Functional Description - Leister ASTRO Manual De Instrucciones

Functional description

• Heating system → The hot air temperature is steplessly adjustable and eletronically controlled. It is a floating
hot wedge. (Illustration A).
• Welding pressure → infinitely variable (steplessly adjustable). The welding pressure is transmitted via
a toggle lever to the pressure rollers. The swivel head guarantees the equalization of the pressure to
both welded sections (c and d) as well as on a welded seam without test channel (Illustration B).
This allows T-joints to be welded easily. During the welding process the pressure adjusts itself linearly to the
change in material thickness of the geomembrane liners.
• Drive → The welding speed is adjustable and electronically controlled in steps of 0.1 m/min / feet. Digital display
of SET and ACTUAL values. The power transmission works through a three stage planetary gear.
Adjusting the hot wedge
Adjusting of the guide rollers for the requested material thickness (Illustration A).
• Adjustments may only be made to the hot-wedge (8) after it has cooled down.
• Engage the automatic wedge-welding machine on the geomembrane liner or film to be welded.
• Stretch the lever (9) (Illustration C).
• Loosen the hexagon cap screw of the rear guide roller (19).
• The distance between the hot wedge (8) and the rear guide roller (19) should be the thickness
of the material and the sharp tongue of the wedge should lie centrically to the pressure rollers
(20/21).
• Tighten the hexagon cap screw of the rear guide roller (19).
• Loosen the hexagon cap screw of the front guide roller (18).
• The distance between hot wedge (8) and front guide roller (18) should be about 1 mm.
• Tighten the hexagon cap screw of the front guide roller (18).
Illustration A / Cross-section diagram of hot wedge system
21
20 19
Illustration B / Cross sectional diagram of an overlap weld
Seam thickness reduction = a – b
a Thickness of the upper and lower membrane
b Thickness of the welded seam
c Welded section 1
d Welded section 2
e Test channel
14
8 17
18 Welding direction
Upper
geomem-
brane liner
26
Lower
geomembrane
liner
c d
b
b
e
8 Hot wedge
9 Lever
17 Pinch roller
18 Front guide roller
19 Rear guide roller
20 Lower drive/pressure roller
21 Upper drive/pressure roller
22 Adjustment screw for swivel head
23 Chain guard of lower part
24 Chain guard of tension arm
25 Chain guard of gear case
26 Fastening screw for hot wedge
Illustration C
a