... and Heat-Exchanger 2. Alloy tubes 3.surface treatment:oiled, varnish,passivation etc. APPLICATION:For Boiler,Superheater and Heat-Exchanger.Production ... Dimension Test,Non-destructive Test,Hydrostatic Test.Surface treatmentOil-dip,varnish,Passivation,Phosphating,Shot BlastingSize RangeO.D 19.05-101.6mmW ...