Development of hydraulic cross floating valve.

ABSTRACT

This paper describes the design, simulation, development, and analysis of a Cross Floating Valve (CFV), an important instrument used in a cross float or pressure calibration system of pressure balances (PBs) to make the calibration process easy and time efficient. The design aspects of the CFV include the selection of proper materials and modeling of various necessary components of the CFV. For the piston design, 5 different materials, SS304, SS316, Aermet 340, SS440C, and AISI17-4PH were used. After the design, simulation studies were carried out using the ANSYS (Workbench R15.0) software to understand the behavior of stress, strain, and deformation. Out of the 5 materials thus used, the values of the factor of safety of 2 materials (SS304 and SS316) were found to be below expectations and hence were not used in the fabrication process. Among the rest of the 3 other materials (AISI17-4PH, SS440C, and Aermet 340) having a factor of safety within the expected limits, Aermet 340 was also ignored because of its high cost. Finally, AISI17-4PH and SS440C were used to fabricate the piston, the most important and critical component of the CFV. The final CFV thus developed was tested for its performance in the cross floating experiments with 2 different sets of PBs. The results thus obtained show that the use of CFV reduces the calibration time considerably which is approximately 30% (average time of increasing and decreasing orders of pressure) from the time taken in performing calibration without using CFV, which is a significant achievement.