**Vibrating Grizzly Feeder**

## Feed Capacity

The capacity of vibrating grizzly feeders is calculated according to the following formula:

Q=3600 x f1 x f2 x f3 x L x H x V

where,

- Q=Feed Capacity in (m3/hr)
- To obtain capacity in Tons per Hour, multiply by bulk density of the material. Qt = Q x bd
- bd = 1.6 Tons/m3 for sand and crushed stone

- To obtain capacity in Tons per Hour, multiply by bulk density of the material. Qt = Q x bd
- f1 is the Size Factor
- f1 = 1 for sand
- f1 = 0.8 to 0.9 for crushed stone up to 150mm
- f1 = 0.6 for crushed stone over 150mm

- f2 is the Moisture Factor
- f2 = 1 for dry material
- f2 = 0.8 for wet material
- f2=0.6 for sticky clay like material

- f3 is the Angle of Inclination factor
- f3=1.3 for angle of inclination = 5°
- f3=1.6 for angle of inclination = 10°

- L(m) = Width of the Vibrating Grizzly Feeder in meters
- H(m) = Height of the material layer on the table of the Vibrating Grizzly Feeder
- H = 0.2 x L for sand and crushed stone below 40mm
- H = 0.3 x L for crushed stone upto 150mm
- H = 0.4 x L for crushed stone over 150mm

- V = Speed of the flow of material on the Vibrating Grizzly Feeder
- V depends upon
- RPM of the Rotating Weights (i.e. RPM of the Vibro Motor or Vibrator Shaft)
- Stroke of the Vibrating Grizzly

- Use the table below to find out the value of V

**V (m/s) = Speed of flow of material on the Vibrating Grizzly****Stroke = Amplitude x 2****6mm****8mm****10mm****12mm****14mm****RPM****700**0.1 0.135 0.185 0.235 0.32 **750**0.135 0.175 0.215 0.255 0.335 **800**0.175 0.2 0.235 0.275 0.35 **850**0.205 0.225 0.265 0.29 0.36 **900**0.225 0.25 0.28 0.31 0.37 **950**0.25 0.27 0.3 0.325 0.375 **1000**0.27 0.285 0.31 0.335 0.38

- V depends upon

### Sample Calculation for CPC Vibrating Grizzly Feeder Model VGFE 4010

#### Sample Process Parameters:

- Material to be Fed : Blasted Quarry Stone 100mm to 500mm, with around 10% Overburden, wet sticky clay like conditions
- Size Factor, f1 = 0.6
- Moisture Factor, f2 = 0.6

#### Grizzly Parameters:

- Width of Vibrating Grizzly, L = 1m
- Height of material layer on the table, H = 0.4 x L = 0.4m
- Angle of Inclination of Vibrating Grizzly = 5°
- So, f3 = 1.3

- RPM of Vibrating Grizzly:
- The RPM of the grizzly is adjustable between 750 to 1000 using a variable frequency drive.
- For Sample Calculation, let us assume the RPM to be set at 850 RPM

- Stroke of Vibrating Grizzly
- The Stroke is adjustable between 5mm and 10mm by altering the eccentric weights of the Vibro motor
- Let us assume the Stoke to as 8mm

- By using RPM=850 and Stroke=8mm, from the table above, we get V = 0.225 m/s

So, Finally we have

f1 = 0.6

f2 = 0.6

f3 = 1.3

L = 1m

H = 0.4 x L = 0.4m

V=0.225 m/s

Using the Formula, Q=3600 x f1 x f2 x f3 x L x H x V, we get

Q=3600 x 0.6 x 0.6 x 1.3 x 1 x 0.4 x 0.225 = 151.6 m3/hr

Bulk density of Stone, bd = 1.6 Tons/m3

So, Q in Tons/Hr or TPH = 151.6*1.6 = 242.6 TPH

Hence, the capacity of CPC Vibrating Grizzly Model VGFE4010 set at 850 RPM and 8mm stroke is around 240 TPH