When choosing a single column straightening machine, it is important to match the three core parameters of the workpiece: material, specifications, and bending degree. Firstly, the material should be considered. For low carbon steel (such as Q235) workpieces, a conventional hydraulic single column machine can be selected, and the straightening force is calculated as "σ s × A × 1.2" (σ s is the yield strength, A is the cross-sectional area of the workpiece, and 1.2 is the safety factor). For high-strength alloys (such as 40CrNiMoA), a servo driven model should be used, and the indenter should be replaced with a hard alloy material (HRC ≥ 60); Next, look at the specifications. When the length of the workpiece exceeds 3m, it is necessary to choose a machine model with auxiliary support rollers (the distance between the support rollers can be adjusted within the range of 500-1500mm). For coarse shaft workpieces with a diameter exceeding 100mm, a reinforced main oil cylinder (rated pressure ≥ 31.5MPa) should be equipped; Finally, consider the degree of bending. For workpieces with a bending amount exceeding 5mm/m, a multi pass straightening machine should be selected (3-5 straightening stations can be set), while for micro bending workpieces (bending amount ≤ 0.5mm/m), a high-precision machine (straightness detection accuracy ≤ 0.01mm/m) should be selected.

When selecting, three major misconceptions should be avoided: firstly, focusing only on the maximum straightening force and neglecting the stroke. For example, for shaft type workpieces with a straightening length of 2m, if the maximum stroke of the machine model is only 300mm, the workpiece needs to be moved multiple times, which can easily lead to repeated errors; The second is to ignore the clamping method of the workpiece. If the slender shaft workpiece is clamped at both ends, it is easy to produce additional bending. Therefore, a clamping mechanism with central support and two end positioning should be selected; Thirdly, the follow-up automation docking has not been considered. If the production line needs to achieve automatic loading and unloading, a model with PLC interface needs to be selected for linkage with the robotic arm and conveyor belt. A certain agricultural machinery manufacturing factory once used a single column machine with insufficient stroke, resulting in a 40% decrease in the straightening efficiency of the tractor half shaft. It was only after replacing the large stroke machine model that normal production resumed.