widos 5500 - Page 23

Kunststoffschweißtechnik
Starting and Operating Chapter 5
17.02.14 Working Instructions WIDOS 5500 Page 23 of 48
 Check pipe mismatch and gap on the joining pipe ends. According to DVS 2207, the
mismatch on the pipe outer side must not exceed 0.1 x pipe wall thickness, the admissible
gap must not exceed 0.5 mm. The mismatch compensation is carried out by further
tightening or releasing of the clamping nuts. In case mismatch compensation was carried
out, planing must be repeated afterwards.
 The adjustment pressure for the pipe dimension to be welded can be gathered from the
welding table. Add the movement pressure.
Set the resulting pressure value at the pressure relief valve and check it by actuating the
valve lever.
 Open slides again slightly, valve lever on: “BACKWARDS”.
 Gather heating time, maximum change over time, cooling time and bead height for the pipe
dimension to be welded from the table.
 Move the heating element, which has been cleaned and brought to desired temperature,
between the pipes, take care that it lies in the zone of the throat of the tear-off bar (see
Chapter: 4.3).
 Close slides smoothly to the set adjustment pressure, valve lever on: “FORWARDS”.
When the prescribed revolving bead height is reached, reduce pressure. For this purpose,
move the valve lever to position “Pressure release“ until the desired heating pressure is built
up (heating pressure = approx. 10% of the adjustment pressure).
 The heating up time starts now. Press the stop-watch and compare the actual time with the
nominal time taken from the table.
 After expiration of the heating time, open the slide, valve lever on: “BACKWARDS” remove
the heating element as quickly as possible, put it into the protection box and close the slide
smoothly, valve lever on “FORWARDS”.
The maximum time frame for this process is predetermined by the value for the change
over time taken from the table.
 When the welding pressure is built up, press the stop-watch and keep the control lever for
approximately 10s on position „FORWARDS“ so that the hydraulic accumulator can be filled.
During the cooling time re-adjust pressure, if necessary (the pressure for cooling is the same
as the set adjustment pressure).
 After expiration of the cooling time, release pressure, valve lever on: “Pressure release”,
open the climping devices and remove the welded part.
 Open the slide afterwards, valve lever on: “BACKHWARDS”.
The welding process is finished.