COST REDUCTION INHEAT TREATMENT BY USING PROTECTIVE COATINGS                              byS.P. SHENOY - C.E.O.      and ...
PART IIntroduction.Losses   due to Oxidation.Methods   of Preventing Oxidation.Protective   Coating to Reduce Costs in...
   Importance of Heat Treatment   It can either add further value to the already    value - added component, or    gener...
OXIDATIONGeneral reactions:O2    + 2 Fe   ⇌     2 FeOO2    + 4 FeO ⇌      2 Fe2O3CO2 +     Fe   ⇌     CO + FeO      + 3 Fe...
LOSSES DUE TO OXIDATION1. Loss of dimension and material.2. Deterioration of surface quality, i.e., pitting.3. Non-uniform...
PREVENTING OXIDATION1. Copper plating prior to heat treatment.3. Use of molten salt bath as heating media.4. Use of protec...
PREVENTING OXIDATION                              COATING         METAL                     AIR                           ...
Characteristics of ESPON    Anti Scale Protective CoatingDoes   not react with metal.Does not give any toxic fume during...
PART IISuccessful Case Studies
Coated Billets before Hot Forging Coated Componentsbefore Heat Treatment
Table-1 Efficacy of Protective CoatingType of furnace used           : Box type, electric.Test Coupon dimensions         :...
NOT COATED   COATED
COATED   NOT COATED
Benefits of using protective coatings:1.Elimination or minimization of post heat treatmentoperations like grinding, shot b...
Use of Protective Coating           To Eliminate Or Minimize  Post Heat Treatment    Operations Like      Shot Blasting,Gr...
Protective Coating to Prevent ScalingNOT COATED                     COATED
CONVENTIONAL METHOD                  USE OF COATING       HOT FORMING                      HOT FORMINGELBOW, TEE, REDUCER,...
Minimizing scaling during hot rolling of AISI 416grade stainless steel.Problem: excessive scaling during re-heating ofbill...
Protecting Critical Areas during Heat Treatment
Coated Split Rings before Heat Treatment.Super Duplex Stainless Steel. Investment Castings.
After Heat Treatment & Shot Blasting.(1200 Deg. C. / 4 hrs. / water quenched)
PRODUCTIVITY IMPROVEMENT DUE TO COATING        STEEL PLATES                             STEEL PLATES            ANNEAL    ...
SCALE PREVENTION = MATERIAL SAVING + PRODUCTIVITY IMPROVEMENT             CR Sheets                       CR Sheets      4...
Preventing scaling on the inner surface of Forged Spindles                                   Smooth inner surface         ...
Use of Protective Coating            To  Reduce Decarburization,Ensure Uniform Hardness andIncreased Fatigue Life of leaf ...
COATED ANDHEAT TREATED.                NOT COATED AND                HEAT TREATED.
COATED ANDHEAT TREATED.                NOT COATED AND                HEAT TREATED.
Use of Protective Coating          To  Prevent Or Minimize   Rejections due to   Quench Cracking
Minimising rejections due to quenchcracking:            Product: Steering knuckle                      Quench crack       ...
Gear-end of crank shafts prone to quench cracks
Use of Protective Coating                   ToSalvage rejected components by re-heattreatmentIncrease yield during re-work...
REJECTED COMPONENTS     (HEAT TREATED)(METALLURGICAL REASONS)                SALVAGE BYSCRAP        RE-HEAT TREATMENT     ...
Re-Heat Treatment of Finish Machined Forged SpindlesImage on left shows heat treated spindles. Image on Right shows a re-h...
Heavy scaling leads to pit-marks on forgings during re-working.
Scale-pits are prevented by use of anti-scale coating during re-work.                  Identification numbers are intact.
SUMMARY Use of protective coating has established itself asan effective technique in the area of Heat Treatmentwith refer...
Thank you !   Tel. : 91-22-6797 8060 Fax : 91-22-2555 2459 Email : info@steelplantspecialities.comWebsite : www.steelplant...
Cost Reduction In Heat Treatment, Hot Rolling and Hot Forging by the use of Protective Coatings
Cost Reduction In Heat Treatment, Hot Rolling and Hot Forging by the use of Protective Coatings
Cost Reduction In Heat Treatment, Hot Rolling and Hot Forging by the use of Protective Coatings
Cost Reduction In Heat Treatment, Hot Rolling and Hot Forging by the use of Protective Coatings
Upcoming SlideShare
Loading in …5
×

Cost Reduction In Heat Treatment, Hot Rolling and Hot Forging by the use of Protective Coatings

1,916 views
1,618 views

Published on

This presentation outlines an innovative concept to reduce cost in heat treatment, hot rolling and hot forging. Industrial case studies and photos are included.

