The DSTI SPS Series (Single Passage Standard) Rotary Unions, engineered and manufactured by Dynamic Sealing Technologies, Inc. (DSTI - USA), deliver a compact, lightweight, and highly reliable dynamic fluid sealing solution for transferring air, gas, and vacuum media between stationary piping and continuously rotating machine assemblies.

The SPS Series is thoughtfully scaled across 4 primary configurations covering standard industrial NPT thread sizes from 1/4" up to 2":
1. Model SPS-5210: Features a 1/4"-18 NPT connection with a 0.250" [6.35 mm] passage size, housed in an ultra-compact 1.500" [38.1 mm] outer diameter body with an exceptionally low minimum torque of 1 in-lbs [0.11 Nm], perfectly suited for compact robotics and small pneumatic actuators.
2. Model SPS-5410: Features a 1/2"-14 NPT connection with a 0.500" [12.7 mm] passage size, offering an optimal balance between envelope dimensions and pneumatic flow volume for rotary index tables, air reels, and packaging machines.
3. Model SPS-5610: Features a 1"-11.5 NPT connection with a 1.000" [25.4 mm] passage size, facilitating high-capacity air delivery and exhaust for heavy industrial reels, rotating drums, and large pneumatic clutches.
4. Model SPS-5910: Features a 2"-11.5 NPT connection with a generous 2.000" [50.8 mm] passage size, purpose-engineered for high-volume vacuum transfer, primary plant air feeds, and heavy-duty rotary chambers.

Key Engineering Highlights & Operational Benefits:
- Corrosion-Resistant Hybrid Metal Architecture: The union features an exterior housing precision-machined from high-strength aluminum with a Black Hardcoat Anodized finish, providing excellent chemical resilience, scratch protection, and low overall weight. The rotating shaft is constructed from corrosion-proof 304 Stainless Steel, ensuring long-term structural integrity and optimal dynamic sealing contact surfaces.
- Ultra-Low Rotational Torque: Equipped with DSTI’s proprietary PTFE-based elastomeric low-friction dynamic seals and dual pre-lubricated precision ball bearings, operating torque ranges from just 0.11 Nm to 0.45 Nm. This drastically minimizes mechanical drive strain, eliminates frictional heat buildup, and prolongs component operational life.
- Simple, Rigid Mechanical Mounting: Standardized with an external male NPT threaded shaft for direct threading into the machine's rotating hub, a female NPT threaded housing port for stationary hose plumbing, and two tapped holes on the housing end-face for an anti-rotation restraint bracket.
- Seamless Slip Ring Integration: Engineered to integrate directly with standard DSTI through-bore electrical slip rings, enabling a combined fluid and electrical solution for transferring power, sensor feedback, and real-time industrial Ethernet/Fieldbus communication.

Typical Industrial Applications:
- Automatic pneumatic hose reels and umbilical cable reeling equipment.
- Rotary indexing tables, pneumatic workholding chucks, and multi-axis CNC machine fixtures.
- High-speed robotic Pick & Place vacuum transfer heads and rotary labeling machinery.
- Packaging automation, film converting lines, and semiconductor processing equipment.

• Manufacturer: DSTI (Dynamic Sealing Technologies, Inc.)
• Origin / Country of Manufacture: USA
• Product Line: SPS Series Single-Passage Rotary Unions & Joints
• Models Covered: SPS-5210, SPS-5410, SPS-5610, SPS-5910
• Number of Flow Passages: 1 Independent Flow Passage
• Individual Model Specifications:
  + Model SPS-5210:
    - Thread Connection: 1/4"-18 NPT (Male shaft / Female housing)
    - Flow Passage Size: 0.250" [6.35 mm]
    - Outer Diameter: 1.500" [38.1 mm]
    - Overall Length: 2.380" [60.45 mm]
    - Minimum Rotational Torque: 1 in-lbs [0.11 Nm]
  + Model SPS-5410:
    - Thread Connection: 1/2"-14 NPT (Male shaft / Female housing)
    - Flow Passage Size: 0.500" [12.7 mm]
    - Outer Diameter: 1.750" [44.45 mm]
    - Overall Length: 2.630" [66.80 mm]
    - Minimum Rotational Torque: 2 in-lbs [0.23 Nm]
  + Model SPS-5610:
    - Thread Connection: 1"-11.5 NPT (Male shaft / Female housing)
    - Flow Passage Size: 1.000" [25.4 mm]
    - Outer Diameter: 2.750" [69.85 mm]
    - Overall Length: 3.130" [79.50 mm]
    - Minimum Rotational Torque: 3 in-lbs [0.34 Nm]
  + Model SPS-5910:
    - Thread Connection: 2"-11.5 NPT (Male shaft / Female housing)
    - Flow Passage Size: 2.000" [50.8 mm]
    - Outer Diameter: 3.940" [100.08 mm]
    - Overall Length: 3.690" [93.73 mm]
    - Minimum Rotational Torque: 4 in-lbs [0.45 Nm]
• Maximum Operating Pressure: 600 PSI [40 BAR]
• Maximum Vacuum Rating: 30 in. Hg
• Maximum Rotational Speed: 500 RPM
• Operating Temperature Range: -18°C to 105°C [0°F to 220°F]
• Compatible Fluid Media: Compressed Air, Industrial Vacuum, Inert Gases (Nitrogen, Argon, etc.)
• Housing Material: Black Hardcoat Anodized Aluminum
• Shaft Material: 304 Stainless Steel
• Dynamic Sealing: DSTI proprietary low-torque PTFE elastomeric seals
• Bearing Support: Dual high-precision sealed deep-groove ball bearings
• Electrical Integration: Compatible for direct integration with DSTI through-bore slip ring modules.