Commercial Aircraft Wingbox Autoclave in China

Illustration notice. Process illustrations are not verified photographs of this installation.

Project reference basis. Figures and configuration details are reported in the supplied project brief. They are reference values for the stated application, rather than verified acceptance results or a guarantee for another installation. Confirm the source records, material, tooling, operating schedule and test method when assessing a comparable project.

Project configuration and outcomes described in the supplied project brief.

A premier commercial aviation composite aerostructures group in Shaanxi deployed Haifeng’s aerospace-grade intelligent composite autoclave system. The project was commissioned to establish a primary aerostructure manufacturing cell for 11.2-meter one-piece carbon fiber wingbox covers and integrated stringer stiffened skins for commercial passenger jetliners.

Prior to this installation, the facility was restricted by undersized 8-meter autoclaves, forcing engineers to manufacture large wing covers in multi-piece segments joined by metallic splice plates. This added 85 kg of parasitic fastener weight per aircraft and introduced structural stress risers. Furthermore, temperature gradients (±4.5°C) across older vessels triggered thermal runaway exotherms in 38 mm thick stringer nodes, producing internal void contents between 0.8% and 1.2% that repeatedly failed civil airworthiness non-destructive testing.

Haifeng engineered a complete turnkey autoclave manufacturing cell centered on the HF-ACV35-AERO system (Ø 3.5 m× 12 m working envelope). Featuring symmetrical convective heating holding zone temperatures within ±1.5°C and 48 independent vacuum telemetry channels, the supplied brief describes monolithic 11.2-meter wingbox panels with reported laminate porosity below 0.2%; this is not a zero-porosity claim or proof of flight qualification.

Concept illustration: Generated concept illustration for process discussion; not a photograph of the specified machine, a customer facility or a delivered project.

Configuration reported in the supplied brief.

Haifeng engineered an autoclave curing cell for the described aerostructure configuration. Large carbon fiber prepreg layups placed on Invar 36 wingbox tools are enveloped in vacuum bags and loaded via automated motorized rail beds into the autoclave chamber.

The vessel door closes under hydraulic breech-lock safety mechanisms. High-purity nitrogen gas pressurizes the vessel to 1.0 MPa, applying uniform hydrostatic consolidation force across the 11.2-meter tool face. Symmetrical full-length air ducts driven by heavy water-cooled circulation blowers circulate hot nitrogen gas at 3.0 m/s, heating the chamber at a strict 1.5°C/min ramp to 180°C.

Multi-loop PID algorithms monitor 48 part-mounted thermocouples, ensuring temperature differentials across thin skin regions and 38 mm thick stringer nodes stay strictly within ±1.5°C. Following an isothermal dwell of 120 minutes at 180°C, high-capacity closed-loop heat exchangers ramp cooling at 1.8°C/min to room temperature. The supplied brief reports a 100% ultrasonic inspection pass rate for its inspected wingbox population and a laminate porosity figure below 0.18%. Inspection coverage, defect acceptance and quantitative porosity use distinct measurement and acceptance records.