About Float / floater
A float is part of device that measure the liquid level based on the up and down movements of the liquid level. Not only vehicle's fuel tanks, but also being widely used in other industrial equipments which need function or capability of measuring the level of different liquids.
Where float is used ?
1.Fuel tank level gauges (automobile, motorcycle, trucks etc.)
2.Carburetors (motorcycles, automobile, agricultural machine engines)
3.Engine oil level gauges
4.Transformer oil level indicator
5.LPG level gauges, valves
6.Industrial liquid level sensor
7.Other types of equipment that need level detection sensors
Material of float
Type |
Production technology |
Material |
Problems |
Recommend |
Closed pore foam |
Double-stage foaming |
Nitrile rubber |
none |
★★★★★ |
Single stage foaming |
Polyurethane |
lower performance against fuel with ethanol and methanol |
★★★ |
Resin injection molding |
PP/Nylon/POM |
lower performance against fuel |
★★★ |
Hollow body |
Metal drawing &welding |
Copper |
higher cost, irregular shaped, very small and light weight products cannot be manufactured, any welding default at the joint section can make the float lose the buoyancy |
★★ |
Metal drawing &welding |
Stainless steel |
higher cost, irregular shaped, very small and light weight products cannot be manufactured, any welding default at the joint section can make the float lose the buoyancy |
★★ |
Notes: Currently FDS can supply the floats made of nitrile rubber, polyurethane and POM.
Nitrile rubber( NBR) introduction
To make sure the float itself can work perfectly in different liquids, the float material must be excellent in terms of resistance ability and durability against different liquids and extreme environment. This is why NBR and vulcanization foaming technology was highly recommended.
Nitrile Butadiene rubber, refer as NBR, is a kind of synthetic rubber, which has excellent fuel/oil resistance, high wearing, heat resistance, and good strong adhesion and aging resistance.
NBR float is a closed pore foam object composed of nitrile rubber, its self-independently sealed small space structure can completely block the liquid from penetrating, moreover, its Low liquid absorption rate and uniformity of the pore structure improves product reliability, which can avoid the sinking accident of the device used as the floating material due to the loss of buoyancy.
Cross-section observation under a 1000x electron microscope, showing independent spatial arrangement of small holes
NBR float physical features
Working Temperature:
-50~80ºC,the upper limit of the working temperature can be reached to 149ºC by special treatment.
Density
0.16~0.20 for automotive, transformer, oil level gauges applications
0.25~0.33 for Liquid propane industry(high pressure resistance)
Working pressure:
Up to 30 kg/cm2 (420 psi), but the hydraulic test result for the OPD valve is 53 kg/cm2
Hardness
Minimum 90 Shore A Type, up to 55 Shore D Type
Coefficient of expansion
5x10^-5mm/m/deg. ºC(9.8x10^-5in/in/ºF)
Dimentional &weight variation
Dimention: max. 4% weight: max. 15%
Liquids resistance ablity
High resistance performance against gasoline, diesel,
methanol gasoline, ethanol gasoline, alcohol, kerosene, LPG, transformer oil, petroleum, engine oil etc.