Influence of the Polymer Addition in Quenching Water on the Deformation and Residual Stresses of Aluminum Alloy Sheets

The quenching is one of the most used mechanisms for increase the strength of aluminium alloys sheets. The purpose of quenching is to keep the super-saturated solid solution formed during the solution heat treatment as intact by rapid cooling. In order to establish the influence of the addition of polymer in the quenching water on the distortion and residual stresses of the aluminium alloy sheets, several tests were performed with different concentrations of the polymer in demineralized water. The experiments were performed on 6082 aluminium alloy sheets with a thickness of 5 mm. The quenching of the samples was done by immersion in a stainless steel vessel with a capacity of 10 liters. The obtained results show that the addition of polymer in demineralized water positively influences the deformation of aluminium alloy sheets. In this way, a correlation between the polymer concentration and the deformation of the plates was established. Regarding the internal stresses, no correlation was identified with the level of polymer used in demineralized water.

Pharmaceutical Standardisation of Devdarvadyarishta w.s.r to the Fermenting Vessel

Standard operating procedure for pharmaceutical preparation of Devdarvadyarishta has been developed in the present research work. A pilot scale study having 3 batches was carried out initially to find out the best possible fermenting vessel among glass jar, porcelain jar and stainless steel vessel and also to investigate for any possible hurdle related with fermentation process as honey and not jaggery is used as sweetening agent in this formulation. Three samples of Devdarvadyarishta as per conventional method were prepared in accordance with Bhaishjya Ratnavali and process for standard of Devdarvadyarishta was set in as a Quality specification for the same. Porcelain jar was found to be the best as per the results of pilot study as evident by alcohol content of 5.73%, 6.25% and 6.10% respectively in glass jar, porcelain jar and stainless steel vessel, the reaction being completed in between 38-47 days. Approximate duration of Kwatha formation in all the batches was 9 hours with peak temperature during boiling being maintained at 920C. In all the three batches, fermentation started on 7th day, 7th day and 9th day, total duration of fermentation was 72 days, 70 days and 75 days, with % loss of 15.78%, 17.76% and 19.07% respectively. Mean % loss observed during preparation was 17.53%.

Effect of Microstructure of Surface Layer in Steel Vessel Used for Sponge Titanium Manufacturing on Fe Elution

To make clear factors affecting Fe elution into molten Mg during sponge titanium production process and reasons why Fe elution from the steel vessel in the first use is high while it considerably reduces in the second use in the actual mill, immersion experiments into molten Mg at 950ºC were conducted using specially designed specimens simulating the first and the second uses of the vessel, and microstructure change of the steel during the use was investigated in detail. TiFe, TiFe2 and Ti-diffused steel layers formed on the surface of the steel specimen after the treatment similar to the first use of the vessel. The outermost portion of Ti-diffused steel contained 3mass% Ti, which should have transferred to the α phase at this temperature. Fe elution from TiFe and TiFe2 was almost zero, while Fe elution from Fe-3mass%Ti was 1/4 of that from the unused steel. By taking the information on the phases appeared on the surface of the actual vessel into account, Fe elution from the vessel at the second use was estimated as 1/16 of that at the first use, which is well consistent with the value in the actual production mill.

Comparative analytical study of Ashuddha Karaveera and Shuddha Karaveera

Karaveera (Cerebra thevetia Linn.) is reported under Upavisha Dravya in classical ayurvedic pharmacopeias. It is observed that Shodhana (purification procedures) of the mool should be carried out before its internal administration. There are different Shodhana methods mentioned in Ayurveda. In this study Godugdha was used as media. The impact of Shodhana was evaluated by physico analytical study. It clearly proves physico analytical changes during Shodhana. Ashuddha Karaveera was taken on white clean cloth and they dumped in Pottali with Godugdha. Pottali was tied to middle of wooden rod dipped in Godugdha in stainless steel vessel and mild heat given to pottali in Dolayantra. Shuddha Karaveera was obtained and then washed with leuk warm water and dried. Ashuddha Karaveera contains toxin in it which was removed after Shodhana process. So that foreign matter, loss on drying was less in Shuddha Karaveera and due to Shodhan process with Godugdha total ash, acid insoluble ash was more than that of Ashuddha Karaveera.

Water Level Sensing in a Steel Vessel Using A0 and Quasi-Scholte Waves

This paper presents a water level sensing method using guided waves of A0 and quasi-Scholte modes. Theoretical, numerical, and experimental studies are performed to investigate the properties of both the A0 and quasi-Scholte modes. The comparative study of dispersion curves reveals that the plate with one side in water supports a quasi-Scholte mode besides Lamb modes. In addition, group velocities of A0 and quasi-Scholte modes are different. It is also found that the low-frequency A0 mode propagating in a free plate can convert to the quasi-Scholte mode when the plate has one side in water. Based on the velocity difference and mode conversion, a water level sensing method is developed. For the proof of concept, a laboratory experiment using a pitch-catch configuration with two piezoelectric transducers is designed for sensing water level in a steel vessel. The experimental results show that the travelling time between the two transducers linearly increases with the increase of water level and agree well with the theoretical predictions.

Steel-Concrete Composite Vessel for Stationary High-Pressure Hydrogen Storage

A novel Steel Concrete Composite Vessel (SCCV) was designed and engineered for stationary high-pressure gaseous hydrogen storage applications. SCCV comprises four major innovations: (1) flexible modular design for storage stations for scalability to meet different storage pressure and capacity needs, flexibility for cost optimization, and system reliability and safety, (2) composite storage vessel design and construction with an inner steel vessel encased in a pre-stressed and reinforced outer concrete shellshell, (3) layered steel vessel wall and vent holes to address the hydrogen embrittlement (HE) problem by design, and (4) integrated sensor system to monitor the structural integrity and operation status of the storage system. Together, these innovations form an integrated approach to make the SCCV cost competitive and inherently safe for stationary high-pressure hydrogen storage services. A demonstration SCCV has been designed and fabricated to demonstrate its technical feasibility. Capable of storing approximately 89 kg of gaseous hydrogen at 6250 psi (430 bar), the demonstration vessel was designed to include all major features of SCCV design and fabricated with today’s manufacturing technologies and code/standard requirements. Two crucial tests have been performed on this demonstration vessel. A hydro-test was successfully carried out to 8950 psi per ASME VIII-2 requirements. The cyclic hydrogen pressure test between 2000 psi and 6000 psi is currently being performed to validate its use for high-pressure hydrogen storage. Multiple sensors, such as pressure sensors and strain gages, were incorporated in the demonstration SCCV to collect information to validate the design and operation of SCCV. Key design parameters and test data on its performance are summarized in this paper.