Filter Media Specifications for Water Filtration

Specifying Procedure

When specifying filter media size, it is best to state the Effective Size and Uniformity Coefficient or the Nominal Size required. Only one system should be used. If in doubt, please contact our technical service team who will be pleased to assist in explaining the best method for specifying. 

Effective Size (e.s.) - The sieve size opening that will allow 10 percent, by weight, of a representative sample for the filter material to pass. 

Uniformity Coefficient (U.C.) - The ratio of the sieve size opening from which 60 percent of the sand, by weight, will pass divided by the sieve size opening from which 10 percent of the sand, by weight, will pass. 

Typical Filtration Bed Profiles

Typical Specifications

PRODUCT 3
GRAVEL
4
GRAVEL
5
GRAVEL
6
SAND
6.5
SAND
7C
SAND
7M*
SAND
W9
SAND
SIEVE SIZE 
(mm)
TYPICAL GRADING ANALYSIS TEST RESULTS 
PERCENT PASSING (%)
40.00 . . . . . . . .
22.40 100 . . . . . . .
19.00 82 . . . . . . .
13.20 16 100 . . . . . .
11.20 2 92 . . . . . .
9.50 . 60 100 . . . . .
6.70 . 10 99 . . . . .
4.75 . 1 46 . . . . .
3.35 . . 4 100 . . . .
2.36 . . 1 87 . . . .
2.00 . . . 60 100 . . .
1.75 . . . 16 99 . . .
1.40 . . . 1 98 100 100 .
1.21 . . . . 59 99 99 .
1.00 . . . . 14 85 96 .
0.85 . . . . 8 63 84 .
0.71 . . . . 1 27 70 .
0.60 . . . . . 10 34 100
0.50 . . . . . 3 8 99
0.43 . . . . . 1 2 98
0.30 . . . . . . 1 81
0.21 . . . . . . . 39
0.15 . . . . . . . 5
0.075 . . . . . . . 1
NOMINAL SIZE
(mm)
12-25mm 6-12mm 3-6mm 1.5-3.0 0.8-1.8 0.5-1.3 0.4-1.2 0.1-0.5
LIMITS
(%)
8% +/- 8% +/- 8% +/- 8% +/- . . . .
EFFECTIVE SIZE
(mm)
. . . . 0.85-0.95 0.55-0.65 0.45-0.55 .
UNIFORMITY
COEFFICIENT
. . . . <1.5 <1.5 <1.5 .
BULK DENSITY
(tonne/m3)
1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5
SPECIFIC GRAVITY 2.65 2.65 2.65 2.65 2.65 2.65 2.65 2.65
ACID SOLUBILITY
1:1 HCI Solution
<2% <2% <2% <2% <2% <2% <2% <2%
 
* 7M products are made to order only
* If these standard sizes are unsuitable, please contact our technical staff for your specific needs.

 

 

Testimonial

UnderWater World has been doing business with River Sands Pty Ltd for a number of years and have always found them to be reliable and efficient, timely and cost effective. The quality of their filter media products has always met our high expectations and it has been a pleasure to have them as a supplier.

Neil Swann, Marketing Manager, UnderWater World, Mooloolaba.