Introducing Zero Defect Manufacturing

Challenge

A challenging market situation, where competitors are R&D intensive, and are increasingly coming from lower cost countries. At the same time, the aerospace industry sets high demands for its suppliers in terms of quality and precision.

Solutions

Total integration of digital solutions and automated robots. With real-time monitoring, defects and faults in production are minimised. 

Costs

GKN Aerospace has invested a considerable amount and time in acquiring and implementing advanced CNC machines, Electrical discharging machines (EDM), special process equipment and process control systems supporting Zero Defect Manufacturing (ZDM). 

Result

Production is more efficient and less labour intensive as the extent of manual work has been reduced. 

Introduction

GKN Aerospace Norway produces components for commercial and military aircraft engines for the world’s leading aircraft original equipment manufacturers (OEMs). In this area, the company is specialised in complex structures and rotating parts.

GKN Aerospace Norway was established in 1976/77. Since 2012, the company has been a part of the international GKN Group that has 56,000 employees in more than 30 countries. 

Pressure on lowering costs and being innovative

Competition within the market segment that GKN Aerospace is in is increasing, and the competition is global. The competitors are typically highly R&D intensive, and some of them are from low cost countries. Due to this increasing market pressure, GKN Aerospace has recognised that they needed to develop their production in terms of lowering costs without compromising the company’s ability to manufacture innovative and high quality products.

At the same time, the aerospace industry makes high demands of its suppliers and sets high requirements in terms of quality. In recent years, the OEMs (the clients of GKN Aerospace) have directed more attention towards optimising the supply chain by 1) focusing on suppliers with full responsibility for the production line (from the design phase to the production), 2) having fewer suppliers and partners and 3) setting requirements for faster time to market.

“We deliver products to an industry with a low tolerance concerning the standardisation of the products, setting extremely high standards to the quality of the components of their suppliers. As a consequence, we have to be up-to-date all the time in our production, or else we will not get new contracts”.

- Ole B. Hoen,
Technical Manager at GKN Aerospace Norway

CNC machining (Computer Numeric Control) is the key component in GKN Aerospace’s production. The machine digitally controls all features of the production, including feed rate, coordination, location and speed in the production processes. It allows high precision in controlling advanced machine tools and peripheral equipment. In addition, it enables the production of complex shapes that would be highly difficult to achieve with manual manufacturing.

Other vital technologies include Electrical discharge machining (EDM). A manufacturing process where a desired shape is obtained by using electrical discharges (sparks). Non-destructive testing (NDT) is also used and is an analysis technique that evaluates the properties of a material, component or system without destroying the part.

GKN Aerospace has worked systematically with integrating digitalisation in its automation processes. According to the Technical Manager Ole B. Hoen, the company has successfully implemented and continue to develop Zero Defect Manufacturing (ZDM), by advanced real-time process control system and mind set focused especially on precision, high-value and high-performance parts as well as custom-designed components. By combining artificial intelligence and sensors, the system seeks to overcome issues related to production defects.

At GKN Aerospace, the system consists of the following elements: Censoring and cognitive signal analysis, Real-time corrections and adaptive control (self-optimising), Artificial intelligence techniques (neural networks and fuzzy logic) for machine system self-adaption, and Data communication, integration and storage. 

How ZDM (Zero Defect Manufacturing) works

The ZDM (Zero Defect Manufacturing) system is designed to automatically monitor the entire factory-floor manufacturing process, from the quality of raw materials entering the production line to variances in tools and processes during each production run. As a closed-loop system, controllers are immediately alerted to any defects, and changes can be made to eliminate the source of the problem. With the system, there is potential to dramatically reduce scrap by detecting production errors instantly and eliminating the propagation of defects along the process stages.

Before the implementation of ZDM, the production line was affected by 1) human subjective influence, 2) varying degree of built-in stress affecting downstream processes, 3) minimal feedback of assembly data, 4) ingoing material with large variance and 5) weld defects during the weld up sequence. The production line has been standardised since the system has been implemented, meaning standard workflows and methods, more uniform stress state, automatic feedback from the production and the ability to handle variance in the ingoing material.

“We use a system that makes it possible to run several hours unmanned production cycle enabling openings in operator shift patterns. This means that without manual supervision, we can still maintain a high level of quality and precision”

- Odd Terje Lium,
Vice President Production at GKN Aerospace Norway

The results: Increased efficiency – but there is room for improvement

A key outcome for GKN Aerospace is that production has become less labour intensive as the extent of manual work has been reduced. At the same time, implementing a complex production facility requires a skilled workforce that is accessible in Norway, but not necessarily in low cost countries. In this way, it safeguards and creates new high-skilled jobs locally.

“We need to have the right competences. We need skills especially within programming, software and administrative solutions. Our location in Kongsberg, Norway is a competitive advantage, because we have access to a skilled workforce”.

- Odd Terje Lium,       
Vice President Production at GKN Aerospace Norway

At GKN Aerospace, there is an awareness that they need to stay ahead all the time. Although they have taken measures to improve their production and raise their level of innovation, new disruptive technologies continue to come in and have the potential to change the global market situation quickly, such as using the possibilities of 3D technology as one example.

 “We have learnt that we are constantly forced to think of the future. We need to think about our processes and the connection between our systems and organisational development. Implementing a new production system is not a guard against the threat from other competitors, and the total effect of our system would be less efficient if we don’t focus on our processes and how to optimise our production”.

- Ole B. Hoen,
Technical Manager at GKN Aerospace Norway