studies on the wear performance of different blade materials

studies on the Wear Performance of different materials of rotary Bladesravinder kaur, i. s. dhaliwal and ajaib singhDepartment of Farm Machinery & Power Engineering

PAU, Ludhiana-141004

aBstractWear of soil engaging components occurs because the materials used are normally softer than the natural abrasives in the soil. Most of blades of Rotavator are manufactured locally which are hardly at par with the standards in terms of material, shape and size which affects operational life of rotary tool. So, there was a need to study wear characteristics of rotary blades so as to provide the suitable blades in the rotary tools. Study was conducted in rotary soil bin in loamy soil and sandy loam soil. L-Shape blade of four different makes was mounted on the two flanges and their speed varied from 140-150 rpm. Two rollers along their stand were mounted on soil bin for compressing the soil upto 4.5 – 5.0 kg/cm2 compaction. After running the blades for 50 h in the soil bin, blades were weighted and loss in weight and dimensional wear loss was noted down. Similar procedure was followed for 100 h and 150 hr time intervals. It was observed that the weight loss of rotary blades was proportional to time. In loamy soil maximum average weight loss was 6.76% in blade T2 low alloy steel (LAS) having 0.280% carbon content and minimum average weight loss was 0.86% that occurred in blade T3 high carbon spring steel (HCSS) having carbon content 0.64% after 150 hours of working period. In sandy loam soil maximum average weight loss was 10.02% that occurred in blade T4 low carbon steel (LCS) having carbon content of 0.250% and minimum average weight loss was 4.09% that occurred in blade T3 high carbon spring steel (HCSS) after 150h of working period. The width of worn out blades decreased with operational hours. In loam soil maximum average loss in width was 13.20% in blade type T2 low alloy steel (LAS) and minimum average width loss was 3.18% in blade type T3 high carbon spring steel (HCSS) after 150h of working period. In sandy loam soil maximum average width loss was 14.68% in blade type T4 low carbon steel (LCS) and minimum average width loss was 8.27% in blade type T3 high carbon spring steel (HCSS) after 150h of working period.

keywords: Rotavator, Soil bin, Low alloy steel, High carbon steel

introductionThe rapid wear of soil engaging machine parts is responsible for most of the idle

time for maintenance, as well as expenditures for repairs and manufacture of spare parts. Increasing the service life of machines has become one of the most important challenges of technological process. The problems of increasing durability are inseparably linked with the study of friction and wear patterns of machine parts in operation.

Gupta and Pandey [1] evaluated straight cutting edge and spiral cutting edge rotary tiller blades in soil bin. Four different rotary speeds with two modes of operation were used to conduct the study. The linear speed 1.33 km/h and the working depth 100mm were kept constant. The study revealed that blade with spiral cutting edge gave about 9.13 percent higher performance index than straight cutting edge blade.

Salokhe et al [2] conducted a study on wear testing of enamel coated M.S relative to those of uncoated M.S rings. This study was conducted to investigate wear

Journal of Research, SKUAST-J, Vol. 10, No. 1, pp 24-32 (2011)

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characteristics relative to those of uncoated mild rings. The tests were conducted in sandy soil and on sand papers of silicon carbide. Results of studies were expressed in terms of weight loss and wear rate in relation to test duration. It was observed that over a period of 120 h of testing in sandy soil, amounts of wear of enamel coated rings and uncoated mild steel rings were almost the same. The tests on sand papers showed that enamel coated rings wore faster than M.S rings. The rate of wear of enamel coated rings, however was not so high to render the process impractical for use in improving the performance of soil engaging devices used in agriculture.

Singh et al [3] conducted a study on wear characteristics of reversible shovels of seed cum fertilizer drill. Wear test on five different samples of shovels i.e., mild steel, spring steel, high carbon steel, coated mild steel and heat treated mild steel were conducted on rotary soil bin for 100 h. Loss in weight for each shovel due to wear was recorded. Three types of soil i.e., light medium and heavy soils were used for tests. Based on comparative analysis, they found that heat treated M.S shovels is best keeping in view the life of shovels as compared to normal M.S shovels.

