In　the　past　decades,　the　theories　of　invariant　moments　have　been　researched　extensively　and　wildly　used　in　many　fields.　However,　for　the　laser-welding　spots　of　titanium　tubes　or　other　fixed　objects,　the　invariant　moments　are　inapplicable.　Besides,　the　studies　and　experiments　about　image　classification　by　means　of　the　original　moment　values　were　barely　proposed.　In　this　paper,　the　method　of　classification　based　on　original　moment　values　is　introduced,　and　an　improved　approach　of　KPCA　(kernel　principal　component　analysis)　in　order　to　reduce　the　inner-class　distance　of　the　qualified　laser-welding　spots　is　also　discussed.　Finally,　experiments　are　carried　out　to　validate　the　classification　ability,　and　results　show　that　the　original　moment　values　are　suited　as　pattern　features　in　classification　of　fixed　objects.　©　(2014)　Trans　Tech　Publications,　Switzerland.