Papers by Keyword: Ring

Abstract: Ring parts of duplicate gear, double-side flange, high pressure value body, are widely used in engineering machinery, have the common geometrical characteristic of thick-wall, small-hole and deep-groove on the surface. High energy consumption, low material utilization, low productivity and poor quality exist in the current forging technology of this type of rings. In this paper, a new forming method for this type of rings named combined ring rolling (CRR) is proposed. The forming principle of CRR is introduced at first, then, a 3-D coupled thermo-mechanical FE model for the CRR process of a double-side flange ring is developed. By simulation and analysis, the feasibility of CRR technology is testified, and the evolution and distribution rules of stain, temperature, force and power in the rolling process are revealed. The results provide the guideline for the research and development of CRR technology.

Abstract: Bell comes from the Bell of Jiangxi Normal University 70 Anniversary celebration. Ring is the class ring on the campus of Jiangxi Normal University. Soundscape is used to describe the acoustic environment to the listener as the center of, referring to the sound in a certain area of the overall situation. The present study subjectively evaluated the two elements of voice on the campus. We could acquire acoustic waveform and frequency by the physical analysis of both two elements. Bell acoustic showed weakened by the strong cycle, frequency 249.79Hz (B3 +19); ring acoustic frequency was 500.08Hz (B4 +21). Therefore, Bell structured but ring was on the contrary, bell frequency was lower than ring, and bell pitch was slightly lower than ring pitch. Synthesizing physical analysis, subjective evaluation of sound quality, subjective feelings of the two elements (bell and ring), the subjective evaluation of bell was better.

Abstract: A device of petroleum asphalt’s characteristics measuring system was designed in this study. The differential auto-calibration voltage-frequency conversion technology with multi-benchmark resources was applied to measure the temperature. Time-triggered scheduling method was introduced into software design. The intelligent PID algorithm was used for controlling the change rate of temperature. These experiment results showed that the device had high measuring accuracy, and reliability and stability.

Abstract: The vibrational power flow in a submerged infinite cylindrical shell with internal rings and bulkheads are studied analytically. The harmonic motion of the shell and the pressure field in the fluid is described by Flügge shell theory and Helmholtz equation, respectively. The coupling condition on the outer surface of the shell wall is introduced to obtain the vibrational equation of this coupled system. Both four kinds of forces (moments) between rings and shell and between bulkheads and shell are considered. The solution is obtained in series form by expanding the system responses in terms of the space harmonics of the spacing of both ring stiffeners and bulkheads. The vibrational power flow and radiated sound power are obtained and the influences of various complicating effects such as the ring, bulkhead and fluid loading on the results are analyzed. The analytic model is close to engineering practice, which will be valuable to the application on noise and vibration control of submarines and underwater pipes.

Abstract: A spread equation of erbium-doped optical fiber laser was derived from the basic theory of laser. Then, the hypothesis of erbium-doped optical fiber ring laser was proposed. The special computation procedure and the theoretical arithmetic emulation of output characteristic for this laser were conducted by discussing the effect of the configuration. Moreover, this article further investigated the influence of the relationship between pumping and laser output, cavity distribution of gas gain, slope efficiency and the influence that the output coupling rate parameters having on the laser output of optical fiber laser.

Abstract: One-dimensional symmetrical explosive loadings are applied to expand structural components: tubular cylinders, spherical shells and rings of 304 stainless steel and double and single walled cylinders of an aluminum alloy, A5052 to fragmentation, and the effects of wall thicknesses, explosive driver diameters and the constant proportionality of the in-plane biaxial stretching rates are investigated on the deformation and fracture behavior of three types of single walled structures and shatterproof behavior for double walled cylinders experimentally and numerically. In the cylinder tests, the driver is a column of high explosive PETN, inserted coaxially into the bore of a cylinder and initiated by exploding a fine wire bundle at the column axis using a discharge current. In case of the ring tests, ring specimens are placed onto a cylinder charged with the PETN as an expansion driver, and for sphere tests, a specimen filled with the PETN is also initiated by exploding a fine copper wire line with small length located at the central point. Observation results of deformation have shown the final maximum in-plane stretching rate order of , and fracture evaluations on recovered fragments are discussed indicating the need of modified fragmentation model for the structural components. In the double walled cylinder tests, only for lowermost amount of the explosive the outer cylinder has almost caught the fragments of inner cylinder, revealing that the damage phenomena are much different from those for single walled ones.

Abstract: Finite element model was established for the special-section ring rolling. The whole process of ring rolling was simulated based on the DEFORM software. The law that the rolling force is influenced by the idle roll feed speed and main roll rotational speed were found. The results show that the roughcast structure should be similar to finished product structure. IT is significant to optimize roughcast structure and processing parameter, and to improve efficiency of rolling.

Abstract: Explosive loading techniques are applied to expand tubular cylinders, spherical shells and rings of 304 stainless steel to fragmentation, and the effects of wall thicknesses, explosive driver diameters and the constant proportionality of the in-plane biaxial stretching rates are investigated on the deformation and fracture behavior of three basic structures experimentally and numerically. In the cylinder tests, the driver is a column of high explosive PETN, inserted coaxially into the bore of a cylinder and initiated by exploding a fine wire bundle at the column axis using a discharge current from a high-voltage capacitor bank. In case of the ring tests, ring specimens are placed onto a single cylinder filled with the PETN as a expansion driver, and for sphere tests, specimens filled with the PETN are also initiated by exploding a fine copper wire line with small length located at the central point. Two types of experiments are conducted for every specimen and test condition. The first type uses high speed cameras to observe the deformation and crack generation of expanding specimens showing the final maximum in-plane stretching rate of above , and the second uses soft capturing system recovering typically most fragments successfully. The fragments are measured and investigated using a fragmentation model. The effects of test parameters on the deformation and fracture behavior for three types of structures are discussed in need of modified fragmentation model for shell structural elements.

Abstract: This paper presents the study of nested rings crushed laterally between rigid platens at 2 different velocities. In this investigation two different types of nested ring configurations are analysed: (A) In-Plane; where three rings of varying diameter are placed within each other and their axes are parallel. (B) Out of-Plane; where the rings have a 90 degree orientation. Material used was cold finished, drawn over mandrel (DIN 2393 ST 37-2) and is referred throughout the paper as mild steel. The Cowper-Symonds relation was used to predict the dynamic yield stress of the rings and this was included in the FE material model. The results obtained from experiments were compared to that of finite element method using the software package Ansys. Discussion is made on the post – collapse behaviour of these systems. It was found that the Out of-Plane ring system exhibited a more desirable force-deflection response due to its 90 degree orientation.

Abstract: A novel spray deposition technology with characteristic of the movable crucible, has been developed to prepare aluminum alloy and aluminum alloy matrix composite rings with large dimensions. The influences of process parameters on the microstructure and properties of the as-deposited rings were systematically investigated and the process parameters were optimized. Up to now, 7075Al/SiCp and A356/SiCp composite rings with the outer diameter of 1200mm, the inner diameter of 600mm and the thickness of 250mm, and LF6 aluminum alloy ring with the outer diameter of 3500mm, the inner diameter of 3100mm and the thickness of 250mm have been produced respectively. All the as-deposited performs were featured with the grain size about 3~5µm and a homogeneous distribution of ceramic particles the cooling rate up to 104K/s. Moreover, no cracking occurred in the performs because of the lower inner stress. The experimental results indicated that this novel technology was a promising and viable mean for the preparation of metal rings.