Advanced Materials Research Vol. 983

Abstract: The shock spectrum of gearbox was gotten according to German specification. And the equivalent time-domain acceleration curve was converted from shock spectrum. After the dynamic finite element model of entire gearbox was established by using the truss element, spring element and tetrahedral element, the shock response including the vibration velocity, acceleration and dynamic stress of gearbox subjected to the acceleration shock excitation were simulated. At last, the anti-shock performance of gearbox was analyzed combining with the strength criterion.

Abstract: Stud welding plays an important role in fixing stud on car bodies. The quality of stud welding is seriously affect automotive security. During the stud welding process,stud welding machine by monitor welding current,welding voltage and welding time to determine the welding quality is good or bad,and uses the average parameter monitoring system,but there are many defects of welding quality relate to these instantaneous value of the parameter.Based on the above issues, designed a dynamic parameter detection system.through the real-time monitoring of dynamic parameter,it can more accurately detect the defects of welding quality.

Abstract: Using the lateral ,shift and shift time of REFRACTION coefficient of SH seismic wave at the interface of strata, we derived and given formulae of normal move out of lateral shift, discussed the influence of lateral shift on normal move out of SH-wave, and drawn the curves of normal move out of lateral shift and the error of normal move out caused by lateral shift with respect to the angle of incidence. The results show that for glancing wave or angle of incidence being near the critical angle, A large error can be caused by lateral shift; The error correction of lateral shift should be done before seismic data processing.

Abstract: Based on the model of rigid-spring element suitable for homogeneous elastic problem, which was developed by Japanese professor Kawai, the interface stress element model (ISEM) for solving the problem of discontinuous media mechanics has been established. Compared with the traditional finite element method (FEM), the ISEM is more accurate and applicable. But on the other hand, the total number of freedom degree of ISEM in dealing with three-dimensional problems is higher than that of FEM, which often brings about the negative effects on efficiency of calculation. Therefore, it is necessary to establish a mixed model by gathering the advantages of ISEM and FEM together. By making use of the good compatibility of ISEM and introducing the concept of transitional interface element, this paper combines the counting methods of ISEM and FEM, and proposes a mixed model of ISEM-FEM, which can solve, to a large extent, the contradictions between accuracy and efficiency of calculation. The examples prove the applicability and adaptability of this model to engineering.

Abstract: This paper aims at directly modeling the transfer functions of mass-spring-damper systems. Using complex stiffness of mass, spring, and damper elements and equivalent complex stiffness of these elements in series and/or in parallel, the transfer functions of the mass-spring-damper systems are modeled quickly. This is very convenient to the modeling of the complicated mechanical systems.

Abstract: The flow characteristic and differential pressure-flow of outlet blockage fault and trouble-free for control valve are simulated by CFD. The study shows that the vortex at the bottom of control valve outlet is main reason for the outlet blockage fault, relative gain of flow characteristic curve for outlet blockage is increased, the flow percentage of outlet blockage compared with trouble-free is maximum value at relative opening is 60% and 100%, the pressure - flow percentage reaches maximum value at differential pressure is 800 kPa.

Abstract: In auto safety components crash test, noise and interference signals is inevitable in the collected physical data, which will seriously affect the accuracy of the data. In this paper, the advantages and disadvantages are compared between IIR filters and FIR filters, a Butterworth filter is designed using the impulse response invariant method, and a filtering software is developed to meet the need of data processing for different measurement projects. The results showed that: according to different test data, the filter can achieve CFC filtering of different frequency levels, exclude interference data, preserve useful information, which ensures data accuracy and reliability, provides a convenient for the following data processing.

Abstract: This paper analyzes the factors that cause axial fatigue testing machine not coaxiality and influence on test results, put forward the axial fatigue testing machine alignment inspection, and designed a new type concentric structure to adjust not coaxiality.

Abstract: The handling unit based on PLC is composed of seven motors, Programmable Logic Controller, touch panel, sensor and so on, The unit controls the bucket to move up and down, left and right with seven motors, and back and forth and regulates the speed of motor movement with speed regulators, complete the material transport, the touch panel help realize the manual and full-automatic control of motor and the switching between manual and automatic modes. The handling unit based on PLC for strengthening the operating ability in college or junior technical personnel are of great help.

Abstract: The typified as flexible thermosetting pipe, is a new product, developed initially in response to the need for a non-metallic replacement for steel pipe used for oil and gas productions. This product may use for high pressure down-hole applications in which the pipe could repeatedly transported onto a drum. The proposed pipe comprise an internal thermoplastic layer play as liner and a fluid-tight cover, and one or more dual-helical wounding tape stacks applied to the internal liner for absorbing axial and bending loads. The tape stacks are wrapped helically onto the pipe structure with adjacent gaps between wrappings tape to reduce the pressure integrity of the tubular pipe structure. The composite tape stacks are formed from a plurality of thin tape strips and are bonded to each other within a stack. All the layers are manufactured from composite material consisting of highly noncorrosive epoxied matrix reinforced by long continuous fibers. Thus, the proposed flexible pipe designed to be stand alone with thermoplastic liner over-wound with one or more of an epoxy-based structural thermosetting laminate. To this aim, a straightforward simulations of thermosetting pipe is developed via using ANSYS software. Apart from possessing an accurate operational condition, on account of its simplicity the proposed simulation seems also very suitable for further developing and prototyping purposes. Finally, it has been shown that the proposed thermosetting pipe, which partially attains some classical characteristic of both offshore and onshore pipeline by a different line of reasoning, is may serve as a reference in designing flexible pipe.