Shear Plane Theories of Hot and Cold Flat Rolling

1964 ◽  
Vol 6 (3) ◽  
pp. 219-235 ◽  
Author(s):  
J. W. Green ◽  
L. G. M. Sparling ◽  
J. F. Wallace
Keyword(s):  
Cold Rolling ◽  
Metal Surface ◽  
Hot Rolling ◽  
Upper Bound ◽  
Coulomb Friction ◽  
Shear Plane ◽  
Experimental Results ◽  
Flat Rolling ◽  
Work Done ◽  
Shear Planes

The shear plane theory of hot rolling of thick stock, due to Green and Wallace, is extended to hot and cold flat rolling. Values calculated from the hot rolling theory compared satisfactorily with the theory of Sims and the experimental results of Wallquist. The cold rolling theory is similarly satisfactory in comparison with the experimental results of Ford and it is anticipated that the theory will be more accurate than that of Bland and Ford for small R/h ratios and large reductions. Examples of calculation of load and torque for rolling are given in Appendixes for both Coulomb friction and sticking and shearing at the metal surface and it is shown that both conditions may occur and be taken into account concurrently. A method of determining the total torque is given which is derived from an upper bound to the work done on shear planes which are shown to have the same configuration as that chosen in the analysis of forces.

On the Relative Validity of Two Current Cold-Rolling Theories

1967 ◽  
Vol 89 (1) ◽  
pp. 69-75
Author(s):  
Iain Le May ◽  
K. D. Nair
Keyword(s):  
Cold Rolling ◽  
Yield Stress ◽  
Deformation Rate ◽  
Shear Plane ◽  
Experimental Results ◽  
Relative Validity ◽  
Usual Assumption ◽  
Plane Theory

The paper compares the established cold-rolling theory of Ford, et al., with the more recent shear-plane theory. Recent experimental results obtained by the authors are used in the comparison and it is shown that, although the shear-plane theory is inherently more correct as it does not assume homogeneous compression of the strip, the effect of the usual assumption of a yield stress independent of deformation rate virtually negates any advantage in its use at present.

Rolling of Aluminum

2019 ◽  
Author(s):  
Kai F. Karhausen ◽  
Antti S. Korhonen
Keyword(s):  
Aluminum Alloys ◽  
Cold Rolling ◽  
Hot Rolling ◽  
Heat Exchangers ◽  
Thin Foil ◽  
Aluminum Sheet ◽  
Lightweight Construction ◽  
Sheet Rolling ◽  
Air Conditioners

Because of its lightweight and strength, aluminum alloys are used are being used increasing for the production of lightweight construction. In addition to applications in the expanding transportation market, aluminum sheet and foil materials are traditionally used for food and medical packaging, thin foil, and fin stock for air conditioners and heat exchangers, decorative panels and lithographic sheet. Rolling is a process used for the production of strip or sheet. In this article, rolling processing of aluminum and aluminum alloys is discussed in detail and specific processes include: hot-rolling, cold-rolling, and rolling of aluminum foils.

scholarly journals Study On Setting Method of Flatness Target Curve of SUNDWIG 20-High Mill Considering Target Crown

2021 ◽  
Author(s):  
Jianliang Sun ◽  
Mingze Yan ◽  
Mingyuan Li ◽  
Tongtong Hao
Keyword(s):  
Control Theory ◽  
Cold Rolling ◽  
Hot Rolling ◽  
New Method ◽  
Discrimination Model ◽  
Flatness Control ◽  
Simulation Results ◽  
The Stability ◽  
And Control

Abstract The flatness target curve is important in the flatness control theory. The accuracy of flatness target curve is an important factor to determine the load of flatness control means and flatness quality. Aiming at the defect that crown of each pass after rolling cannot be controlled quantitatively in the traditional target curve formulation of cold rolling, a new method considering the target crown was proposed. Specifically, the target crown of each pass can be set by combining the total proportional crown change in hot rolling field to each pass and the instability discrimination model in cold rolling field. the total proportional crown change of incoming material and finished product is allocated to each pass, and the instability discrimination model is applied to ensure the stability of the plate. The purpose of new method is to control of the crown of each pass quantitatively, so that the flatness and thickness of plate can meet the production requirements. Taking SUNDWIG 20-high mill and typical rolling products as an example, the simulation results show that, on the basis of ensuring the flatness and obtaining the minimum available crown after rolling, the model can make the flatness and crown meet the production requirements at the same time and control the crown of each pass after rolling quantitatively by setting the target crown of each pass.

