Method for connecting rod

A method for reinforcing a nodular cast iron connecting rod, the method comprising:

• determining a weight m1, having units kg, of a standard steel connecting rod;
• preparing the nodular cast iron connecting rod having the same size with the standard steel connecting rod and comprising a first end, a second end and a shank provided between the first end and the second end, a second end and a shank provided between the first end and the second end, wherein the shank of the nodular cast iron connecting rod is provided with a groove;
• determining a weight m2, having units kg, of the nodular cast iron connecting rod;
• simulating to reinforce the shank with a reinforcement material having a weight m, having units kg, through adding the reinforcement material to a bottom of a groove of the nodular cast iron connecting rod to reduce a depth D of the groove;
• calculating a reinforcing thickness H, having units m, for the shank of the nodular cast iron connecting rod according to the following equation:
• H
• =
• K
• ×
• m
• 1
• -
• m
• 2
• p
• ·
• S
• wherein p is a density of the nodular cast iron having units kg/m3;
• S is a cross-sectional area of the groove having units m2;
• and K is a constant of proportionality ranging from 0.9 to 1;
• calculating a size of a reinforced shank;
• manufacturing a reinforced nodular cast iron connecting rod based on the size of the reinforced shank;
• and
• testing and calculating stiffness of the reinforced nodular cast iron connecting rod;
• when the stiffness of the reinforced nodular cast iron connecting rod is less than a preset stiffness, increasing the constant of proportionality K to recalculate the reinforcing thickness H;
• and
• when the stiffness of the reinforced nodular cast iron connecting rod is equal to or larger than the preset stiffness, indicating the stiffness of the reinforced nodular cast iron connecting rod is qualified.