entrance bushing assembly. The assembly includes an insulating rod with a shoulder for a biasing component, a hub nut with a spring seat for a biasing component, a biasing component, and a flange to which the insulating rod can create a fluid tight seal. The shoulder and spring seat can form approximately 90-degree platforms on which the biasing component can apply force when the hub nut is appropriately secured to the flange. The method includes threading the hub nut containing the biasing component into the flange. The nut is secured to a predetermined torque and the biasing component ensures that the seal is maintained during temperature and pressure fluctuations.