ncreased automation can help the pharmaceutical industry make more efficient usage of energy and raw materials; improve safety in working conditions; enhance regulatory compliance, and improve both product quality and consistency.
2. Control systems
1. Feed forward control system:
• The trouble with simple feed back control loop is that compensatory action is
taken only after a disturbance has affected the process output. The strategy in
feed forward control is to anticipate the effect of disturbances that will upset the
process by sensing them and compensating for them before they can affect the
process.
• Feed forward is usually combined with feed back control as shown in figure
because complete compensation of disturbance is not possible.
3. 2. Continuous control system
In continuous control the usual objective is to maintain the value of an
output variable at a desired level similar to the operation of a feedback
control system.
E.g. the control of output of a chemical reaction that depends on the
temperature, pressure and input flow rates of several reactants. All of
these variable and/or parameters are continuous.
4. 3. Discrete control system
In discrete control the parameter and variables of the system are changed at discrete moment
in time. They have two distinct state, open/on or closed/off. The changes are defined in advance
by means of a program of instruction.
They are mainly of two types : 1. Event driven changes – changes with respect to some event
2. Time driven changes – changes after certain time laps
Comparison factor Continuous control in process
industries
Discrete control in
discreet industries
Typical measure of product
output
Weight, liquid volume
measures, solid volume
measures
Number of parts,
number of product
Typical quality measures
finish
Consistency, concentration of
solution absence of
contaminants, conformations to
specification product reliability
Dimension, surface
appearance, absence of
defects,
Typical variable and
parameters
Temperature, volume flow rate,
pressure
Position, velocity,
acceleration force
Typical sensor photoelectric Flow meter, thermocouples,
pressure sensor
Limit switches, sensor,
stream gauges,
piezoelectric sensor
Typical actuators Valves, heaters, pumps Switches, motors,
pistons
Typical process time
constants
Seconds, minutes, hours, Less than a second
5. 4. Digital Computer Control:-
The use of digital computers to control an industrial process had its origin in the
continuous process industries in the late of 50s. Today virtually industrial process
contain new installation are controlled by digital computers based on microprocessor
technology.
Factors that determine weather a computer can operate in real time include:
• The speed of the controller’s central processing unit (CPU) and its interfaces
• Controller’s operating system
• Design of application software
• The number of different input/output events to which the controller is designed to
respond.
Forms of computer process control:
There are various ways in which computers can be used to control a process.
1. Process monitoring : This process is used simply for collection of data.
6. 2. Open loop process control : Here, regulation of process is
done but computer does not require feedback data.
3. Closed loop process control : Here regulation process is
done with the help of feedback data collected.
7. Poling (Data sampling)
In computers process control refers to the periodic sampling of data
that indicates the status of the process.
Interlocks
It is the safeguard mechanism for coordinating the activities of two
or more devices and preventing one device from interfacing with the
others.
Interrupt system
It is a computer control feature that permits the execution of the
current program to be suspended to execute another program or
subroutine in response to an incoming signal indicating a higher
priority event.
Exception handling
An exception handling is an event that is outside the normal or
desired operation of the process or control system. It is a form of
error detection and recovery.
Capability of computer control:
8. 5. Programmable logic control (PLC):-
A programmable logic controller can be defined as a microcomputer –
based controller that uses stored instructions programmable memory to
implement logic, sequencing, timing, counting, and arithmetic functions
through digital or analog input/output modules, for controlling machines
and process.
Components of PLC
• A microprocessor
• Memory
• Input/output circuits and
terminals
• Programming interface
9. 6. Numerical control (NC):-
• Numerical control (NC) can be define as a form of
programmable automation in which the process or
mechanical action of machine tool is controlled by
numbers, letters and symbols.
• It involves the use of the computer (a microcomputer) to
direct a machine tool through a sequence o f processing
steps defined by a program of instruction that specifies
the details of each steps and their sequence.
10. Basic component of a NC system:-
A program of instruction:-
It is the detailed step by step commands that direct the action of the processing
equipment. In machine to applications, the program of instruction is called a part program
and the person, who prepares the program, is called a part programmer.
A machine control unit
The machine control unit (MCU) consists of a microcomputer and related control
hardware that stores the program of instruction and executes it by converting command
into mechanical action of the processing equipment, one of command as a time.
