For the needle valve sealing cone bottom diameter of 0.3 mm, the load P₠is 228 ± 1.4 N, representing the elastic force at full lift. Internal boring machine oil injection and control are managed with a pressure of PZ = 12.55 (x 10^0.7) × 9.8315 ± 15.5 N. The relationship between the spring shear stress T and the spring parameters is given by T = (SPIDK7rd³)/2, which equals 523.5 N/mm². The shear stress r is 23.5 N/mm². When the number of load cycles N reaches 10, the r.Ac line represents the maximum stress line and is equivalent to the torsional yield limit.
Starting from the origin, the ray r-i is used to locate the working stress point E on the line. The intersection of this ray with the AC line at point G defines the limit stress point under an asymmetric cycle. From the similar triangles △AGH and △CGF, it can be seen that the ultimate stress of the projectile is determined. The maximum stress distribution is 13.85, corresponding to a value of 723.5 N/mm². The asymmetric cyclic stress of the spring has a constant cycle characteristic, where the minimum stress is 0.7238 times the maximum stress.
The limit of the asymmetric cycle should be evaluated, and the maximum stress value for the asymmetric cycle characteristic r is considered. The ultimate stress rlim for the asymmetric cycle can be determined using the Goodman limit stress diagram. The point C, located at 1079 N/mm², represents the material's torsion strength. The OC line makes a 45-degree angle with the abscissa and represents the minimum stress line. Since the minimum and maximum stresses are equal on this line, it is referred to as the static stress line.
Point A on the vertical axis represents the material’s pulse fatigue limit, set at 506.6 N/mm². The coefficient of variation of the ultimate stress and the material strength is considered in the calculations. Similarly, the standard deviation of the asymmetric cycle’s ultimate stress is calculated using the formula S = u0.014, resulting in Sr = 12.293.
In the actual manufacturing of springs, shot peening and strong pressure treatment are commonly used to enhance the fatigue strength of the material. The shot peening diameter typically ranges between 0.75 and 1.0 mm, with 0.8 mm being a common choice. Shot peening is generally done using steel media. During the projectile process, the speed of the projectile is between 50 and 84 m/s, and the fatigue strength of the spring is improved after shot peening.
Strong pressure treatment of the spring increases its strength by up to 535% under the same working conditions. Data shows that after shot peening and strong pressure treatment, the fatigue strengthening coefficient k is approximately 1.3. Using a Z-table, it is evident that the reliability R > 0.999999 is achievable, with F1 - R < 1×10â»â¶. The reliability safety factor n is 7:2, or 21.25. Based on these calculations, the design and material selection for the injector pressure regulating spring are deemed reliable.
The flow area negatively affects the dynamic sealing performance of hydrodynamic valves. Therefore, the valve lift and sealing hydraulic power tend to cause the valve to close, making it essential to properly match the taper angle to ensure good dynamic characteristics. These factors influence the dynamic response time. At the same time, rapid discharge is achieved alongside the hydraulic power. The size of the valve is influenced by various elements, such as the valve core structure, the overcurrent area, and the input voltage, which should be appropriately increased while reducing the winding windings efficiently.
Curved Spring Washers,Bowed Spring Washers,Stainless Steel Curved Washers
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