Table 7: See below table for the turns required to tighten the Conex Compression joint after hand tightening.
Figure 4
Material
Tube/Pipe
specification
Size
6 mm to 18 mm
22 mm
28 mm to 54 mm
-
Copper
EN 1057 - R250
(Half hard)
No. of turns
1 1/4
1
3/4
-
EN 1057 - R290
(Hard)
No. of turns
1
3/4
1/2
-
EN 1057 - R220
(Annealed)
No. of turns
Liner required SC1
1 1/4
1
-
-
Stainless
steel
EN 10312
(BS4127)
Size
6 mm to 22 mm
28 mm
35 mm to 54 mm
No. of turns
3/4
1/2
-
-
Carbon
steel
EN 10305
Size
6 mm to 22 mm
28 mm
-
-
No. of turns
3/4
1/2
-
-
Plastic
pipe
Polybutylene (PB)
Size
10 mm
15 mm
22 mm
28 mm
No. of turns
1 1/2
1 1/2
1 1/2
1 1/2
Liner PP
C183031000PP
E203031000PP
G233031000PP
H293031000PP
Cross linked
polyethylene
(PE-X)
Size
10 mm
15 mm
22 mm
28 mm
No. of turns
1 1/2
1 1/2
1 1/2
1 1/2
Liner PP
C183031000PP
E183031000PP
G233031000PP
H293031000PP
1. Fitting
2. Stud
3. Compression ring
4. Compression plate
5. Nut
6. Tube
Note: For internal reducers the number of turns must be taken from the size of the connecting tubes not the size of the fitting.
Note: The compression plate before and after correct assembly should be parallel to the face of the fitting body.
Torque values
Size (mm)
Torque value in Nm
6 to 10
20 +/- 5
15
30 +/- 5
22
40 +/- 5
28
55 +/- 5
35 to 54
70 +/- 5
10
Table 8:
The torque values given in Table 8 are given as an
alternative method to the number of turns in Table 7 if
torque wrenches are used. These figures are only for
copper tube.
4.5 Flange fittings – sizes 67 to 108 mm
1. Ensure that the tube and fitting sizes are compatible.
Then cut the tube end square, ensure tube retains its
shape. The tube will then make even contact with the tube
stop in the body of the fitting.
2. Remove any burrs from the tube, both inside and out.
3. One of two methods can be employed for making the joint.
a) The tube can be firmly inserted into the Conex
Compression fitting without removing the compression
plate and compression ring. Care should be taken to
ensure that the compression ring is in the correct position
and that the tube makes firm contact with the tube stop
in the body of the fitting. The 3/8" BSW nuts are then
tightened until hand tight and the same amount of thread
shows on each bolt.
4.6 Internal reducers
Where dedicated fittings do not exist for reduction in
tube-work, the reduction may be achieved with the
use of internal reducers either as a three piece or one
piece configuration. These are manufactured from DZR
(dezincification resistant material CR) or gunmetal,
thereby being resistant or immune to dezincification. They
are suitable for use with our unique ribbed and octagonal
capnut fittings (please refer to page 30 and 31 for more
information).
Note: One piece reducers are not designed for use with
plastic pipes. Only the three piece reducers - S68 can be
used for plastic pipes. Internal reducers must not be used
for gas applications and installations.
The minimum number of turns required is based on
the reduced diameter end. Thus, for a 22 mm x 15 mm
reducer, use the number of turns required for the 15 mm
end. Refer to Table 7.
Reducers rely on a metal to metal seal and care should
be taken to avoid damage prior to assembly. Should
difficulty be experienced, the use of a WRAS listed sealant
is permitted.
4.7 Jointing instructions for gas applications
There are four quick steps to fitting a quality compression
joint that is guaranteed to last:
1. Make the joint in the same way you would join water
11
tubes, following the standard catalogue instructions, but
tighten the capnut 1/8 of a turn less than the specified
number of turns after it has been tightened.
2. Mark the position of the capnut in relation to the body
of the fitting. Then dismantle the joint.
3. Apply a thin smear of anaerobic sealant (in accordance
with EN 751-1 approved for gas applications e.g. Loctite
542 or 577, Rood Foliac Super Red, etc) to the leading
edge of the compression ring.
4. Re-assemble the joint and re-tighten the capnut as
before to its marked position. Finally, tighten the capnut
again by another 1/8 of a turn.
b) The compression plate and compression ring can be
removed by first unscrewing the 3/8" BSW nuts. Then by
locating the compression plate and compression ring onto
the tube in logical sequence, the tube is then inserted into
the fitting, or fitting onto the tube, until positive contact is
reached. The compression ring and compression plate are
then correctly situated in their original position, the nuts
are replaced and tightened until hand tight, with the same
amount of thread showing on each bolt.
4. In both cases the nuts are then further tightened a
minimum of 2 full turns in increments of a 1/2 turn only,
on each position in the sequence shown in Figure 3.
To avoid over tightening the maximum number of turns
is 2 1/2.
Tightening sequence
Figure 3
