Sealer thermodynamic parameter calculation

Source:   Date:2014-10-28 15:46:34   Views:

Packing high-speed sealing sealing and cutting machine cutting machine shearing energy derived from the cylinder gas expansion work. In the shearing process, acting to promote the expansion of the gas on the downward movement of the hammer, and through two-way cartridge valve drain quickly achieve high-speed sealing and cutting machine shearing. In the gas expansion into energy during combat, accompanied by energy loss. If the knife represents the mechanical efficiency of sealing and cutting machine cutting stroke, the sealing and cutting machine shearing energy expression is as follows:
Where We- gas expansion work, Jo
Desirable mechanical efficiency 77 0.8 a 0.85, but according to 71 experiments, the actual sealing and cutting machine up to about 0.9, so the design can be bigger value. Because sealer shear energy E is a given parameter, so the desired pair of gas expansion work according to the calculation.
Since the packaging speed sealer sealer cut very short time, the process was carried out quickly, so approximate that change is an adiabatic process gas. Therefore, the process of gas expansion work on this sealer first inflated, often inflated to the working cylinder mold in the lowest position on the sealing and cutting machine to cut, and then the gas enclosed in the working cylinder. When the mold return, the gas is compressed accumulator. This process is actually changing the process gas ranged between moderate insulation, etc., in order to simplify the calculations can be approximated by adiabatic calculations. In this process, the temperature of the gas will rise. Therefore, after the return of gas pressure and temperature of the working fluid are derived .V case by the thermodynamic temperature higher than room temperature. As the slider system immediately after the return sealer cut, the initial pressure of the gas inside the cylinder where, after a blow job cylinder pneumatic gas restored to its original state. If after the return, the pause period of the slider floating, working cylinder gas heat exchange with the outside, until the gas reaches room temperature T ,. In this process, the gas is actually the isochoric process, the pressure drop decreased with increasing temperature, the pressure of the gas after cooling:
In this case sealer gas pressure and temperature will be lower than the inflation pressure and room temperature. A 5- by Formula 3 Formula 3 - 7 working cylinder gas can be determined to reach the highest and lowest gas pressure and temperature. These parameters are related to the expansion ratio. Related. If the maximum temperature or minimum temperature of the gas exceeds the operating temperature range of the sealing material, it will affect the seal life. Thus considering these factors, the expansion ratio is 0.25-0.4 take appropriate design.
In determining d, to be considered a return sealer liquid pressure and liquid flow return, if the value of d is small, the return pressure is low, large flow; if d greater the value, the higher the return fluid pressure, low flow. Algorithm design by trial last words to determine the value of a combination.