In sheet metal painting for various applications like Tractor, Automobile, most attractive coating is metallic paints and it is widely applied using 3 coats 2 bake or 3 coat 1 bake technology. Both options, results in high energy consumption, higher production throughput time & lower productivity in manufacturing process. During various brainstorming & sustainable initiatives, paint application process was identified for alternative thinking to reduce burden on environment & save energy. Various other industry benchmarking & field performance requirement studies helped us identify the critical to quality parameters. We worked jointly with supplier to develop mono-coat system without compromising the performance & aesthetical properties. This results in achieving better productivity, elimination of two paint layers, substantial reduction in volatile organic content, elimination of one baking cycle and energy saving.
Plastics are prone to photo oxidative and thermal oxidative degradation under usage conditions due to their chemical nature. From sustainability and cost standpoint, there is an increasing focus on Mold-In-Color (MIC) plastic materials. Simultaneously customer’s expectations on the perceived quality of these MIC parts has been increasing with attractive color and glossy appearance. A study was conducted to analyze the product quality and durability aspects over a prolonged exposure to accelerated weathering condition. Material selected for this study were injection molded specimens of ABS and PC/ABS used in automotive passenger vehicles.
ENHANCE STRENGTH, ACCURACY AND PRECISION OF THE 3D PRINTED ASSEMBLY AID GAUGES Ramesh Kavalur1, Raghavendra Rao 1 1 Body in White, Manufacturing Engineering, General Motors Technical Centre India Pvt. Ltd, India, Keywords - Additive manufacturing, assembly aid gauges, 3D printer. Research Objective - Automotive manufacturing impressively implementing 3D printed jigs and fixtures. Traditional manufacturing of metal assembly aid gauges have limitations such as lead time and causes dent and rough marks on the outer panel of the body. On the other hand, 3D printed jigs and fixtures, demands more time (depends on complexity), have low level of precision and they offer lower strength. It is observed that this occurs because of the inefficient design and manufacturing without understanding the functionality and capability of the 3D printer.
The seat belt system is one of most imperative component of the safety instrument family in a vehicle. The main purpose of seat belt is to minimize the injuries by preventing the occupant from impacting hard interior parts of the vehicle and also the passenger from being thrown-out from the vehicle in case of rollover accidents. The standard three-point belts, mounted to the vehicle in three places, namely anchor, D ring and buckle. The position of D ring is very important to distribute the impact load evenly to the occupants. Very high load in any of these locations could cause breakage of the mountings and also concentrated loading on the occupant chest of pelvis. This study mainly focuses on the seatbelt assembly performance improvement against ECE-R16 sled test. The sled test was carried out first using 28g peak acceleration pulse and measurement of forces at shoulder and anchor position was measured using the load cell.
Design for Manufacturing and Assembly (DFM+A), pioneered by Boothroyd and Dewhurst, has been used by many companies around the world to develop creative product designs that use optimal manufacturing and assembly processes. Correctly applied, DFM+A analysis leads to significant reductions in production cost, without compromising product time-to-market goals, functionality, quality, serviceability, or other attributes. In this two-day seminar, you will not only learn the Boothroyd Dewhurst Method, you will actually apply it to your own product design!
Why is a design for manufacturing, assembly and automation so important? This introductory course on airframe engineering will cover the importance of design for manufacturing, assembly and automation in aerospace. It will review what the key drivers are for a “good” design and some of the key points for manufacturing and assembly of aircraft components. It will look at how an engineer can combine traditional technologies with new, cutting-edge technologies, to determine the best scenario for success.
Accurate and fast positioning of large aircraft component is of great importance for Automated Alignment System. The Ball joint is a widely-used mechanical device connecting the aircraft component and Automated Alignment System. However, there are some shortcomings for the device in man-machine engineering, such as the entry state of the ball-head still needs to be confirmed by the workers and then switched to the locking state manually. To solve above problems, a new positioning mechanism is present in this paper, which consists of a ball-head and a ball-socket. The new device is equipped with a monocular vision system, in which a calibrated industrial camera is used to collect the images of the ball-head. And then, the 3-D coordinate of the ball-head center is calculated by a designed algorithm, which combines the symmetry of the sphere and the principle of projection transformation, guiding the positioner to capture the ball-head.
