SPIRAL SCREENS
The Continuous slot -wire wrapped screen is an absolutely new and effective product. It is manufactured by wrapping a wedged steel wire around loading rods which are placed according to the generatrices of a cylinder. Both steel wire and rods can be of different dimensions depending on collapse pressure and tensile stress that the screens have to bear. The wire is welded on the rods by induction.
During construction a computerized system checks and manages all the parameters in order to assure a perfect welding in every crossing point with rods. 
Moreover the system controls that coils formed by wrapping the wire are always at the same distance, thus generating a continuous slot which has the same dimension in every part of the screen.
This particular construction allows to obtain a larger open area compared to other types of screen (around 50% of total area) avoiding turbulences and consequent loss of water capacity.
Wire shape and position (with the larger side outwards) allow the screen filter most of the grains and therefore only the smallest ones pass through slipping inside without clogging the slots (Pic. 1).
OUR RANGE
Diameters: from 62 to 1016 mm
Slots: from 0,25 to 4,00 mm
Lengths: upon request
Connections: welding ends with collars, M/F threaded couplings
Materials: AISI 304 and 316 L stainless steel , carbon steel
Finishing: carbon steel screens can be supplied electro galvanized or coated with waterborne base painting
SPIRAL SCREENS THEORETICAL YIELD
% |
Open area |
R |
Flow rate ( litres per meter of screen every second) |
BARS |
Collapse resistance |
DIAMETER |
SLOT 0,25 mm |
SLOT 0,50 mm |
SLOT 0,75 |
SLOT 1,00 |
SLOT 1,50 |
SLOT 2,00 |
|||||||||||||
UT.mm |
NS.mm |
% |
R |
BARS |
% |
R |
BARS |
% |
R |
BARS |
% |
R |
BARS |
% |
R |
BARS |
% |
R |
BARS |
62 |
49 |
10,2 |
0,6 |
302 |
18,5 |
1,1 |
274 |
25,4 |
1,5 |
251 |
31,3 |
1,8 |
231 |
40,5 |
2,4 |
200 |
46,7 |
2,8 |
176 |
73 |
60 |
10,2 |
0,7 |
185 |
18,5 |
1,3 |
168 |
25,4 |
1,7 |
154 |
31,3 |
2,2 |
142 |
40,5 |
2,8 |
122 |
46,7 |
3,3 |
108 |
78 |
65 |
10,2 |
0,7 |
152 |
18,5 |
1,4 |
138 |
25,4 |
1,9 |
126 |
31,3 |
2,3 |
116 |
40,5 |
3,0 |
100 |
46,7 |
3,5 |
88 |
90 |
77 |
10,2 |
0,9 |
99 |
18,5 |
1,6 |
90 |
25,4 |
2,2 |
82 |
31,3 |
2,7 |
76 |
40,5 |
3,4 |
65 |
46,7 |
4,0 |
58 |
102 |
