Gate Valve Sealing System Composite Insert
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sealing systems for industrial gate valves, particularly those using thermoplastic inserts, face issues with optimal sealing at high pressures, manufacturing costs, wear, misalignments, and reliability due to metal-to-metal contact and dirt infiltration, leading to increased production costs and potential valve seizing.
Innovation Solution
A sealing system incorporating a thermoplastic insert and an elastomeric o-ring or delta ring, along with a scraper ring, which reduces pressure stress and prevents metal-to-metal contact, ensuring effective sealing up to 150 bars while minimizing manufacturing costs and maintaining reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a thermoplastic insert is used for sealing between the seat and slab, then the valve can operate with simpler manufacturing and lower costs, but the sealing becomes non-optimal at high pressures and the insert is subject to wear and deformations
Solution Approach 1:
The sealing system uses a composite structure combining a thermoplastic insert (PTFE, nylon, PEEK) with a metal seat body. The thermoplastic material provides low friction and good sealing properties, while the metal seat provides structural strength and pressure resistance. This composite approach allows the valve to maintain reliable sealing at high pressures without requiring complex manufacturing processes.
2Device complexity
If the thermoplastic insert is the exclusive sealing member, then the device complexity is reduced, but the sealing deteriorates under high fluid pressure values exceeding 55 bars
Solution Approach 1:
The invention changes the material parameters by selecting thermoplastic materials with specific properties (PTFE, nylon, PEEK) that have high pressure resistance and low friction coefficients. These material parameter changes enable the sealing system to withstand high fluid pressures exceeding 55 bars while maintaining operational simplicity and avoiding complex multi-component sealing arrangements.
3Stress or pressure
If metal-to-metal contact is used between seat and slab, then the sealing can withstand high pressures, but the valve is prone to definitive seizing and irreparable damage
Solution Approach 1:
The thermoplastic insert acts as an intermediary element between the metal seat and the slab. This intermediate layer prevents direct metal-to-metal contact, reducing friction and wear while maintaining the ability to withstand high pressures. The thermoplastic material deforms elastically to maintain sealing contact without causing the seizing problems associated with metal-to-metal interfaces.
4Manufacturing precision
If the slab surface is accurately machined and lapped to achieve good sealing with thermoplastic material, then the sealing quality improves, but the production costs increase significantly
Solution Approach 1:
The invention changes the material parameters by selecting thermoplastic materials (PTFE, nylon, PEEK) with inherently low friction coefficients and high compliance. These material property changes allow the system to achieve reliable sealing without requiring the slab surface to be lapped or highly polished, thereby significantly reducing manufacturing costs while maintaining effective sealing performance.
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 system achieves optimal sealing at high pressures, reduces torque requirements, and prevents valve seizing, ensuring cost-effectiveness and improved reliability by using less powerful actuators and protecting against dirt and impurities.
Implementation Method 1
a member made of elastomeric material, preferably in the form of an elastomeric O-ring or delta ring, positioned in a housing obtained on the seat and capable of carrying out the sealing on the slab
Implementation Method 2
a member made of thermoplastic material works between the seat and the slab, which is suited to ensure the sealing of the valve while being suited to allow the relative movement between seat and slab
Data Source
Figure 1~2
Figure 3~4
AI summary
The present invention concerns a sealing system particularly for industrial safety valves, even more particularly for industrial gate valves. Hence, the subject of the present invention is both a sealing system (1) suited to be used on a gate valve and a gate valve comprising such a sealing system (1). The system according to the present invention allows to combine the advantages in terms of simplicity and cost-effectiveness for manufacturing gate valves provided with a traditional sealing system, with further advantages in terms of performance both at high and at low operating pressures and reducing the torques required to handle the slab, also ensuring the operation of the valve itself with unaltered sealing performance over time, even under particular and demanding operating conditions.