fix: not able to save bom
diff --git a/erpnext/manufacturing/doctype/bom/bom.py b/erpnext/manufacturing/doctype/bom/bom.py
index 2ab1b98..8888a96 100644
--- a/erpnext/manufacturing/doctype/bom/bom.py
+++ b/erpnext/manufacturing/doctype/bom/bom.py
@@ -76,6 +76,7 @@
 		self.set_routing_operations()
 		self.validate_operations()
 		self.calculate_cost()
+		self.update_stock_qty()
 		self.update_cost(update_parent=False, from_child_bom=True, save=False)
 
 	def get_context(self, context):
@@ -84,8 +85,6 @@
 	def on_update(self):
 		frappe.cache().hdel('bom_children', self.name)
 		self.check_recursion()
-		self.update_stock_qty()
-		self.update_exploded_items()
 
 	def on_submit(self):
 		self.manage_default_bom()
@@ -237,7 +236,8 @@
 			self.calculate_cost()
 		if save:
 			self.db_update()
-		self.update_exploded_items()
+
+		self.update_exploded_items(save=save)
 
 		# update parent BOMs
 		if self.total_cost != existing_bom_cost and update_parent:
@@ -318,8 +318,6 @@
 				m.uom = m.stock_uom
 				m.qty = m.stock_qty
 
-			m.db_update()
-
 	def validate_uom_is_interger(self):
 		from erpnext.utilities.transaction_base import validate_uom_is_integer
 		validate_uom_is_integer(self, "uom", "qty", "BOM Item")
@@ -372,15 +370,6 @@
 		if raise_exception:
 			frappe.throw(_("BOM recursion: {0} cannot be parent or child of {1}").format(self.name, self.name))
 
-	def update_cost_and_exploded_items(self, bom_list=[]):
-		bom_list = self.traverse_tree(bom_list)
-		for bom in bom_list:
-			bom_obj = frappe.get_doc("BOM", bom)
-			bom_obj.check_recursion(bom_list=bom_list)
-			bom_obj.update_exploded_items()
-
-		return bom_list
-
 	def traverse_tree(self, bom_list=None):
 		def _get_children(bom_no):
 			children = frappe.cache().hget('bom_children', bom_no)
@@ -472,10 +461,10 @@
 			d.rate = rate
 			d.amount = (d.stock_qty or d.qty) * rate
 
-	def update_exploded_items(self):
+	def update_exploded_items(self, save=True):
 		""" Update Flat BOM, following will be correct data"""
 		self.get_exploded_items()
-		self.add_exploded_items()
+		self.add_exploded_items(save=save)
 
 	def get_exploded_items(self):
 		""" Get all raw materials including items from child bom"""
@@ -544,11 +533,13 @@
 				'sourced_by_supplier': d.get('sourced_by_supplier', 0)
 			}))
 
-	def add_exploded_items(self):
+	def add_exploded_items(self, save=True):
 		"Add items to Flat BOM table"
-		frappe.db.sql("""delete from `tabBOM Explosion Item` where parent=%s""", self.name)
 		self.set('exploded_items', [])
 
+		if save:
+			frappe.db.sql("""delete from `tabBOM Explosion Item` where parent=%s""", self.name)
+
 		for d in sorted(self.cur_exploded_items, key=itemgetter(0)):
 			ch = self.append('exploded_items', {})
 			for i in self.cur_exploded_items[d].keys():
@@ -556,7 +547,9 @@
 			ch.amount = flt(ch.stock_qty) * flt(ch.rate)
 			ch.qty_consumed_per_unit = flt(ch.stock_qty) / flt(self.quantity)
 			ch.docstatus = self.docstatus
-			ch.db_insert()
+
+			if save:
+				ch.db_insert()
 
 	def validate_bom_links(self):
 		if not self.is_active: