Problem

India’s leading fully integrated steel plant in western region faced high temperature wear, abrasion, erosion and corrosion issues at its Sinter Plant (Cold and Hot Sinter Areas), Sponge Iron Plant, Blast Furnace.

1. Sinter plant- Sinter Breaker Hammers were experience rapid wear rates. Reversible Impact Crusher Hammers were supplied by an exiting vendor in low alloy steel with hardfacing of 2-3 mm done on the hammer head impacting area
2. Sponge Iron Plant- Has OEM Midrex DRI. The Lower Burden Feed (LBF) and Middle Feed Burden (MBF) Breaker Discs were suffering from rapid wear, abrasion and demanding frequent shut down (every 3 months) and replacement of breaker discs in 8-12 months of operation
3. Sinter Plant-Sinter Roll Crusher- Sinter Horn Teeth handling hot sinter at 800°C were experience high temperature corrosion, wear and abrasion including metal
   dusting and heavy metal loss as scaling
4. Blast Furnace- OEM Paul Wurth, Burden Roll Over Feeder Plate was experiencing high wear and abrasion rates due to falling burden feed and high service temperature, that required repair shut down in 6-8 months, with impacting feed making holes in the wear plate which were plugged with hardfacing material and repair plates.

Evaluation,Assessment, Recommendation And Solution(s)

ACME team visited the plant and made detailed evaluation of wear, corrosion and failures of at Sinter Plant, Blast Furnace, Sponge Iron Plant, Continuous Casting Plant and Plate Mill

1. Sinter Breaker Hammers for limestone and dolomite crushing ACME suggested manufacturing and supplying inter breaker hammers in ACME Modified Austenitic Manganese Steel (AMS) ASTM A 128 Grade E1 and E1, titanium killed in solution annealed condition. Supplied Hardness HRC 45-55 which improved in work hardened end condition to HRC 60+
2. Sponge Iron Plant- MIDREX Spares-Breaker Discs ACME manufactured and supplied Breaker Discs in ACME Modified ASTM A 297 HD Alloy in both toothed and plain breaker discs, reverse engineered from drawings and samples.
3. Sinter Plant- Sinter Roll Crusher Horn Teeth A detailed 50-page evaluation and case study report with recommendations were submitted to the management and plant operation team for solution to handle high temperature erosion and wear of sinter horn teeth- 52 nos. mounted on the sinter roll crusher shaft
4. Blast Furnace- Wear Plates for the Burden Roll Over Chute ACME Manufactured and supplied composite wear plates 4 no. to match the dimensions of the OEM Blast Furnace wear plate replacement part. The composite plates consisted of 12mm base plate of IS 2062: Grade B with 8 mm High Chrome Hardfacing (applied in two passes) using submerged arc welding technique

Result

1. ACME developed AMS ASTM A 128 Modified E1 and E2 reversible impact hammers outperformed the existing product being used at the Sinter Plant. Useful life of the hammers doubled before asking replacement. No hardfacing was required. More than 70% of hammer head was used in reversible impacting service conditions. Previously used hammer achieved 2500-3200 Metric Tonne of closed circuit crushing of limestone and dolomite while ACME products achieved much higher crushing tonnage. Grade E1 (1% Molybdenum) titanium killed one set of 52 hammers resulted in 8000-12000 Metric Tonne of crushing, while Grade E2 (2% Molybdenum) titanium killed hammer set achieved 17800 Metric Tonne of crushing. The sinter plant team won the innovative solution award from Ernst & Young auditors in that year.
2. Supplied Breaker Discs replaced import substitute OEM product. The useful life of Breaker Discs was 5 years. 5 times more than the existing product. ACMECAST lately supplied another set of LBF Midrex DRI spare set to the plant after 5 years as repeat ordered supply.
   ACMECAST has submitted offer for Hot Sinter Breaker Discs for MBF at companies another Steel Plant (India’s Largest Private Sector Steel Plant) at Vijayanagar Bellary in heat resistant alloy OEM specified ASTM A 297 Grade HP alloy for handling high temperature sinter at 700-850°C.
3. Sinter Plant Roll Crusher Horn teeth were not ocured owing to company takeover acquisition that year. Following which the company was acquired by Indian company and did not go through the high capital purchase cost owing to budgeting constrain and resorted to using old solution. However, ACMECAST was approached by the same problem faced by USS Steel Corporation, now Arcelor Mittal Company at One of the Worlds Largest Plate Mill in the USA. The case study report for the same equipment used at its plant was submitted and approved by its Global R&D Centre for trail in the US plant for the recommended solution.
4. The supplied Blast Furnace Burden Roll Over wear plates outperformed OEM. They lasted more than 16 months without asking any maintenance repair. In shut down taken by the maintenance team, some in-situ weld repairs were performed which further extended the life of wear plates by 8 months. Overall useful life of supplied high temperature wear-abrasion resistant composite wear plate were 2.8 times more than previous product used at the plant.
5. Based on above performance of supplied steel plant spares, ACMECAST became a preferred Vendor at its three major integrated steel plants in India.