Product Overview
The ULVAC DA-121DD is a dry vacuum diaphragm pump engineered for oil-free evacuation and transfer duties in demanding industrial environments. Utilizing a reciprocating elastomeric diaphragm driven by a direct-coupled motor, this pump eliminates the need for sealing oil or lubricating fluids in the gas path, preventing backstreaming contamination and ensuring a clean vacuum supply. Its dual-stage configuration (designated by the “DD” suffix) delivers deeper ultimate vacuum than single-stage equivalents, making it suitable for backing turbomolecular pumps, roughing high-vacuum chambers, and supporting analytical instrumentation. The DA-121DD is a compact, chemically resistant solution for continuous-duty industrial vacuum service.
Technical Specifications
| Parameter | Specification / Feature |
|---|---|
| Component Type | Dry Vacuum Diaphragm Pump |
| Model Designation | DA-121DD |
| Operating Pressure | Vacuum service — ultimate vacuum to approx. 1.0 kPa (dual-stage) |
| Mounting & Connection | Standard ISO / Manufacturer Interface (flange or hose port) |
Engineering Features & Advantages
- Precision Performance: Dual-stage diaphragm mechanism delivers stable, deep vacuum with minimal pulsation and no oil contamination in the process stream.
- Industrial Reliability: Built for continuous operation under severe industrial conditions, with chemically resistant wetted materials and a thermally protected direct-drive motor.
- Direct Fit Replacement: Exact dimensional and functional compatibility with original OEM standards, allowing drop-in replacement without system modification.
Typical Industrial Applications
Commonly deployed in semiconductor and thin-film processing equipment, analytical and laboratory instrumentation, vacuum coating and metallurgical systems, and plastic injection molding or CNC machine tool vacuum clamping circuits where oil-free, clean evacuation is mandatory.
PRODUCT IMAGES

ULVAC DA-121DD Dry Vacuum Diaphragm Pump
âš¡ Emergency Plant Maintenance & Ready-to-Ship Notice:
- Authentic & Fully Tested: 100% bench tested for hydraulic response, pressure rating, and null-bias stability before dispatch.
- Fast Dispatch: In-stock units ready for same-day dispatch via DHL / FedEx Express directly to your plant.
- Pre-Shipment Verification: High-definition photos, video testing runs, and serial number verification provided prior to shipment.
- Peace of Mind: Covered by our 12-Month Replacement Warranty.
Shop the genuine ULVAC DA-121DD Vacuum Solenoid Valve. This Japan-made 24 VDC vacuum component features a 2-port direct-acting design, delivering leak-free, reliable vacuum control for heavy-duty industrial systems.