Emerging Subsea Networks

Transcription

1 3D PRINTING SUBMERGED EQUIPMENT Adrian Jarvis (Huawei Marine Networks Co., Limited) Huawei Marine Networks, Co., Limited, c/o Global Marine Systems Ltd, Winsford Way, Chelmsford, CM2 5PD, UK Abstract: Similar to the impact of fibre optics over copper in telecommunications, back in the 1980 s, 3D printing is providing a revolutionary step change in manufacturing technology. It is beginning to have major influences on how parts, structures and equipment are made, allowing engineers to imagine the impossible and create products previously impossible to build using traditional methods. 3D printing is being used across many Hi-Rel/Hi- Performance industries and disciplines that demand quality, reliability and repeatability commensurate with that expected within subsea telecommunication equipment. This paper will discuss the key design and manufacturing considerations, of both metallic and nonmetallic 3D printing and will consider the question: Is a 3D printed Repeater possible? 1. INTRODUCTION TO 3D PRINTING 3D printing is a process for making a physical object from a three-dimensional digital model. It can be made from any material, usually through an Additive Manufacturing (AM) process. This is different from traditional machining methods that remove material from a solid. 2. HISTORY AND DEVELOPMENT OF 3D PRINTING 3D printing has existed for many years in various forms. In the past, it was often specialist modelling companies or rapid prototyping bureaus that would produce prototypes, however in the mid to late 1980 s True 3D printing appeared [1]. The first patent for Stereo Lithography Apparatus (SLA) was granted in the mid 80 s, leading to the formation of 3D Systems. Around the same time, Selective Laser Sintering/Melting (SLS/M) was patented. By the beginning of the 90 s, Stratasys Inc. had patented Fused Deposition Modelling (FDM). These companies along with others, such as EOS and Renishaw, remain the dominant suppliers within the AM arena. By the mid 2000 s, the desire for accessible, cost effective office based printers grew. Companies, such as Makerbot and RepRap, created basic desktop printers that were available at an entry level of around 500 in comparison to 0.5M+ for an industrial SLM. It is estimated the global value of 3D printing in 2013 was around $3 billion and may rise to an estimated $21 billion [2] in D PRINTING TECHNOLOGIES AND MATERIALS The three most widely used printing methods for Additive Manufacture are SLA, FDM and SLS/M. SLA uses a photosensitive resin (such as epoxy) to create parts. Typically UV lasers are used to draw the item in a container of resin taking geometrical data from a 3D CAD model file. The activated resin Copyright SubOptic2016 Page 1 of 10

2 solidifies into the desired shape. Typically this process uses a movable bed that either gradually submerges into or withdraws from a resin tank. The object is drawn a layer at a time until the item is created. SLA can make complex, high resolution, fully functional parts, and is typically used for prototyping or as mould templates. FDM uses filaments of polymers, such as polycarbonate, nylon or even materials, such as clay, chocolate, and recently glass. Filaments are delivered through motorised drives to a heated movable extruder/head. This softens or melts the material into a fine strand that is deposited on to a movable bed and fuses to the layer below. A combination of build, and where provided, support material (required to provide structural support for voids or overhangs) is usually used. The resolution of the build is controlled by the head aperture size, material properties, etc. SLS/M is best suited to materials, such as titanium, stainless steel, aluminium and ceramics. This process uses powdered material that is evenly spread over a moveable bed. A laser (or electron beam in the case of Electron Beam Sintering) is used to fuse or sinter the powder to the layer below. Unfused powder acts as support material for voids and overhangs. The quality and resolution of this build is determined by material particle size and capabilities of the machine. 4. DISADVANTAGE OF 3D PRINTING 3D printing is an emerging technology that is beginning to encroach on traditional manufacturing processes. Simple mass produced parts designed with machining, casting, moulding, etc. in mind, could be 3D printed, however, this is not always desirable. For example: 3D printing for high volume, simple components is not cost effective. 3D printing is not a substitute for design for manufacture. Equipment is expensive and energy hungry (typically 50+% more electrical energy than injection moulding [3] ). Quality and detail of data files critical to successful printing, rubbish in, rubbish out. Material costs are high when compared to standard stock material, availability often limited. Material properties are typically different to conventional materials, often resulting in reduced density, fatigue, strength and increased porosity. Printed parts mechanical performance not homogenous, particularly in the build direction. Parts can warp and distort on cooling. Finish is limited to the quality and resolution of the process and material. Post processing usually required. Legal ownership [4] on IP and piracy/copyright is unclear. Ownership of liability as a result of part failure is vague. Copyright SubOptic2016 Page 2 of 10

