TPT July 2011

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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
Material X155CrVMo121 D2 SKD11
high chromium
alloy (casting
state, eliminated
stress temper)
high chromium
alloy (quenching,
temper state)
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)