Material for Plant construction (Pharmaceutical Industry) l Study Pharma l
- Selectivity of material
- Design of equipment
- Technique of fabrication
- Resistance to physical shock i.e, Operating stress
- Resistance to thermal shock i.e, Operating temperature
- Ease of fabrication
- Strength
- Cost
- Maintenance
Factors affecting the Selection of material for construction:
1. Chemical factor
2. Physical factor
1. Chemical factor:
When we use a container to store a content and the content in the container interact or react with the material of the container or damage the container to get contaminated.
2. Physical factor:
Physical factor affect the physical properties of the material that we are using for construction of equipment such as
- Strength
- Wear properties
- Mass
- Thermal conductivity
- Thermal expansion
- Ease of fabrication
- Cleansing
- Sterilization
- Transparency
- Strength:
Material that we are use for construction of equipment should be high strengthen in nature so that it able to withstand on high stress or loads.
Example: Iron and Stainless steel are fulfill all these requirements.
- Wear properties:
Material that we are use should not produce friction on movable parts to loss surface smoothness.
Example: In mill and grinding machines, at working the surface of the mill get wear off due to friction and cause contamination in the product. It should be avoided.
- Mass:
The equipment should be light in weight and satisfy all factors so that easy to transport from one place to another place.
Example: Glass and Plastics are used in pharmaceutical industries for the handling and packaging of products and transportation easily.
- Thermal conductivity:
Thermal conductivity of the materials are depends upon the category of equipment that use for the manufacturing of different products.
Example:
Material that use in evaporator such as steam pan
Outer sheet material has low conductivity. (Iron)
Inner sheet has high conductivity. (Copper)
- Thermal expansion:
Material that used should not expand on high temperature to permanently deformation. It should be stable to configure its original structure (shape and size).
Example: Lead material not good because it get deform itself on high temperature. So that we replace lead from iron or any other material which has little or no thermal expansion.
- Ease of fabrication:
Materials undergo various process such as casting, welding, forging, mechanization and etc.
Example: Iron and Steel are used.
- Cleansing & Sterilization:
Materials are used to make equipment should be having smooth surface and not much complicated structure. So that easy to clean. and sterilization.
- Transparency:
Some materials like glass and plastics are used which provide transparency that permit the visual observation of changes in the product.
Example: Borosilicate glass used in reactor, fermentors, etc.
Classification of Materials for Plant Construction:
Materials are used that includes
- Metals
- Non metals
- Metals:
Metals are solid materials which are hard, shiny, malleable, ductile, good conductor of heat as well as electricity.
Example: Iron, Gold, Silver, etc.
Metals are divided into two types:
- Ferrous (which contain iron)
- Non ferrous (which do not contain iron)
-Ferrous are of further three types:
1. Cast iron
2. Carbon steel
3. Stainless steel
1. Cast iron:
Cast iron consists of iron and proportion of carbon beyond 1.5 %. It is easily available, inexpensive, abundant, Mechanical strength.
Advantages:
- Cast iron is cheap so that used in lining of equipment.
-Resistance to Conc. H2SO4,HNO3.
- It has low heat conductivity, used as outer lining of steam jacket.
Disadvantages:
- It is hard and brittle, difficult to machine.
- Affected by dilute H2SO4,HNO3 and dilute as well as conc. HCl.
- It cannot used for heat transfer.
Uses:
- Support for plant.
- Used as a lining of steam jacket.
Alloy of Cast iron:
- Grey cast iron:
Composition: carbon and silicon
Properties: Cheap, resistance to corrosion, easy to cast.
Disadvantages: Brittle, poor resistance to impact and shock.
- Malleable iron:
Composition: White cast iron and carbon 2-5%
Properties: Resistance to corrosion, easy to machine.
Disadvantages: One time machined material do not undergo again machine.
- High silicon cast iron:
Composition: Silicon conc. 13-16% in cast iron.
Properties: Resistance to corrosion, used in redox condition, resist to H2SO4.
Disadvantages: Not easy to machine.
2. Carbon steel (Mild steel):
Carbon steel is an iron alloy which contains iron and small amount of carbon in it.
Advantages:
- It is cheapest.
- It is easily welded and used in fabrication.
Disadvantages:
- It has limited resistance to corrosion.
-It react with caustic soda, brine, sea water.
(Improve its alloying reduce its disadvantages)
Uses:
Carbon steel used in the construction of pipes, bars, plates used in the fabrication of tanks and in supporting structures.
Alloy of Carbon steel:
- Low alloy steel:
Composition: Low Fe, C, Mg, Ni, Cr concentration.
Advantages: High strengthen, resistance to corrosion.
Disadvantages: Low machinability, weldability, formability.
- Alloying with nickel:
Composition: Nickle.
Advantages: High strengthen, resistance to corrosion
Disadvantages: Effect of Oxidizing agent
- Alloying with silicon chromium:
Composition: Nickel with chromium
Advantages: Resist to corrosion and oxidation
3. Stainless steel:
Stainless steel is an alloy of iron which contains Chromium, Nickel, Titanium, Niobium, Tantalum and add small amount of Copper, Molybdenum, Selenium.
Advantages:
- Heat resistance
- Resist corrosion
- Ease of fabrication
- Easy cleaning and sterilization
- high strengthen
Alloy of stainless steel:
- Martensitic:
Composition: Chromium 12-20%, Carbon 0.2-0.4%, Nickel 2%
Advantages: Mild corrosion resistance of atmosphere and organic solvents
Disadvantages: Poor ductility
Uses: Sinks, benches, buckets, mixing elements, storage tanks
- Ferritic:
Composition: Chromium 15-30%, Carbon 0.1%
Advantages: Better corrosion resistance, used in fabrication, prevent oxidation and temperature (up to 800 degree C)
Disadvantages: Not used against reducing agents, Hydrochloric acid
Uses: Tower lining, baffles, heat exchangers, pumps, furnace, shaft
-Austenitic:
Composition: Chromium 13-20%, Nickel 6-22%, Carbon 0.1<0.25%
Advantages: High corrosion resistance, easily clean and sterilize, easy to weld and non-magnetic
Disadvantages: Not easy to machine
Uses: Fermentors, storage vessels, extraction vessels( funnels, buckets, etc.
- Non ferrous
1. Aluminium
2. Lead
1. Aluminium:
Aluminium is a non-ferrous substance which are used mostly in our daily life because of its adequate mechanical strength, cheap, easily available and abundant.
Advantages:
2. Lead:
- Non-metals:
Non-metals are further two types;
1. Inorganic
2. Organic
1. Inorganic:
It further divided into;
1. Glass:
Various types of Glasses:
- Soft glass: (Soda glass)
Composition: Sodium silicate and calcium silicate.
Advantage of use: Making glass bulbs and windows, used in contact lenses.
- Hard glass: (Potash glass)
Composition: Potassium silicate and calcium silicate.
Advantage of use: Used as glass apparatus which resist acids.
- Flint glass: (Potash lead glass)
Composition: Potassium silicate and lead silicate.
Advantage of use: Used in optical instruments
THANKS TO ALL
Prepared by KKC
THEME: Study available for all only you need to understand and learn
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