Critical Technical Advantages
Forged Valve Body Design: To ensure maximum structural integrity and resistance to intergranular corrosion, the EHU features a forged body. This manufacturing process eliminates the porosity risks associated with casting, which is critical when handling ammonium carbamate.
One-Piece Plug and Stem: The valve plug and stem are machined from a single solid piece of material. By eliminating threaded joints, welds, and pins, the EHU removes common failure points where crevice corrosion typically starts in urea processes.
No Balance Seals: The EHU is an unbalanced design. By removing internal balance seals, the valve eliminates additional cavities and crevices that could harbor corrosive media or lead to premature seal failure in high-pressure urea synthesis loops.
Double ENVIRO-SEAL Packing: Utilizing a urea-specific version of the enhanced ENVIRO-SEAL live-loaded system, the EHU provides superior fugitive emission protection. The double packing set reduces abrasive wear from crystallized particles, while Belleville springs maintain consistent stress during intense thermal cycling.
Simple Trim Configuration: The internal trim uses metal-to-metal sealing joints and completely eliminates gaskets. This “gasketless” design significantly reduces the risk of crevice corrosion, which is a primary concern in carbamate service.
Maintenance-Friendly Top Entry: An optional removable bonnet and top-loaded plug allow for easy access to the packing and internal components. This top-entry capability simplifies service and reduces the time required for maintenance during plant turnarounds.
Advanced Thermal Management: The EHU is available with integrated body heat tracing and packing flushing connections. These features prevent the urea from crystallizing (setting up) within the valve or around the stem, ensuring continuous operation.
Technical Performance Matrix
| Feature | Details |
| Application | Urea and Ammonium Carbamate Service |
| Body Construction | Forged Specialty Alloys (e.g., 316L UG, Duplex) |
| Trim Style | Unbalanced, Gasketless Metal-to-Metal |
| Guiding | Heavy-Duty Stem Guiding |
| Packing | Double ENVIRO-SEAL (Live-loaded) |
| Specialized Features | Flushing Connections & Heat Tracing |
Primary Applications
High-Pressure Carbamate Condenser: Regulating the flow of highly corrosive carbamate solutions.
Urea Reactor Letdown: Precise pressure control of the urea synthesis mixture.
CO2 Stripper Level Control: Managing the liquid level in the stripping section of the urea plant.
Ammonia Feed Systems: Reliable modulation of high-pressure ammonia inputs.