Zhang and Kushwaha [4] studied wear characteristics of several cultivator sweeps using a newly developed abrasive tester. Comparisons were made between the regular sweep and hardfaced edge sweeps. The hardfaced sweeps proved to have better wear resistance. The wear characteristics were also evaluated by measuring the profile change of the sweeps using the image analysis. The draft of new and worn sweeps was evaluated in conventional soil bin. The results showed a decrease in draft of worn sweeps due to the change in the projected area of sweeps.

The study showed that cutting edge of L–shaped rotavator blade section was most susceptible to wear with increased operational hours. Gravimetric and dimensional wears differ significantly with respect to treatment, working period, width and thickness of blades. Further, most of the blades are manufactured locally which are hardly at par with the standards in terms of material, shape and size which affects operational life of rotary tool. Therefore, there is a need to study wear characteristics of rotary blades so as to provide the suitable blades in the rotary tools.

materials and methodsexperimental set-up

For studying the wear characteristics of rotary blades the study were conducted in Rotary soil bin. (Fig.1)

Two flanges were mounted on the rotary soil bin. The diameter of each flange was 47 cm and the rpm of each flange were kept in the range 140-150 rpm. Two rollers of diameter 33 cm and length 36 cm along with their stands were mounted on the soil bin for compressing the soil upto 4.5-5 kg/cm2. Compaction of soil was adjusted with the help of springs mounted on the rollers.

Wear performance of different materials of rotary blades

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Journal of research, skuast-J

experimental techniqueL-shaped blades of four different makes and materials were used for the

study as shown in Fig. 2. These blades were mounted on the two flanges. The material specifications of the blades are as given in Table 1.

Fig. 1: Experimental set up for the study

Blade type T1 (LCS) Blade type T2 (LAS)

Blade type T3 (HCSS) Blade type T4 (LCS)

fig. 2: Different types of blades used in the soil bin

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Table 1: Material specifications of the blades

Element concentration in percentage by weight (ferrous)

sr. no. c s P si mn cr Blade type Material specification

1 .290 .012 .018 .27 1.49 - T1 LCS (Low carbon steel)2 .280 - - - 1.37 .52 T2 LAS (Low alloy steel)3 .640 .028 .039 .24 1.12 - T3 HCSS (High carbon spring steel)4 .250 .012 .012 .29 1.14 - T4 LCS (Low carbon steel)

Initially soil bin was filled with loam soil. All the twelve blades to be mounted on the two flanges were weighed and then these were mounted on the two flanges. After running the blades for 50h in soil bin, blades were weighed again and loss in weight was noted down. Dimensional wear loss was also noted down. Then similar procedure was followed for 100h and 150h time intervals. After that the soil in soil bin was replaced by sandy loam soil and above said similar procedure was followed to measure the weight loss, dimensional wear loss after 50h, 100h and 150h intervals of time with a new set of 12 blades. The independent and dependent variables used in the study are given in Table 2.

Table 2: Independent and Dependent variables

Sr. No. Independent Parameters dependent Parameters

1. Soil type Weight loss

2. Blade type Dimensional wear

3. Number of working hours

results and discussion

effect on weight loss of rotary blades in loam soilThe weight loss of all four blades after 50h working period has been shown

in Fig. 3. The weight loss of blade T1 was 0.97%, blade T2 was 1.14%, blade T3 was 0.27% and blade T4 was 0.29%. The weight loss of all the four blades after 100h has been represented in Fig. 4. Blade T1, T2, T3 and T4 showed 2.12%, 3.16%, 0.45% and 1.96% weight loss respectively. The comparative performance of four blades after 150h of working period has been represented in Fig.5. It represents that maximum wear 6.76% occurred in blade T2 followed by blade T1 showing 3.82% weight loss, blade T4 having 2.94% weight loss and blade T3 having 0.86% weight loss. Blade T3 made by HCSS gave the best performance in loam soil having least weight loss (0.86%) after 150h of working period.


