Page 48 - +GF+ PPR Aquasystem Catalogue 2017_Neat

Butt Fusion Installation

Fusion jointing procedure
Once it has attained the fusion temperature, position the heating
element in the fusion jointing machine. Press the surfaces to be
jointed against the heating element with the force required for
equalisation until the entire circumference of each of the jointing
Join and cool
faces rests completely against it and a bead (see the table) has
formed. Reduce the equalisation pressure almost to 0 (p~ 0.01 N/
mm²). The heating time listed in the table is measured from this
moment.

Once the heating period has elapsed, remove the parts from the
heating element which should then be removed without touching
Leave parts in the fusion jointing machine at
the jointing surfaces and push the heated surfaces together
fusion pressure until the end of the cooling
immediately. The changeover time must not exceed the value
period!
listed in the table. Pay particular attention during jointing that
the parts be moved together swiftly until the surfaces are about
to touch. Then they should be moved together so that they are
in contact along the entire circumference. Next the pressure
should be increased rapidly to the present jointing pressure within
the period of time specified in the table. This pressure must be
maintained during the entire cooling period. Adjustment may be
Fusion check
necessary, especially shortly after the jointing pressure has been
attained.
The jointed parts must stay in the fusion jointing machine under
jointing pressure until the end of the cooling period specified in
the table.

Carrying out the pressure test
A bead should form around the entire
All fusion joints must be allowed to naturally cooled completely
circumference of the pipe. K in the diagram to
before pressure testing, i.e. as a rule wait about 1 hour after the
the left should always be positive.
last joint has been completed.

Approximate values for Butt Fusion of PP 1)
Wall thickness (mm) Equalisation at Heating time ²) Changeover Time to reach full Cooling time ²)
p=0.10 N/mm² p=0.01 N/mm² time max. (sec) jointing (sec) under jointing
Height of bead (sec) p=0.10 N/mm²
(mm) (min)
up to 4.5 0.5 up to 135 5 6 6
4.5 - 7 0.5 135 - 175 5 - 6 6 - 7 6 - 12
7 - 12 1.0 175 - 245 6 - 7 7 - 11 12 - 20
12 - 19 1.0 245 - 330 7 - 9 11 - 17 20 - 30
19 - 26 1.5 330 - 400 9 - 11 17 - 22 30 - 40
26 - 37 2.0 400 - 485 11 - 14 22 - 32 40 - 55
• For exact welding value please refer to our technical support team.
• In accordance with DVS 2207-11

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