89 |
10,2 |
1,0 |
68 |
18,5 |
1,8 |
61 |
25,4 |
2,4 |
56 |
31,3 |
3,0 |
52 |
40,5 |
3,9 |
45 |
46,7 |
4,6 |
40 |
115 |
102 |
10,2 |
1,1 |
47 |
18,5 |
2,0 |
43 |
25,4 |
2,8 |
39 |
31,3 |
3,4 |
36 |
40,5 |
4,4 |
31 |
46,7 |
5,2 |
28 |
128 |
115 |
10,2 |
1,2 |
31 |
18,5 |
2,2 |
31 |
25,4 |
3,1 |
28 |
31,3 |
3,8 |
26 |
40,5 |
4,9 |
23 |
46,7 |
5,7 |
20 |
140 |
127 |
10,2 |
1,3 |
26 |
18,5 |
2,4 |
24 |
25,4 |
3,3 |
22 |
31,3 |
4,1 |
20 |
40,5 |
5,3 |
17 |
46,7 |
6,3 |
15 |
153 |
140 |
10,2 |
1,5 |
20 |
18,5 |
2,7 |
18 |
25,4 |
3,7 |
17 |
31,3 |
4,5 |
15 |
40,5 |
5,8 |
13 |
46,7 |
6,9 |
12 |
165 |
152 |
10,2 |
1,6 |
16 |
18,5 |
2,9 |
14 |
25,4 |
3,9 |
13 |
31,3 |
4,9 |
12 |
40,5 |
6,3 |
11 |
46,7 |
7,4 |
9 |
176 |
163 |
10,2 |
1,7 |
13 |
18,5 |
3,1 |
12 |
25,4 |
4,2 |
11 |
31,3 |
5,2 |
10 |
40,5 |
6,7 |
9 |
46,7 |
7,9 |
8 |
182 |
169 |
10,2 |
1,7 |
12 |
18,5 |
3,2 |
11 |
25,4 |
4,4 |
10 |
31,3 |
5,4 |
9 |
40,5 |
6,9 |
8 |
46,7 |
8,2 |
7 |
192 |
179 |
10,2 |
1,8 |
10 |
18,5 |
3,3 |
9 |
25,4 |
4,6 |
8 |
31,3 |
5,7 |
8 |
40,5 |
7,3 |
7 |
46,7 |
8,6 |
6 |
208 |
195 |
10,2 |
2,0 |
8 |
18,5 |
3,6 |
7 |
25,4 |
5,0 |
7 |
31,3 |
6,1 |
6 |
40,5 |
7,9 |
5 |
46,7 |
9,3 |
5 |
214 |
201 |
10,2 |
2,1 |
7 |
18,5 |
3,7 |
7 |
25,4 |
5,1 |
6 |
31,3 |
6,3 |
6 |
40,5 |
8,2 |
5 |
46,7 |
9,6 |
4 |
227 |
212 |
7,7 |
1,6 |
14 |
14,3 |
3,1 |
13 |
20,0 |
4,3 |
12 |
25,0 |
5,3 |
12 |
33,3 |
7,1 |
10 |
40,0 |
8,6 |
9 |
236 |
221 |
7,7 |
1,7 |
13 |
14,3 |
3,2 |
12 |
20,0 |
4,4 |
11 |
25,0 |
5,6 |
10 |
33,3 |
7,4 |
9 |
40,0 |
8,9 |
8 |
243 |
228 |
7,7 |
1,8 |
12 |
14,3 |
3,3 |
11 |
20,0 |
4,6 |
10 |
25,0 |
5,7 |
9 |
33,3 |
7,6 |
8 |
40,0 |
9,2 |
8 |
247 |
232 |
7,7 |
1,8 |
11 |
14,3 |
3,3 |
10 |
20,0 |
4,7 |
10 |
25,0 |
5,8 |
9 |
33,3 |
7,7 |
8 |
40,0 |
9,3 |
7 |
261 |
246 |
7,7 |
1,9 |
9 |
14,3 |
3,5 |
9 |
20,0 |
4,9 |
8 |
25,0 |
6,1 |
8 |
33,3 |
8,2 |
7 |
40,0 |
9,8 |
6 |
267 |
252 |
7,7 |
1,9 |
9 |
14,3 |
3,6 |
8 |
20,0 |
5,0 |
8 |
25,0 |
6,3 |
7 |
33,3 |
8,4 |
6 |
40,0 |
10,1 |
6 |
290 |
275 |
7,7 |
2,1 |
7 |
14,3 |
3,9 |
6 |
20,0 |
5,5 |
6 |
25,0 |
6,8 |
6 |
33,3 |
9,1 |
5 |
40,0 |
10,9 |
4 |
298 |
281 |
5,9 |
1,7 |
12 |
11,1 |
3,1 |
12 |
15,8 |
4,4 |
11 |
20,0 |
5,6 |
10 |
27,3 |
7,7 |
9 |
33,3 |
9,3 |
9 |
304 |
287 |
5,9 |
1,7 |
11 |
11,1 |
3,2 |
11 |
15,8 |
4,5 |
10 |
20,0 |
5,7 |
10 |
27,3 |
7,8 |
9 |
