Pump Separation Device with Relief Channel for Narrower Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pumps suffer from reduced efficiency due to backflow through gaps between rotating and stationary parts, which is exacerbated by the use of inserts that deform or collapse, leading to increased wear and reduced operational safety.
Innovation Solution
A pump design featuring a separation device with a rotary and stationary part, where a non-metallic insert is fixed in an annular recess with a relief channel to the low pressure region, preventing pressure buildup and deformation of the insert, allowing for a narrower gap without wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the width of the gap between the impeller and stationary impeller opening is reduced to decrease backflow and increase pump efficiency, then pump efficiency is improved, but the risk of physical contact between rotating and stationary parts increases, reducing operational safety
Solution Approach 1:
A non-metallic insert (e.g., PEEK material) is introduced as an intermediary component between the rotating impeller and the stationary impeller opening. This insert acts as a mediator that allows for a reduced gap width while preventing direct metal-to-metal contact, thereby maintaining both high pump efficiency and operational safety. The insert is retained by a relief channel that prevents pressure buildup behind it.
Solution Approach 2:
The material parameter of the gap interface is changed from metal-to-metal contact to metal-to-non-metallic-insert contact. This parameter change enables the gap width to be reduced significantly (by up to 50%) while maintaining low friction and wear characteristics, thus improving pump efficiency without sacrificing operational safety.
2Productivity
If a non-metallic insert is used in the stationary part to reduce gap width and improve efficiency, then pump efficiency is improved, but the insert may deform or collapse under pressure, leading to increased wear and reduced reliability
Solution Approach 1:
The high pressure that exists in the region behind the insert (between the insert and the stationary part bottom) is normally harmful as it causes insert deformation. However, the invention converts this harmful pressure into a beneficial retaining force by using the relief channel to prevent pressure buildup, thereby stabilizing the insert against the high pressure from the pump operation.
Solution Approach 2:
The harmful effect of pressure buildup behind the insert is eliminated by extracting or providing a pressure relief path through the relief channel. This channel allows the high pressure fluid to bypass the insert, preventing the pressure accumulation that would cause insert deformation or collapse.
3Loss of energy
If the gap width is reduced to minimize backflow, then energy loss is reduced and pump efficiency is improved, but wear increases due to insert deformation and collapse
Solution Approach 1:
The non-metallic insert serves as a durable intermediary that maintains the reduced gap width configuration over time. By preventing insert deformation through the relief channel design, the insert maintains its dimensional stability and continues to provide low-friction contact, thereby minimizing backflow energy loss without generating excessive wear.
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 design significantly enhances pump efficiency by reducing backflow and maintaining operational safety through the use of a non-metallic insert stabilized by a relief channel, preventing deformation and collapse.
Implementation Method 1
A relief channel is provided, configured for a fluid communication between the bottom of the recess and the low pressure region
Implementation Method 2
a stationary wear ring surrounding the shroud of the impeller with an insert having good friction properties, for example polyetheretherketone (PEEK)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A pump for conveying a fluid is proposed, comprising a stationary housing (2), at least one impeller (5, 51, 52, 53) for conveying the fluid from a low pressure region (LP, HP1) to a high pressure region (HP1, HP2), a shaft (6) for rotating the impeller (5, 51, 52, 53) about an axial direction (A), and a separation device (20) for restricting a flow of fluid from the high pressure region (HP1, HP2) to the low pressure region (HP1, LP), wherein each impeller (5, 51, 52, 53) is mounted on the shaft (6), wherein the separation device (20) comprises a rotary part (7, 35, 70) connected to the shaft (6) in a torque proof manner, and a stationary part (8, 26) configured to be stationary with respect to the housing (2), wherein the rotary part (7, 35, 70) and the stationary part (8, 26) are configured to face each other and to delimit a gap (9) between the stationary part (8, 26) and the rotary part (7, 35, 70), said gap (9) being arranged between the high pressure region (HP1, HP2) and the low pressure region (HP1, LP), wherein the stationary part (8,26) comprises an annular recess (12) facing the rotary part (7, 35, 70), or the rotary part (7, 35, 70) comprises an annular recess (12) facing the stationary part (8, 26), wherein the recess (12) comprises a bottom (121), and wherein a non-metallic insert (13) is provided in the recess (12). A relief channel (14) is provided, configured for a fluid communication between the bottom (121) of the recess (12) and the low pressure region (HP1, LP).