scholarly journals Review on the Methods for Measuring the Moisture Content of Green Sand

Author(s):  
GAO Guili ◽  
SHI Dequan ◽  
DONG Jingwei
Keyword(s):  

2013 ◽  
Vol 380-384 ◽  
pp. 806-810
Author(s):  
De Quan Shi ◽  
Gui Li Gao ◽  
Jing Wei Dong ◽  
Li Hua Wang

In order to solve the nonlinear output/input problem of the capacitance method measuring the moisture content of green sand, a nonlinear compensation is added into the measurement system and the neural network is used for nonlinear rectification. Based on introducing the principle of non-linear compensation, a functional link artificial network with multi-input and single-output is constructed. In the network, the output voltage of capacitance moisture sensor is taken as the input and the moisture content of green sand is taken as the output. The data samples obtained in laboratory are used to train the network, and the dynamic rectification model is got. The experimental results show that the maximum difference and relative error of the moisture content are ±0.09% and ±1.85% after nonlinear rectification by the functional link neural network, and it is significantly better than those of the least square method.



2012 ◽  
Vol 445 ◽  
pp. 859-864 ◽  
Author(s):  
A. Abdullah ◽  
Shamsuddin Sulaiman ◽  
B.T. Hang Tuah Baharudin ◽  
Mohd Khairol Anuar Ariffin ◽  
T.R. Vijayaram ◽  
...  

Permeability and green compression strength are among the important mechanical properties and considered much in the sand casting mould preparation. These molding sand properties play a vital role in determining the optimum moisture content for making green sand casting mould. Tailing sand is the residue mineral from tin extraction, which contains between 94% and 99.5% silica and in abundance in Kinta Valley of state of Perak, Malaysia. In this research work, samples of tailing sands were gathered from four identified ex tin mines located at the Perak State, Malaysia. They were investigated by the standards and testing procedures prescribed by the American Foundrymen Society (AFS). Sand specimens of size Ø50 mm×50 mm in height from various sandwater ratios bonded with 4% clay were compacted on applying three ramming blows of 6666 g each by using a Ridsdale-Dietert metric standard rammer. The specimens were tested for green compression strength using Ridsdale-Dietert universal sand strength machine and permeability number with Ridsdale-Dietert permeability meter. Before the tests were conducted, the moisture content was measured using moisture analyzer. Samples with moisture content ranging from 3 to 3.5% were found to have optimum working range with effective green compression strength and permeability.



Author(s):  
B. Chokkalingam ◽  
M. Priya ◽  
R. Immanual ◽  
B. Varun

The primary objective of this work is to reduce blowhole defect occurring in a cast iron transfer box. The transfer box moulds were produced using green sand moulding process, and cores were made using CO2 process. It was found that the transfer box had a rejection rate as high as 60%, and it was mainly due to a blowhole on the top surface of the casting. The Ishikawa and risk Ishikawa diagrams were used to analyze this major defect. The risk Ishikawa diagram was constructed by assigning weights to the major and sub-causes due to which the defect occurs. Further, the probability of risk and its impact values were employed to compute risk scores for the main causes and also global risk. From the work carried out, it was found that that the moulds and the sands along with melting and pouring parameters were the major causes for this defect while damp chill, pouring delays and high moisture content in sand were identified as the root causes for the blowhole defect. The main root cause for the blowhole defect was pouring delay that eventually causes dampness in the chill pieces kept inside the moulds. The remedial measures of keeping the moisture content of the sand within 3.5% and pouring the moulds in the shift II within half an hour after closing them were implemented to eliminate it.



Author(s):  
Nanang Qosim ◽  
AM Mufarrih ◽  
Ali Sai’in ◽  
A. Hanif Firdaus ◽  
Fina Andika F. A. ◽  
...  

In this study, three percentages of moisture content on the green sand were benchmarked to be observed their effects on the casting defects. The metal used is scrap Al-Si with wt% of Al 59.7. The metal was melted in a furnace at 550 ºC then poured into sand molds and cooled for 24 hours before it can be removed, cleaned, and finished. There were prepared three specimens for each benchmark. Qualitative observation of defects was done by physical observations on the surface of the specimens. The observations show that on the moisture content of 2.5%, there is a defect in the form of porosity. Defects in the form of drops, misruns, blowholes, and shrinkage cavity are found on the benchmark 3.5%. The most severe defects are found on the benchmark 4.5% in the form of buckles and severe shrinkage cavities that are found in almost all specimens.