33,3 |
9,5 |
8 |
323 |
306 |
5,9 |
1,8 |
10 |
11,1 |
3,4 |
9 |
15,8 |
4,8 |
9 |
20,0 |
6,1 |
8 |
27,3 |
8,3 |
7 |
33,3 |
10,1 |
7 |
342 |
325 |
5,9 |
1,9 |
8 |
11,1 |
3,6 |
8 |
15,8 |
5,1 |
7 |
20,0 |
6,4 |
7 |
27,3 |
8,8 |
6 |
33,3 |
10,7 |
6 |
350 |
333 |
5,9 |
1,9 |
8 |
11,1 |
3,7 |
7 |
15,8 |
5,2 |
7 |
20,0 |
6,6 |
6 |
27,3 |
9,0 |
6 |
33,3 |
11,0 |
5 |
357 |
340 |
5,9 |
2,0 |
7 |
11,1 |
3,7 |
7 |
15,8 |
5,3 |
6 |
20,0 |
6,7 |
6 |
27,3 |
9,2 |
5 |
33,3 |
11,2 |
5 |
377 |
357 |
5,6 |
2,0 |
12 |
10,6 |
3,8 |
11 |
15,2 |
5,4 |
11 |
19,2 |
6,8 |
10 |
26,3 |
9,3 |
9 |
32,3 |
11,5 |
8 |
406 |
386 |
5,6 |
2,1 |
9 |
10,6 |
4,1 |
9 |
15,2 |
5,8 |
8 |
19,2 |
7,3 |
8 |
26,3 |
10,1 |
7 |
32,3 |
12,4 |
7 |
428 |
408 |
5,6 |
2,3 |
8 |
10,6 |
4,3 |
8 |
15,2 |
6,1 |
7 |
19,2 |
7,7 |
7 |
26,3 |
10,6 |
6 |
32,3 |
13,0 |
6 |
455 |
435 |
5,6 |
2,4 |
7 |
10,6 |
4,5 |
6 |
15,2 |
6,5 |
6 |
19,2 |
8,2 |
6 |
26,3 |
11,3 |
5 |
32,3 |
13,8 |
5 |
480 |
459 |
5,3 |
2,4 |
8 |
10,0 |
4,5 |
7 |
14,3 |
6,5 |
7 |
18,2 |
8,2 |
7 |
25,0 |
11,3 |
6 |
30,8 |
13,9 |
6 |
508 |
487 |
5,3 |
2,5 |
7 |
10,0 |
4,8 |
6 |
14,3 |
6,8 |
6 |
18,2 |
8,7 |
6 |
25,0 |
12,0 |
5 |
30,8 |
14,7 |
5 |
531 |
510 |
5,3 |
2,7 |
6 |
10,0 |
5,0 |
5 |
14,3 |
7,2 |
5 |
18,2 |
9,1 |
5 |
25,0 |
12,5 |
5 |
30,8 |
15,4 |
4 |
558 |
537 |
5,3 |
2,8 |
5 |
10,0 |
5,3 |
5 |
14,3 |
7,5 |
4 |
18,2 |
9,6 |
4 |
25,0 |
13,1 |
4 |
30,8 |
16,2 |
4 |
582 |
561 |
5,3 |
2,9 |
4 |
10,0 |
5,5 |
4 |
14,3 |
7,8 |
4 |
18,2 |
10,0 |
4 |
25,0 |
13,7 |
3 |
30,8 |
16,9 |
3 |
608 |
587 |
5,3 |
3,0 |
4 |
10,0 |
5,7 |
4 |
14,3 |
8,2 |
3 |
18,2 |
10,4 |
3 |
25,0 |
14,3 |
3 |
30,8 |
17,6 |
3 |
629 |
608 |
5,3 |
3,1 |
3 |
10,0 |
5,9 |
3 |
14,3 |
8,5 |
3 |
18,2 |
10,8 |
3 |
25,0 |
14,8 |
3 |
30,8 |
18,2 |
2 |
709 |
688 |
5,3 |
3,5 |
2 |
10,0 |
6,7 |
2 |
14,3 |
9,6 |
2 |
18,2 |
12,2 |
2 |
25,0 |
16,7 |
2 |
30,8 |
20,6 |
2 |
790 |
769 |
5,3 |
3,9 |
2 |
10,0 |
7,4 |
2 |
14,3 |
10,6 |
2 |
18,2 |
13,5 |
1 |
25,0 |
18,6 |
1 |
30,8 |
22,9 |
1 |
860 |
838 |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
914 |
892 |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
960 |
938 |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
1016 |
994 |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
--- |
For space reasons the table shows only part of spiral screens range
