Delavan 6.50GPH, 60B (7) nozzle

This is a Delavan oil nozzle, catalogue article 345.892.120, also referenced as 00650-60B7 and 3042222. It belongs to the category of oil nozzles, which are precision consumable parts used in pressure-jet oil burners. An oil nozzle of this type atomises fuel oil into a fine spray so that it mixes with combustion air and burns completely. The nozzle is mounted in the burner’s blast tube, downstream of the oil pump and solenoid valve. Its three key parameters – flow rate (in US GPH at 100 psi reference pressure), spray angle (typically 30 to 80 degrees), and spray pattern (hollow cone, solid cone, or semi-solid cone) – together determine the shape and position of the flame within the combustion head. The thread is standard for this class of component. When selecting a replacement nozzle, all three parameters must match the burner manufacturer’s specification on the data plate. Using the correct flow rate but an incorrect spray angle or pattern can cause sooting, pulsating combustion, or unstable ignition. Because the nozzle is a consumable part, it is good practice to replace it during annual maintenance, and to use only the type specified for the burner model. Nozzles of this brand are commonly encountered in commercial and industrial oil-fired heating equipment.