When parts are prepared for welding, their edges can be beveled to produce a groove for the weld. You can define the angle of bevels and grooves.
You can either prepare a part for welding manually, or apply a component that does it automatically, or you can use the Preparation options in the Weld properties or in the component weld properties.
Note: When you use components' weld preparation options, the supported weld types are placed correctly in the model. If you use cuts for preparing the part edges, the welds may not be placed correctly.