2013 ◽  
Vol 773-774 ◽  
pp. 211-217 ◽  
Author(s):  
Azhar Abdullah ◽  
S. Sulaiman ◽  
B.T.H.T. Baharudin ◽  
M.K.A. Ariffin ◽  
N. Haliza

Tailing sand from ex-tin mine in Batu Gajah containing between 95.9 to 98.9% silica. In this research involved the process of, conducting the mechanical sieve grading to identify the size spread, plotting the grain size distribution and calculating the average grain size. Further on with the effects of controlled additions of clay (bentonite) and water and determining the working range on the mechanical properties. The investigation involved comparing the mechanical properties of the tailing sand to the requirement for foundry sand applications listed by Foseco Ferrous Foundrymans Handbook (Foseco). Permeability and green compression strength are the important mechanical properties and considered much in the sand casting mould preparation. These mechanical properties play a vital role in determining the allowable clay and moisture content for working range of tailing sand for making green sand casting mould. Experiments for this investigation were conducted according to American Foundrymen Society (AFS) standard of procedures. Cylindrical test pieces dimensioning of Ø50 mm×50 mm in height from various sandwater ratios bonded with 3.8%wt clay and then 7.4%wt clay, were compacted by applying three ramming blows of 6666 g each using Ridsdale-Dietert metric standard rammer. The specimens were tested for green compression strength using Ridsdale-Dietert universal sand strength machine and permeability number with Ridsdale-Dietert permeability meter. Before the tests were conducted, the moisture content was measured using moisture analyser. Tailing sand with allowable moisture content ranging from 3 to 3.5% (bonded with 3.8%wt clay) and 5.5 to 6% (bonded with 7.4%wt clay) were found to have optimum working range with effective green compression strength and permeability.



2021 ◽  
Vol 6 (2) ◽  
pp. 131-141
Author(s):  
Kingsley Okechukwu Ikebudu ◽  
Swift Kenneth Onyegirim ◽  
Philip Ifchukwu Udeorah

Quality of cast produced from green sand mold is been influenced by mold properties which includes green compression strength, permeability, etc. In this work the green sand used for casting of aluminum 6351 alloy specimens were made by mixing in varied percentage proportions; bentonite clay, dextrin additive and moisture content with local silica sand considering the need for most effective proportions of these mixtures to enhance green sand production of aluminum 6351 alloy products. A 3 factor, 3 level (33) design of experiment (DOE) was made for this research work using Optimal (custom) design of Design-Expert 10 software which gave 20 runs. Cylindrical specimens for green sand test were prepared according to standard per run. This was in order to study effects of bentonite clay, dextrin additive and moisture content of the green molding sand used for casting per mold this aluminum 6351 alloy. Prepared sand specimens were individually subjected to basic sand test like green sand strength and permeability test and also cast specimens per mold achieved were subjected to mechanical property test to achieve results which become the Response output of the study. These experimental results were optimized for the purpose of achieving most effective proportions of the mixtures to give effective results and from the optimal validation values, 5% water content, 12% bentonite and 8.85182% dextrin organic additive was found to be the optimized solution that gave the most effective hardness at (40.4GSS and 112PN) while 3% water, 12% bentonite clay and 9% dextrin additive gave most effective toughness at (41.9GSS and 96.10PN).



1968 ◽  
Vol 19 (03/04) ◽  
pp. 423-429 ◽  
Author(s):  
G. M Thelin ◽  

SummaryA stable, lyophilized AHF reference plasma has been prepared from pooled plasma from at least 50 normal healthy donors and standardized against a primary standard of fresh plasma from 20 healthy male donors aged 20 to 40. Average AHF potency of a typical lot is 98.8%, and moisture content is less than 0.5%. Under storage at -25° C, this AHF reference plasma is stable for at least 18 months. It has been used in several major coagulation laboratories, and has given consistently satisfactory and reproducible results in AHF assays.



1977 ◽  
Vol 27 (1) ◽  
pp. 30-32
Author(s):  
Kaissar M. Hanna ◽  
Ahmed El Gamal


Sign in / Sign up

Export Citation Format

Share Document