Description

Elevator Door Knife CV600 / CV620 – Usage, Replacement Cycle & Maintenance Guide
by Nanjing Zhuye Elevatorparts

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Introduction
The CV600 / CV620 door knife is the critical mechanical interface that unlocks landing doors and ensures smooth door motion. Manufactured and distributed worldwide by Nanjing Zhuye Elevatorparts, this precision-machined component meets EN 81-20/50 and ASME A17.1 standards, delivering 1 million+ cycles of reliable, low-noise operation. This 800-word guide covers correct installation, daily maintenance, and the recommended replacement cycle to keep every elevator door safe, smooth, and code-compliant.

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1. Product Highlights
– Material: 304 stainless steel, precision-machined
– Hardness: 45 HRC, salt-spray 500 h
– Tolerance: ±0.02 mm on all critical surfaces
– Weight: 0.35 kg (CV600), 0.42 kg (CV620)
– Mechanical Life: 1 million+ door cycles

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2. Installation Method
Step 1 – Preparation
De-energise the door drive; lock-out/tag-out and verify zero energy. Record serial number and model (CV600 or CV620).

**Step 2 – Removal**
Remove door operator cover; extract split pins and slide worn knife off the shaft. Clean shaft with 70 % IPA and inspect for scoring.

Step 3 – Fitting New Knife
Slide CV600/CV620 onto shaft until flush. Insert new split pins; torque M6 screws to 8 N·m. Ensure knife is perpendicular to track (±0.5 mm).

Step 4 – Commissioning
Run door at inspection speed (0.3 m/s) for 10 cycles. Check lateral play <0.3 mm, temperature rise <45 °C, no squeaks.

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3. Daily & Preventive Maintenance
Daily (Technician)
Visual check – knife straight, no cracks, grease present.

Monthly
Wipe knife and track with lint-free cloth; remove dust and oil build-up.

Quarterly
Measure knife thickness with caliper; record wear rate. Check split-pin tightness and track alignment.

Annually
Replace grease pack and torque screws. Full dimensional audit and torque re-check.

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4. Replacement Cycle & Indicators
| Duty Cycle | Replace Every | Cycles | Warning Signs |
| Standard residential | 5–7 years | 1 M | Thickness <90 %, >65 dB noise |
| Commercial / hospital | 3–4 years | 0.6 M | Blue heat spots, vibration >2 g |
| High-speed / freight | 2–3 years | 0.4 M | Track scoring, temp >70 °C |

Replace immediately if:
– Thickness <90 % of original
– Cracks, pitting, or deformation
– Repeated “door unlock fault” without mis-alignment
– Temperature rise >70 °C during normal run

Maintain one spare **CV600 / CV620** per 25 doors for <4-hour response.

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5. Why Choose Nanjing Zhuye Elevatorparts?
• Full traceability – laser-etched serial & QR code
• Same-day global dispatch via DHL/FedEx Express
• 24/7 multilingual hotline and on-site training
• Competitive tiered pricing and custom hardness for OEM projects

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6. Conclusion
The CV600 / CV620 door knife is small but mission-critical. By following the installation, testing, and replacement guidelines—and sourcing only from Nanjing Zhuye Elevatorparts—you guarantee code compliance, reduce downtime, and ensure every passenger enters and exits smoothly.