Inline Poppet Valves for Industrial Pneumatic Applications

ROSS 27 Series directional control valves utilize proven poppet design technology that delivers exceptional performance in harsh industrial environments. Unlike spool valves that rely on close tolerances and sliding seals, poppet construction provides superior dirt tolerance, near-zero leakage, and positive sealing without sliding action that causes wear over time.

The inline mounting configuration allows installation close to pneumatic actuators, reducing the length of pipe that must be pressurized and exhausted during each machine cycle. This proximity improves response times, reduces air consumption, and enhances overall system efficiency.

ROSS poppet valves deliver consistent response times over the entire service life, eliminating the performance degradation common with competitive technologies. Field-proven in over 100,000 installations worldwide, these directional control valves provide the reliability plant managers demand for zero unplanned downtime.

Safety-Certified Directional Control Solutions

Safety integrity is fundamental to the 27 Series design philosophy. These directional control valves are certified by TÜV Rheinland in accordance with the most demanding international safety standards: 

• IEC 61508 and IEC 61511: Safety Integrity Level 2 (SIL 2) for singular applications with HFT = 0
• IEC 61508 and IEC 61511: Safety Integrity Level 3 (SIL 3) for redundant applications with HFT ≥1
• EN ISO 13849-1: Performance Level c (PL c) for singular applications with application-specific diagnosis
• EN ISO 13849-1: Performance Level e (PL e) for redundant applications with HFT ≥1

These certifications make ROSS 27 Series valves the proven choice for safety-critical machine control applications including lockout/tagout (LOTO) systems, safe exhaust functions, emergency stop circuits, and press control safety systems. Safety managers trust these valves to protect workers and ensure OSHA compliance in demanding manufacturing environments.

Available Valve Configurations

The 27 Series Classic product line offers three primary valve function categories to address diverse pneumatic control requirements: 

• 2/2 Valves (2-Way, 2-Position)
  Two-port, two-position valves available in normally closed and normally open configurations. These valves provide simple on/off control of pneumatic circuits with flow capacities from 1.8 Cv (1,800 Nl/min) up to 66 Cv (65,000 Nl/min). Body sizes range from 3/8" through 2-1/2" with port sizes from 1/4" to 2-1/2".
• 3/2 Valves (3-Way, 2-Position)
  Three-port, two-position valves offering normally closed and normally open functions. These directional control valves enable pressure supply, exhaust, and actuator control from a single valve body. Flow capacities reach up to 82 Cv (81,000 Nl/min) with the same body and port size ranges as 2/2 configurations. 
• 4/2 Valves (4-Way, 2-Position)
  Four-port, two-position valves designed for double-acting cylinder control and reversing applications. Maximum flow capacity reaches 34 Cv (33,000 Nl/min) with body sizes from 3/8" to 1-1/2".Actuation Options

ROSS 27 Series valves are available with three actuation technologies, each optimized for specific application requirements: 

• Solenoid Pilot Controlled Valves
  These valves combine the high shifting force of pneumatic pilot actuation with the control precision of electrical solenoids. Available DC (24V) and AC (110-120V, 230-240V) voltage options support integration with standard industrial control systems. Internal or external pilot supply configurations provide application flexibility. Solenoid pilot valves include non-locking manual override for maintenance and testing. 
• Direct Double Solenoid Controlled Valves
  Featuring dual solenoid actuation for positive control in both directions, these valves eliminate dependency on spring return mechanisms. This technology is ideal for applications requiring verified position control and fail-safe operation. Non-locking manual overrides are standard on both solenoids. 
• Pressure Controlled Valves
  Pneumatically actuated valves that shift based on pilot pressure signals. These valves are optimal for sequential control logic, cascade circuits, and applications where electrical signals are impractical or prohibited. The all-pneumatic design is inherently explosion-proof for hazardous location installations. 
   

Port Sizes and Flow Capacities

The 27 Series accommodates a comprehensive range of pneumatic flow requirements with nine body sizes and corresponding port configurations: 

• Body sizes: 3/8", 3/4", 1-1/4", 2" (standard sizes shown in catalog)
• Port sizes: 1/4" through 2-1/2" depending on body size and valve function
• Flow capacity range: 1.8 Cv to 71 Cv (1,800 to 70,000 Nl/min)
• Port thread options: NPT (standard) or G thread (ISO metric)

• Detailed flow specifications, Cv ratings, and valve response constants for each model are provided in the downloadable catalog, enabling precise system design and performance calculations. 
   

