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 ProfilesSupport ProfilesMin. diam. in mmMin. slot width in mm
10SQ25210.10
11SQ20 or Q25230.030
12S22S300.050
12SQ25230.030
12SQ35300.050
18S22S or Q35 300.050
18SQ25250.030
18SD453000.20
18S10x33000.20
22S22S or Q35450.10
22SD45 or 10x3 or 25x33000.20
28SQ352150.20
28SD45 or 10x3 or 25x33000.20
34SQ353000.20
34SD453000.20
34S10x3 or 25x33000.20
42SQ35 or D453000.20
42S10x3 or 25x33000.20

Diameters

Outside diameter in mmNumber of support profiles
308
4510
5712
7018
8518
9720
11024
13730
16436
21548
26848
30540
38048
46060
51064
62580
914180

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)

Final products manufactured with slot tubes