Centrifugal Pump Suction Nozzle Axial Gap Adjustment
Solution Overview
Problem
Centrifugal pumps face challenges in maintaining hydraulic efficiency over long-term operation due to wear-induced increases in the axial gap between the impeller and the suction port, which existing adjustment methods are not well-suited to address effectively.
Innovation Solution
The centrifugal pump design features an axially displaceable suction nozzle with a sealing collar that allows precise adjustment of the gap size and sealing, eliminating the need for complex manufacturing processes and tools, and incorporates a V-ring seal for enhanced sealing and reduced friction during operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a conventional O-ring seal is used for radial sealing between the suction port and base plate, then sealing is provided, but considerable force is required to rotate the suction port and the manufacturing complexity increases due to radial grooves and undercuts
Solution Approach 1:
The sealing function is extracted from the suction port itself and transferred to a separate sealing collar component. The sealing collar is mounted on the suction port's radial circumferential surface and provides sealing against the base plate without requiring radial grooves or undercuts in the suction port, thereby simplifying suction port manufacturing while reducing rotational friction.
Solution Approach 2:
The sealing collar acts as an intermediary element between the suction port and the base plate. It provides the sealing interface and friction reduction function, allowing the suction port to rotate with minimal force while maintaining effective sealing, without requiring complex features on the suction port itself.
2Loss of energy
If the axial gap between impeller and suction port is reduced to minimize hydraulic losses, then hydraulic efficiency is improved, but the system becomes more sensitive to wear and manufacturing tolerances
Solution Approach 1:
The suction port is made dynamically adjustable through rotation about its central axis. By rotating the suction port, the axial position of the impeller relative to the suction port can be changed, allowing the gap to be optimized for minimal hydraulic losses. This dynamic adjustment capability compensates for wear and manufacturing tolerances while maintaining low energy losses.
Solution Approach 2:
The axial gap parameter can be changed by rotating the suction port to different angular positions. This allows optimization of the gap dimension to minimize hydraulic losses during assembly and operation, while the ability to adjust the parameter compensates for wear over time.
3Duration of action of stationary object
If height-adjustable base plate or suction port designs are used to compensate for wear, then long-term efficiency is improved, but the device complexity and adjustment difficulty increase
Solution Approach 1:
The suction port is designed to rotate about its central axis, providing a simple dynamic adjustment mechanism. This rotational movement allows axial position adjustment of the impeller relative to the suction port to compensate for wear, extending the service life while maintaining efficiency without requiring complex height-adjustable mechanisms.
Solution Approach 2:
The suction port, sealing collar, and base plate are preferably made from the same material (glass fiber reinforced plastic), simplifying manufacturing and assembly. The homogeneous material selection reduces complexity while the rotational adjustment mechanism provides the necessary wear compensation for extended service life.
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
This design ensures high hydraulic efficiency by minimizing volume flow loss and allowing for easy, cost-effective adjustment of the gap size without special tools, maintaining efficiency even under wear conditions, and reducing manufacturing complexity.
Implementation Method 1
incorporates a V-ring seal for enhanced sealing and reduced friction during operation
Implementation Method 2
The injection-molded suction port allows for smooth running and friction-free rotation about its central axis
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a centrifugal pump with a pump housing (1), wherein an impeller (2) and a suction nozzle (4) forming a suction opening and which can be inserted into a base plate (3) of the pump housing are arranged in the pump housing (1), the suction nozzle (4) is axially displaceable on the base plate (3) of the pump housing in such a way that the suction nozzle (4) and the base plate (3) each have at least one surface (6) pivoted relative to the base plate (3) and abutting each other, so that by rotating the suction nozzle (4) a distance between the impeller (2) and the suction nozzle (4) can be changed, and the surfaces (6) are pivoted such that by rotating the suction nozzle (4) in the direction of rotation of the impeller (2) the distance is reduced.