Published in: Technology
1 Comment
0 Likes
Statistics
Notes
  • Be the first to like this

No Downloads
Views
Total views
1,916
On SlideShare
0
From Embeds
0
Number of Embeds
34
Actions
Shares
0
Downloads
68
Comments
1
Likes
0
Embeds 0
No embeds

No notes for slide

Cost Reduction In Heat Treatment, Hot Rolling and Hot Forging by the use of Protective Coatings

  1. 1. COST REDUCTION INHEAT TREATMENT BY USING PROTECTIVE COATINGS byS.P. SHENOY - C.E.O. and SRIKAR SHENOY – G.M. 211, RAIKAR CHAMBERS, GOVANDI EAST, MUMBAI–400 088. INDIA. Tel. : 6797 8060 Fax : 2555 2459 Email : info@steelplantspecialities.com Website : www.steelplantspecialities.com
  2. 2. PART IIntroduction.Losses due to Oxidation.Methods of Preventing Oxidation.Protective Coating to Reduce Costs in HT. PART IISuccessful Case Studies.Summary
  3. 3.  Importance of Heat Treatment It can either add further value to the already value - added component, or generate scrap due to oxidation / scaling.
  4. 4. OXIDATIONGeneral reactions:O2 + 2 Fe ⇌ 2 FeOO2 + 4 FeO ⇌ 2 Fe2O3CO2 + Fe ⇌ CO + FeO + 3 FeO ⇌ Fe3O4 + COCO2
  5. 5. LOSSES DUE TO OXIDATION1. Loss of dimension and material.2. Deterioration of surface quality, i.e., pitting.3. Non-uniform metallurgical transformation during hardening.4. Lowered surface hardness and strength.5. Reduced fatigue life of heat treated product. General practice:Removal of oxidized or decarburized layer by machining operations after heat treatment.
  6. 6. PREVENTING OXIDATION1. Copper plating prior to heat treatment.3. Use of molten salt bath as heating media.4. Use of protective atmospheres.5. Use of vacuum furnace.6. Switching over to grades not requiring HT. or7. Use of protective coatings.
  7. 7. PREVENTING OXIDATION COATING METAL AIR Oxidation is either prevented or delayed.Impact of the coating onscaling mechanism.
  8. 8. Characteristics of ESPON Anti Scale Protective CoatingDoes not react with metal.Does not give any toxic fume during use or during heating the coated job.Non-hazardous.Economical. Method of application: Brushing, Dipping or Spraying
  9. 9. PART IISuccessful Case Studies
  10. 10. Coated Billets before Hot Forging Coated Componentsbefore Heat Treatment
  11. 11. Table-1 Efficacy of Protective CoatingType of furnace used : Box type, electric.Test Coupon dimensions : 300mm X 100mm X 10mmGrade of steel : AISI – 1010Heat treatment cycle : 1000° C / 4 hrs / air cool% scale loss when not coated : 5.52% scale loss when coated : 0.70
  12. 12. NOT COATED COATED
  13. 13. COATED NOT COATED
  14. 14. Benefits of using protective coatings:1.Elimination or minimization of post heat treatmentoperations like grinding, shot blasting or acidpickling.2. Reducing decarburization – uniform hardness andmechanical properties. Increased fatigue life.3. Preventing rejections due to quench cracking.4. Salvaging rejected components by re-heattreatment. Increasing yield during re-working ofrejected forgings.
  15. 15. Use of Protective Coating To Eliminate Or Minimize Post Heat Treatment Operations Like Shot Blasting,Grinding, Or Acid Pickling.
  16. 16. Protective Coating to Prevent ScalingNOT COATED COATED
