magnetic sealing fluid
Consultancy Research
Consultancy Research Products

 

Role of Ferrofluid in a Seal

Traditional labyrinth rotary seals require constant maintenance to perform at an optimum level. They are also subject to wear and accumulation of particulate material, which can compromise the performance of a seal.

By the use of a ferrofluid to act as a magnetic O-ring and used in conjunction with traditional labyrinth seals, a rotary seal is produced where the shaft of the seal provides hermetic sealing with zero leakage.

SMART SEAL MAGNETIC CIRCUIT

 

 

 

 

 

biocompatible ferrofluid

magnetorheological fluid

ferrofluid

 

 

ferrofluids

ferrofluids

for Sealing Applications

magneto-rheological fluid

for Loudspeaker Applications

magnetorheological fluid

for Inkjet printing

ferrofluids

for Domain Observation

magnetic fluid

for sink float separation

biocompatible ferrofluid

for biomedical Applications

magnetic loudspeaker fluid

 

 

magnetorheological fluid

ferrofluids

 

 

magnetic loudspeaker fluid

magnetic liquid

 

 

magnetic liquid

magnetic sealing fluid

magnetic fluid

 

 

magnetorheological fluid

magnetic fluid

magnetic loudspeaker fluid

 

 

 

Due to the magnetic nature of the ferrofluid seal, foreign particles are actually expelled from the system rather than accumulated.

As the ferrofluid consists of a high quality lubricating oil there is minimal wear. Where a large pressure differential is required, ferrofluid based seals typically give a burst pressure of several atmospheres.

 

biocompatible ferrofluid

Ultimate burst pressure is governed by the number of stages in the seal.

Other sealing applications include the use of ferrofluid to seal hard disk drives. Liquids Research Limited have a proven track record in providing high quality ferrofluids for vacuum and non vacuum sealing applications. We manufacture fluids of high colloidal stability in a variety of carrier liquids, including synthetic oils and in perfluoropolyethers (PFPE) for use in hostile environments.

Fluid specifications

Fluids with saturation magnetisation of up to 600 Gauss and greater can be produced with viscosities between 1000cp and 5000cp. See below for details.

Hydrocarbon based for vacuum and elevated temperature use (100°C+)

 

Ms

(mT)

Median Particle diameter (nm)

Viscosity (mPa-sec)

Vapour Pressure in Pa (27°C)

SHGS4-U 

45

10

3500

< 10-9

For c.g.s. units click here

PFPE for hostile environments

 

Ms

(mT)

Median Particle diameter (nm)

Viscosity (mPa-sec)

Vapour Pressure in Pa (20°C)

SPBS26

45

10

3000

< 10-7

For c.g.s. units click here

Hydrocarbon based for vacuum and non vacuum

 

Ms (mT)

Median Particle diameter (nm)

Viscosity

(mPa-sec)

Vapour Pressure in Pa (20°C)

SHAS1S2-A

60

10

1200

< 10-7

SHAS1S3-A

40

 10 

2000

< 10-7

SHAS1S3-B

30

10

<1000

< 10-7

 For c.g.s. units click here

Hydrocarbon for disc drive sealing

 

Ms

(mT)

Median Particle size (nm)

Viscosity (mPa-sec)

Vapour Pressure in Pa (20°C)

SHAS4-A 

20 

10

500

< 10-7

SHAS4-B

30

10

1000

< 10-7

For c.g.s. units click here

All viscosities are ±10% and Ms values are ± 5% of the quoted values. Viscosity measured at 27°C.

For further information on the use of vacuum sealing fluid click here.

 

Document download

Health and Safety

Ordering Information

 

 

 

magnetic liquid
Typical heavy duty seals

magnetic liquid
Typical 10mm diameter seal

magnetic loudspeaker fluid
The DRIVETHRU

 

 

 

magneto-rheological fluid vacuum seal fluid magneto-rheological fluid
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email mail@liquidsresearch.co.uk  All text & images © Liquids Research Limited 2000