Manufacturing

1. Casting And It’s Industrial
Safety Measures

2. Realization Of The Importance Of Industrial Safety

3. • How Unsafe are Indian Workplaces?
• The accident statistics appeared under this title by Mr. N. Vidyasagar
in the ‘Business Times’ supplement of the Times of India.
• Around 125 workers die every day.
• 50,000 are injured every day.
• India accounts for 32% of global mishaps and 37% of occupational
injuries.
• This is a grave situation that should alarm us —as progressive thinkers
—and push us to investigate, in-depth, the causative factors
responsible for the present-day situation.

4. Safety Definition
• (Sir Brian Appleton);“Safety is not an intellectual exercise to keep us
in work rather it is a matter of life and death. It is the sum of our
contributions to safety management that determines whether the
people we work with live or die”
• Coined after the Piper Alpha mishap on 6 July 1988, killing 167 people

5. Bhopal Gas Tragedy
• The Union Carbide Corporation of USA established their Indian
The subsidiary, Union Carbide India Ltd. (UCIL), and a plant at Bhopal in 1934 to
manufacture carbaryl.
• Monomethylamine (MMA) + Phosgene Methyl Isocyanate (MIC)
• Methyl Isocyanate (MIC) + Alpha-Naphthol Carbaryl
• All over Europe the maximum permissible storage limit for MIC is observed as half
a ton.
• The U.S. management forced the managers of their Indian subsidiary to keep the
MIC storage capacity hazardously high at over 90 tons.
• MIC was thus stored in three large tanks at the Bhopal plant. This led to its
discharge in vapor and liquid form through the safety valve.

6. Bhopal Gas Tragedy: The Mishap
• 10:15 pm: The shift supervisor asked an operator to wash the piping
around one of the three MIC storage, suspecting a leak in the tank valve.
• The valve on the tank was blinded off to prevent ingress of water, entry
of which would initiate a highly exothermic polymerization reaction.
• 11:00 pm: The night shift operator noticed a pressure rise in the tank. He
ignored it on the assumption that it was pressurized in the previous shift
for the purpose of transferring the contents to the next pesticide unit.
• 11:30 pm: the operators sensed irritation in their eyes. They knew that it
was due to a small leak of MIC. Again, that was not an unusual
phenomenon to them, so they ignored it.
• Temperature and pressure continued to build in the MIC tank to several
times the permissible limit, irrespective of water being sprayed over.

7. Bhopal Gas Tragedy: Activities Led to Tragedy
• The catastrophe actually began when the storage tank of MIC became
contaminated with water and a runaway reaction occurred. The
temperature and pressure rose, the relief valve lifted and MIC vapour was
discharged into the atmosphere.
• The protective equipment, which should have prevented or at least
minimized the discharge, was out of action or not in full working order.
• The refrigeration system, which should have cooled the storage tank, was
shut down.
• The scrubbing system, which should have absorbed the vapour, was not
immediately available.
• The flare system, which should have burnt any vapour which got past the
scrubbing system, was out of use.

8. Bhopal Gas Tragedy: The Disaster
• At midnight, the undue pressure build-up in the tank burst the safety valve,
and MIC gas rushed straight through an atmospheric vent line out into
Bhopal’s cool night air in the early hours of Monday, December 3, 1984,
affecting innocent citizens and animals.
• Many people died in their sleep because of the heavy gas cloud, others
woke up to intense irritation in their eyes, choking, and suffocating
sensations in their throats and lungs. They rushed out onto the streets,
gasping for fresh air, only to make matters worse for themselves.
• Over 8000 people died in the immediate aftermath. About 250,000 were
left with permanent disabilities.
• Since then 10 to 15 persons die every month and over 120,000 continue to
suffer acutely from exposure-related diseases and their complications.

9. Bhopal Gas Tragedy: The Errors Committed
1. Adequate in-built safety systems were not provided and those provided
were not checked and maintained as scheduled.
2. In all, five safety systems; Vent gas scrubber, Flare stack, Water curtain,
A refrigeration system and spare storage tank were provided in the plant.
But none of these ever worked or came to the rescue in the emergency.
3. Safe operating procedures were not laid down and followed under strict
supervision.
4. Total lack of ‘on-site’ and ‘offsite’ emergency control measures.
5. No hazard and operability study (HAZOP) was carried out on the design and
no follow-up by any risk analysis.
6. Evacuation drills for fire and release of toxic gases were never held and
practiced.

10. Bhopal Gas Tragedy: The Errors Committed
7. The community living in the vicinity of the plant had never been
alerted and warned about the dangers.
8. The local authorities had never been informed of the hazards so they
would know what to do in the event of such an emergency.
9. It was the responsibility of both the local as well as central
authorities to request the management to disclose all the relevant
information with regard to the major hazard installations and their
control procedures, identifying key personnel responsible for taking
the appropriate measures in an emergency as per the provisions under
the Factories Act, 1948.
10. Danger signals and warnings were not observed and followed.

11. Bhopal Gas Tragedy: Lessons to be Learnt
1. Wherever and whenever possible, we should reduce or eliminate
inventories of hazardous materials, in process and in storage.
2. An alternative to intermediate storage is a substitution, i.e., using a safer
material or route, especially when reducing inventories, or intensification
as it is called is not practicable.
3. Just as “materials which are not there cannot leak”(Dr. Trevor Kletz),
“people who are not there cannot be killed”.
4. For major hazard installations like the Bhopal plant, a hazard, and
operability study (HAZOP) should be carried out on the design for
identifying routes by which contamination and other unwanted
deviations can occur.