Processing unit
The processing equipment accomplices the processing steps to transform the starting work
piece into a completed part. Its operation is directed by the machine control unit, which in
turn is driven by the part program.
11. 7. Distributed control system (DCS):-
Distributed control system is a method where control of process is distributed among
different unit processes. Each hardware item performed a specific task, and
information is passed between the various items via a dual data highway. This
highway provides good security for communications.
Advantages
• Batch, sequence, and continuous control
are available.
• Data logging and data storage capacity.
• Calculation on the stored data can be
performed.
• Easily expandable and very flexible.
• High security of control as all functions
are distributed.
Disadvantages
• Greater cost due to its large capacity.
• Local plant equipment must be protected
in safe enclosures.
13. Introduction
• Step wise & Batch Process,
• Whole production process to become continuous and
automated, while keeping the advantage of flexibility, batch size
variation, and low cost.
• A continuous process is one in which,
Incoming material are fed automatically into one
process after being automatically transported from the
previous process;
Processed materials are automatically removed from one
process and automatically transported to next process;
Manufacturing operation is performed automatically and
successively after the materials are delivered to the machine.
14. Automation in solid dosage forms
We take two most widely used solid dosage forms,
1) Automation in tablet manufacturing &
2) Automation in Capsule manufacturing
15. Automation in tablet manufacturing
It is a batch and continuous process
Examples of continuous process:
→Tableting,
→Filling,
→ Filtration,
→ Packaging,
→ Inspection with use of instruments,
→ Distillation.
Examples of Batch process:
→ Weighing of raw materials,
→ Mixing,
→ Granulating,
→ Coating.
16. A. Continuous transfer of materials:
Material transportation is one of the most important operations in
pharmaceutical manufacturing and can be easily accomplished by AGVs,
conveyer belts or pneumatic tubes (transported by pipe, aided by air
system), robotics. There are two technologies for automated material;
handling, as follows
AGVs: - (Automated Guided Vehicles)
It is a small, driverless, battery-driven truck that moves materials between
operations, following instructions from either an onboard or a central
computer. Older models follow a cable installed below the floor, but the
newest generation follow optical path that can go anywhere with aisle space
and smooth floor. The AGV’s ability to route around problems such as
production, bottlenecks and transportation blockage helps production avoid
expensive, unpredictable shut down
Automated Storage and Retrieval System (AS/RS):-
An Automated Storage and Retrieval System is a computer control method of
storing and retrieving materials and tools using racks, bins and stackers. By
the help of AGV, AS/RS can retrieve and deliver material without aid of human
hands.
17. Automated tablet manufacturing process:-
In this system, all stages from granulation to coating are connected by pipes and
tanks. The entire operation is carried out automatically in this closed system. The
main operation of tablet manufacturing process can be divided into three kinds of
operations:
•Mixing and Granulation,
•Tableting,
•Coating.
Outline of the process:-
In the system shown in figure is process connected by pneumatic tube through
which in-process materials are transported to next process by vacuum or air
process.
18. Figure below shows an outline of the process flow through the computer
display panel or television camera in the central room. The status of
above three operations can be observed and controlled.
Outline of the process flow.
19. Operation Control:-
The status and condition of manufacturing operation can be observed by a
person in a central control room. If there are any abnormalities or deviation
from the standard conditions, they are displayed on the control panel, and any
necessary actions are printed out and indicated automatically or manually,
depending upon their nature.
If there is a critical problem, the machine is stopped automatically. In the case of
minor problem, an audio-visual sign appears on screen until the proper action has
been taken.
20. Tablet Weight Control:-
In continuous automated tablet manufacturing system, some major items of the
process are monitored and controlled automatically. Tablet weight control and
the punching pressure control systems are continuously monitored, based on
proper relationship, and a control chart is shown on the screen.
Fig. is given below, shows the automatic control mechanisms of tablet weight
and punching pressure;
1. The upper and lower limits are previously specified and input as the master
program.
2. Punch pressure is preliminarily set.
3. The requisite number of tablets taken is counted and weighed automatically.
4. On the basis of operational data, the relationship between tablet weight and
punching pressure is calculated in the continuous processing unit.
5. The calculated relationship is fed back into the load cell and punching
pressure controller to obtain the desire tablet weight previously set.