The paper presents the numerical approach to simulation and optimization of A350 S19 splice assembly process. The main goal is to reduce the number of installed temporary fasteners while preventing the gap between parts from opening during drilling stage. The numerical approach includes computation of residual gaps between parts, optimization of fastener pattern and validation of obtained solution on input data generated on the base of available measurements. The problem is solved with ASRP (Assembly Simulation of Riveting Process) software. The described methodology is applied to the optimization of the robotized assembly process for A350 S19 section.
This paper documents the potential use of reconfigurable reusable jig tooling based on the box-joint system for use in the assembly of a prototype compound helicopter wing. Due to the aircraft configuration the wing design is pinned at both ends and therefore requires a higher degree of accuracy (typically 0.2mm), over the 4m length, than conventional wings. In this paper the cost benefit of reusable tooling in a low volume prototype scenario is examined followed by the design of the jig and location features to enable accurate build and metrology documentation. A prototype 4m test jig comprising of commercially available components and bespoke machined ‘pick-ups’ is presented here. Hardware and measurement process cost modelling is documented along with results for the positional and hinge-line concentricity setting accuracy that was achieved using a laser tracking system.
The Rapid And Cost Effective Rotorcraft (RACER) is being developed by Airbus Helicopters (ABH) to demonstrate a new Vertical Take-Off and Landing configuration to fill the mobility gap between conventional helicopters and aeroplanes. RACER is a compound rotorcraft featuring wings and multiple rotors. The wing arrangement suggested by ABH is defined as a staggered bi-plane joined configuration with an upper and a lower straight wing, either side of the fuselage, connected at their outboard extent to form a triangular structure. The ASTRAL consortium, consisting of the University of Nottingham and GE Aviation Systems, are responsible for the design, manufacture and assembly of the wings. Producing an optimised strategy to assemble a joined-wing configuration for a passenger carrying rotorcraft is challenging and novel. The objective of this work concerns all aspects of assembling the joined-wing structure.
Traditional Trailing Edge (TE) assembly that utilise fixtures for accurate positioning of aircraft (a/c) parts do not allow for removal of specific tooling from the fixtures to travel with the TE, post assembly. Instead, the tooling that positions all the primary a/c assembly datums generally utilise precision pins of various sizes that index and clamp the a/c ribs. Often it is difficult to remove the pins post assembly before the spar can be taken out of the fixture. Use of hammers is common place to hit pins out of holes which is less than ideal considering the a/c parts can be fragile and the tooling is precision set. Also, the Main Assembly Fixture (MAJ) that will receive the TE will inevitably need to relocate some if not all the primary a/c ribs and therefore will most likely be subject to some amount of persuasion.
ASRP (Assembly Simulation of Riveting Process) software is a special tool for modelling assembly process for large scale airframe parts. On the base of variation simulation, ASRP provides a convenient way to analyze, verify and optimize the arrangement of temporary fasteners. During the airframe assembly process certain criteria on the residual gap between parts must be fulfilled. The numerical approach realized in ASRP allows one to evaluate the quality of contact on every stage of the assembly process and solve verification and optimization problems for temporary fastener patterns. The paper is devoted to description of several specialized approaches that combine statistical analysis of measured data and numerical simulation using high-performance computing for optimization of fastener patterns, calculation of forces in fasteners needed to close initial gaps and identification of hazardous areas in junction regions.
Aircraft production is facing various technical challenges, such as large product dimensions, complex joining processes and the organization of assembly tasks. Meeting the requirements that come with large dimensions, low tolerances and small batch sizes, in combination with complex joining processes, automation and labour-intensive inspection task, is often difficult to achieve in an economically viable way. ZeMA believes that a semi-automated approach is the most effective for optimizing aircraft section assembly. An effective optimization of aircraft production can be achieved with a semi-automated riveting process for solid rivets using Human-Robot-Collaboration in combination with an intuitive Human-Machine-Interaction operating concept. While using dynamic task sharing between human and robot based on their skills, and considering ergonomics, the determined ideal solution involves placing a robot inside the section barrel.