Calculation of Punch Force and Maximum Pressure for Tube Extrusion

2000 ◽  
Author(s):  
S.-H. Zhang ◽  
Y.-L. Shang
Keyword(s):  
Upper Bound ◽  
Physical Modeling ◽  
Steel Tube ◽  
Experimental Results ◽  
Maximum Pressure ◽  
Punch Force ◽  
Tube Extrusion ◽  
Tooling System ◽  
Very High ◽  
Good Agreement

Abstract Punch force and maximum pressure for tube extrusion can be predicted with an upper bound theory-based program POLSK. Experiments of steel tube extrusion and wax physical modeling were performed. The punch force and the maximum pressure values were obtained. Comparisons were made among the experimental results, physical modeling results and upper bound predictions. It was found that a medium extrusion coefficient causes the lowest pressure on the tooling system, very low and very high extrusion coefficients can both cause very high pressure. It is proved that the upper bound predictions are in good agreement with the experimental results and the upper bound program is suitable for use of steel tube extrusion design.

scholarly journals The Role of Debris-Rich Ice in Flow Near the Margins of Glaciers (Abstract)

1986 ◽  
Vol 8 ◽  
pp. 201 ◽  
Author(s):  
R.W. Baker
Keyword(s):  
Shear Plane ◽  
Conveyor Belt ◽  
Physical Geography ◽  
Supporting Evidence ◽  
Ice Caps ◽  
Considerable Controversy ◽  
Flow And Sediment Transport ◽  
The Subject ◽  
Shear Planes

The margins of many ice sheets and ice caps are marked by the presence of alternating layers of debris-laden and clean ice. The role of this ice in flow and sediment transport near the margins of glaciers has been the subject of considerable controversy between glacial geologists and glaciologists for over three decades. Glacial geologists (Goldthwait, 1951, 1960, 1971, 1975; Bishop, 1957; Souchez, 1967, Boulton, 1970, 1972; Hambrey, 1976) commonly refer to the debris-bearing ice bands as “thrust planes” or “shear planes”, apparently seeing them as reverse faults which transport rock debris from the glacier bed to the surface in a “conveyor-belt-like” manner (Goldthwait, 1975, p. 192). As supporting evidence for the shear-plane mechanism, glacial geologists have offered only qualitative observations and none seem to have actually observed it in action. Glaciologists on the other hand, particularly Weertman (1961), Hooke (1968; 1973), and Hooke and Hudleston (1978), have objected to this concept on physical grounds and have presented convincing arguments for doubting that it is mechanically sound. In spite of the controversy surrounding it, the shear-plane mechanism has gained wide acceptance among geologists and physical geographers and has been perpetuated in recent years through a number of popular introductory geology and physical geography textbooks (e.g. Embleton and King, 1975; Judson, Deffeyes, and Hargraves, 1976; Leet, Judson, and Kauffman, 1978; Press and Siever, 1982; Hamblin; 1982).

Microstructural Study of Newly Designed Ti-6Al-1Fe Alloy through Deformation

2017 ◽  
Vol 264 ◽  
pp. 54-57
Author(s):  
Ayad Omran Abdalla ◽  
Astuty Amrin ◽  
Roslina Mohammad ◽  
M.A. Azmah Hanim
Keyword(s):  
Titanium Alloy ◽  
Cold Rolling ◽  
Hot Rolling ◽  
Lamellar Microstructure ◽  
Ti Alloy ◽  
Beta Transus ◽  
Complete Replacement ◽  
Microstructural Study ◽  
Equiaxed Microstructure ◽  
Transus Temperature

Recently, iron (Fe) is introduced to substitute vanadium (V) in Ti-alloy. Therefore, new (α+β) titanium alloy, Ti-6Al-1Fe was designed through a complete replacement of V by Fe with major composition modifications of Ti-6Al-4V. This new alloy is believed could provide similar properties of Ti-6Al-4V through modification of its microstructures. Different heat treatments can lead to a diversity of microstructural permutations and combinations. Thus, it is very crucial to study in-depth understanding about the microstructure of Ti-6Al-1Fe. Results reveal that the microstructure of as-received alloy is a typical fine lamellar microstructure. The bi-modal microstructure can be obtained by hot rolling below beta-transus temperature (Tβ) followed by recrystallization treatment at 925°C. While cold rolling followed by recrystallization treatment at 925°C produce equiaxed microstructure.