12. Bhopal Gas Tragedy : Lessons to be Learnt
5. Keep protective equipment in working order and size it correctly,
even when the plant is shut down.
6. Safe Operating Procedures are to be maintained on a regular
schedule.
7. Training in Loss Prevention.
8. Handling ‘on-site’ and ‘offsite’ emergencies

13. CASTING
• Casting means pouring molten metal into a mold with a cavity of the
shape to be made and allowing it to solidify. When solidified, the
desired metal object is taken out from the mold either by breaking
the mold or taking the mold apart. The solidified object is called the
casting
• The mold, into which the metal is poured, is made of some heat-
resisting material.
• The sand is most often used as it resists the high temperature of the
molten metal.
• Permanent molds of metal can also be used to cast products.

14. Nomenclature of sand casting
•

15. Steps in making sand castings
(i)Pattern making,
(ii) Core making,
(iii) Moulding,
(iv) Melting and pouring,
(v) Cleaning

16. Foundry safety
• Foundry safety refers to ‘The management of all operations, and
events within a Foundry Industry, for protecting its employees and
assets by minimizing hazards, risks and accidents ’.
• The Foundry Industry is the most dangerous, Hazard prone industry
• Dealing with the foundry atmosphere is very difficult

17. Foundry safety
• Every company should train their workers how to deal with Hazards,
and provide them with proper 'Personal Protective Equipment(PPE)’.
• At the molding shop, molds are prepared. This work is a very dusty
job. Generally, molds are prepared with silica sand. The inhaling of
silica sand dust may cause a Lung disease, called 'Silicosis’.
• The Harmful rays produced during melting or Welding may cause
serious effects on our eyes and may cause Blindness.
• The noise produced at the EAF melting shop, Fettling and Machining
Shop is very dangerous for our Ears and may cause hard of Hearing.

18. Various types of hazards in a foundry industry
• Physical Hazard
• Respiratory Hazards
• Noise
• Fire and Explosions
• Eye Problem

19. Physical Hazards
• Physical hazards in foundry operation may be related to the handling
of large, heavy, hot raw materials, molten metal, and products
• Accident related to heavy mechanical transport.
• Injuries from grinding and cutting activities, maybe due to falls from
elevations.

20. Safety Measures For Physical Hazards
• Appropriate design and Layout of facilities to avoid crossover of
different activities and flow of the process.
• Material and Product handling should remain within a restricted zone
under supervision, with particular attention paid to the proximity of
electrical cables and equipment.
• Locate machine tools at a safe distance from other work areas and
from walkways.
• Conduct regular inspection and repair of machine tools, in particular,
protective shields and safety devices/equipment

21. Safety Measures For Physical Hazards
• Use appropriate PPE (Personal Protective equipment) such as
Helmets, Insulating gloves, safety shoes, goggles, and clothes.

22. Respiratory Hazards
• Dust generated in foundries includes iron and metallic dust, which are
present in melting, casting, and finishing shops; and wooden and
sand dust, which are present in the molding shop, which may cause
respiratory issues.
• Workers are exposed to iron oxide and silica dust that may be
contaminated with heavy metals such as chromium (Cr), nickel (Ni),
lead (Pb), and manganese (Mn).
• The fine particle size, and potential metallurgical fumes, create a
serious occupational inhalation risk.

23. Safety Measures For Respiratory Hazards
• Sources of dust and gases should be separated and enclosed.
• Use automated equipment, especially in the fettling process.
• Use of filter respirators when exposed to heavy dust (e.g. fettling
works).
• For carbon monoxide (CO) exposure, detection equipment should be
installed to alert control rooms and local personnel.
• In case of emergency intervention in areas with high levels of CO,
workers should be provided with portable CO detectors, and fresh-air-
supplied respirators.

24. Dust and Fumes Problem in Melting Shop (Image Source- BHEL.
Haridwar)

25. Noise Problem:
• The foundry process generates noise from various sources, including
scrap handling, furnace charging, EAF melting, fuel burners, shakeout
and mold/core shooting, and transportation and ventilation systems.

26. Safety Measures For Noise Problem
• Cover and enclose scrap storage and handling areas, as well as shake
out and fettling processes.
• Above 85 dB noise level hearing protector should be worn by workers

27. Fire and Explosions
• Handling of liquid metal may generate a risk of explosion, melt run
out, and burns, especially if humidity is trapped in enclosed spaces
and exposed to molten metal.
• Other hazards include fires caused by molten metal and the presence
of liquid fuel and other flammable chemicals.
• In addition, iron foundry slag may be highly reactive if calcium carbide
is used to desulfurize the iron.

28. Safety Measures For Fire and Explosions
• Design facility layout to ensure adequate separation of flammable gas
and oxygen pipelines, and storage tanks, away from heat sources.
• Protect flammable gas and oxygen pipelines and tanks during "hot
work' maintenance activities;
• Emergency preparedness and response.
• Explosions may take place if the molten metal gets contact with the
water or Moist atmosphere.
• Mandatory Wearing of Personal Protective Equipment such as Safety
Clothing, Safety shoes, Hand Gloves, etc.
• Mandatory Placement of Fire Extinguishers in the industry

29. Eye Problem
• Some of the dust and chemicals encountered in foundries (e.g.,
isocyanides, formaldehyde, tertiary amines, and so on) are irritants
and have been responsible for visual symptoms among exposed
workers.
• These include itchy, watery eyes, hazy or blurred vision, or, so-called
“blue-grey vision”

30. Safety Measures For Eye Problem
• Wash your eyes immediately every time when you are exposed to a
dusty and chemically polluted atmosphere.
• Wear safety goggles every time inside the Plant.
• The company should provide an 'Emergency Eyewash section' near
the dusty area inside the plant.