TOP-204HBR-VB NOP Trochoid Pump 4cc with Relief Valve

Product Overview

Nippon Oil Pump (NOP) TOP Series Trochoid® pumps (including models TOP-204HBR-VB, TOP-206HBR-VB, TOP-208HBR-VB, TOP-210HBR-VB, TOP-212HBR-VB and related configurations) are high-precision fixed-displacement internal-gear Trochoid pumps. Designed for smooth transfer of hydraulic, lubricating, and cooling oils, they offer low noise, high volumetric efficiency, and a compact footprint. The VB relief-valve versions provide overpressure protection. These pumps deliver exact drop-in interchangeability with original NOP units. Every unit undergoes 100% simulated operating-condition testing to ensure reliable performance and long service life—ideal for machine tools, industrial equipment, and lubrication systems.

Technical Specifications 

• Models: TOP-204HBR-VB / TOP-206HBR-VB / TOP-208HBR-VB / TOP-210HBR-VB / TOP-212HBR-VB (TOP-2HB Series with relief valve)
• Displacement: TOP-204HB = 4.0 cm³/rev; TOP-206HB = 6.0 cm³/rev; TOP-208HB = 8.0 cm³/rev; TOP-210HB = 10.0 cm³/rev; TOP-212HB = 12.0 cm³/rev
• Maximum (rated) pressure: TOP-204HB 3.0 MPa; TOP-206/208/210HB 2.5 MPa; TOP-212HB 2.0 MPa
• Peak pressure: per series rated values (test conditions ISO-VG46 oil at 40°C)
• Maximum speed: TOP-204HB up to 3000 min⁻¹; TOP-206/208/210HB up to 2500 min⁻¹; TOP-212HB up to 2000 min⁻¹
• Control type: Fixed displacement (quantitative) Trochoid internal-gear pump with VB-type relief valve
• Theoretical flow (at 1500/1800 min⁻¹): varies by displacement, e.g., TOP-204HB approx. 6.0 / 7.2 L/min
• Weight: approx. 3.6–4.3 kg (slightly higher with valve)
• Additional: Optional rotation direction, seal materials, and port types

(Data extracted from official Nippon Oil Pump Trochoid pump technical literature; actual performance depends on exact configuration and operating conditions.)

Key Technical Advantages

1. Precision-machined Trochoid rotor and stator deliver high volumetric efficiency, low-pulsation flow, and quiet, smooth operation.
2. Compact, lightweight design with excellent suction capability suits space-constrained machine tools and industrial lubrication systems.
3. Integrated VB relief valve provides reliable overpressure protection; multiple seal materials adapt to various fluids and temperatures.
4. 100% simulated-condition testing combined with true drop-in interchangeability ensures consistent performance and minimized downtime.

Application Areas

• Lubricating and cooling oil transfer on machine tools and machining centers
• Hydraulic oil circulation and filtration systems in industrial equipment
• Oil transfer and replenishment on small- to medium-sized machinery
• Other applications requiring low-noise, reliable fixed-displacement oil supply with overpressure protection

Expert Maintenance Tips

Use clean hydraulic or lubricating oil meeting the required viscosity (ISO-VG46 reference conditions). Avoid excessively low suction pressure that can cause cavitation. Ensure correct rotation direction and full system bleeding during installation. Periodically check relief-valve settings and seals. Do not exceed rated pressure or speed. Protect ports during storage to prevent contamination.