COMPANY INTRODUCTION

1
CASE STUDY
ENERGY CONSERVATION OPPORTUNITIES at A Foundry
at Bhiwadi (Rajasthan)
2
COMPANY INTRODUCTION
MANUFACTURING GATE , GLOBE AND FLAP VALVES OF
SIZES 1.5 TO 20 AND TURBINE PARTS SUCH AS
CASING TOP / BOTTOM, HORSE SHOE, ETC. MOC CAST
STEEL / SS ANNUAL PRODUCTION 600 TONNE ANNUAL
ENERGY CONSUMPTION FUEL 48 KL ( LDO HSD AND
FO) ELECTRICITY 9.65 LAKH UINTS SPECIFIC POWER
CONSUMPTION (TONNES / LAKH KWH) 62.17
3
STUDIES CARRIED OUT DURING AUDIT
ELECTRICAL INDUCTION FURNACE 500 KG (I
NO) HEAT TREATMENT FURNACE 250 KG (1 NO) MOTORS
10HP AND ABOVE (6 NOS) AIR COMPRESSOR 120 CFM
(2 NOS) ELECTRICITY BILL REVIEW THERMAL HEAT
TREATMENT FURNACE 3.5 TONNE (1 NO) LADDLE PRE
HEATING
4
SUGGESTIONS FOR IMPROVEMENT

• ELECTRICAL
• INDUCTION FURNACE
• MOLTEN METAL THAT REMAINS IN THE LADDLE, AFTER
  CASTING, SHOULD BE RE-POURED BACK INTO THE
  FURNACE WHENEVER POSSIBLE
• THE ABOVE PRACTICE CAN SAVE RE-MELTING OF AT
  LEAST 80 KG OF IRON PER DAY THIS AMOUNTS TO
  ANNUAL SAVING OF RS.49,000/-
• INSTALL ENERGY METER EXCLUSIVELY FOR THE FURNACE
  AND THE DATA SHALL BE RECORDED IN THE LOG BOOK
  FOR EVERY HEAT. BY DOING SO THE ELECTRICAL ENERGY
  CONSUMED PER HEAT CAN BE MONITORED FOR REDUCING
  IDLE TIME
• SEPARATE POWER FACTOR INDICATOR TO BE INSTALLED,
  FOR MONITORING OF POWER FACTOR OF THE FURNACE,.
  THIS WILL ENABLE TO IMPROVE THE POWER FACTOR
• AVERAGE ELECTRICITY CONSUMED PER HEAT IS 240
  UNITS (KWH) FOR MELTING 500 KG OF METAL i.e.
  0.48 UNITS PER KG

5
SUGGESTION FOR IMPROVEMENT

• ELECTRICAL
• THE LOADING OF FURNACE TAKES ABOUT 1 HR AS THE
  RAW MATERIAL IS PRIMARILY SCRAP OF UNEVEN
  SIZES.THIS TIME CAN BE REDUCED IF IT CAN BE FED
  IN FORM OF BUNDLES , ESTIMATED SAVING IN TIME
  WILL BE ABOUT 10 RESULTING IN SAVING OF RS 2.45
  LAKHS PER ANNUM (BASED ON 8 HEATS A DAY AND 300
  WORKING DAYS)
• HEAT TREATMENT FURNACE
• THE TEMPERATURE OF THE MATERIAL AFTER QUENCHING
  AND NORMALIZATION SHOULD NOT BE ALLOWED TO GO
  BELOW 150C SO AS TO MINIMIZE HEATING TIME DURING
  TEMPERING IN THE NEXT CYCLE. THIS WILL REDUCE THE
  CYCLE TIME AND POWER CONSUMPTION BY 16 KWH PER
  DAY RESULTING IN ANNUAL SAVING OF Rs.20,000/-

6
SUGGESTION FOR IMPROVEMENT

• ELECTRICAL
• ONLY HALF CAPACITY OF THE FURNACE IS USED DUE TO
  LESS QUANTITY OF OIL IN THE QUENCHING TANK. BY
  INCREASING THE OIL QTY IN THE QUENCHING TANK FULL
  CAPACITY OF THE FURNACE CAN BE UTILIZED THIS WILL
  SAVE 45 KWH PER DAY RESULTING IN SAVING OF Rs
  57,500/- P.A.
• IT WAS FOUND THAT MATERIAL BEING NORMALIZED BY
  NATURAL COOLING IS ALSO BEING TEMPERED AT 520C.
  AFTER DISCUSSIONS WITH THE TECHNICAL PERSONNEL IT
  WAS DECIDED TO DISCONTINUE THIS PRACTICE AS IN
  THEIR VIEW TEMPERING IS NOT REQUIRED FOR A
  NORMALISED PRODUCT. (THIS PRACTICE WAS WRONGLY
  STARTED WITHOUT THE KNOWLEDGE OF HIGHER
  MANAGEMENT). THIS WILL SAVE 17 KWH PER BATCH OF
  400 KG MATERIAL.

