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This paper aims at the problem of spot-shaped defects caused by the cleaning process of the profile of 2196 Al-Li alloy, Fluorescence detection combined with metallographic microscope was used for detection, The results showed that the pitting and intergranular corrosion were observed in the pitting defects. Therefore, it is proposed to simulate each cleaning process, analyze the defect morphology generated under different states, and explain the cause of defect formation. The final test results showed that water washing, pickling and water immersion exposure could lead to pitting and intercrystalline corrosion of 2196 Al-Li alloy. Thus, it was analyzed that the defect was caused by the formation of AlCl3 and Al (OH) 3 products after the sample reacted with liquid during the cleaning process. When these two products are more concentrated, The grain boundary is subjected to tensile stress due to volume expansion, It leads to point-like defects in al - Li alloy along grain boundary.

In the continuous pickling line, the acid temperature setup accuracy was low, which not only caused excessive pickling defects, but also caused excessive consumption of hydrochloric acid and a decrease in pickling efficiency. In order to solve this problem, the acid temperature setup model based on case-based reasoning (CBR) technology was established by using a large amount of production data with good temperature setting precision. After the model was put into operation on a 1450mm pickling and rolling line, the average pickling defect ratio decreased from 14.99904% to 11.7332% and the fluctuation range of the pickling defect ratio was effectively controlled. Practical application showed that the setup accuracy of the acid temperature model was effectively improved. As the number of strip steel production increases, the model has the adaptive ability to change with the working conditions, which is suitable for industrial promotion.

Manganese-zinc soft magnet material is made of waste iron red produced by cold rolled steel plate pickling and new slag of cold rolling mill as the main raw material, and sintered with a certain proportion of manganese trioxide and other additives. As the production material of magnetic core, its inherent material characteristics make it easy to occur in the process of machining, such as lacking of angle, crystal spot, crack and other undesirable phenomenas. In this paper, an automatic core detection equipment based on machine vision is designed, and the image of the core is obtained by multi-station shooting. After filtering and feature extraction, it can replace the manual detection of whether the core is defective or not. According to the experimental result, the device can save 23% detection time, and then reduce the production cost.

This paper presents a implementation of acid concentration model based on multi-step prediction recurrent neural network (MSPRNN) for a steel pickling process. The MSPRNN for predicting the values not in only one-step future but in multi- step future is applied to predict the acid concentration in the steel pickling process. The basic MSPRNN is a recursive structure predicting the multi-step future targets using the distant past inputs and the previous predicted targets. On the other hand, the proposed MSPRNN is a structure that predicts the multi-step future targets using distant past inputs and distant past targets. Even though the nonlinearity is strong because of the large time difference between the available inputs and the targets to be predicted, the proposed MSPRNN maintains robust prediction of the acid concentration in the multi-step future.

The quality of welding seam has been an obstacle of automatic and efficient production. Among them, speed of the welding trolley is an important factor affecting the quality of welding. In this paper, the fuzzy control of the welding trolley is adopted to make the driving of the trolley more stable and reduce the interference caused by the startup and stop of the motor, frictional force change of the ball screw, change of resistance in the walking process and the like. Speed change can be traced and its effect on the welding quality tends to be minimized, enabling the automation of the mill's production to be further improved. Since this project is based on the modification of the old B & R positioning system for the laser welding machine in pickling section of the cold rolling mill, Siemens S7-300 PLC program is used instead of the original B & R positioning system for position control in this project. Fuzzy control of welding trolley speed is applied to Siemens PLC program in order to realize its function and carry out corresponding research in this paper.

Polymer compounds are found to offer excellent corrosion resistance to metals when exposed to acidic environment during acid pickling, acid descaling and industrial cleaning. Though, numerous problems emerged with the use of inorganic inhibitors due to their environmental threat to the environment. Owing to these problems, the use of organic green inhibitors (leaf extracts) came into limelight. However, many of these inhibitors decompose easily when subjected to elevated temperature which in turn reduces the efficiency of the inhibitors. In order to overcome some these aforementioned problems, synthetic polymers were found as an alternative. Vast research has been investigated and reported on the use of synthetic polymer compounds as corrosion inhibitors. The performance of these polymers is largely dependent on the moieties, molecular weight and composition associated with the molecular structure of the compound. -NH2-, -COOH-, -OH- and many more moieties block the active metal sites by the large film formed on the metal surface. This paper gives an overview of the behavior of synthetic polymers as corrosion inhibitors in acidic environment.