22. AFMAT (Automatic Feeding, Mixing & Tableting Machine):-
• A more than 200- hour nonstop automated tablet manufacturing
system has been recently completed by Japanese firm. In this
system, the feeding of granules and tableting are automatically
carried out continuously for 200 hours.
• The most difficult problems in automating pharmaceutical
manufacturing is successfully automating the connection between
the unit process to unit processes.
• Air system is applied to the transportation from unit process to
unit process of powders solid material; however often air transfer
system cause separation of the mixed powders.
• In order to solve the problem, other approach to combine several
unit functions (for example mixing, granulation and drying) to one
unit process has been taken.
• The AFMAT is one unit process system; the mixing operation is
performed by a rotatory stirrer. This allows the powder to be mixed
in a small and closed space without any separation.
23. An outline of the AFMAT.
Drug A is supplied to the hopper 1 by air and then to the hopper for weighing 2
by the weighing fedder 3. The exact amount of powder weight 2 is transferred
to the mixing hopper 5 in which drug A informally mixed with exact amount of
drug B.
24. • After drug A and B are uniformly mixed by the stirrer for a
previously specified period. The mixer of drug A and B are fed
through the hopper for mixer 5 & 6 and the constant feeder 7 to
the tableting machine 8. All of these operations are automated
and carried out continuously without the aid of any operators.
• After 24 hours, the powder corresponding to the former lot
(which remains in the hopper) and the new powder are mixed
for only a short period. However, the tablet is made from this
mixed powder are automatically eliminated. So there are no
tablets containing a mixer of powders from two different lots.
25. Automated capsule manufacturing process: -
Automatic Capsule Filling Machines: -
After blending, drug and empty capsules are pored into
separate feeder of filling machine. In this machine, filling,
locking and polishing are taken place. After getting filled
capsules they are sent to packaging department.
26.
27. The functions of first
station include capsule
feeding, aligning and
insertion into bores of
holding ring. Also, vacuum
is used for separating
capsule cap and body in
first station. After
orientation of capsule,
capsule cap can stay in
upper holding ring and
capsule body can stay in
lower holding ring.
There are 3 stations in this
capsule-filling machine
THE FIRST
STATION:ORIENTATION OF
CAPSULE
28. THE SECOND STATION:
POWDER FILLING
Separate the holding ring,
put the lower (body)
holding ring on the rotary
table, pull the powder
hopper over the lower
(body) holding ring, then
auger inside powder
hopper starts to run and
fill powder into the
capsule body. While I
owner holding ring turns
one circle, push powder
hopper to its original
position
29. THE THIRD STATION:
CAPSULE CLOSING
Put upper holding ring and lower
holding ring together, then take
the holding ring ahead of ejector
and aim ejector at the bores of
holding ring. Use hydraulic
cylinder to push ejector and let it
press capsules for closing. Finally
push capsules inside the bores of
holding ring out, the finished
capsules will be collected into the
container.
31. Soft Gelatin Encapsulation Machine:-
KDE-300 Fully Automatic Soft Gelatin Encapsulation
Machine is the most popular Soft Gelatin Capsule making
machine in the world; and more than 90% of soft gelatin
capsules in the world are produced by this kind of machine,
which had been modified by QUI techniques and
experiences to the KDE-300.
The features of the machine are:
1. All parts and components in contact with gelatin ribbon
and medical solutions are made stainless steel or
chrome plating.
2. Gelatin ribbon making and filling with sealing operation
can be completed on the same machine.
3. Step control for encapsulation machine
4. Easy for operatio6. Simple construction for maintenance.
5. High productivity.
6. Simple construction for maintenance easily.
32. PROCEDURE
The overall soft gelatin capsule
process starts from the gelatin that
is melted and de-bubbles via the
gelatin tank, then mixing formula
and color. Through the
encapsulation machine, the melted
gelatin solidify to the gelatin ribbon
which the medical solutions are
filled and sealed; then cutting,
formed into soft gelatin capsules.
The soft gelatin capsules send to
tumbler dryer via conveyor for
shaping. After that, carry to the
drying room for complete drying.
Finally, soft gelatin capsules can be
inspected and packed after the oily
stains are removed from surface
through the cleaning machine.