热锻热切边工艺与毛刺控制｜Hot Trimming: Temperature, Clearance and Burr Control

摘要：热切边在锻件仍处高温时切除飞边，切边温度与凸凹模间隙是两个核心参数。温度过高本体挤压变形，过低则撕裂出毛刺；间隙过小模具磨损快，过大残留厚毛刺。
Abstract: Hot trimming removes flash while the forging is still hot. Trimming temperature and punch-to-die clearance are the two parameters that matter: too hot and the part deforms, too cold and the flash tears instead of shearing.

正文： 锻件终锻完成带有一圈飞边，热切边就是在锻件尚处于高温状态下切除飞边。
Main text: A finished forging leaves the die with a ring of flash around it. Hot trimming cuts that flash away while the part is still at temperature.

一、三个核心参数
1. Three parameters

1、切边温度：温度太高锻件本体容易被切边挤压变形；温度过低材料变硬，切边撕裂，产生毛刺。要在合适温度区间完成热切边。
1) Trimming temperature. Too hot and the trim die squeezes the part body out of shape; too cold and the material hardens, the flash tears rather than shears, and burrs appear. Trim inside a defined temperature window.

2、切边模间隙：凸模凹模间隙是核心；间隙太小模具磨损快；间隙过大，会残留很大毛刺。间隙根据锻件材质厚度确定。
2) Punch-to-die clearance. Too tight and the die wears quickly; too loose and a heavy burr is left behind. Clearance is set from the material and the flash thickness.

3、定位：锻件定位要准确，如果偏位，会切伤锻件本体。
3) Location. The forging has to sit in the trim die accurately. Any offset cuts into the part body itself.

二、四类常见缺陷
2. Four defects and their causes

• 切边撕裂：温度偏低或者间隙不合理，飞边不是剪断而是撕裂，锻件边缘出现撕裂缺陷；
  Torn edge. Temperature too low or clearance wrong: the flash tears instead of shearing and the part edge is torn.
• 锻件本体压变形：切边温度过高，锻件强度低，挤压变形；
  Body deformation. Trimming too hot, when the forging has little strength and yields under the trim die.
• 残留毛刺过大：模具间隙过大，或者模具刃口磨损崩口；
  Excess burr. Clearance too large, or the cutting edge is worn or chipped.
• 切伤锻件本体：工件定位偏移。
  Cut into the body. The part was located off-centre.

三、工艺管控
3. Control

首件检查切边质量；监控锻件切边温度；刃口磨损后及时修模。
Inspect the first piece, monitor trimming temperature through the run, and resharpen the edge as soon as wear appears.

小结 热切边重点管控锻件温度、模具刃口间隙、工件定位；刃口磨损必须及时修复，防止批量毛刺撕裂缺陷。
In short. Hot trimming is controlled by three things: part temperature, edge clearance and location. Repair edge wear promptly, or a burr-and-tear problem runs through the whole batch.