Multi-Seat Gate Valve Locking Structure for Reliable Sealing
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Solution Overview
Problem
Existing multi-seat gate valves face challenges in achieving an adequate seal, particularly when dealing with fluids containing solids, due to premature wear and increased emissions in 2-piece designs and high thrust requirements or premature engagement in 3-piece designs.
Innovation Solution
A multi-seat gate valve design featuring a pair of sealing members secured between a bottom edge surface on the gate and locking members until fully closed, using detachable pins or ball bearings for coupling, which balances loads and prevents premature engagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If 2-piece gate valve design with two gates acting as sealing members is used, then sealing capability is improved, but bending load on stem increases causing premature wear on packing
Solution Approach 1:
The gate is divided into three separate pieces: a wedge-shaped gate and two parallel sealing members. This segmentation allows each component to perform its specific function - the wedge provides structural support and load distribution, while the parallel sealing members provide sealing contact with the seats, reducing bending loads on the stem.
Solution Approach 2:
The wedge-shaped gate acts as an intermediary between the stem and the parallel sealing members. It distributes the load from the stem to the sealing members, preventing direct transmission of bending loads to the stem and packing, while still enabling effective sealing.
2Reliability
If 3-piece gate valve with springs is used to maintain relative position, then sealing capability is improved, but required thrust increases and can cause premature engagement with obstructions
Solution Approach 1:
The locking members are designed to be movable during operation, transitioning from a locked state (holding sealing members in place during normal operation) to an unlocked state (allowing free movement during opening/closing). This dynamic behavior enables the system to adapt to different operational phases without requiring excessive thrust.
Solution Approach 2:
The system changes the constraint parameters on the sealing members dynamically - constrained during normal operation to maintain sealing, and unconstrained during opening/closing to allow free movement. This parameter change eliminates the need for continuous spring force and reduces thrust requirements.
3Reliability
If locking members are used to secure sealing members, then sealing reliability is improved, but device complexity increases
Solution Approach 1:
The locking members are integrated with the gate structure, combining the functions of the gate and locking mechanism into a unified assembly. This merging reduces the number of separate components and simplifies the overall valve structure while maintaining sealing reliability.
Solution Approach 2:
The locking members serve multiple functions: they hold the sealing members in place during normal operation, allow free movement during opening/closing, and can be detached to release the sealing members when needed. This multi-functionality reduces the need for separate mechanisms for each function.
Data Source
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AI summary
A multi-seat gate valve with a pair of sealing members separated by a gate wherein each sealing member is secured between a bottom edge surface on the gate and a pair of locking members until the gate valve is at a fully closed position and proper seating is achieved.