Replaceable Process Seal Pre-Aging for Accurate Pressure Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Thermoplastic sealing materials in pressure sensors experience creep and settling, leading to reduced structural height and clamping forces, making it difficult to replace process seals without affecting measurement accuracy and requiring recalibration, especially when the elastic element is no longer accessible due to potting material filling the sensor housing.
Innovation Solution
A pre-aged process seal with a form-retaining core coated in thermoplastic material, pre-clamped in a geometry-matched clamping apparatus to stabilize the seal's thickness and elasticity, allowing for easy replacement without altering clamping forces or measurement characteristics, and featuring a post-treatment to remove excess material and ensure consistent performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If thermoplastic sealing material is used for process seal, then chemical durability is improved, but elasticity and creep resistance deteriorate
Solution Approach 1:
The process seal is constructed as a composite material system combining a form-retaining core (made of chemically resistant materials like PTFE, PFA, or FEP) with an elastomeric material layer. This composite structure allows the core to provide chemical durability while the elastomeric layer provides the necessary elasticity and creep resistance, resolving the contradiction between chemical durability and mechanical stability.
Solution Approach 2:
The invention changes the material parameter composition by using a core made of thermoplastic sealing material with specific chemical resistance properties, coated or combined with elastomeric material. This parameter change in material composition allows simultaneous achievement of chemical durability from the core and elastic properties from the elastomeric layer.
2Ease of repair
If process seal is replaced, then sealing maintenance is improved, but measurement accuracy deteriorates due to clamping force changes
Solution Approach 1:
The process seal is pre-aged under controlled conditions before installation to allow the thermoplastic material to complete its creep and settling process in advance. This preliminary action ensures that when the seal is installed and later replaced, the clamping forces have already stabilized, preventing measurement accuracy deterioration upon replacement.
Solution Approach 2:
The invention applies controlled thermal and mechanical parameters during the pre-aging process, exposing the process seal to elevated temperatures and clamping forces that accelerate creep and settling. This parameter change in the pre-treatment process stabilizes the seal's dimensional properties before installation, ensuring consistent clamping forces during operation and after replacement.
3Stability of the object's composition
If elastic element is used in clamping apparatus, then compensation for creep is improved, but accessibility for adjustment deteriorates when potting material is applied
Solution Approach 1:
The process seal is pre-aged and pre-adjusted before the sensor housing is sealed with potting material. This preliminary action includes installing the process seal and adjusting the elastic element's prestress while the adjustment mechanism is still accessible. Once pre-aged and adjusted, the seal and clamping system are sealed with potting material, which then protects the adjusted state and eliminates the need for future adjustments.
Solution Approach 2:
The pre-aging process allows the process seal to self-adjust and stabilize under controlled conditions, reducing the need for manual intervention. The elastic element is pre-adjusted to provide appropriate prestress, and the potting material then maintains this adjusted state without requiring further accessibility for adjustment, enabling the system to serve itself.
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
Enables the simple replacement of process seals without affecting measurement accuracy or requiring recalibration, maintaining consistent clamping forces and ensuring high-quality sealing, even after multiple replacements, thus enhancing the operational reliability and hygiene of pressure sensors.
Implementation Method 1
thermoplastic sealing materials do not have sufficient elasticity and creep under pressure
Implementation Method 2
a clamping apparatus for clamping the pressure sensitive means and the process seal between an outer edge of the front face of the pressure sensitive means and a sealing surface of the process connection, wherein the clamping apparatus comprises an element, which is elastic in a direction extending in parallel with a surface normal to the front face of the pressure sensitive means and which is under a prestress
Data Source
AI summary
The present disclosure discloses process seals having a form retaining core and a coating of a thermoplastic sealing material for pressure sensors. The process seals can be replaced in simple manner, especially essentially without loss of measurement accuracy. The process seals are characterized by features including that they are pre-aged in a pre-aging method performable in a reproducible manner and insertable in the pressure sensor as replaceable components, wherein the process seals were clamped during the pre-aging method in a clamping apparatus exerting a clamping force thereon, wherein the clamping apparatus has a clamping geometry surrounding the process seal clamped therein, which is essentially identical to the clamping geometry surrounding the process seal in the pressure sensor.