3 5. ADVANTAGE OF 3D PRINTING Below are some of the key advantages of 3D printing: Design of complex, one-off (or short production run, typically <250), components are very cost effective. Manufacture of parts which are not possible to make using traditional methods, including matrix structures, complex blends and surfaces. 6. CREATING AND DESIGN FOR 3D PRINTING A typical workflow to produce a piece of tooling, using an industrial FDM 3D printer, is detailed below. Having first created or converted a file into a 3D CAD model (see Figure 1) and saved it as a STL (Stereo Lithography) date file, it is then loaded into 3D printer software for conversion (see Figure 2). 3D scanned parts can be reverse engineered. Time critical component manufacture with rapid design iteration can reduce front end development time. 3d printing can eliminate part tooling, such as mould cores. Figure 1: 3D CAD model. Rapid repair, change out and implementation of production tooling to improve process time and efficiency. Complex assemblies can be printed ready assembled. Material efficiency is high, using only what is required to make the part. Remote, strategic manufacture possible, improving supply logistics and reducing inventory. Figure 2: 3D model showing build and support layers sliced ready for printing. By adopting efficient building techniques, such as: Calibrate and set-up printer correctly. Ensure the design is to the printer resolution and its capabilities. Copyright SubOptic2016 Page 3 of 10

4 Reduce/avoid the use of support material and structures. Orientate to avoiding overhangs, thin sections and ensure holes are created correctly. Consider the material properties in relation to the application. Plan builds to improve efficiency and reduce build time. It is possible to build such an operational part in 10.5 hrs. The Red Bull F1 team, include a 3D printer [5] as part of their track-side mobile workshop. An example of reverse engineering comes from Impossible Creations who recreated the Britannia-upon-Globe Mascot [6] for a restoration project on a Rolls Royce RF14. Using an existing sculpture, a 3D scan was performed to create a CAD model from which a 3D printed master mould was made. The final mascot was cast in brass and nickel plated. Figure 4: 3D Printed Master Mould (Left) used to create the Brass Casting (Right) Figure 3: Finished part 7. CURRENT APPLICATIONS 3D PRINTING 3D printing has many applications. From medical uses, such as tooth implants, prosthetics and replacement joints in both the human and animal world, to toys, art and sculptures, and even wearable clothing and jewellery. From an engineering perspective, motor racing has long benefited from 3D printing. F1 uses 3D printing to rapidly prototype designs and models for aerodynamic testing, reducing expensive development times. The Bloodhound Super Sonic Car (SSC) will have a 3D printed titanium steering wheel [7] and nose tip when it attempts its world record challenge in Figure 5: Bloodhound SSC Steering Wheel Within Aerospace, Stratasys [8] claims the Airbus A350XWB contains over D printed parts. Airbus said parts weighed 30 to 55% less, while reducing raw material used by 90%. Stratasys used an aerospace certified Ultem resin to achieve this. Copyright SubOptic2016 Page 4 of 10

