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Guide to float

Superb preciseness of Specific Gravity is achieved with
Independently Closed Cell Foam Structure.

About floats

A float is one of the most important components of a sensor that detects liquid level.
It floats in a fluid such as water or oil, rising and falling with the changing level of liquid.

Structure of RF-2 (NBR float)

You can find the difference between completely closed cells and imcompletely closed cells on the right pictures. If you cut floats with same size, the imcompletely closed cell float will sink, while the completely closed cell float will be almost no change.

  • Completely closed cell

    Each cell is independently closed, the liquid will not go into further, and the buoyancy will not be affected so much.

  • Imcompletely closed cell

    The liquid goes through in the cells, and the float is no longer buoyant.

Float materials and application examples

BUNA-N
RF-2

Fully independent
foam


Made of NBR

This is foamed by the addition of phenolic resin to NBR (nitrile rubber).
Typical applications : Oil, various liquid chemicals

SUS304
SUS316

Internal cavity


Made of
stainless steel

Made of press-molded stainless steel with plasma welding.
Typical applications : Oil, various liquid chemicals, high-temperature and high-pressure equipment

Plastic

mixture of
contiguous and
self-supporting
plastic


Made of PP
(polypropylene)

Made of PP (polypropylene) and nylon foamed in a resin mold.
Typical applications: Water, various liquid chemicals

Wood, cork

Previously, wood and cork were used for floats, but this made it difficult to maintain uniform quality and obtain a stable supply of material. They are not currently used because of quality and cost problems and issues of insertion of sensor magnets.

PVC

SUS and similar
with internal cavity

Previously, wood and cork were used for floats, but this made it difficult to maintain uniform quality and obtain a stable supply of material. They are not currently used because of quality and cost problems and issues of insertion of sensor magnets.

Other types

Products of titanium and fluorine exhibit very good characteristics (including good resistance to high temperature and high pressure). Currently, because of high cost, marketing is difficult and demand is low.