Jacquet Weston Engineering have recently supplied a new Nickel and Electroless Nickel hand line to Goodrich Actuation Systems a major Aerospace manufacturer in Liverpool.
Jacquet Weston Engineering with their 38 years experience of plant manufacture were approached by Goodrich Actuation Systems to replace their old process line, although the physical requirements for the plant were not too demanding, (only 250 litre tanks). Goodrich’s stringent process control requirements called for a particularly complex and encompassing control system.
Jacquet Weston have recently invested in the latest AutoCad Inventor suite 2011, this allowed the complex issues associated with the plant such as the location of multiple pipework runs, wiring and compressed air looms and siting of ancillary equipment to be fully resolved prior to the plant build.
The plant itself was a 19 stage line for Nickel and Electroless Nickel plating and a smaller 4 stage line for Chrome stripping. The process tanks were mounted in a stainless steel frame with polypropylene cladding, all pipework and ancillary equipment were located at the back of the plant to improve plant access for the operators. The plant was pre built and dry run at JWE’s Lambourn factory, then split into sections that would allow it to be moved through the customers factory and process shop. All of the ancillary equipment and wiring remained on the plant sections and were simply coupled together on site reducing the time and disruption incurred by the customer.
Due to the complex nature of the process control required Jacquet Weston turned to its well established supplier of Effluent Plant and Control systems Puretech Environmental Ltd, with whom Jacquet Weston were confident they could meet their customers exacting requirements.
With the process control procedure, Goodrich had a clear aim of reducing the manual intervention to a minimum and automating all Health & Safety sensitive procedures such as the nitric acid cleaning operation. This meant a high level of instrumentation with all the control valves for the air agitation and water supply as well as the solution drain valves being pneumatically actuated. The solution level is monitored in all tanks by mean of a hydrostatic level controller (Mempro type) ensuring a ±1% and generating a 4-20mA output.
A State of the art PLC and HMI
All the sensors and actuators are controlled by mean of a PLC. In order to reduce the amount of wiring, a bus cable is linking four remote Input / Output modules. The entire plant control is at the operator's fingertips by mean of an HMI 10" tactile screen. Operating the Nickel Strike station for example is a simple as switching the station on and setting the required amperage on the screen. The system automatically controls the filtration, water top-up, temperature control, air agitation and rectification.
A significant benefit of such an advance system is that the operator can demonstrate the operational parameters at the time a part was processed. All analogue inputs such as level, temperature, current and voltage are datalogged and accessible at any time by the operator. The automation can also ensure that the operators work within pre-set parameters that can only be modified by authorised personnel and protected by mean of passwords.
Enhanced health and safety
Goodrich considers its health & safety responsibilities to be a priority, one area which has been the focus of attention is the nitric acid cleaning of the Electroless Nickel stainless steel tanks. Two identical process tanks have been supplied, when required, the operator can launch a cleaning cycle that transfers the solution to the stand-by tank, which then becomes the duty tank and then cleans the previous duty tank. The system automatically mixes 70% Nitric acid to prepare an effective cleaning solution which 3 hours later returns the tank to its original condition ready for use when required.
Also the dumping of the solutions is only possible providing the temperature is below a set point and providing there is sufficient room in the storage tank down stream.
Another advantage of the system is the continuous monitoring of the heating operation the PLC continuously monitors that the heaters are effectively providing energy to the tanks, interrupting the electric supply (via a dedicated safety contactor) should it find that is not the case, for example if a heater has been accidentally left outside the tank, thus reducing the potential fire risk.
The completion of this contract further enhances Jacquet Weston’s reputation within the Aerospace industry. Goodrich Actuation Systems join an ever growing list of customers who have benefited from Jacquet Weston’s unrivalled knowledge and experience of plant design with the engineering back up of their established workforce.