AN IMPROVED SYSTEM FOR THE PRODUCTION OF DEFORMATION FREE
BILLETS
INTRODUCTION TO THE FIELD OF INVENTION
This invention relates to an improved system in the production of continuously cast
billets. This invention more particularly, relates to "An improved system for the
production of deformation free billets"
PRIOR ART AND DRAWBACKS
In the known art system in practice the hot billets pass through withdrawn and
straightening rolls get deformed if the pressure is not correctly regulated. The
regulated pressure has got two levels. The higher pressure (HP) is for taking in and
out the dummy bar and the lower pressure (LP) is for withdrawal of hot billets. This
pressure change over between HP and LP operate through 5/2 - way type solenoid
based system. When the joint of dummy bar - hot billet strand joint comes near the
withdrawal roll, the PLC (Programmable Logic Controller), based on the length of
strand cast, generates a signal for energisation of LP solenoid coil. However, due to
malfunctioning to the valve, some times switch over to LP does not take place even
though the said solenoid is energized and the pressure remains high. This leads to
deformation of hot billets due to high pressure. The previous system does not have
any provision to indicate the switchover from high to low pressure and vice-versa.
OBJECTS OF THE INVENTIONS.
It is therefore, a primary object of the invention to propose an improved system,
which will have a pressure switch with high and low pressure contacts to obtain
positive feedback of the downstream line pressure.
It is another object to propose such a system, which will also have an indication panel
to monitor the status of the line pressure condition as well as solenoid energisation
condition to initiate corrective measure during valve malfunctioning to avoid
deformation of hit billets.

It is a further object of the invention to propose such a system, which will include a
visual alarm in the control desk to indicate the malfunction of the valve to take quick
corrective action.
Such as herein described there is an improved system for the production of
deformation free billets being synchronized such that the billets passing through the
withdrawal and straightening rolls do not get deformed comprising of a pneumatic
circuit for each strand of a multi strand casting machine, said circuit comprising:
i) a compressed air header provided with an air filter, a pressure regulator and a
lubricator in the compressed air inlet;
ii) an impulse pipe connecting said air header to a solenoid operated detented valve
with a manual override;
iii) said impulse pipe further comprising a branch or loop line connected to a pressure
regulator;
iv) said pressure regulator configured to operate a pneumatic cylinder for a
withdrawal of roll;
v) the said solenoid operated detented valve with manual override is configured to
operate a solenoid valve through a pressure switch,
vi) the said solenoid valve is adapted to operate the a pneumatic cylinder for
straightening of roll; and
vii) the said pressure switch is augmented by said solenoid operated detented valve
with manual override.
These and other objects of the invention will be more clearly understood from the
following paragraphs.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS.
Figure 1 of the accompanying drawings schematically represents a preferred
pneumatic circuit diagram typical for one strand in a six strand caster.
Figure 2 illustrates schematic diagram for regulation of withdrawal and straightening
roll pressure.

DETAILED DESCRIPTION.
It will be seen from figure 1 that while it describes only a one strand circuit, there are
six such circuits for the six strand casters. All the details are therefore, similar for all
the six strands.
In figure 1, a 2" NB compressed air Header 10 is provided with a filter (3) pressure
regulator (4) and lubricator (5).
The necessary compressed air is passed through a ½ NB impulse pipe (11A) to the
solenoid valve.
The pipe (11A) also divides the compressed air and by another connector (11B)
feeds the air to an existing pressure regulator (9), which acts on an existing
pneumatic cylinder for withdrawal roll.
The newly introduced solenoid operated detented valve with manual override
operates through the pressure switch (2) the existing solenoid valve (6) which
influences the existing pneumatic cylinder (8) for straightening roll.
Thus the high/low pressure switch (2) is augmented by the solenoid valve (1) with
manual override.
It is important to note the following
1. There are six such circuits connected to the 2" NB head in such
caster in DSP. Only one such circuit is shown for clarity.
2. Identical system has been installed in both the casters.
3. All pressure switches have been installed in a separate panel for
each caster.
4. Indication of High and Low pressure has been provided in a
separate panel in MCD of each caster.