Technical Specifications and Operating Conditions

Operating Pressure Ranges: 

• Body sizes 3/8" through 1-1/4": 15 to 150 psig (1 to 10 bar)
• Body size 2": 30 to 150 psig (2 to 10 bar)
   

Temperature Ranges: 

• Solenoid pilot controlled ambient: 40° to 120°F (4° to 50°C)
• Solenoid pilot controlled media: 40° to 175°F (4° to 80°C)
• Pressure controlled ambient and media: 40° to 175°F (4° to 80°C)
   

Construction Materials: 

• Valve body: Cast aluminum for lightweight durability
• Poppet: Acetal and stainless steel for corrosion resistance
• Seals: Buna-N elastomers (alternative seal materials available for special applications)
   

Electrical Specifications for Solenoid Valves: 

• DC: 24 volts, 14 watts power consumption
• AC: 110-120V or 230-240V, 50/60 Hz, 87 VA inrush / 30 VA holding
• Rated for continuous duty operation
   

Applications and Industry Solutions

ROSS 27 Series directional control valves are engineered for the most demanding industrial environments:

• Metal forming and press applications: Safety control for mechanical power presses, hydraulic presses, and stamping operations
• Automotive manufacturing: Assembly line automation, paint booth controls, and material handling systems
• Packaging machinery: High-speed filling, capping, and labeling equipment
• Glass manufacturing: Mold actuation and handling systems in extreme temperature environments
• General industrial automation: Machine tool control, robotics, and process equipment

• The catalog includes specific application examples, recommended configurations, and integration guidance for common industrial scenarios.
   

Model Number Configuration and Selection

The comprehensive model number configurator detailed in the catalog enables precise valve specification. Engineers can systematically select: 

• Series designation (27)
• Revision level
• Actuation type (solenoid pilot, direct solenoid, pressure control)
• Valve function (2/2, 3/2, 4/2)
• Port thread type (NPT or G)
• Body and port sizes
• Pilot supply (internal or external)
• Electrical specifications (voltage and current)

• This structured approach ensures accurate ordering and reduces specification errors that can delay projects and increase costs.
   

Dimensional Drawings and CAD Resources

Complete dimensional drawings for all body sizes are provided in the catalog, showing critical mounting dimensions, port locations, electrical connections, and clearance requirements. Measurements are shown in both inches and millimeters to support global engineering standards.

Downloadable CAD models are available for all 27 Series configurations, supporting major CAD platforms and enabling seamless integration into machine designs. These precision 3D models accelerate the design process and ensure proper fitment before physical prototyping.

Accessories and System Components

The catalog details essential accessories that complete pneumatic system installations: 

• Exhaust silencers: Aluminum construction with flow capacities matched to valve exhaust ports
• Manual override kits: Flush button, extended button, and locking extended button options
• Indicator light kits: Visual verification of solenoid energization for troubleshooting
• Female silencer connectors: Hex nipples for flexible exhaust piping
   

Installation, Safety, and Maintenance Guidelines

Comprehensive installation and safety guidance is included to ensure proper valve performance and regulatory compliance. Critical topics covered include: 

• Pre-installation safety procedures and lockout/tagout requirements (OSHA 1910.147, EN 1037)
• Filtration requirements and air quality standards
• Proper mounting orientation and environmental considerations
• Electrical wiring specifications and hazardous location considerations
• Lubrication compatibility and fluid power system maintenance
   

Download Complete Catalog and CAD Models

Access the full technical catalog to review detailed specifications, performance data, ordering information, and application guidance. This comprehensive resource provides everything design engineers, safety managers, and maintenance professionals need to specify, install, and maintain ROSS 27 Series directional control valves.

Download includes:

• Complete product specifications and performance curves
• Model number configurator and ordering guides
• Dimensional drawings for all body sizes
• Installation and maintenance instructions
• Safety certification documentation
• Links to downloadable CAD models in multiple formats