U Type Rod End Bearing Fish Eye Joint

U Type Rod End Bearing Fish Eye Joint | 360° Universal Articulated Fitting for Cylinder Rod End

Brand: SOLH by Richge Technology | Pneumatic Cylinder Piston Rod Universal Rod End Bearing

1. Product Overview

     U-type fish eye joint, also known as rod end spherical bearing with suffix U, is a 360° universal articulated accessory mounted on cylinder piston rod. It solves misalignment and multi-direction swing problems and eliminates lateral force, compatible with SC, MA, MAL and other standard pneumatic cylinders.

2. Structure & Core Functions

     • Structure: Female thread (connect piston rod) + spherical ball bearing + outer ring, free radial and angular swing.

     • Swing Capacity: ±13°~±15° universal swing, much larger than ±5° of I/Y clevis fittings for multi-direction adaptive adjustment.

     • Material Options

￮ Standard: Bearing steel / carbon steel, surface quenched with black oxide or galvanized finish

￮ Wear-resistant: Copper alloy bushing / self-lubricating type

￮ Anti-corrosion: 304 stainless steel

     • Core Benefits

￮ Compensate coaxial deviation up to 2mm and angular deviation up to 15°

￮ Prevent bending moment and lateral force on piston rod, protect cylinder seals

￮ Ideal for high-speed, high-frequency and eccentric load working conditions

3. Model Naming Convention for Mainstream Brands

  1) AirTAC (widely adopted)

     Format: F-M thread × pitch U
     Definition: F = accessory; M = thread specification; U = fish eye rod end bearing

     • F-M8×1.25U for 25mm bore cylinder

     • F-M10×1.25U for 32mm bore cylinder

     • F-M12×1.25U for 40mm bore cylinder

     • F-M16×1.5U for 50/63mm bore cylinder

     • F-M20×1.5U for 80/100mm bore cylinder

  2) SMC PHS Series: Format: PHS-thread, example: PHS-10

  3) General domestic marking: SI/M12×1.25 (female thread), SA/M12×1.25 (male thread)

4. Common Specification & Cylinder Bore Matching Chart

5. Comparison: U-type Fish Eye vs I/Y Clevis / F Floating Joint

  Selection Guide: Large eccentricity & multi-direction swing → U-type; Misalignment & high frequency action → F-type; Low speed heavy load → Y-type; Double ear load bracket → I-type.

6. Installation Guidelines

  1. Screw female thread onto piston rod external thread, apply anaerobic thread locker and control tightening torque properly.

  2. Mount outer ring hole to load pin shaft. Strict coaxial alignment is not required and certain eccentricity is permitted.

  3. Working pressure: ≤1.0MPa for standard cylinders; operating temperature: -20℃ ~ +120℃.

  4. Suitable for push-pull dynamic load and high-frequency operation in limited installation space. Not for continuous pure rotary motion.

7. Typical Application Scenarios

     •  Automation equipment, 3C electronics, robot grippers

     • High-speed conveying, stamping & press-fitting, long-stroke mechanisms

     • Equipment with poor coaxiality, heavy vibration and eccentric load