7
SUGGESTION FOR IMPROVEMENT

• ELECTRICAL
• MOTORS
• THE PERCENTAGE LOADING OF SHOT BLASTING MOTORS (2
  NOS) IS AROUND 17. THE EXISTING 10 HP MOTORS CAN
  BE REPLACED BY AVAILABLE 5 HP MOTORS. THIS WILL
  IMPROVE EFFICIENCY AND POWER FACTOR OF THE
  MOTORS. NOT ONLY SAVING OF AROUND RS 11500 PER
  ANNUM CAN BE ACHIEVED BUT ALSO THE MOTORS OF 10
  HP AND ITS STAR-DELTA STARTER SWITCH GEAR CAN BE
  UTILIZED ELSEWHERE
• ALL THE 5 BELTS SHOULD BE PROVIDED ON THE
  COUPLING BETWEEN MOTOR AND COMPRESSOR. THE BELTS
  USED AS THE POWER TRANSMISSION MECHANISM SHOULD
  BE TIGHT.
• THE WORKING ENVIRONMENT BEING DUSTY, MOTOR
  SHOULD BE CLEANED IN EVERY SHIFT TO INCREASE
  THEIR EFFICIENCY

8
SUGGESTION FOR IMPROVEMENT

• ELECTRICAL
• AIR COMPRESSOR
• THE CFM OF C-2 WAS FOUND TO BE 74 CFM WHERE AS
  THE RATED CFM IS 120(61). OVER HAULING OF THE
  COMPRESSOR AND REGULAR SUCTION AIR FILER
  CLEANING SHALL IMPROVE IT
• THE LEAKAGE IN THE SYSTEM WAS EXTREMELY HIGH. AS
  A RESULT OF WHICH THE COMPRESSORS IS NOT GETTING
  UNLOADED DURING LEAKAGE TEST FOR 30 MINUTES. THIS
  INDICATES 100 LEAKAGE IN THE AIR SYSTEM. DUE TO
  LEAKAGE, THE PRESSURE AT THE UTILITY IS NOT
  SUFFICIENT AND IT IS REQUIRED TO RUN THE 2ND
  COMPRESSOR. HENCE THERE IS A LEAKAGE OF ABOUT 74
  CFM AND A POTENTIAL OF SAVING RS 2 LAKH PER ANNUM
• WHENEVER COMPRESSOR IS RUN ON NO LOAD, SAVING OF
  17 KW IS ACHIEVED. IF LEAKAGES ARE ATTENDED,
  RUNNING OF 2ND COMPRESSOR CAN ALSO BE AVOIDED
• PREFERABLY FLAT BELTS TO BE USED IN PLACE OF
  V-BELTS

9
SUGGESTION FOR IMPROVEMENT

• ELECTRICAL
• ELECTRICITY BILL REVIEW
• THE AVERAGE POWER FACTOR OF THE INSTALLATION IS
  0.93. THE REBATE STARTS FROM 0.95 AND ABOVE.
  THERE IS A POTENTIAL SAVING OF Rs 2 LAKH PER
  ANNUM BY MONITORING P.F. OF FURNACE AND
  ACCORDINGLY INSTALLING SUFFICIENT CAPACITOR BANK
• IMPROVEMENT IN POWER FACTOR SHALL REDUCE CURRENT
  REQUIREMENT AND CONSEQUENTLY THE MAXIMUM DEMAND
  SHALL REDUCE WHICH WILL REDUCE THE FIXED CHARGES
  (_at_ 90/KVA) AND THERE IS POTENTIAL OF SAVING RS
  26,000 P.A

10
SUGGESTION FOR IMPROVEMENT

• THERMAL
• HEAT TREATMENT FURNACE
• FURNACE OIL TEMP AT MAIN STORAGE, PREHEATING TANK
  AND BURNER WERE FOUND 38, 45 AND 35C
  RESPECTIVELY. THIS WILL RESULTS IN POOR FUEL
  AUTOMISATION AND FORMATION OF EXCESS CO IN FLUE
  GAS. THIS IS DUE TO ABSENCE OF SERVICE TANK AND
  INSUFFICIENT FUEL TEMPERATURE. BY INSTALLING
  SERVICE TANK WITH HEATER BETWEEN MAIN STORAGE
  TANK AND PREHEATING TANK. TEMPERATURE CAN BE
  MAINTAINED AT 45, 80 AND 110 C AT MAIN STORAGE,
  SERVICE TANK AND PRE-HEATER TANK RESPECTIVELY AND
  ALSO THE ABOVE LINE AND FUEL TANK TO BE PROPERLY
  INSULATED
• HIGH EXCESS AIR OF 140 WAS MEASURED IN FLUE
  GASES DUE TO ABSENCE OF ANY AIR CONTROL MECHANISM
  FOR AIR SUPPLY

11
SUGGESTION FOR IMPROVEMENT

• THERMAL
• BY REDUCING EXCESS AIR LEVEL FROM 140 TO 30
  SAVINGS OF 5 KL OF FURNACE OIL PER ANNUM CAN BE
  ACHIEVED.
• LADDLE PREHEATING
• PRESENTLY COMPRESSED AIR IS BEING USED AS
  COMBUSTIBLE AIR SINCE THE BLOWER IS OF SMALLER
  CAPACITY. SO, REPLACEMENT OF EXISTING BLOWER OF
  2 HP WITH 5 HP OF 400 CFM AND 40 OF WG WILL
  RESULT IN SAVING OF 1.2 KL P.A.