2S Series Direct-Acting Normally Closed
More Than "Good Enough": Why the 2S Stainless Series is the Ultimate Platform for Fluid Challenges
In fluid control, many designers fall into the "MOPD Trap." By defaulting to standard pilot-operated valves for cost or familiarity, they encounter critical failures in gravity-fed tanks or vacuum lines. Pilot valves are pressure-assisted; without a Minimum Operating Pressure Differential, they simply will not actuate.
The AirTAC 2S Series Stainless Solenoid Valve is the engineered escape from this trap. By utilizing a Direct-Acting architecture, it operates with absolute independence from system pressure. It isn't just a single valve; it is a versatile technical platform ranging from deep vacuum service to 450 psi high-pressure surges.
- True Zero-MOPD Performance: The coil provides 100% of the mechanical muscle. Reliable actuation at absolute 0 psi.
- Chemical Armor: Standardized with a SUS304 Stainless Steel body and FPM (Viton) seals for elite resistance to oils, fuels, and weak acids.
- Application Versatility: The definitive choice for Vacuum Pick-and-Place and Gravity-Fed Drainage.
- Mechanical Reliability: IP65 rated with modular DIN connectors or compact flying leads to suit varied OEM environments.
1. Mechanical Logic: The Direct-Acting Architecture
The 2S Series mechanism relies on a high-torque electromagnetic field to physically lift a plunger against a static spring and fluid load. This relationship is governed by a fundamental force-balance:
$$Force_{Coil} > Force_{Spring} + (Pressure \times Area_{Orifice})$$
In this Normally Closed (NC) configuration, the coil must overcome the product of the inlet pressure and the orifice area. This physics-driven design ensures that the valve does not require the "helper" pressure typical of piloted valves, allowing it to function flawlessly in low-pressure loops and vacuum lines.
2. Industrial Standard: SUS304 + FPM-F
Durability in harsh environments is a function of the material interface. AirTAC standardizes the 2S series on a professional-grade material stack:
SUS304 Structural Defense
Provides superior corrosion resistance compared to brass. Essential for deionized water, food-grade applications, and environments prone to oxidation.
FPM-F (Viton) Seals
Unlike standard NBR, FPM-F maintains seal integrity when exposed to petroleum fuels and high temperatures (up to 90°C media temp).
3. The Scaling Matrix: Selecting Your Performance Curve
The 2S family allows engineers to balance Orifice Area (Flow) against Static Pressure (P) within the same physical footprint:
2SX "Pressure Warriors"
Utilizes a tiny 1.5mm orifice to handle staggering pressures up to 3.0 MPa (450 psi). Ideal for hydraulic pilots or gas compressors.
2S "Standard Workhorse"
A balanced 5.0mm orifice providing 0.83 Cv at 1.0 MPa (150 psi). The mainstream choice for general automation.
2ST "Flow Experts"
Features a massive 10.0mm orifice for high-volume 2.20 Cv throughput, restricted to low-pressure drainage tasks (15 psi).
Technical FAQ
Can this be used for Vacuum?
Absolutely. Vacuum is the "kill zone" for pilot valves. The 2S's direct-acting plunger doesn't care about atmospheric pressure; it opens and closes based purely on magnetic force.
DIN vs. Flying Leads?
DIN is the maintainer's choice—allowing a 30-second coil swap without an electrician. Flying leads are the OEM's choice for compact, hard-wired, high-volume production builds.
Certainty in a World of Variables
The AirTAC 2S Series Stainless Direct-Acting Valve is more than a component; it is a system-level solution for the industrial "extreme." By eliminating the failure modes of pilot assistance and standardizing on SUS304 + Viton armor, it ensures that your most challenging fluid loops—whether at a deep vacuum or 450 psi—simply perform as designed.