Slot Tubes
- General
- Standard constructions of slot tubes
- Standard tolerances
- Special features
- Finishing
- End pieces
- Reinforcements
- Final products manufactured with slot tubes
General
» Construction Drawing
Slot tubes are welded structures with the support profiles being rods in the axial direction of the tube and surface profiles spirally wound around the support profiles.
Trislot® Slot Tubes are manufactured directly on a machine. They have the unique advantage of very accurate, narrow slot openings and perfect roundness all in one. Slot tubes can be provided with the necessary end pieces for attachments and/or reinforcements.
Conventional manufacturing method
Trislot® manufacturing method (perfect roundness)
Standard constructions of slot tubes (special constructions are possible on request)
The designation of a slot tube describes its construction as follows:
surface wire / support wire x number of support wires.
Example: 12S/Q25 x 8
This means that the profile wire is 12S. The support wire is Q25 and there are 8 support wires, equally spaced over 360°.
Slot tubes with dimensions and/or tolerances other than those described below, are available on request.
Profile combinations
| Surface Profiles | Support Profiles | Min. diam. in mm | Min. slot width in mm |
|---|---|---|---|
| 10S | Q25 | 21 | 0.10 |
| 11S | Q20 or Q25 | 23 | 0.030 |
| 12S | 22S | 30 | 0.050 |
| 12S | Q25 | 23 | 0.030 |
| 12S | Q35 | 30 | 0.050 |
| 18S | 22S or Q35 | 30 | 0.050 |
| 18S | Q25 | 25 | 0.030 |
| 18S | D45 | 300 | 0.20 |
| 18S | 10x3 | 300 | 0.20 |
| 22S | 22S or Q35 | 45 | 0.10 |
| 22S | D45 or 10x3 or 25x3 | 300 | 0.20 |
| 28S | Q35 | 215 | 0.20 |
| 28S | D45 or 10x3 or 25x3 | 300 | 0.20 |
| 34S | Q35 | 300 | 0.20 |
| 34S | D45 | 300 | 0.20 |
| 34S | 10x3 or 25x3 | 300 | 0.20 |
| 42S | Q35 or D45 | 300 | 0.20 |
| 42S | 10x3 or 25x3 | 300 | 0.20 |
Diameters
| Outside diameter in mm | Number of support profiles |
|---|---|
| 30 | 8 |
| 45 | 10 |
| 57 | 12 |
| 70 | 18 |
| 85 | 18 |
| 97 | 20 |
| 110 | 24 |
| 137 | 30 |
| 164 | 36 |
| 215 | 48 |
| 268 | 48 |
| 305 | 40 |
| 380 | 48 |
| 460 | 60 |
| 510 | 64 |
| 625 | 80 |
| 914 | 180 |
Standard tolerances (tighter tolerances are possible on request through the use of special techniques)
| Slot Size: |
± 0.030 mm (max. ± 0.030) ± 0.1 mm (max. ± 0.2) |
for O.D. ≤ 300 mm for O.D. > 300 mm |
| Diameter |
± 0.3 mm ± 0.5 mm ± 2.5 mm |
Ø < 164 mm 164 < Ø < 300 mm Ø > 300 mm |
| Length |
± 2 mm ± 4 mm |
Ø ≤ 300 mm Ø > 300 mm |
Special features
reversed construction
(FITO)
normal construction
(FOTI)
Reversed profile
Normal construction of slot tubes allows for flow out to in filtration. However, flow-in -to-out constructions are also possible.
This construction can also be used when the slot tube is used as support tube for another filter medium, so that only the wedge is in contact with the medium to increase the open area.
Variable slot opening
For special purposes variable slot openings are possible for all diameters.
Continuous cylinders
By using a lot of support profiles, an axial slot can be obtained.
These filter elements are called continuous cylinders.
Support tubes
See support tubes.
Finishing
- Standard finish
- grinding of end surfaces
- removal of loose profile ends
- degreasing and pickling
- Optional finish
- fastening of loose profile ends
- removal of burs of profile ends
- post machining for tighter tolerances
End pieces
 welding ring & closure plate |
 resistance welded closure plate |
 end ring |
 threaded fitting (for diameter > 45 mm) |
 flange |
 welding ring and threaded fitting (for diameters < 45 mm) |
Reinforcements
To protect slot tubes against collapse, reinforcements are optional:
 reinforcement spiral |
 reinforcement cross |
 perforated reinforcement plate (also used as distributor of the fluid over the entire working area of the slot tube) |