  17. 17. CONVENTIONAL METHOD USE OF COATING HOT FORMING HOT FORMINGELBOW, TEE, REDUCER, CAP, ELBOW, TEE, REDUCER, CAP,STUB END, RETURN BEND STUB END, RETURN BENDGRADES : AISI – 304, 304L, GRADES : AISI – 304, 304L, 316, 316L, 316, 316L, 321, 321H, 321, 321H, 347, 347H 347, 347H SOLUTION ANNEALING SOLUTION ANNEALING PICKLING TIME IS REDUCED BY 75% PICKLING PICKLING BUFFING CAN BE ELIMINATED IN MANY BUFFING CASES. HENCE QUICKER DELIVERIES INSPECTION INSPECTION SHIPPING SHIPPING BENEFITS OF USING COATING IN PROCESSING OF STAINLESS STEEL PIPE FITTINGS
  18. 18. Minimizing scaling during hot rolling of AISI 416grade stainless steel.Problem: excessive scaling during re-heating ofbillets mainly due to higher sulfur content.Solution: Protective coating minimizes scaling inre-heating furnace.
  19. 19. Protecting Critical Areas during Heat Treatment
  20. 20. Coated Split Rings before Heat Treatment.Super Duplex Stainless Steel. Investment Castings.
  21. 21. After Heat Treatment & Shot Blasting.(1200 Deg. C. / 4 hrs. / water quenched)
  22. 22. PRODUCTIVITY IMPROVEMENT DUE TO COATING STEEL PLATES STEEL PLATES ANNEAL ANNEAL AFTER ESPON COATING SHOT BLAST SHOT BLAST SHOT BLAST SHOT BLAST DESPATCH DESPATCHAbove Details as confirmed by M/s. SAIL, Rourkela Steel Plant, Rourkela.
  23. 23. SCALE PREVENTION = MATERIAL SAVING + PRODUCTIVITY IMPROVEMENT CR Sheets CR Sheets 4300 mm X 1100 mm X 4.5 mm 4300 mm X 1100 mm X 4 mm USE PROTECTIVE COATING ANNEALING ANNEALING 950ºC/30 mins./ 950ºC/30 mins./ air-cool to room temperature air-cool to room temperature HOT LEVELLING HOT LEVELLING 820ºC/60 mins. 820ºC/60 mins. GRINDING REDUCED BY 50% GRINDING FINAL THICKNESS FINAL THICKNESS 3.7 mm 3.7 mm
  24. 24. Preventing scaling on the inner surface of Forged Spindles Smooth inner surface after coating and heat treating.
  25. 25. Use of Protective Coating To Reduce Decarburization,Ensure Uniform Hardness andIncreased Fatigue Life of leaf springs.
  26. 26. COATED ANDHEAT TREATED. NOT COATED AND HEAT TREATED.
  27. 27. COATED ANDHEAT TREATED. NOT COATED AND HEAT TREATED.
  28. 28. Use of Protective Coating To Prevent Or Minimize Rejections due to Quench Cracking
  29. 29. Minimising rejections due to quenchcracking: Product: Steering knuckle Quench crack 3% reduced to less than 0.5%
  30. 30. Gear-end of crank shafts prone to quench cracks
  31. 31. Use of Protective Coating ToSalvage rejected components by re-heattreatmentIncrease yield during re-working of rejectedforgings.
  32. 32. REJECTED COMPONENTS (HEAT TREATED)(METALLURGICAL REASONS) SALVAGE BYSCRAP RE-HEAT TREATMENT USING PROTECTIVE COATING
  33. 33. Re-Heat Treatment of Finish Machined Forged SpindlesImage on left shows heat treated spindles. Image on Right shows a re-heat treated spindle. Aesthetic appeal is intact. Zero Scaling.
  34. 34. Heavy scaling leads to pit-marks on forgings during re-working.
  35. 35. Scale-pits are prevented by use of anti-scale coating during re-work. Identification numbers are intact.
  36. 36. SUMMARY Use of protective coating has established itself asan effective technique in the area of Heat Treatmentwith reference to preventing scaling anddecarburisation.
  37. 37. Thank you ! Tel. : 91-22-6797 8060 Fax : 91-22-2555 2459 Email : info@steelplantspecialities.comWebsite : www.steelplantspecialities.com

×