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The effects of forming parameters on conical ring rolling process.

Meng W, Zhao G, Guan Y - ScientificWorldJournal (2014)

Bottom Line: The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied.The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the "obtuse angle zone" of ring's cross-section are higher than those at "acute angle zone"; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces.Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China.

ABSTRACT
The plastic penetration condition and biting-in condition of a radial conical ring rolling process with a closed die structure on the top and bottom of driven roll, simplified as RCRRCDS, were established. The reasonable value range of mandrel feed rate in rolling process was deduced. A coupled thermomechanical 3D FE model of RCRRCDS process was established. The changing laws of equivalent plastic strain (PEEQ) and temperature distributions with rolling time were investigated. The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied. The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the "obtuse angle zone" of ring's cross-section are higher than those at "acute angle zone"; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces. As the ring's outer radius growth rate increases at its reasonable value ranges, the uniformities of PEEQ and temperature distributions increase. Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained.

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Related in: MedlinePlus

The schematic diagram of RCRRCDS process at t time.
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fig1: The schematic diagram of RCRRCDS process at t time.

Mentions: Figure 1 shows the schematic diagram of RCRRCDS process at t time. In Figure 1, RD is the bottom-radius of driven roll; RM is the bottom-radius of mandrel; Rt is the ring's bottom outer radius at t time; rt is the ring's bottom inner radius at t time; bt is the thickness of ring wall at t time; H is the height of conical ring; θ is the included angle between ring wall and X axis; RD′ is the driven roll's radius at l layer-height; RM′ is mandrel's radius at l layer-height; Rt′ is the ring's outer-radius at l layer-height and at t time; rt′ is the ring's inner-radius at l layer-height and at t time; t is the rolling time; l is the layer-height of conical ring. The value ranges of l, t, and H are (0 ≤ l ≤ H),  (0 ≤ t ≤ Ttotal), and (0 < H ≤ RMtanθ), respectively. Ttotal is the total rolling time.


The effects of forming parameters on conical ring rolling process.

Meng W, Zhao G, Guan Y - ScientificWorldJournal (2014)

The schematic diagram of RCRRCDS process at t time.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4150487&req=5

fig1: The schematic diagram of RCRRCDS process at t time.
Mentions: Figure 1 shows the schematic diagram of RCRRCDS process at t time. In Figure 1, RD is the bottom-radius of driven roll; RM is the bottom-radius of mandrel; Rt is the ring's bottom outer radius at t time; rt is the ring's bottom inner radius at t time; bt is the thickness of ring wall at t time; H is the height of conical ring; θ is the included angle between ring wall and X axis; RD′ is the driven roll's radius at l layer-height; RM′ is mandrel's radius at l layer-height; Rt′ is the ring's outer-radius at l layer-height and at t time; rt′ is the ring's inner-radius at l layer-height and at t time; t is the rolling time; l is the layer-height of conical ring. The value ranges of l, t, and H are (0 ≤ l ≤ H),  (0 ≤ t ≤ Ttotal), and (0 < H ≤ RMtanθ), respectively. Ttotal is the total rolling time.

Bottom Line: The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied.The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the "obtuse angle zone" of ring's cross-section are higher than those at "acute angle zone"; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces.Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan, Shandong 250061, China.

ABSTRACT
The plastic penetration condition and biting-in condition of a radial conical ring rolling process with a closed die structure on the top and bottom of driven roll, simplified as RCRRCDS, were established. The reasonable value range of mandrel feed rate in rolling process was deduced. A coupled thermomechanical 3D FE model of RCRRCDS process was established. The changing laws of equivalent plastic strain (PEEQ) and temperature distributions with rolling time were investigated. The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied. The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the "obtuse angle zone" of ring's cross-section are higher than those at "acute angle zone"; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces. As the ring's outer radius growth rate increases at its reasonable value ranges, the uniformities of PEEQ and temperature distributions increase. Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained.

Show MeSH
Related in: MedlinePlus