5 Hi Rel industries comparable with Subsea telecoms, such as space, are pushing 3D printing to the limit. NASA has developed, manufactured and test fired a 3D printed rocket nozzle [9]. Figure 6: NASA rocket nozzle test fire Notably in 2015, NASA astronauts aboard the International Space Station used a 3D printer made by Made In Space Inc. in zero G to create simple parts and tools [10]. Figure 7: 3D printed space wrench NASA s aim is to send files where they are required to print tools, components, etc. to improve operational mobilisation. 8. FUTURE DEVELOPMENTS 3D PRINTING 3D printing is maturing as a technology, but still has much to deliver. As the technology improves with each iteration, so the speed of builds increases, more materials become available and the quality of parts approach that of traditional methods. Along with machine and material developments, other future areas of interest affect logistics and engineering design. Solidworks CAD software currently provides users access to 3D content library featuring models of parts from suppliers or users for download. These can be converted into printer files, but usually detail or resolution is limited. Catalogues of downloadable items do currently exist, but tend to be end user limited. The next evolution would see 3D printer friendly formats [11] of parts readily available for use, with or without access to CAD software. This is an area where suppliers and manufacturers are looking to develop. The ability to send data files to manufacturing facilities anywhere in the world for 3D printing is a powerful tool. Strategic positioning of printers allow for a dynamic response to demand and customisation. Logistic support is simplified as bulk material rather than finished goods can be transported more efficiently. Inventory is reduced as finished goods are created on demand simplifying stock control. Such an approach has significant potential to a telecoms system provider with a global manufacturing foot print. Some of the most exciting developments are in CAD software itself. Developers are starting to utilise FEA to create iterative goal driven optimisation generated designs [12]. Here the component is automatically optimised for properties like strength or weight by growing the part through several iterations, producing complex functional geometries. Creating useful electrical circuits and electronic components is an area 3D printing technology has yet to conquer, including optical components, even though Massachusetts Institute of Technology (MIT) recently developed a method to 3D print glass [13]. However, the use of conductive polymers and inkjet Copyright SubOptic2016 Page 5 of 10

6 technologies has resulted in the creation of simple circuits [14]. Significant work still needs to be undertaken in this area to evaluate the long term reliability of such complex hybrid structures. In the short term, improving the performance of the current technologies is where major benefits would be most felt. Improving build speed, increasing material type and availability, using multiple heads and materials simultaneously are a few areas under development. As markets expand and availability grows, the price of materials will reduce and 3D printing will become more competitive. 9. 3D PRINTING IN SUBMERGED EQUIPMENT New Submarine Repeater manufacturers, such as HMN, are now operating 3D printers for prototyping, tooling and manufacture. produced to provide a dimensionally accurate model on which to trial fibre routes, evaluate HV clearances, mechanical interfaces and potential clashes. Initial testing showed modifications were required to be made to the source CAD model and as such the part was re-made overnight ready for further iterative analysis. In order to HV test the design, the final iteration was printed using SLA, as the porous nature of the FDM build would not support the test parameters. On successful completion of functional testing, the completed part data was sent via for manufacture into an operational moulded part. Complex fibre routing can be a challenge, but here 3D printing helped remove this issue and allowed the creation of compound curve channels that could not be easily produced by normal means. Figure 9: Fibre Tray Iterations (from the left) FDM, SLA and final moulded part Figure 8: Prototype cable integration parts on a Stratasys Fortus 360MC Printer A number of wet plant case studies are considered: Case Study #1: Fibre Tray An example of its use was in the form, fit and function analysis of a hybrid fibre storage tray and High Voltage (HV) insulator. A 3D FDM printed part was Case Study #2: Bend Limiter Design When developing ideas, it is useful to have access to a physical model to ensure principles developed in the design phase work as intended. A Repeater Bend Limiter is a complex assembly that is required to articulate to specific parameters whilst transferring cable load. To commit a load bearing assembly to manufacture can be dangerous and costly if errors exist. A partial scale model of the assembly was 3D printed before cutting metal. The model was used to test the dynamic performance, such as bend angles and ease of articulation. Within 3 iterations involving Copyright SubOptic2016 Page 6 of 10

7 some minor modifications, final parts were made, assembled and tested to 60 tons tension. Risk was reduced and the design committed to operational use with confidence. models were used to 3D print wax mould cores. These were covered in ceramic slurry and fired to create a mould for investment casting into which the metal was poured as shown in Figure 11. Such high accuracy casting techniques require minimal machining. Case Study #4: 3D Printed Tooling Where 3D printing is particularly powerful is in the manufacture of production tooling. Figure 10: This initial 3D prototype evolved in to this assembly. Case Study #3: Cast Bend Limiters In order to cost reduce complex geometries within the Bend Limiter, part casting was considered as an alternative to traditional machining process. To perform complex bends on a sheathed insulated metal tube, it was necessary to develop non-invasive soft tooling so as not to impact HV performance. The geometry of the formed tube could not be completed using a single tool or process. A number of jigs were developed and iteratively tested for each stage of the manufacturing process, rapidly reducing the time to release production equipment to the manufacturing facility in China. Figure 12: Tube bending using 3D printed pipe bending jig. Figure 11: Cast parts made from 3D printed mould. Here 3D printing was effective in providing tooling to aid the process. CAD In summary, 3D printing has shown to be a valuable and essential tool during prototype and manufacture. As the initial prototype develops, so the tooling evolves.3d printing allows tooling to be rapidly updated reducing turnaround times from weeks to hours. Copyright SubOptic2016 Page 7 of 10

