Research
Overview of a Knit-Dyeing Factory with Necessary Production Formulas
Different processes associated with complete production of fabrics are discussed briefly in this paper. An effort is made to formulate all the production steps. This paper also gives an idea of different processes and machineries used usually in a fast growing and mass productive knitdyeing factory. Major processes in all machines are discussed briefly. Different important parameters in different machines are also stated here. This paper tries to gather all the information related to knit-dyeing factory shortly. A helpful estimation of machine capacity for required production amount can be perceived from this paper. Also the existing efficiency of different processes can easily be calculated from different mathematical formulas stated here.
Optimum Design of Compound Pressure Vessel
Effect of compounding investigated theoretically by finite element modeling. The variables are interference radius & shrinkage tolerance. Equivalent von Mises stress is used as yield criterion to evaluate the optimum interference radius. For two different working pressure the effect of the ratio of outer & inner radius (b/a=k) value on the optimum interference radius is also noticed. The optimum interference radius solely depends on shrinkage tolerance. Furthermore, percentage reduction of von Mises tolerance is compared for different working pressures & different k values as well as for different materials.
Optimum Design of Autofrettaged Thick-Walled Cylinders
The effect of autofrettage process on thick-walled cylinders has been investigated here. It is observed that flow stress distribution along the cylinders remains same for same k values. Comparison with Zhu & Yang’s model has been also done in determination of optimum elasto-plastic radius, ropt and optimum autofrettage pressure, popt. Equivalent von Mises stress is used as yield criterion. It is observed that percentage of reduction of maximum von Mises stress increases as value of k and working pressure increases. Maximum von Mises stress is minimum for lower working pressure at same value of k and autofrettage pressure. Autofrettage process never starts if autofrettage pressure does not exceed working pressure. It is also observed that two limits of autofrettage pressure Py1 & Py2 are not appropriate. Effect of loading stages on autofrettage process is also investigated. As long as the pressures in first and last stage remains constant, there is no effect of loading stages on autofrettage process; no matters how many stages prevails between these two pressures.
