Scrap management in PP module

hi,

i need some help with scrap management issue.

where i can find a documentation of standard sap for scrap material management.(if you can send me link it will be a huge help).

when I add new operation for scrap in C202 tcode and perform process order with weighing the componets not disposal.

in process order I can see after the first perform mvt 101 with mvt 261 for components and its OK but in the next step when i perform the second step of scrap i get mvt 531 for scrap material in minus and the stock increased in MMBE only for scrap material.

anyone can tell me if this is procedure of perform scrap from process order??i attach screenshot.

regards,

Amit Berku