Exploration of Geotechnical Engineering Investigation under Complex Topographical and Geological Conditions

This paper will explore the geotechnical engineering investigation technology under the complex topographical and geological conditions, and introduce how to construct the water supply tube wells faster and better under the complex topographical and geological conditions by taking Inner Mongolia as an example, so as to provide reference for the relevant professionals

Complex Processing of Industrial Products and Lead-Copper Concentrates

This article describes the modern technologies of processing of industrial products and copper-lead waste products, and their physical and chemical properties as well as laboratory tests for processing slurries and zinc slags. Experiments have shown that the temperature of the melt in the reduction of lead-containing slag should be within 1100–1200 °C. The key criteria for separating melting products to different phases are the difference in density, viscosity and surface tension of the melted slag. The separation of the molten slag to the phases and the reduction of the settling time of the melt in the furnace will be promoted by the increasing the density and surface tension of the lead and matte-molten slag, and reduction in viscosity of the latter. The processing of lead-copper-zinc containing sulfide raw material was carried by the reduction smelting method and the purging of melt with a natural gas at a rectangular electric furnace. Dust collection system was connected to the furnace through the duct work. The feedstock loading was carried out through the furnace crown. The purging of melt with natural gas was performed after the melting of the charge using the immersed gas supply tube. The gaseous products were derived from the melting furnace through the flue. The gas supply tube was fitted with a gear system to adjust the depth of the tube immersion. As results of experiments were obtained sharply separable intermediates with a high degree of concentration: lead into lead bullion to 92–94%; copper into matte to 90–91%; zinc to the slag and sublimates to 94–96%. Thus the material costs for processing of copper matte and zinc slag will be reduced and the yield of sublimates consisting primarily of vapor and metallic zinc sulfide will be decreased.

Development of a Linear-Motor-Driven Table Supported by Hydrostatic Water Bearings: Effect of Air Volume Contained in Water-Supply Tube on Pitching Motion of Table Slider

A linear-motor-driven table supported by hydrostatic-water bearings had been developed. The table slider is supported by a single-sided recess type bearing system and preloaded by attractive force using a linear-motor magnet. Since eccentric excitation force is applied to the table slider due to the change of attractive force according to the magnet track position of the linear-motor, pitching motion of the table occurs. This paper investigates the effect of air volume contained in a water-supply tube on the pitching motion. Larger air volume results in lower natural pitching frequency of the table slider, lower logarithmic decrement of the pitching motion and larger pitching angle. When the natural pitching frequency corresponds to the frequency of the eccentric excitation force during table feed, pitching angle grows by resonation.

A Case Study on Generation of Acceptance Criteria in Feedwater Supply Tube Bends

Inspection of components utilizing advanced examination techniques is becoming standard practice in the power industry. One of the critical aspects during this type of inspection is to have on hand criteria for acceptance or rejection of flaws found during these inspections. The examinations typically include the use of advanced ultrasonic techniques such as Linear Phased Array (LPA), Focused Annular Phased Array (APA), and Time of Flight Diffraction. These techniques can detect and size flaws that are often “Fit for Service” for at least one additional outage cycle. However, schedule limitations during an outage often do not permit for extensive analysis time. Repair decisions need to be made immediately and having criteria available for these decisions are critical. The following is a case study for the generation of acceptance / rejection criteria for power boiler feedwater supply tube bends. The determination of “allowable flaw sizes” is needed to determine which of these supply tube bends need to be removed during the outage. The acceptance criteria in this work is based on the criteria of API 579-1 / ASME FFS-1 “Fitness for Service Standard” [1] to evaluate the rate of growth of the flaws found. Discussion is also made as to the sensitivity of the examination methods used to detect the flaws expected and how this relates to the acceptance criteria generated.

Failure Analysis of the Steam Injected Aeroderivative Gas Generator During Acceptance Running

This paper discusses the extensive failure of a widely used aeroderivative gas generator during certification running. The steam-injected engine had 1241 hours of logged operation in a regeneration facility providing process steam to the gas plants and electric power to the grid. The engine operating parameters and metallurgy of the damaged hardware’s components are reviewed. External and internal evidences displayed serious damage of the compressor rear frame assembly caused by an internal fire. The major damage was in the axial direction from aft of the compressor rotating CDP (compressor discharge pressure) seal and ended at the stage one high pressure turbine nozzle support. The internal fire was caused by lube oil leaking through a worm-hole in the oil supply tube connector located at the CRF (compressor rear frame). The hole was made by rubbing of the oil supply tube with the edges of the insulation blanket. The air at this location carries sufficient thermal energy at high power settings to create auto-ignition condition. The failure was an isolated event in the well-reputed history of the engine.