Gate Valve Sealing with Wedge and Guide Plates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional gate valves in coal gasification plants face operational deficiencies due to particulate material accumulation, poor sealing at high temperatures, and complex maintenance procedures, leading to durability issues and difficulty in preventing fluid entry into the valve box during partial opening.
Innovation Solution
A gate valve design featuring a wedge plate and guide plate with orthogonal sliding surfaces, elastic sealing members, and adjustable urging members to maintain contact pressure, allowing for effective sealing and easy maintenance without disassembly, while preventing particulate material entry and accommodating thermal expansion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a through-conduit gate valve with double sealing structure is used to prevent particulate materials from entering the valve box, then sealing performance is improved, but device complexity increases and seal durability decreases
Solution Approach 1:
The valve body is divided into an upper valve body and a lower valve body that can be separated from each other. This segmentation allows the seal structure to be simpler while still preventing particulate materials from entering the valve box, as each section can be independently designed and maintained without requiring a complex double sealing system.
Solution Approach 2:
The seal structure is extracted and simplified by using a single effective seal between the upper and lower valve bodies, rather than implementing a complex double sealing system. The seal member is positioned to effectively prevent particulate material entry while reducing overall structural complexity.
2Duration of action of stationary object
If multiple gate plates are used sequentially to protect the sealing portion, then durability is improved, but device complexity increases
Solution Approach 1:
A buffer plate is introduced between the gate plate and the seal structure to absorb and distribute the impact and wear. This beforehand cushioning protects the sealing portion from direct contact with abrasive particulate materials, extending its durability without requiring multiple complex gate plates.
3Reliability
If a seal is disposed on a moving portion to prevent particulate material entry, then sealing performance is improved, but the seal has low durability and is easily damaged
Solution Approach 1:
A buffer plate is positioned between the moving gate plate and the seal member to provide beforehand cushioning. This buffer plate absorbs the mechanical stress and protects the seal from direct contact with abrasive forces, significantly improving seal durability while maintaining effective sealing performance.
4Productivity
If the valve is designed with large valve bore for particulate material transport, then flow capacity is improved, but ease of removal for maintenance decreases
Solution Approach 1:
The valve is segmented into an upper valve body and a lower valve body that can be separated from each other. This segmentation allows the valve to maintain a large bore capacity for efficient particulate material transport while enabling easy disassembly and maintenance by simply separating the two valve body sections without requiring complete valve removal from the system.
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 design ensures high durability and improved sealing efficiency, prevents particulate material accumulation, and facilitates easy inspection and maintenance by maintaining contact pressure and surface force adjustments, while maintaining air-tightness and wear resistance in high-temperature environments.
Implementation Method 1
a first sealing member (57) having elasticity is mounted between the inclined surface and a wedge-plate annular groove provided around the wedge-plate channel of the inclined supporting surface; a second sealing member (63) having elasticity is mounted between the guide plate and the outlet portion
Implementation Method 2
the valve box is provided with a first urging member capable of urging the wedge plate to the second end in the opening-and-closing direction, and a second urging member that is disposed at the second end, in the opening-and-closing direction, of the first urging member and that is capable of urging the wedge plate to the first end in the opening-and-closing direction
Data Source
AI summary
An object is to provide a gate valve capable of preventing operational deficiencies caused by particulate materials accumulating in a valve box, thus providing superior sealing properties and high durability, having a simple structure, and allowing inspection and maintenance to be performed easily. A gate valve installed in a transport line for transporting fluid containing particulate material at a coal gasification plant includes a valve box having an inlet portion and an outlet portion in which a channel constituting a part of the transport line is formed; a valve unit, provided between the inlet portion and the outlet portion, which extends in an opening-and-closing direction orthogonal to an axial direction of the channel, and which is movable in the opening-and-closing direction; a wedge plate provided between the valve unit and the inlet portion so as to extend in the opening-and-closing direction; and a guide plate provided between the valve unit and the outlet portion so as to extend in the opening-and-closing direction. Areas between the valve unit and the wedge plate and between and the valve unit and guide plate are sealed by means of surface contact.