Single Phase (220V/50Hz) & Three Phase (380V/50Hz)
Internal Medium
Food-Grade, Non-Toxic Dielectric Cooling Oil
Protection Class
IP68
Insulation Class
Class B / Class F
Outer Shell Material
AISI 304 Stainless Steel Casing
Mounting Standard
Fully Compliant with NEMA Flange Standards
Oil Cooled Motor Construction Details
Food-grade dielectric oil filling – The motor is filled with non-toxic dielectric oil. Provides low-friction lubrication for bearings and transfers heat from windings to the outer shell.
Mechanical sealing system – Includes a mechanical seal and a sand guard. Prevents sand from entering the motor and stops oil leakage.
AISI 304 stainless steel jacket – The outer sleeve and shaft are made of AISI 304 stainless steel. Protects against hydrostatic pressure and corrosion.
NEMA standard mounting flange – Meets NEMA dimensional standards. Compatible with standard multi-stage pump ends worldwide.
Operating Limits & Installation
NF-O series motors operate within the following limits:
Max. Fluid Temperature: 35°C.
Minimum Cooling Flow: 0.16 m/s water velocity across motor surface
Voltage Tolerance: ±10% of rated voltage
Installation: Vertical or horizontal
Groundwater Extraction Applications
Borehole deep well pumping – Groundwater lifting from deep well casings for rural and community water supply.
Farm and field irrigation – For seasonal flooding, center-pivot irrigation, and greenhouse water networks.
Livestock water supply – Water delivery for ranching and livestock farming.
Engineering Insights & FAQ
What are the main advantages of an oil cooled motor compared to a water cooled one?
Oil-cooled motors use dielectric oil. The oil provides low-friction lubrication for bearings and protects copper windings from moisture.
Is the oil inside the motor safe if a leak occurs?
Yes. The NF-O series uses food-grade, non-toxic dielectric oil. It is safe for agricultural irrigation and well environments.
Do oil-cooled submersible motors need periodic oil changes?
No. NF-O series motors are sealed at the factory. Under normal operating limits, the dielectric oil does not degrade or need replacement. If the mechanical seals remain undamaged, the motor requires no maintenance.
How does cold water affect oil viscosity and motor start-up?
The food-grade dielectric oil has a pour point below -30°C. It stays fluid in cold well water or freezing conditions, allowing motor start-up without extra stress on the windings.
Is thermal overload protection available for single-phase and three-phase NF-O motors?
For single-phase models (e.g., 220V NFO4B series), an automatic-reset thermal overload protector can be integrated into the windings. For three-phase models, use an external magnetic starter or control box with overload and phase-failure relays.
Contact Us
0086 18783276017
info@hualuopumps.com
No. 399, Antai Street, Economic Development Zone, Neijiang City, Sichuan Province, China.