8 simplify designs, create features not readily manufacturable by standard means and improve build efficiency using materials varying from metal or plastic depending on operational requirements. Figure 13: 3D printed jig applies bends to tube. The ability to send CAD or model data to suppliers, or directly to machines across the world, provides a useful dynamic response and flexibility. For example, when a change or development is made in the UK, the necessary parts can be sent for manufacture at any strategic location in the world or anywhere that has the necessary 3D printer. For example, equip a cable ship with 3D printers and it then becomes possible to repair cables using jointing parts manufactured on board, providing a truly rapid response with little inventory requirements. The use of Product Data Management (PDM) systems are critical to ensure issue sensitive data, such as part files, are maintained and controlled. Inspection of parts is necessary to ensure compliance through the use of calibrated reference builds or coupons that can be remotely verified. Figure 14: Completed tube. Once developed the tooling is simple to transfer to manufacturing and if broken easily replaced. The ability to turnaround prototypes and tooling changes within hours has resulted in a conservative saving of 9 months in development time SO WHERE NEXT? 3D printing has allowed repeater manufacturers, such as HMN, to create parts and assemblies by merging components (thus reducing inventory), 10. CONCLUSIONS To answer the question: Is 3D printing of submerged equipment possible? The answer is: Yes.up to a point. The technology is now sufficiently robust that many of the metal and plastic internal and external mechanical parts of a repeater could be 3D printed. However, hybrid builds using optical and electrical components have a long way to progress before they could be realistically printed. Is it desired to 3D print submerged equipment? From a cost prospective, traditional manufacturing methods are still Copyright SubOptic2016 Page 8 of 10

9 the best solution for the majority of volume product. The current benefit is still in product development and tooling design, allowing for rapid development cycles, exploration and validation of multiple ideas, and providing production tooling quickly both locally and remotely. Manufacturers have only just begun to see the potential and within the next 10 years, as the technology develops and costs reduce; 3D printing could emerge as the dominant manufacturing process. 11. REFERENCES [1] 3D Printing Industry, 3D Printing History in 3D Printing Guide, Ch. 2, 2014, February 12, [Online]. [3] K. Kovac, How Green is 3D Printing?, 2013, December 2, [Online] [4] G. Coraggio, Top 3 legal issues of 3D Printing!, 2015, September 7, [Online]. 15/09/top-3-legal-issues-of-3d-printing [5] Renault Truck, Seven Renault Trucks T For Red Bull, 2015, June 30, [Online]. [2] L. Columbus, Roundup of 3D Printing Market Forecasts and Estimates, 2014, August 9, [Online]. s/2015/03/31/2015-roundup-of-3dprinting-market-forecasts-and-estimates/ [6] Britannia-upon-Globe Mascot, TCT Magazine, pp. 34, October 2015 [7] J. Amos, 3D Printed Tech To Steer Bloodhound Super-Sonic Car, 2015, September 23, [Online]. [8] K. Krassenstein, New Airbus A350 XWB Aircraft Contains Over D Printed Parts, 2015, May 6, [Online]. 3d-print [9] J. Cunningham, You re Fired!, Engineering Materials Magazine (A Eureka Publication), pp , Winter 2013 [10] NASA, Space Station 3-D Printer Builds Ratchet Wrench To Complete First Phase Of Operations, 2014, December 22, [Online]. n/research/news/3dratchet_wrench [11] J. Vanderkay, 3MF Consortium Launches To Advance 3D Printing Technology, 2015, April 30, [Online]. [12] T. Abbey, An Optimization Overview, 2012, December 1, [Online]. Copyright SubOptic2016 Page 9 of 10

10 [13] J. Webb, Sewing With Molten Glass And Maths, 2016, January 1, [Online]. [14] R. Merritt, 3D Printers Spit Out Small PCB s, 2015, November 22, [Online]. c_id= ACKNOWLEDGEMENTS The author would like to express his gratitude to Ian Watson at Huawei Marine Networks Co., Limited. Copyright SubOptic2016 Page 10 of 10