HAVER & BOECKER TYLER Ro-Tap RX-29, Operating Instructions Manual

Page: 23 / 44

© Copyright 2010 by HAVER & BOECKER Page 23/44
9. Test Sieves
Test sieves with 200 mm or 8“ (203 m
m) diameter can be used for most of the sieving analyses. The
standard effective height is 50 mm = 2”. Two test sieves with half effective height (25 m = 1”) can be
used, too. If ever possible test sieves with standard effective
height should be used. When disassembling test sieve sets with half height test sieves sieving material
may be spilled, sieving results are not reliable.
10. Sieving with the RO-TAP Test Sieve Shaker
The RO-TAP Test Sieve Shaker reproduces the circular and tapping motion given to test sieves in hand
sieving, but with a uniform, mechanical action.
The results of the following sieving analysis with the RO-TAP prove its superiority to hand sieving. A
sample of a fine powdered low degree copper ore, cluster-
free with a lot of “slime” or dust particles has
been chosen and divided to a 100 gram sample with a sample splitter.
Three sieving analyses of 20 minutes on two RO-TAP Test Sieve Shakers have been executed with the
same sample for each of the three analyses. Analysis 1 and 2 have been done with RO-
TAP “A”, analysis
3 with RO-
TAP “B”.
The results underline that all data can be compared.
Aperture Width
in Micrometer
A.S.T.M. No. Tyler
Mesh
Test No. 1
RO-TAP A
Mass fraction in
%
Test No. 2
RO-TAP A
Mass fraction in
%
Test No .3
RO-TAP B
Mass fraction in
%
600 30 28 33.4 33.5 33.7
425 40 35 18.1 18.0 18.0
300 50 48 11.0 11.1 11.1
212 70 65 8.2 8.2 8.2
150 100 100 7.2 7.3 7.2
75 200 200 9.3 9.4 9.4
sieve pan 12.8 12.5 12.4
The results of the three sieving analyses nearly are the same. Tests No. 1 and Tests No. 2 show that the
machine guarantees reproducible analyses with the same sieving material. Comparing the analyses No. 1
and No. 2 with analysis No. 3 shows that the sieving action of the two machines is nearly identical. Up to
six test sieves with full effective height or up to 13 test sieves with half effective height can be used in a
sieve set.
When using intermediate pans three different material quantities can be analysed with full effective height
test sieves and up to seven with half effective height test sieves at the same time.