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Blade T3 showed minimum wear because of high concentration of carbon (0.640%) which was imparting hardness, elasticity and tensile strength to it and made it wear resistant. 1.12% Mn was also imparting strength and hardness to it. Although blade T2 was having good percentage of carbon and manganese even though it showed maximum wear due to 0.52% Cr which was imparting less wear resistant characteristics counteracting hardenability to abrasion and wear which it gave on joining with carbon in loam soil. Wear in blade T1 was lesser than wear in blade T2 due to the reason that blade T1 was having more carbon (0.290%) and Mn (1.49%) as compared to blade T2 having 0.280% C and 1.37% Mn. Here, more carbon and manganese content in blade T1 as compared to blade T2 gave it more wear resistant characteristics.

Quality with blade T4 mark gave better performance as compared to blade T1 even though it was having lesser carbon and manganese content than blade T1. It was due to the reason that it was having less phosphorus content in comparison with blade T1 which was making it more impact resistant. Silicon content in blade T4 was more than in blade T1 which was making it tougher in loam soil.

effect on weight loss of rotary blades in sandy loam soil2.85% in blade T3 and 6.02% weight loss occurred in blade T4. The comparative

performance of four blades has been shown in Fig. 8 after 150h of working period. It

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represents that maximum wear 10.02% occurred in blade T4 followed by blade T2 (7.01%), blade T1 (4.5%) and blade T3 (4.09%) weight loss after 150h of working period. It indicates that blade T3 gave best performance having 4.09% weight loss after 150h of working period.

Fig. 9 indicates that blade T3 gave best performance in terms of weight loss after 150h of working period showing 0.86% weight loss in loam soil and 4.09% weight loss in sandy loam soil. Blade T3 mark showed minimum wear because of high concentration of carbon (0.640%) which was imparting hardness, elasticity and tensile strength to it which made it wear resistant. 1.12% Mn also imparted strength and hardness to it. Blade T4 mark was having least carbon content which imparts hardness and tensile strength to it out of the four qualities due to which it was showing maximum wear.

Blade T2 mark showed lesser wear than blade T4 because it was having good concentration of C (0.280%), Mn (1.37%) and Cr (0.52%) . Here manganese content was greater in T2 which was imparting more strength to it as compared to blade T4. Blade T1 mark showed lesser wear than blade T2 due to high concentration of C (0.290%) and Mn (1.49%) than T2 which were imparting hardness, strength and made it wear resistant than T2.

effect on dimensional wear of rotary blades in loam soilThe average dimensional wear loss of all the four blades after 50h of working

period has been represented in Fig. 10. It shows that dimensional wear of 1.53% occurred in blade T1, 1.90% in blade T2, 0.05% in blade T3 and 1.12% in blade T4. The dimensional wear loss that occurred in all the four blades after 100h has been


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represented in Fig. 11. It shows 6%, 7.37%, 1.67% and 2.59% dimensional wear loss occurred in blades T1, T2, T3 and T4 respectively. The comparative performance of four blades after 150h of working period has been shown in Fig. 12. It indicates that maximum average dimensional wear loss 13.20% occurred in blade T2 followed by blade T1(9.89%), blade T4(4.07%) and blade T3(3.18%). It indicates that blade T3 gave best performance showing 3.18% average dimensional wear loss after 150h of working period.

Minimum wear was shown by blade T3 due to high concentration of carbon (0.640%) which was imparting hardness, elasticity and tensile strength to it which made it wear resistant among all the four qualities. 1.12% Mn also imparted strength and hardness to it. Although blade T2 mark was having good percentage of carbon and manganese even though it was showing maximum wear due to 0.52% Cr which imparted less wear resistant characteristics counteracting hardenability to abrasion and wear which it gave on joining with carbon in loam soil. Blade T1 mark was having 0.290% C, 0.012% S, 0.018% P, 0.27% Si, 1.49% Mn. Wear in T1 was lesser than in blade T2 due to the reason that blade T1 was having more carbon (0.290%) and Mn (1.47%) as compared to blade T2 having 0.280% C and 1.37% Mn. Here high concentration of carbon and manganese in blade T1 was imparting strength in comparison with blade T2

