Rotary Pump Mechanical Seal External Locking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotating pumps face challenges in achieving a secure seal, particularly in hygienic and toxic environments, due to the complexity of mechanical seals and the difficulty in assembling and maintaining them without compromising the product flow or risking damage during assembly.
Innovation Solution
A rotating pump design featuring a mechanical seal with an external positive position lock that prevents twisting and axial movement, utilizing a sleeve with a circumferential groove and a locking plate that engages in the groove for secure positioning, allowing for simplified assembly and maintenance without separating the product space from the pump drive.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a mechanical seal with a stationary section mounted in the wall is used to ensure a secure seal, then sealing reliability is improved, but the assembly complexity increases and the stationary section cannot be mounted from outside the product chamber
Solution Approach 1:
The mechanical seal is divided into a rotating section and a stationary section that can be assembled separately. The stationary section with the locking mechanism can be mounted independently from outside the product chamber, while the rotating section is mounted from the product side, allowing simplified assembly without requiring complete disassembly of the pump.
Solution Approach 2:
The locking mechanism is positioned in a different spatial dimension (outside the product chamber on the backside of the wall) to achieve the locking function without interfering with product flow paths. This allows the seal to be secured against rotation and axial movement without placing components inside the product chamber.
2Reliability
If the stationary section is secured with a flange or receptacle fixed by multiple screws or shrink-fitting, then axial securing is improved, but the assembly process becomes more complex and time-consuming
Solution Approach 1:
The locking function is extracted from the product chamber interior and placed on the backside of the wall. The locking mechanism consists of a locking element that engages with a locking recess in the stationary section, providing simple axial and rotational securing without requiring complex flange assemblies or multiple fasteners.
Solution Approach 2:
Instead of securing the stationary section from the product chamber side using complex flanges, the locking mechanism secures it from the opposite side (backside of the wall). The locking element is inserted from outside the product chamber and engages with the stationary section to prevent both rotation and axial movement.
3Ease of manufacture
If the shaft must be completely removed from the product chamber for seal installation, then seal installation is possible, but productivity decreases and the risk of seal damage increases
Solution Approach 1:
The seal assembly is segmented into components that can be installed from different sides. The stationary section with the locking mechanism is installed from outside the product chamber, while the rotating section is installed from the product side with the shaft still in place, eliminating the need to remove the shaft completely and reducing maintenance time.
Solution Approach 2:
The locking mechanism is pre-assembled with the stationary section before installation. This preliminary preparation allows the stationary section to be quickly secured from outside the product chamber without requiring complex assembly operations after the shaft is removed, thereby reducing overall maintenance time and minimizing the risk of seal damage during assembly.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a rotating pump with at least one driven conveying element (7, 8) which is arranged in a product chamber (77) through which the product to be conveyed flows and is driven by means of a shaft (9, 10) projecting from the outside into the product chamber (77), wherein the shaft is sealed against a wall (57) of the product chamber (77), and wherein the seal is designed as a product-side mechanical seal (61, 62) with an external positive locking device (81), the locking device (81) is designed to prevent the mechanical seal (61, 62) from twisting and from being displaced in the direction of the product chamber (77).