//oncreate olayına yazılacak
procedure TForm1.FormCreate(Sender: TObject);
var
l: DWORD;
begin
l := GetWindowLong(Self.Handle, GWL_STYLE);
l := l and not (WS_MINIMIZEBOX);
l := l and not (WS_MAXIMIZEBOX);
l := SetWindowLong(Self.Handle, GWL_STYLE, l);
end;