Peening machines deform and strengthen a metal surface by hammering the surface with small beads, shot peen balls or peening media. These machines perform peening or burnishing functions to the surface of media such as metal shots or other smooth, round-shaped media. Shafts and turbine blades may be shot blasted, as peening improves the fatigue strength of metallic materials by imparting a residual compressive stress on the parts.
Peening machines may use a CNC controller to operation automatically with little-to-no operator intervention. Machines may also be system controlled through a PC interface.
Most Common Peening Machines
The most common peening machines are blast or jet pressure machines or abrasive grain machines. With blast or jet pressure peening machines rely on water or air to create a blast stream for cutting or propelling abrasive particles. Abrasive grain peening machines are set to a particular rate or flow for the distribution of abrasive gain in the system. Peening machines may use different types of abrasive feed options, including wet or dry, gravity, pressure, or suction / venturi.
In addition to feed options, other considerations for peening machines include the system or component type. Options commonly include blast cabinet or enclosure types, blast rooms, dust collection or filtration system, gun / lance, and media separator. Blast cabinets or enclosures typically consist of a chamber with glove ports, a viewing window, and internal lighting. When using this type of peening machine, the workpieces rest of an open grid that allows used abrasive to drop through for recycling purposes.
Blast room or cutting booth peening machines are commonly composed of a room with internal lighting that holds the workpiece and the operator. The operator may hold the blasting nozzle on the end of a lance. Dust collection peening machines remove fine particle sizes of abrasives, media and blasting waste that would otherwise become suspended in the air.
Gun / lance and media separator options are also available as peening machines. Guns or lances direct a stream of abrasives and carrier fluid or water through a nozzle at the appropriate part of the workpiece. Media separators, or reclaimers, are used in blast machines to remove undersized abrasives, media, or waste.
Other considerations for choosing peening machines include part handling and workpiece loading. Part handling refers to the direction a workpiece travels along a particular axis. Workpiece loading refers to how a piece moves through the peening machine. Common workpiece loading options include handheld options, or the use of belt or roller conveyors, overhead monorail conveyors, gantry or XY table, rotary table, tumbler belt, or a spinner hanger.