There are so many types of steel products in the market, making up various shapes, grades, specifications, finishes, etc. The process used to improve the coil surface finish and to size the cold roll sheet perfect is by chemical, mechanical descaling and polishing. When producing Cold roll sheets there are some or minor defects on the surface sheet cannot be easily inspected by the human eye because of the machine high speed rolling. In order to inspect the surface quality of the sheet, the online inspection must be implemented to meet the performance of the QC inspection standards. Many researchers have already worked on the defect detection on Cold Roll Sheets and proposed different techniques but in this research, we have worked on the over and under pickled defects of sheet related to color changes and scratch detection through Line Profile Analysis.

In this paper, the application of independent component analysis (ICA) to statistical process monitoring is studied. This paper mainly focuses on studying on the fault detection and isolation principle based on the data model of ICA. Contributions of this paper are: (1) for the purpose of fault detection, two monitoring statistics are designated by detailed analysis on the data model of ICA; (2) a semi-supervised Laplacian regularization (SLR) kernel density estimation approach is proposed to determine the normal operation region; (3) Under fault condition, a fault isolation method based on expert knowledge is introduced; (4) Hot Galvanizing Pickling Waste Liquor Treatment Process (HGPWLTP) is taken to evaluate the monitoring performance of the proposed approaches. Encouraging experimental results of the proposed process monitoring approaches are achieved.

Hexavalent chromium Cr(VI) has been widely used in metal pickling and plating, which induces cancer and coetaneous allergy in the long time exposure. In this work, a novel thin film composite hollow fiber nanofiltration (NF) membrane was developed, which was optimized by time of interfacial polymerization, concentration of monomers and the IP process. In addition, operational conditions, including PH values, temperatures and operational pressures on the NF performance was further investigated to exhibit potential application in the industrial wastewater treatment and obtained resultant water for biomedical use.

The production increase of a continuous processing line is directly related to an increased processing speed of the material. In this context, this work presents a technical analysis involving the various equipment of a continuous annealing and pickling line of steels, focusing on the characterization and possible expansion of its speed limit. Based on the working fundamentals and operational characteristics of the equipment of each line section, it was identified its maximum capacity concerning the highest running speed achievable. The results indicated that the accumulation lengths of loop cars, speed and power capacity of electric motors, furnace heat and electrolytic pickling capacity are not on their edge limits, pointing to the possibility of significant speed gains. Step-down gearboxes, on the other hand, proved to be undersized, indicating the need for re-powering, even if they are to operate on the current speed. Apart from the gearboxes, the next speed limitation was imposed by the electric motors; however, they still can deliver a speed increase of 17 meters/minute. It is worthy mentioning that the evaluation methodology proposed here can also be applied to other types of production lines, which can also be optimized.

The speed optimization (SO) control technology used in the pickling line and tandem cold mill (PL-TCM) is introduced. Based on characteristics of the speed control at each section of the PL-TCM, its optimal speed control was ascertained according to the speed control principle and SO strategy. With the loop capacity control principle and stability strategy, the line's speed was controlled smoothly, which is helpful for improving strip's quality and quickening the production rhythm. The production results indicate that the output of cold strip has been increased and its shape quality has been greatly improved with the SO control technology.

Sepiolite has excellent absorbability and fine thermal capacity, and the elements like magnesium and silicon are possess are themselves excellent halogen-free flame-retardant, and are nontoxic, harmless and abundantly available, presenting great potential in flame retarding and smoke suppression. In this paper, sepiolite was added in poplar wood flour after it was treated by water or acid, and then compressed into boards. CONE and TG-DSC were used to analysis the combustion properties, smoke-release properties, and charring characteristics of samples. Further study on the synergistic function of acidified sepiolite and K2CO3/ Mg(OH)2 on flame retarding and smoke suppression was also conducted. Results show that sepiolite can effectively reduce the heat release rate (HRR), total heat release quantity (THR), smoke produce rate (SPR) and total smoke release quantity (TSR) of the Poplar wood flour, showing remarkable effect on flame retarding and smoke suppression. While modified sepiolite extends a even superior effect, mainly because that with acid pickling and water washing, impuritie in the sepiolite have been eliminated and channels been dredged to enlarge the surface area and improve the absorbability of the sepiolite. Moreover, the acidified sepiolite and K2CO3/ Mg(OH)2 share an excellent synergistic effect on flame retarding and smoke suppression.

The adsorption behavior of Cr3+ and Fe3+ on 001×7 strong-acid cation exchange resin was studied with the static method, respectively getting Adsorption Isotherms of Resin 001×7 for Cr3+ and Fe3+. The experimental results show that, in the studied concentration range, the equilibrium adsorption data of Cr3+ fit to Langmiur isotherms, while Fe3+ fitting to Frendlich isotherms. Kinetic analysis show that the adsorption rate of Cr3+ is mainly governed by liquid film diffusion and the rate of Fe3+ is governed by Particle diffusion. In addition, the thermodynamic parameters were obtained from analyzed dynamics data and thermodynamic function. The conclusion indicates that the adsorption gets more orderly and is an exothermic process running spontaneously, so that higher temperature is bad for the reaction.