scholarly journals Thermal Behavior of a Rod during Hot Shape Rolling and Its Comparison with a Plate during Flat Rolling

Processes ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 327
Author(s):  
Joong-Ki Hwang
Keyword(s):  
Numerical Simulation ◽  
Thermal Behavior ◽  
Effective Stress ◽  
Hot Rolling ◽  
Rolling Process ◽  
Measured Temperature ◽  
Temperature Deviation ◽  
Shape Rolling ◽  
Hot Rolling Process ◽  
Flat Rolling

The thermal behavior of a rod during the hot shape rolling process was investigated using the off-line hot rolling simulator and numerical simulation. Additionally, it was compared with a plate during the flat rolling process to understand the thermal behavior of the rod during the hot rolling process in more detail. The temperature of the rod and plate during the hot rolling process was measured at several points with thermocouples using the rolling simulator, and then the measured temperature of each region of a workpiece was analyzed with numerical simulation. During hot rolling process, the temperature distribution of the rod was very different from the plate. The temperature deviation of the rod with area was much higher than that of the plate. The variation in effective stress of the rod along the circumferential direction can induce the temperature difference with area of the rod, whereas the plate had a relatively lower temperature deviation with area due to the uniform effective stress on the surface area. The heat generation by plastic deformation during the forming process also increased the temperature deviation of the rod with area, whereas strain distribution of the plate during flat rolling contributed to the uniformity of temperature of the plate with area. The higher temperature deviation of the rod along the circumferential and radial directions during the shape rolling process can increase the possibility of occurrence in surface defects compared to the plate during flat rolling.

Ultrasonic Inspection of Bridge Hanger Pins

2000 ◽  
Vol 1697 (1) ◽  
pp. 19-23 ◽  
Author(s):  
B. A. Graybeal ◽  
R. A. Walther ◽  
G. A. Washer
Keyword(s):  
Nondestructive Evaluation ◽  
Cross Section ◽  
Ultrasonic Inspection ◽  
Shear Plane ◽  
Transverse Cracks ◽  
Bridge Structures ◽  
Reliable Methods ◽  
Shear Planes

Ultrasonic inspection is currently one of the most common and reliable methods used in the inspection of hanger pins in pin-and-hanger bridge structures. Recently, a pin-and-hanger connection on a heavily traveled truck route in the Midwest showed visual indications of being deficient. Field contact ultrasonic inspections were performed on the remaining pin connections. The field inspections indicated that a number of the pins contained cracks or significant wear grooves at the pin shear planes, or both. These pins were replaced and sent to the FHWA’s Nondestructive Evaluation Validation Center for further testing in an ultrasonic immersion tank. The results of the contact and immersion tank ultrasonic studies were nearly identical. Both methods found two pins that contained transverse cracks at the level of a shear plane, with one of these cracks encompassing a majority of the pin cross section. Clearly, for the conditions found in the study, field contact ultrasonics can accurately locate defects in hanger pins.

scholarly journals Surface Plasmon Singularities

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Gabriel Martínez-Niconoff ◽  
P. Martinez-Vara ◽  
G. Diaz-Gonzalez ◽  
J. Silva-Barranco ◽  
A. Carbajal-Domínguez
Keyword(s):  
Shock Wave ◽  
Boundary Condition ◽  
Electromagnetic Field ◽  
Metal Surface ◽  
Surface Plasmon ◽  
Computer Simulations ◽  
Free Space ◽  
Experimental Results ◽  
Physical Features

With the purpose to compare the physical features of the electromagnetic field, we describe the synthesis of optical singularities propagating in the free space and on a metal surface. In both cases the electromagnetic field has a slit-shaped curve as a boundary condition, and the singularities correspond to a shock wave that is a consequence of the curvature of the slit curve. As prototypes, we generate singularities that correspond to fold and cusped regions. We show that singularities in free space may generate bifurcation effects while plasmon fields do not generate these kinds of effects. Experimental results for free-space propagation are presented and for surface plasmon fields, computer simulations are shown.

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