Sucker Rod Pump Plunger with Segmented Seals

Solution Overview

Problem

Conventional sucker rod pumps face issues with blowback and slippage of fluids and solids due to limitations in seal durability, speed, depth, and temperature, leading to reduced efficiency and frequent repairs.

Innovation Solution

A pump plunger design with enhanced sealing characteristics, featuring a plunger body with end fittings and multiple nested seals, including a lead, middle, and following plunger seals, which form independent fluid-tight seals with the pump barrel, preventing blowback and prolonging sealing efficacy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional seals and O-rings are used to seal the void between the plunger and barrel, then the pump can operate, but the seals have limitations on operating durability, pump speed, depth and temperature resulting in lost pump efficiency and frequent repairs

Engineering Contradiction:

Improveseal durabilityVSAvoidoperating duration

Core Design Contradiction:

ReliabilityVSDuration of action of moving object

Solution Approach 1:

The seal system is divided into multiple independent seals (lead seal, middle seals, following seal) arranged in series along the plunger. Each seal operates independently to prevent fluid blowback, and the segmented design allows each seal to handle specific portions of the sealing task, improving overall reliability and durability under harsh conditions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Multiple middle seals are nested between the lead seal and following seal, creating a nested arrangement where smaller seal components are positioned within the overall seal pack structure. This nested configuration maximizes the sealing effect within the available space and allows each seal to contribute to preventing blowback at different locations

Inventive Principle:

Principle #7Nested doll (Nesting)

2Reliability

If conventional seals are used, then the pump structure remains simple, but the seals fail under high speed, depth and temperature conditions

Engineering Contradiction:

Improveseal performance under harsh conditionsVSAvoidseal pack structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The seal system is divided into multiple independent seals (lead seal, middle seals, following seal) arranged in series along the plunger. Each seal operates independently to prevent fluid blowback, and the segmented design allows each seal to handle specific portions of the sealing task, improving overall reliability and durability under harsh conditions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The end fittings serve multiple functions: they provide structural support for the plunger, serve as mounting points for the seal packs, and include threaded connections for attaching to the plunger body. This multi-functionality reduces the need for additional separate components, maintaining relative simplicity while achieving improved seal performance

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Productivity

If single seal design is used, then the device complexity is low, but fluid blowback occurs reducing pump efficiency

Engineering Contradiction:

Improvepump efficiencyVSAvoidseal configuration

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The seal system is divided into multiple independent seals (lead seal, middle seals, following seal) arranged in series along the plunger. Each seal operates independently to prevent fluid blowback, and the segmented design allows each seal to handle specific portions of the sealing task, improving overall reliability and durability under harsh conditions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Multiple middle seals are nested between the lead seal and following seal, creating a nested arrangement where smaller seal components are positioned within the overall seal pack structure. This nested configuration maximizes the sealing effect within the available space and allows each seal to contribute to preventing blowback at different locations

Inventive Principle:

Principle #7Nested doll (Nesting)

Data Source

PatentUS9145765B2Plunger for downhole pumps

Publication Date: 2015.09.29 LUBRI PUMP INC

AI summary

A pump plunger for a sucker rod pump includes an elongated plunger body having first and second plunger body ends and a longitudinal plunger body bore extending between the first and second plunger body ends, a first plunger end fitting releasably carried by the first plunger body end of the plunger body, a second plunger end fitting releasably carried by the second plunger body end of the plunger body, a first plunger seal pack sandwiched between the first plunger body end and the first plunger end fitting and a second plunger seal pack sandwiched between the second plunger body end and the second plunger end fitting.