Check Valve Packing Structure for Leak Tightness and Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lift type check valves experience issues with water stopping performance and durability of the packing, particularly in underwater installations, where leakage is a concern and the packing is subjected to dynamic, thermal, and chemical loads.
Innovation Solution
The check valve design incorporates a packing configuration where the contact surface between the packing and the valve seat is perpendicular to the reciprocating direction, dispersing stress symmetrically and reducing the impact of repeated contact, with the packing fitted in a recessed area to enhance durability and prevent removal, and a guide washer that supports the packing uniformly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the packing is made of elastic material to ensure water stopping performance, then the packing can be brought into close contact with the valve seat, but the durability of the packing deteriorates under dynamic load, thermal load, and chemical load
Solution Approach 1:
The patent changes the geometric parameters of the packing, specifically designing a recessed structure with specific depth and width ratios. This structural parameter change allows the packing to distribute stress more effectively, improving durability while maintaining water stopping performance through elastic deformation capability
Solution Approach 2:
The recessed structure of the packing acts as a pre-designed stress distribution mechanism that cushions the impact of dynamic loads before they reach the critical contact points. The recessed geometry provides a buffer zone that reduces peak stresses during valve operation cycles
2Duration of action of stationary object
If the contact surface between packing and valve seat is perpendicular to reciprocating direction to disperse stress symmetrically, then durability is improved, but water stopping performance may be compromised
Solution Approach 1:
The patent employs asymmetric design in the recessed structure where the depth and width ratios are specifically optimized. This asymmetric geometry creates a stress distribution pattern that simultaneously achieves symmetric stress dispersion for durability and maintains adequate contact pressure for water stopping performance
3Duration of action of stationary object
If the packing is fitted in a recessed area to prevent removal and enhance durability, then the packing is secured, but the complexity of the valve structure increases
Solution Approach 1:
The recessed structure for the packing is merged with the existing valve body geometry rather than being a separate component. This integration approach secures the packing in place and enhances durability while minimizing additional structural complexity by combining multiple functions into a single integrated feature
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 configuration significantly enhances the water stopping performance and durability of the packing, allowing for long-term use and reduced leakage, even under high flow rates and dynamic pressures.
Implementation Method 1
The packing is made of a material having elasticity, such as a rubber material
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A reciprocating body (2) has a valve element (6) which includes a deflecting surface (10a), a valve shaft (7) which is guided by a guide cylinder (4), and a packing (8) having an annular shape which is circularly brought into close contact with a valve seat (12a) in a state where the reciprocating body (2) is in a closed position. The valve element (6) includes a large diameter portion (9a), and a small diameter portion (9b) and a deflecting portion (10) extending from the large diameter portion (9a) toward the primary flow passage side. The large diameter portion (9a) has, on the primary flow passage side, a flange surface (9d) which supports the packing (8) in a state where the packing (8) is exposed to the primary flow passage side. The flange surface (9d) is formed such that the flange surface (9d) is allowed to come into contact with the valve seat (12a) via the packing (8). A recess (9c) is formed on the outer periphery of the small diameter portion (9b), and a portion of the packing (8) is fitted in the recess (9c).