From figure 2, the panel for a six caster will be clear as to how it has the change over
valve panel (12) pressure switch panel (13) six strand indication panel (14) and the
main control (15).
The improved pressure regulation system for withdrawal and straightener rolls was
designed based on factors like low pressure and high pressure requirement for rolls.
Preferably a 4-way 5 -ported 2-position dual solenoid operated detented type valve
with manual override facility was installed. The valves are provided with manual
override kit to facilitate manual change over from HP to LP and vice versa in case of
malfunctioning.
The pressure switches are connected to the pneumatic line downstream of the
solenoid operated directional valve through isolation valve. The inlet ports for the
pressure switches are ½ NB. All the pressure switches for each caster were
installed in a separate panel by the side of the existing pneumatic panel. The
pressure switches are having two contract points for indicating HP or LP after the
solenoid valve.
The indicator panel complete with all the necessary electrical accessories, one for
each caster in the respective MCD, is housed with 24 nos. LED pin type indicator
lamps of suitably chosen colour for indicating HP or LP of solenoid energisation
condition of pressure switch contract. The control cables from each Pressure Switch
Panel were terminated in the indicator panel. Each of the indicator lamps are
numbered and tagged in relation to the solenoid valves for the corresponding strand
in the caster for corrective action during operation. The existing MCD is having
facility for indication of HP or LP of solenoid energisation condition. Necessary cable
looping for these indicators were done from the existing system is placed inside the
indicator panel with input and output isolators.
All the pressure switch contacts to indictor lamps are through interposing relays. The
interposing relays are mounted inside the indicator panel.
The system went through intensive test and it was found deformation due to system
problem has been completely eliminated.

WE CLAIM:
1. An improved system for the production of deformation free billets being
synchronized such that the billets passing through the withdrawal and straightening
rolls do not get deformed comprising of a pneumatic circuit for each strand of a multi
strand casting machine, said circuit comprising:
i) a compressed air header provided with an air filter, a pressure regulator and a
lubricator in the compressed air inlet;
ii) an impulse pipe connecting said air header to a solenoid operated detented valve
with a manual override;
iii) said impulse pipe further comprising a branch or loop line connected to a pressure
regulator;
iv) said pressure regulator configured to operate a pneumatic cylinder for a
withdrawal of roll;
v) the said solenoid operated detented valve with manual override is configured to
operate a solenoid valve through a pressure switch,
vi) the said solenoid valve is adapted to operate the a pneumatic cylinder for
straightening of roll; and
vii) the said pressure switch is augmented by said solenoid operated detented valve
with manual override.
2. A system as claimed in Claim 1, wherein the casting is carried out in
continuous casting machine.
3. A system as claimed in claims 1 & 2, wherein said pressure switch is a dual
throw high and low pressure switch having high and low pressure contacts so as to
obtain positive feedback of the downstream line pressure.
4. A system as claimed in claims 1 to 3, wherein there is provided an indication
panel for each strand system so as to enable monitoring of the status of the line
pressure condition as well as solenoid energisation condition.

5. A system as claimed in Claim 4, wherein said indication panel is associated
with a pressure switch panel and a changeover valve panel.
6. A system as claimed in Claim 5, wherein the said indication panel has a main
control desk and is connected to a power supply.

7. A system as claimed in claims 1 to 6, wherein is system is configured for at
least six strand billets casting machine having six such multiples of identical system
associated with an indication panel in combination six high and low air pressure
switch indicator and six changeover indicators associated with main indication panel
depicting the said six air pressures and solenoid energisation with a main control
desk connected to a power supply source.

ABSTRACT

AN IMPROVED SYSTEM FOR THE PRODUCTION OF DEFORMATION FREE
BILLETS
The present invention relates to an improved system for the production of
deformation free billets being synchronized such that the billets passing through the
withdrawal and straightening rolls do not get deformed comprising of a pneumatic
circuit for each strand of a multi strand casting machine, said circuit comprising a
compressed air header provided with an air filter, a pressure regulator and a
lubricator in the compressed air inlet; an impulse pipe connecting said air header to a
solenoid operated detented valve with a manual override; said impulse pipe further
comprising a branch or loop line connected to a pressure regulator; said pressure
regulator configured to operate a pneumatic cylinder for a withdrawal of roll; the said
solenoid operated detented valve with manual override is configured to operate a
solenoid valve through a pressure switch, the said solenoid valve is adapted to
operate the a pneumatic cylinder for straightening of roll; and the said pressure
switch is augmented by said solenoid operated detented valve with manual override.