diff --git a/hb_server/apps/mtm/models.py b/hb_server/apps/mtm/models.py
index 7815711..b7b99c2 100644
--- a/hb_server/apps/mtm/models.py
+++ b/hb_server/apps/mtm/models.py
@@ -39,7 +39,8 @@ class Material(CommonAModel):
     type = models.PositiveSmallIntegerField('物料类型', choices= type_choices, default=1)
     sort_str = models.CharField('排序字符', max_length=100, null=True, blank=True)
     unit = models.CharField('基准计量单位', choices=unit_choices, default='块', max_length=10)
-    count = models.IntegerField('物料总数', default=0)
+    count = models.PositiveIntegerField('物料库存总数', default=0)
+    count_safe = models.PositiveIntegerField('安全库存总数', null=True, blank=True)
     piece_count = models.PositiveSmallIntegerField('单片玻璃数量', null=True, blank=True)
     class Meta:
         verbose_name = '物料表'
diff --git a/hb_server/apps/sam/filters.py b/hb_server/apps/sam/filters.py
new file mode 100644
index 0000000..e69de29
diff --git a/hb_server/apps/wpm/views.py b/hb_server/apps/wpm/views.py
index 09d144d..d0e0986 100644
--- a/hb_server/apps/wpm/views.py
+++ b/hb_server/apps/wpm/views.py
@@ -563,7 +563,7 @@ class OperationViewSet(ListModelMixin, RetrieveModelMixin, CreateModelMixin, Upd
         omos = OperationMaterial.objects.filter(operation=op, 
                 type=SubprodctionMaterial.SUB_MA_TYPE_OUT)
         sps_omo_l = omos.filter(use_scrap=False).values_list('subproduction_plan', flat=True)
-        if set(list(sps_omi_l)) == set(list(sps_omo_l)):
+        if set(list(sps_omi_l)) == set(list(sps_omo_l)) or op.step.type == Step.STEP_TYPE_COMB:
             pass
         else:
             raise exceptions.APIException('消耗与产出不一致')