3. Fisher Sub Sieve Sizer Principle 201-6.

3. Fisher Sub Sieve Sizer Principle 201-6.
isher sub sieve sizer manual – hmk-22 fisher sub sieve sizer – merits and limitations of fisher method – air permeability method for determining surface area – fisher sub sieve sizer principle – Fisher Model 95 Sub-sieve Sizer
What a standard Fisher Sub-sieve Sizer consists of ?

HMK-22 Fisher Sub-Sieve Sizer is manufactured by HMKTest, a world leading manufacturer of fisher sub sieve sizer particle size analyzer. HMK-22 fisher sub sieve sizer conforms to ASTM STANDARD B330-12. In addition to fisher sub sieve sizer manual, an HMK-22 Fisher Model 95 Sub-Sieve Sizer consists of following fisher sub sieve sizer parts and accessories:

Air pump

Air filter

Constant pressure regulator

Pressure control
Sample tube
High needle valve
Low needle valve
Manometer
Calculator chart
Sub-sieve sizer calibrator etc.

How a fisher sub sieve sizer works?

HMK-22 Fisher sub sieve sizer -201pic

Turn on HMK-22 Fisher Sub-Sieve Sizer, the air pump generates compressed air and the air passes air filter to filter out impurities, after constant pressure regulator, the air goes through the dryer made up of allochroic silicagel to dehydrate, then the air enters sample tube, after passing through the packed powder sample, part of compressed air enters manometer, read on the calculator chart average particle size (Fisher Number) according to the water level height in manometer, excessive air exits via high needle valve. There is void among tested particles, pressure drop △P is generated after passing the tested powders, when the mass of powder is fixed, the bigger the particle is, the bigger the void among particles is therefore more easily the air passes the powder and the smaller pressure drop is and the higher the manometer water level is and the bigger the size on the calculator chart is, vise versa. The obtained value is fisher number particle size, i.e. averaged particle diameter of surface area of tested powders.
Instructions Fisher Model 95 Sub-Sieve Sizer Catalog No. 14-311A
Perspective of Operating Pinciples
The instrument eliminates all variables and resolves the formulas into a series of curves, which allow average particle size to be read directly from the calculator chart.

1-1 Constant Pressure Regulator
1-2 Pressure Control
1-3 Air Filter
1-4 Air Pump
1-5 Dryer
1-6 Packed Powder Sample
1-7 Sample Tube
1-8 Range Control
1-9 Manometer
1-10 Calculator Chart
1-11 Manometer Level Control

dvs(Fisher Number)- average diameter in microns (one micron = 10-6 meters
k- shape factor
g- acceleration of gravity
ɛ- powder porosity (percentage of voids of tested sample)
η- viscosity of air
L- length or height of compacted sample in cm (measured by operator)
u- flow rate passing sample layer in cm/second

–Tungsten powder fisher sub sieve sizer
HMK-22 Fisher Sub Sieve Sizer/Average Particle Size Analyzer (FSSS) is an optimal tool for sub sieve particle size analysis and has become the best successor of discontinued Fisher Scientific Sub-Sieve Sizer(FSSS) Fisher Model 95. It uses Air Permeability Principle to fast determine the Average Particle Size i.e. Fisher Number of powders. HMK-22 Fisher Sub-Sieve Sizer completely meets international standards about fisher sub sieve sizers ASTM B 330 Standard Test Method for Fisher Number of Metal Powders and Related Compounds and ISO 10070 Metallic powders Determination of envelope-specific surface area from the measurements of the permeability to air of a powder bed under steady-state flow conditions. HMK-22 Fisher Sub Sieve Sizer meets the urgent requirement of the industry to find a quality successor to particle sizing technique by air permeability device such as fisher model 95. It gives operators completely same test experience and the results agrees completely with all the tested data obtained by a discontinued Fisher Scientific Sub-Sieve Sizer Model 95.

SPECIFICATIONS
Voltage Requirement: 220V/115V (+ or -10%), 50-60 Hz
Power Requirement: 0.3 amps (30 Watts)
Range
– Average Particle Diameter: 0.2 to 50 microns (um) – Porosity: 0.25-0.40/0.40-0.80/0.80-0.95
Repeatability:<3%
Accuracy: <3%
Test Method: Air permeability method for determining surface area
Shipping Weight: 18 kg (38 lb.)
Instrument Dimensions: 41.8cm W x 24.6cm D x 73.7cm H

Fiser sub sieve sizer https://www.aimsizer.com