Opposing Offset Fluid End Bores for Plunger Pump Stress Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional high-pressure plunger pumps in oil field operations face issues with fatigue cracking due to alternating pressures, and existing Y-block designs complicate maintenance while offering limited stress reduction.
Innovation Solution
The design incorporates opposing offset bores in the fluid end housing, reducing stress concentrations and improving maintenance accessibility by using elongated cylindrical cross-sections and chamfered transitions, allowing for easier installation and removal of valve components without the need for complex retainer arms or threads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional fluid end housing designs with collinear bores are used, then manufacturing is simpler, but stress concentrations increase leading to fatigue cracking
Solution Approach 1:
The patent applies asymmetry by offsetting the bores from a collinear arrangement to asymmetric positions that avoid stress concentration zones. The first bore is offset from the second bore, and both are offset from the third bore, creating an asymmetric configuration that reduces stress concentrations while maintaining structural integrity.
Solution Approach 2:
The patent transitions from a two-dimensional planar arrangement of bores to a three-dimensional spatial configuration. The bores are offset in multiple directions and planes, utilizing the third dimension to space bores away from each other and avoid intersecting stress concentration zones that would occur in a flat arrangement.
2Strength
If Y-block designs are used, then stress concentrations are reduced, but maintenance accessibility worsens and device complexity increases
Solution Approach 1:
The patent segments the fluid end housing into distinct regions with bores positioned in separate zones. By offsetting the bores rather than concentrating them in a Y-block configuration, each bore has its own accessible region, allowing maintenance personnel to reach valve components independently without navigating complex intersecting bore structures.
Solution Approach 2:
The bore offsets are designed in advance to pre-establish clear access paths to valve components. The positioning of bores away from each other creates predetermined maintenance corridors that facilitate easier installation and removal of valve components without requiring disassembly of complex retainer structures.
3Ease of operation
If opposing offset bores are used, then maintenance accessibility improves and stress concentrations reduce, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies local quality by providing different characteristics in different regions of the housing. The bore offset distances and angles are specifically optimized for the local maintenance access requirements and stress distribution patterns, rather than using a uniform configuration throughout. This allows precise positioning where needed while maintaining manufacturing feasibility.
Solution Approach 2:
The patent utilizes parameter changes by varying the offset distances and angular relationships between bores. Instead of fixed rigid specifications, the design allows optimization of bore positioning parameters (offset distances, angles, and depths) to balance manufacturing precision requirements with maintenance accessibility and stress reduction goals.
Data Source
AI summary
A plunger pump fluid end housing in which the access, suction, and discharge bores within each fluid chamber are offset from the plunger bores. The plunger bore centerline being fixed by the spacing in the pump power end section. The access, suction, and discharge bores in the outside fluid chambers of the pump are offset toward the center of the fluid end. The direction of the offset of the outside fluid chambers opposes the direction of offset of the opposite outside fluid chambers. A special access bore plug with asymmetrical integral spacers is also disclosed.