Mixing Blade End-Cap Structure for Heated Fluid Leak Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mixing blades made of carbon steel or stainless steel suffer from porosity, leading to fluid leakage and contamination during heating, necessitating time-consuming and difficult repairs due to their large size and in-place welding limitations.
Innovation Solution
A mixing blade design featuring end caps and stub shafts with internal passageways, sealed by weld plugs, to prevent fluid leakage and allow for efficient heating/cooling, reducing the need for blade removal during repairs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If an internal passageway is formed within the blade to allow heated fluid to pass through, then the heating time is reduced from 24 hours to about one hour, but the inherent porosity of the casting creates pathways for heated fluid to escape to the surface, causing contamination
Solution Approach 1:
The patent applies the principle of porous materials by intentionally creating a porous coating layer on the blade surface through thermal spray application. This porous layer acts as a barrier that allows the blade to benefit from the internal passageway heating while preventing fluid leakage through the casting porosity. The porous structure of the coating accommodates the underlying porosity without allowing fluid escape.
Solution Approach 2:
The patent applies composite materials by combining the metal blade substrate with a thermally sprayed coating layer. This composite structure integrates the functional benefits of the internal passageway system for rapid heating while the coating material seals the porosity pathways. The coating can be composed of multiple layers including bond coat and top coat, creating a composite barrier system.
2Ease of manufacture
If the ends of the blade are machined, then the blade can be fitted and connected to the mixer vessel, but new pathways are opened or created for heated fluid to escape from the internal passageway to the machined ends
Solution Approach 1:
The thermal spray coating is applied to cover the machined end surfaces, creating a porous barrier layer that seals the pathways opened by machining. The coating material fills and seals the machined surfaces while maintaining the overall fit and connection capability of the blade to the mixer vessel.
Solution Approach 2:
The coating is applied to the blade ends before final installation, preemptively sealing the machined surfaces before they can serve as leakage pathways. This preliminary protective action ensures that when the blade is installed and connected, the ends are already sealed against fluid escape.
3Ease of repair
If the blade is removed from the mixer vessel for repair, then welding repairs can be performed on the blade ends, but the process becomes very time consuming and difficult due to the size, weight, and interconnection of the blade
Solution Approach 1:
The blade is segmented into modular components with connection interfaces at the ends. The stub shafts and connection features allow the blade to be divided into separable sections that can be independently removed and repaired. This segmentation enables repair of specific portions without requiring removal of the entire blade assembly from the mixer vessel.
Solution Approach 2:
Stub shafts serve as intermediary components between the blade body and the mixer vessel mounting system. These stub shafts can be independently removed and replaced, allowing repair access to the blade ends while the blade remains in position. The stub shafts mediate the connection, enabling maintenance without full blade removal.
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 improved blade design significantly reduces fluid leakage and simplifies repairs by maintaining fluid integrity within the blade, minimizing the need for blade removal from the mixer vessel.
Implementation Method 1
a porous coating is applied to the blade by a thermal spray process
Implementation Method 2
the porous coating prevents leakage of the fluid through the blade
Data Source
AI summary
A mixing blade includes a first end of the blade having a first face and a second end of the blade opposite the first end of the blade and having a second face. A first blade face and a second blade face are disposed between the first end and second end. A first end cap that has an outer face and an inner face with the inner face abutting the first face of the first end of the blade. A second end cap that has an outer face and an inner face with the inner face abutting the first face of the second end of the blade.