The Wheelabrator Group has successfully delivered and commissioned a wing-peening system for the XAIC aircraft-manufacturing company, located in X’ian, China. The new MP 20,000 machine will be mainly used for peen forming and saturation strengthening of wing-skin panels of large-sized civil airplanes.


The airblast peening pass-through system is fully programmable and operates automatically to the highest standards of precision, meeting the strict requirements of the latest aerospace specifications. The machine was required to shoot peen chordwise, and provide wing spread direction and sectional bending for wainscot parts in wings. It will also be used for shape correcting and strengthening of aeroplane structural parts, including stringers, spars and flange integral beams.

The installation has a CNC-driven longitudinal monorail conveyor system on which the workpieces are located on a steel gantry with convenient and reliable clamping devices. Single-wing panels or multiple-component arrangements are possible on the gantry within the following maximum workpiece dimensions:

  • 20,000mm (length) x 2,500mm (width)
  • Variable thickness in section, with maximum thickness of 25mm and minimum of 2mm for aluminium alloys, with bi-directional processing

The machine is operated through one GE FANUC CNC system with two operator screen stations and two operator hand-held controls, which provides for easy programming of this nine interpolated multi-axis system. The CNC is programmable in ISO language and has a capability for ‘off-line’ programming.

The XAIC project leader, while signing the final acceptance protocol, commented: "We have all appreciated both the warm welcome extended to us in France and the high level of qualification and professionalism demonstrated by the Wheelabrator Group team for engineering, building and training XAIC engineers on such an advanced peen forming system. This will help increase XAIC production capability and final product quality for building the aircraft of the future."


Sisson Lehmann product technologies from the Wheelabrator Group excel in the development and manufacture of highly accurate and innovative airblast shot peening systems.

The centre of excellence, based in Charleville, France, has completed the MP advanced CNC and / or robotic peen-forming and shot-peening machine programme to address the needs of the worldwide aerospace industry, both for new part manufacture and for maintenance operations.

Representing the latest developments in aerospace peen forming, strengthening and shot peening processes, the new MP range can process the widest variety of aircraft structures and wing skin panels, jet engine parts and landing gears to improve their resistance to fatigue.

Today, several major aerospace companies are operating the most advanced versions of Sisson Lehmann equipment. With over 50 machines in operation, the MP range now includes seven machine models.