TUCK-UNDER ROLLER
There are two types of tuck-under rollers:
-Tuck-under forming roller
-Tuck-under finishing roller
The standard tuck-under forming roller
C (Fig.7)
has a radius
D
of 0.8 [mm]
There are more than one version of the tuck-under finishing roller:
-The standard version
E
with a step
F
between the outside diameter and the shoulder (for side tucking) of
2
[mm]
-The version for STELCAP caps
G
with a step
H
between the outside diameter and the shoulder (for side tucking)
which varies according to the cap diameter:
Cap Ø(mm)
H (mm)
22 ÷ 25
1.25
28 ÷ 36
1.5
Special version for STELCAP caps
l
with the step
L
between the ouside diameter and the shoulder (for side tucking)
which can vary according to the diameter of the cap.
Cap Ø (mm) L(mm)
22 ÷ 25
1.25
28 ÷ 36
1.5
11
POSSIBLE TROUBLES
INSUFFICIENT STEP ON TOP OF CAP
Not enough axial load.
Diameter of the pressure-block not adequate for the type of cap. (too big)
CUT ON THE UPPER PART OF THE CAP
Step on top of the cap too deep.
Diameter of the pressure-block too small, making sure that the axial load is the right one to form the step.
IRREGULAR STEP ON TOP OF CAP
Incorrect adjustment of the pressure-block.
Inclined bottle or inclined bottle neck.
Bottle too tight in the center star of the capping machine.
Center star of the capping machine too low.
SCARCE DEPTH OF THREAD
Verify the radial load of the rollers.
Roller arms incorrectly adjusted.
Rollers too wide apart.
THE THREAD ROLLERS MAKE A GROOVE ON THE CAP WITHOUT ENTERING THE START OF THE THREADOF
THE GLASS FINISH.
Gripped rollers.
Rollers adjusted too high.
Pressure-block incorrectly adjusted (unscrewed).
Cap material of poor quality.