Superior Poppet Valve Technology for Industrial Pneumatics

ROSS 27 Series valves feature poppet construction that provides exceptional dirt tolerance, near-zero leakage, and consistent response times throughout the valve's operational lifetime. The poppet design eliminates sliding action, preventing wear and damage while ensuring positive sealing even in contaminated air systems.

Available in 2/2, 3/2, and 4/2 valve configurations, the 27 Series offers comprehensive directional control functionality with port sizes ranging from 1/4" to 1-1/2". This extensive range accommodates flow rates up to 34 Cv (33,000 Nl/min), making these valves suitable for both precision control and high-volume applications.

SIL 2 Safety Certification for Critical Applications

The 27 Series valves are certified by TÜV Rheinland to Safety Integrity Level 2 (SIL 2) in accordance with IEC 61508 and IEC 61511 standards. This certification validates their use in safety instrumented systems where functional safety is paramount. In redundant applications with Hardware Fault Tolerance (HFT) ≥1, these valves can achieve SIL 3 and Performance Level (PL) e ratings.

The valves also comply with EN ISO 13849-1 standards, achieving PL c in singular applications with application-specific diagnosis. This makes them ideal for manufacturing environments requiring compliance with modern safety regulations including OSHA and ISO 14118.

Intelligent Logicair® Adaptor Technology

What distinguishes the 27 Series is the Logicair® adaptor system, which provides specialized pneumatic control functions without requiring additional electrical components:

Pressure Booster Adaptor increases actuating force on the valve piston, enabling reliable operation with low pilot pressures as low as 15 psig (1 bar). This adaptor is essential when inlet pressure exceeds available signal pressure or when using external pilot supplies with lower pressure than the inlet.

Air Index Adaptor transforms a single control valve into an impulse-controlled, mechanically detented valve. Successive momentary signals from the same pneumatic source actuate and deactivate the valve, providing memory function without electrical power.

Timed Sequence Adaptors allow precise control of actuation and deactivation delays up to 30 seconds for 2/2 valves and up to 3 seconds for 3/2 and 4/2 configurations. These adaptors feature continuously adjustable tapered needles for exact timing control.

Timed Sequence Extension Adaptors extend delay intervals up to 60 seconds while providing "snap action" by preventing piston creep. The extension adaptor keeps pilot air off the main valve piston until pressure builds sufficiently for prompt valve response.

Timed In/Out Sequence Adaptors provide independent control of both actuation and deactivation timing, offering maximum flexibility for complex pneumatic sequences.

Inlet Port Controlled Adaptors enable valve control based on inlet port pressure, creating automatic timing sequences that respond to system pressure conditions.

Dual Actuation Options: Solenoid and Pneumatic

The 27 Series is available in both solenoid pilot controlled and pressure controlled versions:

Solenoid Pilot Controlled valves feature electrical actuation with multiple voltage options including 24V DC, 110-120V AC, and 230-240V AC. Power consumption is optimized at 14 watts for DC models and 87 VA inrush/30 VA holding for AC versions. All solenoid valves include flush rubber manual overrides for emergency operation.

Pressure Controlled valves use pneumatic signals for actuation, ideal for explosion-proof environments or applications where electrical components must be minimized. These valves operate reliably across pressure ranges from 15 to 150 psig (1 to 10 bar) depending on adaptor configuration.

Robust Construction for Harsh Environments

Built with cast aluminum bodies, acetal and stainless steel poppets, and Buna-N seals, the 27 Series withstands demanding industrial conditions. Temperature ratings accommodate ambient conditions from 40° to 120°F (4° to 50°C) for solenoid models and 40° to 175°F (4° to 80°C) for pressure-controlled versions, with media temperatures up to 175°F (80°C).

The inline mounting design allows installation close to actuators, reducing the length of piping that must be pressurized or exhausted during each cycle. This configuration minimizes response time and improves energy efficiency while simplifying system layouts.

Valves can be mounted in any orientation, with vertical positioning preferred for optimal performance. Connection options include both NPT and G (ISO) thread types across all port sizes.

Comprehensive Flow Performance Data

The catalog provides detailed flow coefficient (Cv) values and response time constants for precise system design. Response times are calculated using the formula: Response Time (msec) = M + (F × V), where V represents volume in cubic inches to be filled to 90% of supply pressure or exhausted to 10% of supply pressure.

For example, a 3/4" body size with 1/2" inlet/outlet ports delivers flow rates of 6.2 Cv (6,100 Nl/min) in the 1-2 direction and 9.4 Cv (9,300 Nl/min) in the 2-3 direction for normally closed 3/2 configurations. The M constant of 11 and F constants of 0.43 and 0.27 enable accurate prediction of valve response in specific applications.

Extensive Model Number Configurator

The catalog includes a comprehensive model number configurator system that enables precise specification of valve requirements. The configuration code includes:

• Series designation (27)
• Adaptor type (pressure booster, air index, timed sequence, etc.)
• Valve function (2/2, 3/2, or 4/2)
• Port thread type (NPT or G)
• Actuation method (solenoid or pneumatic)
• Body size and port configuration
• Current type and voltage for solenoid models 

This systematic approach ensures accurate ordering and reduces the risk of specification errors that could delay projects or compromise system performance.

Application-Specific Solutions

The 27 Series Logicair® valves excel in applications requiring:

Load Holding and Position Control using pilot operated check valve configurations that trap pressure to maintain cylinder position during power loss or safety events.

Sequential Pneumatic Operations where timed actuation of multiple actuators must be coordinated without complex electrical control systems.

Low-Pressure Pilot Systems benefiting from pressure booster adaptors that enable reliable switching with minimal signal pressure.

Energy Isolation and Lockout/Tagout compliance through integration with ROSS L-O-X® (lockout and exhaust) systems for safe maintenance procedures.

Press Safety Systems where double valve technology and redundant configurations provide protection in metal forming applications.

Harsh Environment Control including glass manufacturing, automotive production, and metals processing where dirt tolerance and temperature resistance are critical.

Integration with ROSS Safety Systems

The 27 Series integrates seamlessly with ROSS Control Reliable Double Valve systems and SV27 Series sensing valves to create complete safety solutions meeting Category 2, 3, and 4 requirements under EN ISO 13849-1. These configurations provide position sensing, force-guided contacts, and redundant valve operation for the highest levels of machine safety.

Technical Support and Engineering Resources

This comprehensive catalog provides:

• Detailed valve schematics and pneumatic symbols for all configurations 
• Complete dimensional drawings for system integration 
• Installation and maintenance guidelines 
• Model-specific technical data sheets 
• Downloadable CAD models for design workflows 
• Flow performance curves and response time calculations 

Global Standards Compliance

Beyond SIL 2 certification, the 27 Series meets multiple international standards including CE marking, EAC declaration, and CSA/UL certification where applicable. This global compliance simplifies equipment export and ensures compatibility with diverse regional safety requirements.

The valves demonstrate conformity with IEC 61508, IEC 61511, EN ISO 13849-1, and OSHA requirements, providing documentation necessary for machine conformity assessments and risk reduction validation.

Superior Reliability and Long Service Life

ROSS 27 Series valves are engineered for consistent response times over the life of the valve, eliminating the degradation common in sliding spool designs. The poppet construction is self-cleaning and wear-compensating, maintaining performance even in contaminated air systems.

Field-convertible pilot supply options allow easy switching between internal and external pilot configurations without replacing the valve, providing flexibility as system requirements evolve.

The combination of robust materials, proven poppet technology, and intelligent air logic creates a valve platform that delivers reliable performance across millions of cycles in the most demanding industrial environments.