Body and Housing Materials
Stainless Steel Construction
The Yokogawa EJA130E Differential Pressure Transmitter primarily utilizes stainless steel for its body and housing construction. This choice of material is not arbitrary; stainless steel offers a combination of strength, corrosion resistance, and durability that is essential for industrial instrumentation. The most common grade used is 316L stainless steel, known for its exceptional resistance to chemical attack and its ability to withstand harsh environmental conditions. The use of 316L stainless steel in the EJA130E's body provides several advantages:
- Corrosion Resistance: It resists corrosion from a wide range of chemicals, making it suitable for use in diverse industrial processes.
- Temperature Stability: Stainless steel maintains its structural integrity across a broad temperature range, ensuring reliable performance in various operating conditions.
- Durability: The material's strength and toughness contribute to the transmitter's long service life, even in challenging industrial environments.
Sealing Materials
While the main body is constructed from stainless steel, the EJA130E incorporates various sealing materials to ensure its integrity and prevent leaks. These materials are carefully selected to complement the stainless steel construction and maintain the transmitter's performance under pressure and temperature variations. Common sealing materials used in the EJA130E include:
- Fluoroelastomers (FKM): Known for their excellent chemical resistance and temperature tolerance.
- Ethylene Propylene Diene Monomer (EPDM): Offers good resistance to water and steam.
- Perfluoroelastomers (FFKM): Provides superior chemical resistance for the most demanding applications.
Protective Coatings
In certain applications where additional protection is required, the EJA130E may feature specialized coatings applied to its stainless steel body. These coatings enhance the transmitter's resistance to specific environmental factors or process conditions. Examples of protective coatings include:
- PTFE (Polytetrafluoroethylene) Coating: Offers excellent chemical resistance and non-stick properties.
- Epoxy Coatings: Provide additional corrosion protection in highly aggressive environments.
- Nylon Coatings: Enhance impact resistance and provide electrical insulation.
Sensor and Diaphragm Materials
Silicon Resonant Sensor
At the heart of the Yokogawa EJA130E Differential Pressure Transmitter lies its innovative silicon resonant sensor. This sensor is fabricated from high-purity single-crystal silicon, chosen for its excellent mechanical properties and stability. The use of silicon allows for the creation of a highly sensitive and accurate sensing element that can detect minute pressure differences. Key characteristics of the silicon resonant sensor include:
- High Sensitivity: The silicon structure enables precise measurement of small pressure changes.
- Temperature Stability: Silicon's thermal properties contribute to consistent performance across varying temperatures.
- Long-term Stability: The inherent stability of silicon helps maintain calibration over extended periods.
Diaphragm Materials
The diaphragm is a critical component in the EJA130E, as it directly interfaces with the process fluid and translates pressure changes into measurable signals. Yokogawa employs different diaphragm materials to suit various process conditions and compatibility requirements. Common diaphragm materials in the EJA130E include:
- 316L Stainless Steel: Offers excellent corrosion resistance and is suitable for a wide range of applications.
- Hastelloy C-276: Provides superior resistance to highly corrosive environments, particularly those containing chlorides.
- Tantalum: Offers exceptional corrosion resistance, especially against strong acids.
- Monel: Suitable for applications involving seawater and other marine environments.
Fill Fluids
The space between the diaphragm and the silicon sensor is filled with a carefully selected fluid that transmits pressure changes from the process to the sensor. The choice of fill fluid can significantly impact the transmitter's performance in different temperature ranges and process conditions. Typical fill fluids used in the EJA130E include:
- Silicone Oil: Offers good performance across a wide temperature range.
- Fluorinated Oil: Provides excellent chemical compatibility and low temperature performance.
- Inert Fluids: Used in applications requiring high purity or oxygen service.
Electrical and Connection Components
Terminal Block Materials
The terminal block in the Yokogawa EJA130E Differential Pressure Transmitter serves as the interface for electrical connections. The materials used in its construction must provide excellent electrical insulation while withstanding environmental factors. Common materials used for the terminal block include:
- Glass-filled Polyamide: Offers good electrical insulation and mechanical strength.
- Polyphenylene Sulfide (PPS): Provides excellent chemical resistance and dimensional stability.
- Polybutylene Terephthalate (PBT): Known for its electrical insulating properties and resistance to heat and chemicals.
Cable Glands and Conduit Connections
The EJA130E features various options for cable entry and conduit connections, each utilizing materials suited to different installation requirements and environmental conditions. Materials commonly used in these components include:
- Nickel-plated Brass: Offers good corrosion resistance and durability.
- 316 Stainless Steel: Provides superior corrosion resistance for harsh environments.
- Polyamide: Used in plastic cable glands for lighter duty applications.
Display and Indicator Materials
For models equipped with local displays or indicators, the materials used must withstand environmental conditions while providing clear visibility. Typical materials for display components include:
- Tempered Glass: Used for the display window, offering strength and clarity.
- Liquid Crystal Display (LCD): Provides clear digital readouts with low power consumption.
- Polycarbonate: Sometimes used as an alternative to glass for the display cover, offering impact resistance.
Conclusion
The Yokogawa EJA130E Differential Pressure Transmitter's construction involves a careful selection of materials, each chosen for its specific properties and performance characteristics. From the stainless steel body to the silicon resonant sensor and specialized diaphragm materials, every component is designed to ensure accuracy, reliability, and longevity in diverse industrial applications. If you want to get more information about this product, you can contact us at lm@zyyinstrument.com.