With air traffic demand constantly increasing and several years of aircraft production in their backlog, major aircraft manufacturers are now shifting their focus toward improving assembly process efficiency. One of the most promising solutions, known as “One Side Assembly”, aims to perform the whole assembly sequence from one side of the structure (drilling, temporary fastener installation and removal, blind fastener installation, assembly control) and with a high level of integrated automation. Investments in robotic equipment, automation engineering and innovation are very active and automation capabilities have already increased a lot in the aerospace industry. As an example, drilling operations for large dimensions airframe are clearly moving from manual to automated. However, despite more and more clever and sophisticated robotics, the use of historical fasteners with two side installation method remains a strong limitation to innovative automated assembly sequences.
The substitution of aluminum for steel is an effective weight reduction solution where the application permits it; aluminum knuckles have been being widely used for this reason. However, when an aluminum knuckle is assembled with the steel outer-ring of a wheel bearing without any means for galvanic corrosion prevention, the aluminum knuckle may severely corrode. Galvanic corrosion product can make it difficult to remove a wheel bearing from the aluminum knuckle during vehicle maintenance. Prevention of this problem is the focus of this paper. In this study, several concepts were examined to prevent or mitigate galvanic corrosion between a wheel bearing and its mating aluminum knuckle. One set of concepts involves using surface treated metal sleeves (using ferritic nitro-carburizing or a special coating). The sleeves were then inserted onto the outer-ring diameters of the wheel bearings prior to assembly into the steering knuckle.
Graphite plays a crucial role in friction materials, since it has good thermal conductivity, lubricity and act as a friction modifier. The right type, amount, shape and size of the particles control the performance of the brake-pads. In this study, particles of synthetic graphite produced in a unique highly controlled graphitization process were selected to develop NAO- Cu-free brake-pads. The four types of pads had identical composition except variation in average particle size of the graphite (60 µm, 120 µm, 200 µm and 400 µm). Physical, mechanical and chemical characterization of the developed brake-pads was done. Tribological performance was studied using a full- scale inertia brake dynamometer following a Japanese automobile testing standard (JASO C406) and noise studies were done on reduced scale prototype following SAE J2521 standard.
Particulate Matter from Euro 6 Medium Duty diesel engine was analyzed from engine-out, downstream of particulate filter (DPF), and up to the exit of a selective catalytic reactor (SCR) to characterize its chemical and physical nature. Particular attention was devoted to the analysis of particles down to 23 nm. An array of chemical, physical and spectroscopic techniques (Gas chromatography coupled with mass spectrometry (GC-MS), mobility analyzer, UV-visible absorption and fluorescence spectroscopy) was applied for characterizing the organic particulate matter (PM, constituted of polycyclic aromatic hydrocarbons (PAH), heavy aromatic compounds, soot) in the exhaust. The engine was operated at “full-load” (100% of the total power, representing the best performance of the engine operation) condition, and at different engine speeds. Results showed that the DPF efficiency was greater than 96% in the reduction of the sub 23 nm particles across the speeds range.
The transient heat transfer behavior of a real size automotive catalytic reactor has been simulated with OpenFOAM in 1D. The model takes into consideration the gas-solid convective heat transfer, axial wall conduction and heat capacity effects in the solid phase, but also the chemical reactions of CO and C3H6 oxidations, based on simplified Arrhenius and Langmuir-Hinshelwood approaches. The associated parameters have been chosen based on the tuning of experimental data. The impact of different initial catalytic converter temperatures, inlet flow temperatures and inlet flow rates have been quantified, even in terms of overall cumulative emissions. . A dimensional analysis is proposed and dimensionless temperature difference and space-time coordinate are defined. Using this suitably modified coordinates, for the case of negligible axial solid conduction, computed solid temperature at the reactor outlet lay on the typical S-curve.
A raise of efficiency is, especially for CV, the strongest selling point concerning the TCO. Accompanied by legislations, with contradictive development demands, satisfying solutions have to be found. The analysis of energy losses in modern engines shows three influencing parameters. The losses resulting from taking real gas properties and non-ideal combustion into account have only a limited potential for gains, wall heat losses are currently believed to have the highest optimization potential. Critical for the occurrence of these losses is the wall heat transfer, which can be described by coefficients. To reduce WHT accompanying losses a decrease of energy transfer between combustion gas and combustion chamber wall is necessary. A measurement of heat fluxes is needed to determine the WHT relations at the combustion chamber of an engine. Methods to reduce the WHT can be developed and their effectiveness can be evaluated.