TPT July 2011

A rticle

3.2.2 Compared with mechanics property See table 1 3.3 Compared with wear resistance property 3.3.1 Contrast of wear resistance at field: same equipment and rolling same steel pipe The contrast of wear resistance for hot straightening on the straightening mill – see table 2. The contrast of wear resistance of cold straightening on the straightening mill of Ø250 MPM mills – see table 3. 3.3.2 Compared with wear resistance property test in laboratory This test introduced the MM-200 ring-block type friction and wear-

testing machine. The test cooling with water is achieved using a self- made system. The main testing parameter is as follows: Loading power: 57N, rotating speed of principal axis: 100 r/min, testing time: 30 min/piece, cooling water speed: 30 dripping/min, material of friction ring: YG8, size of friction ring: Ø50mm Material of friction block: Blocks are separately made from above mentioned five kinds of materials. Every material has three pieces. Size of friction block: 11×11×4.5mm

No.

A

B C

D

E

high chromium alloy (casting state, eliminated stress temper)

high chromium alloy (quenching, temper state)

Material X155CrVMo121 D2 SKD11

Figure 5: No A. testing figure and testing value of hardness of X155CrVMo121 steel pipe straightening roll sample

Figure 6: No. B testing figure and testing value of hardness of D2 steel pipe straightening roll sample

Figure 7: No. C testing figure and testing value of hardness of SKD11 welding pipe roll sample

Figure 8: No. D testing figure and testing value of hardness of high chromium alloy pipe

straightening roll sample (casting state, eliminated stress temper)

Figure 9: No. E testing figure and testing value of hardness of high chromium alloy welding pipe roll sample (quenching, temper state)

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J uly 2011

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