Influence of Plasma Heating on the Metallurgical Effects of a Continuous Casting Tundish

Steel products have experienced long-standing problems such as unstable product quality and low product homogeneity. In the continuous casting process, realizing constant-temperature pouring is an effective way to improve product homogeneity. Plasma heating can compensate for the temperature drop during casting with a tundish and maintain a stable degree of superheating of the molten steel in the tundish. Plasma heating has a certain impact on the cleanliness of the molten steel and on the tundish covering flux in the tundish while compensating for the temperature drop. This paper uses SEM-EDS, XRD and FactSage to analyze the cleanliness of molten steel and the characteristics of the tundish covering flux before and after plasma heating. The results show that the number density of inclusions in the tundish is significantly lower after heating, improving the floating removal of small-sized inclusions; after heating, the surface morphology of the tundish covering flux sample appears transparent and glassy, with uniform morphology. XRD results show that the tundish covering flux after plasma heating exhibits no crystal precipitation and is amorphous and that there is a certain regularity before and after heating; there are no obvious changes in the composition of the tundish covering flux in the liquid phase area.

Influence of Plasma Heating on the Metallurgical Effects of a Continuous Casting Tundish

Steel products have experienced long-standing problems such as unstable product quality and low product homogeneity. In the continuous casting process, realizing constant temperature pouring is an effective way to improve product homogeneity. Plasma heating can compensate for the temperature drop during casting with a tundish and maintain a stable degree of superheating of the molten steel in the tundish. Plasma heating has a certain impact on the cleanliness of the molten steel and on the tundish covering flux in the tundish while compensating for the temperature drop. This paper uses SEM-EDS, XRD and FactSage to analyze the cleanliness of the molten steel and the characteristics of the tundish covering flux before and after heating. The results show that the number density of inclusions in the tundish is significantly lower after heating, improving the floating removal rate of small-sized inclusions; after heating, the surface morphology of the tundish covering flux sample appears transparent and glassy, with uniform morphology; XRD results show that the tundish covering flux after plasma heating exhibits no crystal precipitation and is amorphous and that there is a certain regularity before and after heating; there are no obvious changes in the composition of the tundish covering flux in the liquid phase area.

An Operations Improvement Plan for Engineering Company

Some engineering companies which design and produce engineering equipment and systems have deficiency of unstable product quality followed by gradually raised costs for after-sales maintenance and repair. The purpose of this report is to help explore and discuss possible issues which may contribute to this deficiency and then to seek solutions for better operations management. Methodologies such as performance control system, material management, quality management and inter-relationships management were learned from, while adopted techniques and tools contain: EOQ, TQM, ISO approach, Six Sigma, ServQual, value-chain ap- proach and PDCA. Based on step-by-step analysis, the report recommends introduction of performance control, material management techniques, RD databases and further standardization, quality management, and inter-relationships methodology.

Appraising waters — The assimilation of chemists into the trade of mineral waters in eighteenth-century France

Mineral waters were a delicate and unstable product whose value as a remedy increased in early modern France. If it was once the prised luxury of the nobility travelling to the spa, the eighteenth century slowly watched it turned into a commodity. The waters became widely available in bottles and were sold in bureaus of distribution. Despite the logistical challenges of selecting and carrying the waters to their new urban public, many different springs made their way into most of France’s cities. This took place under the watch and regulation of a uniquely dedicated institution, the Société de Médecine. This Société eventually settled its authority over the management of mineral waters, thanks to the backing of state power, the influence of the Academy and the newly recognized authority of chemists as analysts of waters. The purpose of this paper is to bring to light this overlooked institution and its essential role in the administration of mineral waters. Though it never eradicated fraud or succeeded in creating a full scientific and economic monopoly, it greatly broadened the budding trade of bottled water in France and gave a powerful incentive for chemists to better their mastering of the particularly challenging analysis of water.

THE IMPORTANCE OF RAW MATERIALS INVENTORY SUPERVISION FOR PRODUCTION PROCESS

This paper describes the importance of the raw materials Inventory supervision for production process. The concepts described in this paper was studied using the descriptive theoretical analysis. It is concluded that (1) Raw Materials Inventory control is highly needed by both small and big companies to take care of the production process stabilization; (2) The production process will find problems when there is no good control of the Inventory. This causes anstable production process effecting finnace of the companies. The long period of materials inventory causes campany loss. On the other hand, small amount of inventory will also cause the production processes stop. Such situation will also influence marketting and the supply to the consumers; (3) Unstable producation process will cause unstable product supply in the market, and (4) To ensure that the consumers’ needs are continuously completed, control of the raw materials inventory needs to be done and maintained.

THE IMPORTANCE OF RAW MATERIALS INVENTORY SUPERVISION FOR PRODUCTION PROCESS

This paper describes the importance of the raw materials Inventory supervision for production process. The concepts described in this paper was studied using the descriptive theoretical analysis. It is concluded that (1) Raw Materials Inventory control is highly needed by both small and big companies to take care of the production process stabilization; (2) The production process will find problems when there is no good control of the Inventory. This causes anstable production process effecting finnace of the companies. The long period of materials inventory causes campany loss. On the other hand, small amount of inventory will also cause the production processes stop. Such situation will also influence marketting and the supply to the consumers; (3) Unstable producation process will cause unstable product supply in the market, and (4) To ensure that the consumers ’ needs are continuously completed, control of the raw materials inventory needs to be done and maintained.

Improvement of Stamping Forming Process and Design of Fully Automatic Die for Lipstick Casing Pipe

According to its structure and dimension, the original stamping forming process of the lipstick casing pipe was analyzed. In view of such drawbacks as dispersed working procedures, lower efficiency and unstable product quality in the original manufacturing process, wall thickness of the lipstick casing pipe was modified and became thinner than its original size with the premise of ensuring utility performance. A new manufacturing process for the modified lipstick casing pipe was provided and a fully automatic stamping die, which is more secure in operation, lowers raw material expense and has higher production efficiency, was designed.

CHARACTERIZATION OF SORBENT PRODUCED THROUGH IMMOBILIZATION OF HUMIC ACID ON CHITOSAN USING GLUTARALDEHYDE AS CROSS-LINKING AGENT AND Pb(II) ION AS ACTIVE SITE PROTECTOR

Sorbent produced through immobilization of humic acid (HA) on chitosan using glutaraldehyde as cross-linking agent and Pb(II) ions as active site protector has been characterized. Active sorption site of HA was protected by reacting HA with Pb(II) ion, and the protected-HA was then activated by glutaraldehyde, crosslinked onto chitosan, and deprotected by 0.1 M disodium ethylenediamine tetra-acetic acid (Na2EDTA). The protected-crosslinking method enhanced the content of immobilized-HA and its chemical stability. Based on the FTIR spectra, crosslinking of HA on chitosan probably occurred through a chemical reaction. The sorption capacity of sorbent still remains unchanged after the second regeneration, but some of HA start to be soluble. The latter shows that cross-linking reaction between HA and chitosan is through formation an unstable product. The effectiveness of sorbent regeneration can also be identified by the XRD pattern.