Rod End Bearing SA...E / SA...ES / SA...ES-2RS FAQ

1. What do the suffixes E, ES, and ES-2RS mean?

Q1: What is the complete model structure of SA series rod ends?

• SA: Male thread rod end (right-hand; left-hand is prefixed with L, e.g., SAL).
• Suffix priority: -2RS (Sealing) > ES (Lubrication Feature) > E (Basic Structure). More suffixes = more comprehensive functions.

Q2: What are the key differences between SA...E, SA...ES, and SA...ES-2RS?

Q3: How to interpret the numbers in the model (e.g., SA20 E, SA25 ES-2RS)?

• Bore < 10mm: Exact size (e.g., SA8 E = 8mm bore).
• Bore ≥ 500mm: Use "/" separator (e.g., SA/500 ES).
• Optional suffixes: C = PTFE-coated bronze sliding surface (maintenance-free); can be combined with E/ES/ES-2RS (e.g., SA20 C ES-2RS).

2. Selection Guide: Which One to Choose?

Q4: What are the application scenarios for each type?

1. SA...E: Low-cost, basic type.
   • ✅ Dry, clean, low-speed (≤ 500 rpm), low-load equipment.
   • ❌ Requires relubrication every 1–3 months (disassembly needed).
    
2. SA...ES: Relubrication-friendly type.
   • ✅ High-load, medium/high-speed (≤ 1500 rpm) machinery (e.g., machine tool links).
   • ✅ Relubricate via grease fitting every 6–12 months (no disassembly).
    
3. SA...ES-2RS: Sealed & relubrication type.
   • ✅ Wet, dusty, outdoor, or corrosive environments (e.g., mining equipment).
   • ✅ Long maintenance cycle (1–2 years); waterproof splash (not full immersion).
    

Q5: Do SA...ES-2RS bearings prevent water ingress?

• Double lips create a tight seal against the inner ring to block water, dust, and contaminants.
• For underwater or high-pressure spray conditions, add an additional waterproof cover.

Q6: Are there differences in load capacity between the three types?

• The ES/ES-2RS design optimizes lubrication grooves to reduce friction loss.
• The ES-2RS seal does NOT affect radial/axial load transmission (axial load ≤ 20% of radial load).

3. Installation & Maintenance: Practical Guidelines

Q7: What are the critical installation rules?

1. Press the outer ring into the housing using a press or sleeve (never hit the thread or inner ring).
2. Ensure the rod end swings freely with no sticking.
3. Preload: Leave a small clearance (0.1–0.3mm) to prevent overheating and seizing.
4. Do NOT mix components from different bore sizes (e.g., SA20 outer ring + SA25 inner ring).

Q8: What grease should be used? What is the relubrication cycle?

• General use: Lithium-based grease (-20°C ~ 120°C).
• High temp (>120°C): Complex lithium grease.
• Wet environment: Water-resistant lithium grease.

• SA...E: Every 1–3 months.
• SA...ES: Every 6–12 months (fill 1/3–1/2 of the bearing’s internal volume each time).
• SA...ES-2RS: Every 1–2 years (drain old grease before adding new).

Q9: Can the ES-2RS seal be replaced? How?

1. Gently pry out the old seal (avoid scratching the groove).
2. Clean the groove of old grease and debris.
3. Apply a thin layer of grease to the new seal (reduce friction).
4. Press the new seal evenly into the groove (ensure lips are aligned and tight against the inner ring).

• Note: Match seal material to 工况 (FKM for high temp, NBR for low temp).

4. Troubleshooting: Common Issues & Solutions

Q10: Bearing overheats (temperature > 80°C)?

1. Over-preload: Too small internal clearance → disassemble and readjust.
2. Grease issues: Overfilling (poor heat dissipation) → drain excess; wrong type → replace with matching grease.
3. Seal friction (ES-2RS): Misaligned seal → check and replace with correct size.

Q11: Noise, sticking, or surface peeling?

• Noise/sticking: Lack of grease (SA...E: clean and relubricate; ES/ES-2RS: relubricate via fitting) or contamination (open-type E: severe cases need replacement).
• Surface peeling: Overload (upgrade to larger bore/higher load rating) or installation damage (replace and 规范 installation).

Q12: Grease fitting is blocked. How to fix it?

1. Mild blockage: Use a fine wire to unclog the channel; flush with a small amount of kerosene; then add grease.
2. Severe blockage: Replace the grease fitting (use a matching size to avoid thread damage).

5. Business & Procurement FAQs

Q13: Are SA...E/ES/ES-2RS interchangeable with international brands (e.g., SKF)?

• The SA series is designed to match international standards (GB/T 304 / ISO 12240-1).
• For critical applications, confirm load rating, speed rating, and seal material to avoid mismatches.

Q14: What is the lead time for bulk orders?

• Urgent orders (≤ 7 days) are available for standard sizes with additional express fees.

Q15: Do you provide sample testing before bulk order?

• Free samples for standard sizes (shipping fee applies).
• Third-party testing (e.g., dimensional accuracy, load test) is available upon request.