diff --git a/sf_manufacturing/models/sf_technology_design.py b/sf_manufacturing/models/sf_technology_design.py
index 7b79d485..c3006a94 100644
--- a/sf_manufacturing/models/sf_technology_design.py
+++ b/sf_manufacturing/models/sf_technology_design.py
@@ -39,7 +39,10 @@ class sf_technology_design(models.Model):
         if 'active' in vals:
             if self.production_id:
                 process_parameters_id = self.production_id.technology_design_ids.mapped('process_parameters_id')
-                self.production_id.product_id.model_process_parameters_ids = process_parameters_id.ids
+                if process_parameters_id.ids:
+                    self.production_id.product_id.model_process_parameters_ids = process_parameters_id.ids
+                else:
+                    self.production_id.product_id.model_process_parameters_ids = None
         return res
 
     def unlink_technology_design(self):