Blade T4 mark gave better performance as compared to blade T1 even though it was having lesser carbon and manganese content than blade T1 it is due to low concentration of phosphorus in blade T4 which made it more impact resistant. Silicon content in blade T4 is more than in blade T1 which was making it tougher in loam soil.

effect on dimensional wear of rotary blades in sandy loam soilThe average dimensional wear loss in all the four blades after 50h has been

represented in Fig.13. It shows that blade T1 was having 1.59% average dimensional wear loss, blade T2 had 2.57%, blade T3 showed 1.13% and blade T4 showed 2.71% average dimensional wear loss.

The average dimensional wear loss after 100h for all the four blades has been shown in Fig. 14. It shows that 6.40% average dimensional wear loss occurred in blade T1, 7.58% in blade T2, 4.35% in blade T3 and 8.35% average dimensional wear loss in blade T4.

The comparative performance of four blades after 150h of working period has been shown in Fig. 15. It indicates that maximum average dimensional wear loss 14.68% occurred in blade T4 followed by blade T2 (13.43%), blade T1 (10.12%) and 8.27% in blade T3. It indicates that blade T3 gave best performance showing 8.27% average dimensional wear loss after 150h of working period.

Fig. 16 indicates that in terms of average dimensional wear loss, blade T3 gave best performance in loam soil showing 3.18% wear loss and 8.27% wear loss in sandy

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loam soil. Blade T3 mark suffered minimum wear due to high concentration of carbon (0.640%) which imparted hardness, elasticity and tensile strength to it due to which it became wear resistant. Strength and hardness was imparted to it due to 1.12% Mn. Blade T4 mark was having least carbon content i.e. 0.250% out of the four qualities due to which it showed maximum wear. Here, silicon may be forming iron sulphide which makes it less. If there had been formed manganese sulphide there would not have been any undesirable effect. Blade T2 mark showed lesser wear than blade

T4 due to the reason that it is having more carbon and manganese content which imparts hardness to it in comparison with blade T4. Blade T1 mark showed lesser wear than blade T2 due to high concentration of C (0.290%) and Mn (1.49%) which were imparting hardness, strength and made it wear resistant in comparison with blade T2.

Thus, it is concluded that the weight loss of rotary blades was proportional to time. The rate of wear varied with soil type. Wear in sandy loam soil was more than in loam soil. In loam soil, minimum average weight loss was 0.86% which occurred in blade T3 and maximum average weight loss was 6.76% which occurred in blade T2 after 150h of working period. In sandy loam soil, minimum average weight loss was 4.09% that occurred in blade T3 and maximum average weight loss was 10.02% and that occurred in blade T4 after 150h of working period. The wear in width differed significantly with the quality of the blade. The width of worn out blades decreased with operational hours. In loam soil, minimum average width loss was 3.18% that occurred in blade T3 and maximum average loss in width was 13.20%, that occurred in blade T2 after 150h of working period.

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In sandy loam soil, minimum average width loss was 8.27% that occurred in blade T3 and maximum average width loss was 14.68% that occurred in blade T4 after 150h of working period. In sandy loam soil minimum average width loss was 13.08% that occurred in quality mark T3 and maximum average width loss was 18.32% that occurred in quality mark T4 after 200h of working period.

references1. Gupta, J. P. and Pandey, K. P. 1991. Performance of spiral and straight edge tines of

rotary tillers under wet land condition. J. Japanese Society of Agricultural Machinery 60 : 11-18.

2. Salokhe, V. M., Gee. Clough. D. and Tamtomo, P. 1991. Wear testing of enamel coated rings. J. Soil Tillage Res. 21: 121-31.

3. Singh, Joginder., Singh, Irvinder. and Shukla, L. N. 1993. Wear characteristics of reversible shovels of seed cum fertilizer drill. J. AMA 24: 13-15.

4. Zhang, J. and Kushawa, R. L. 1995. Wear and draft of cultivator sweeps with hardened edges. J. Canadian Agril Engng 37: 41-47.

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studies on the wear performance of different blade materials

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