diff --git a/sf_manufacturing/models/stock.py b/sf_manufacturing/models/stock.py
index 5c75bc4d..245c1b11 100644
--- a/sf_manufacturing/models/stock.py
+++ b/sf_manufacturing/models/stock.py
@@ -314,11 +314,13 @@ class StockRule(models.Model):
                                    production_item.product_id.product_model_type_id.id)]
                     product_routing_workcenter = self.env[model].search(domain, order='sequence asc')
                     if production_item.production_type == '自动化产线加工':
-                        for k in (production_item.product_id.model_processing_panel.split(',')):
-                            for route in product_routing_workcenter:
-                                i += 1
-                                technology_design_values.append(
-                                    self.env['sf.technology.design'].json_technology_design_str(k, route, i, False))
+                        for k in ((production_item.product_id.model_processing_panel  or "").split(',')):
+                            if k.strip():
+                                for route in product_routing_workcenter:
+                                    i += 1
+                                    technology_design_values.append(
+                                        self.env['sf.technology.design'].json_technology_design_str(k, route, i, False))
+
                     elif production_item.production_type == '人工线下加工':
                         for route in product_routing_workcenter:
                             i += 1