In order to reduce the operational cost and completely eliminate Fe2+ ion in the original acid-cleaning fluid for the wastewater treatment process of steel factories, a modified process of two-stage counteract/aeration oxidation is applied. Our results indicate that the effluent quality is better to the first class criteria specified in Integrated Wastewater Discharge Standard (GB 8978-1996). Furthermore, all of the effluent can be used as ground washing water.

Pickled mustard tuber is a traditional Chinese food preserved by high-salinity pickling process. A cleaner production technique of pickling mustard tuber process has been widely focused on the pickled fermentation with a low salt concentration. The objective of this present study was to determine the microbial community structure and its predominant functional species by single strand conformation polymorphism (SSCP) profiles under the optimizing pickling conditions with low salinity. Effects of SSCP conditions on gel electrophoresis assay as well as changes of lactic acid bacteria (LAB) population were also investigated. Results: Twenty two percent of gel concentration and addition of 6% glycerol in gel preparation for electrophoresis separation were ideal conditions for SSCP analysis of microbial community in pickled mustard tuber. The pH value in leaching liquid was descending throughout the pickling process and the total LAB population increased, reached the peak of 7.51 log cfu mL−1 at day 10 by plate counting then decreased gradually until to a stable level. With the optimal SSCP technique, 11 distinct dominant bands were obtained throughout the fermentation process of mustard tuber. Based on the sequence comparison the results showed that Leuconostoc mesenteroides was the predominant microorganism in the initial stage of fermentation. Then the Lactobacillus plantarum and Lactobacillus brevis appeared quickly. At the later stage, the predominant species were Lactobacillus plantarum and Lactobacillus versmoldensis. Conclusions: SSCP technique is a feasible method for microbial community analysis in pickled mustard tuber. Gel concentration and addition of glycerol in gel for electrophoresis operation had influences on the SSCP pattern performance for microbial community analysis of pickled samples. The contribution of some dominant LAB species was confirmed by SSCP method under the optimized processing condition of pickled mustard tuber.

The thermodynamics and kinetics on adsorption of Cr, Fe and Ni by activated carbon from stainless pickling wastewater are studied. The results show that the adsorption capacity of Cr, Fe and Ni are 8.198, 1.629 and 2 mg/g, respectively. The Freundlich isotherm model can fit the multi-component system better than the Langmuir isotherm, while the Langmuir - Freundlich equation is the best choice to fit them. The equilibrium times are 120, 60, 90 min, and the pseudo-second-order equation can fit the adsorption well. The results indicate that Cr is mainly chemically adsorbed on activated carbon with ion exchange adsorption, while physical adsorbption dominants the adsorption of Fe, and Ni is mainly of ion exchange adsorption.

Montan wax is unstable because of unsaturated link. Sulfuric acid is selected to saturate montan wax, and this would exploit its application. These were researched that the influence of the reaction time, reaction temperature and sulphuric acid concentration on montan wax, and the functional groups of waxes modified in different condition by FTIR. The results indicate that, the trend of recovery rate of montan wax is linearly reduced with the reaction time, reaction temperature and the sulphuric acid concentration. Moreover, this modification can benefit for the introduction of aromatic, aliphatic and olefins to montan wax with the increasing of the reaction time, reaction temperature and sulphuric acid concentration.

stainless steel is used as raw material and pickling in HCl-based electrolytes is adopted, and the effect of pickling temperature on removal behavior of the oxide layer on stainless steel is systematically studied, study found that the oxide layer of stainless steel after heat treatment in the lab is composed of Fe2O3 and Cr2O3, at different temperatures, with the increasing of duration, corrosion potential of stainless steel after heat treatment shows fall followed by rise, and corrosion potential of stainless steel in 60°C is obvious higher than in 50 °C; with temperature increasing, the weight loss of stainless steel after pickling increase with large range, and the weight loss of the oxide layer of stainless steel increases as the duration increases.

