在工程机械结构件的生产中，经常需制造各种尺寸的U形弯曲件，通常的做法是制造V形或U形压模。V形压模的优点在于通用性好，缺点是不能保证准确的弯曲尺寸，而且由于受凸模宽度所限，也不能压制深宽比过大的U形弯曲件。因此，对于弯曲尺寸要求较高或深宽比较大的U形弯曲件大多 In the production of construction machinery structures, it is often necessary to make U-shaped bent parts of various sizes, and it is common practice to make V-shaped or U-shaped stampers. V-shaped stamper has the advantage of good versatility, the disadvantage is that it can not guarantee accurate bending size, and due to the width of the punch limited, it can not suppress the aspect ratio U-shaped curved pieces too large. Therefore, the bending of the higher requirements for the size or larger U-shaped curved part of the majority