|
Repair sleeves are made by
cold rolled plates
longitudinally chamfered with a machine process in order to
obtain a suitable room for the inside backing strip: for a standard strip,
the relevant groove is two times deepest than the strip wall thickness and
twenty percent widest to facilitate the assembly operations in place.
As stated in the last line of the
following table, there is also the possibility to make the repair sleeves
without longitudinal chamfer, by welding an "outside strip" on
the lower shell, in order to facilitate the welding of big thickness where
the sleeve cannot be rotated.
| Longitudinal
chamfers type (standard) |
| Description |
Upper shell |
Lower shell |
Backing strip dim. |
| V 60 |
30° |
30° |
Inside 25 x 1.5mm. |
 |
| ˝
V 30 |
30° |
0° |
Inside 25 x 1.5mm. |
|
| ˝ V 30+5 |
30° |
5° |
Inside 25 x 1.5mm. |
|
| T 90 |
0° |
0° |
Outside (3 x W.t.) x W.t. |
|
|
|
As shown in the picture below,
there is also the possibility to obtain the backing strips from the
chamfer itself, this is normally done when there are particular
requirements concerning the compatibility of the sleeve's raw material and
the strips to be welded. Moreover this system improve a lot the assembly
operations by reducing assembling time and increasing the welding quality.
The thickness of the strip is
progressively reduced in order to match the two parts of the chamfer in
almost all the conditions, even when, for various reasons, the main tube
is out of tolerance.
| Longitudinal
chamfers type (backing support included) |
| Description |
Upper shell |
Lower shell |
Backing strip dim. |
| V 60 |
30° |
30° |
Included 15 x 3 x
1.5mm. |
|
| ˝
V 30 |
30° |
0° |
Included 15 x 3 x
1.5mm. |
|
| ˝ V 30+5 |
30° |
5° |
Included 15 x 3 x
1.5mm. |
|
|