Titanium alloys are commonly used in biomedical application in hard tissues replacement especially for knee and hip implants but facing huge wear debris due to continuous cyclic contact within the joints of the implants. Diamond coating is a potential solution for improving the tribological and wear properties of the implants made from this alloy. Diamond is known for having high wear resistance property and chemical vapour deposition (CVD) is one of the most promising methods for diamond coating. However, the major concern for CVD process is the poor adhesion of the diamond to the substrate material due to the large mismatch of coefficient of thermal expansion (CTE) properties between the two. A suitable interlayer material can be introduced to reduce the gap of CTE differences by oxidation process. In this study, the effect of pickling temperature and mechanical surface treatment methods on the adhesion strength of Ti oxide interlayer prior to diamond coating were investigated. Besides, the thickness of oxide layer and surface morphology were also evaluated. Experiments were carried out on Ti6Al4V substrate by varying the surface treatment pickling temperature from 25°C to 50°C. In mechanical surface treatment, all samples were ground using #220 to #1200 grits and followed with polishing using alumina paste. After the surface treatment process, all the substrates underwent thermal oxidation for 25 hours at 900°C. The results showed that the adhesion strength of oxide layer increases with the increasing of pickling temperature. Mechanical surface pretreatment provides better adhesion of oxide layer than chemical pretreatment (pickling process). However, the adhesion strength decreases with the increases of oxide layer thickness.

This study attempted to find the adsorption law of fly ash to COD in domestic sewerage. After the elementary characterization of fly ash was described, the influence of contact time, sorbent concentration, and different pretreatment ways of fly ash, initial COD concentration and temperature on the adsorption process was investigated. Results showed adsorption equilibrium attained within 120 min time. Freundlich adsorption isotherm model fitted the experimental data better than Langmuir model. The treatment efficiency improved if fly ash was pretreated through pickling or washing. The adsorption capacity of fly ash to COD decreased with rise of temperature, which showed that the adsorption process was an exothermal process.

The Paper has exploited a system of on-line monitoring and fau1t diagnosis for pickling and cold-rolling electric drives, making use of configuration technologies, Matlab simulation tools and BP neural network. Based on the theory of BP neural network, a fault diagnosis model is designed, which is for electro-hydraulic servo valve, the key execute machine of pickling and cold-rolling electric drives. The model is directed at analyzing the fault possibility and fault type of electro-hydraulic servo valve. After tests on the well-trained BP-based fault diagnosis system, the system proves to have the ability of diagnosing any type of fault of electro-hydraulic servo valve accurately. The result of experiment gives the evidence that this method is very efficient for fault diagnosis system for pickling and cold-rolling electric drives.

Mixed acids which consists of HF, HNO 3 ard used as good etchant for pickling process of stainless steel and of HNO 3 , CH 3 COOH, H 3 PO 4 are used as etchant for aluminum. The optical detection of concentration for such mixed acids is important to optimize and cut costs in the acid pickling process. The Raman spectroscopy technique has been employed to measure the concentration of mixed acid component within the aqueous phase.

The objective of this study is to estimate the efficiency of laser cleaning for oxide layer and monitor the concentration of each acid for the pickling liquor under existing steel-pickling process. It was carried out that laser removal of surface oxides and small particles from steel surfaces by using a Q-switched Nd:YAG laser. In order to optimize and cut costs, it is important the optical detection of concentration for mixed acids in the pickling process. For this reason, we studied the cracks through electrochemical laser process and measure components of surface by using Raman Microscopy and measure the concentrations of mixed acid by using NIR spectroscopy.

In this paper, we present a system to detect and measure the amount of residual oxide stains remaining in the surface of stainless steel coils after the pickling process in a production line. The system is able to acquire clear images of the stainless steel surface with the appropriate illumination and magnification, while it is being produced. These images are processed and analyzed in real time in order to detect and measure the oxide stains which typically are between 50 and 200 microns in size. We present here an outline of the acquisition system and the image processing algorithm which has been designed to detect this sort of defect.

Two detection methods, magnetic and ultrasonic method, were compared to detect a defect that is located in and on the steel strip. The main composition of that defect is non-metallic oxides. We can select a proper method of detection according to the purpose of detector installation, the strip thickness, and the line speed. Magnetic flux leakage method is one of the promising methods for a very thin steel strip. On the other hand, the guided ultrasonic wave is very useful on for the thin steel strip such as the strip in pickling line.

A new ultrasonic immersion testing method for the detection of internal flaws in a running steel strip has been developed. An ultrasonic detecting system using this method has been installed in No.6 Pickling Line at Kawasaki Steel Chiba Works. It is confirmed that an inclusion with 5 /spl times/ 10/sup -5/ mm/sup 3/ in the minimum volume in running steel strip can be detected with signal-to-noise ratio in the range of 9- 10dB.

The paper presents a mathematical model of a turbulence pickling line, designer! to remow the oxide layer, known as scale, from a plain steel strip by means of a pickling medium, e.g. hydrochloric or sulphuric acid. The constituent parts of the installation and the differential equations describing the processes that take place inside of them, as well as effects encountered during the pickling process are overviewed. Further on, a simplified process model is described. Based on this, an adaptive control algorithm is developed. Simulation results and conclusions round up the presentation.