Mapping of grounding applications regarding Volvo S80/XC90, VCBC´s assortment Tommy Mikalsen Jörgen Ahnstedt Andreas Agardh School of Engineering Department of Mechanical Engineering BTH- Blekinge Institute of Technology Karlskrona 2004 © (This entire report is copywrite protected by the authors. Information in this report, including but not limited to, text and images may not, except for Volvo Cars Corporation, be reproduced, transferred, distributed or storaged without prior written permission by the authors. Modifications to the contents of this report are expressly prohibited.) ii Summary The high technology cars of today contain an enormous amount of advanced electronic equipment. To ensure the function of the electrical system these must be grounded in the body of the car. The grounding is made possible by welding unthreaded nuts into the body of the car. If the grounding doesn’t work as it should in the car, the strangest defects can occur and they can be very hard to locate. To maintain the functionality of the entire electronic system it’s of the highest importance to get an adequate grounding capability on the grounding element. The project is like an element in VCBC:s work to meet Volvos goal: “To be No. 1 in customer satisfaction in the premium segment of the car industry.” [7] The purpose is to increase the communication and widen the individually understanding in all segments within the company. The most important task is, and will always be, to deliver a car without any ground related problems to the costumers even in the future. Measurements and physical tests have been done and the results have been documented in a thorough and clear way so that it will be easy to track and identify the actual grounding connections. The work has been of investigating character and included information retrieval, information sorting and information documentation. The result of our work is going to be a great help regarding possible changes and investigations of the cars electrical system. (*) (*) : Consideration is taken to valid secrecy agreement. iii iv Sammanfattning Dagens högteknologiska bilar innehåller en ofantlig mängd avancerad elektronik. Denna elektronik måste jordas i karossen för att elsystemet skall fungera. Jordningen sker med hjälp av ogängade muttrar som svetsas fast i karossen. Om jordningen inte fungerar som den skall på en bil så kan de mest märkvärdiga fel uppkomma och dessa är mycket svåra att lokalisera. För att bibehålla funktionaliteten på samtliga elektroniska system är det av högsta betydelse att få fullgod jordningsförmåga hos jordningselementen. Projektet sker som ett led i VCBCs arbete att tillgodose Volvos mål: "Att vara främst inom kundtillfredställelse i premiumsegmentet." [7] Syftet är att utöka kommunikationen och vidga den individuella förståelsen i samtliga led inom företaget, och ytterst att leverera en bil till kund som är fri ifrån jordfel även i fortsättningen. Projektet har resulterat i en sammanfattning av gällande mål. Mätning har skett och resultaten har dokumenterats för att på ett överskådligt sätt kunna spåra och identifiera de aktuella jordningsförbanden. Arbetet har varit av utredande karaktär och inneburit informationssökning, informationssortering och informationsdokumentation. Resultatet av vårt arbete kommer att vara till stor hjälp vid eventuella gällande och kommande förändringar och undersökningar av bilens elsystem. (*) (*): Hänsyn är tagen till gällande sekretessavtal. v vi Preface The following work is made as a compulsory part of the education on the programme Product Development at the Department of Mechanical Engineering, BTH (Blekinge Institute of Technology). We would like to thank all the employees at VCBC in Olofström for shown interest and help regarding our work. We want to send a specific thanks to Mrs. Lea Bengtsson who has been our supervisor during the work and Mr. Anders Boking, head of the department for process development. The authors, Karlskrona 01-June-2004 Tommy Mikalsen ____________________________________ Jörgen Ahnstedt ____________________________________ Andreas Agardh vii viii Table of contents Summary___________________________________________________iii Sammanfattning______________________________________________v Preface ___________________________________________________ vii Notations__________________________________________________xiii 1 Welcome _______________________________________________ 1 2 Project definition ________________________________________ 3 2.1 Denomination _______________________________________ 3 2.2 Purpose ____________________________________________ 3 2.3 Content ____________________________________________ 4 3 Corporate presentation ___________________________________ 5 3.1 The promise_________________________________________ 6 3.2 The vision __________________________________________ 6 3.3 The mission _________________________________________ 6 3.4 The culture _________________________________________ 6 3.5 Corporate philosophy _________________________________ 6 3.6 History of Volvo______________________________________ 7 4 Presentation of the cars ___________________________________ 8 4.1 P23 (S80) ___________________________________________ 8 4.2 P28 (XC90) _________________________________________ 9 5 Presentation of resistance welding _________________________ 10 5.1 Projection welding ___________________________________ 11 6 Presentation of the grounding nuts_________________________ 13 6.1 Flange weld nuts UT6, UT8 ____________________________ 13 6.2 Flange weld nuts HP UT6, HP UT8 ______________________ 13 7 Presentation of the materials______________________________ 14 7.1 Steel V-1158________________________________________ 14 7.2 Steel V-1343________________________________________ 14 7.3 Steel V-1357________________________________________ 14 ix 7.4 Steel V-1423 ________________________________________ 14 7.5 Steel V-1568 ________________________________________ 14 7.6 Steel V-1148 ________________________________________ 15 7.7 Steel V-1157 ________________________________________ 15 7.8 Steel V-1437 ________________________________________ 15 7.9 Steel V-1478 ________________________________________ 15 7.10 Welding in zinc-coated materials ________________________ 15 7.11 Coating ____________________________________________ 16 8 Used equipment_________________________________________17 8.1 Push out test ________________________________________ 17 8.2 Machine measuring___________________________________ 18 9 Procedure______________________________________________19 10 Results ______________________________________________23 11 Discussion of the results________________________________25 11.1 Types of failure ______________________________________ 25 11.2 Résumé ____________________________________________ 26 12 Visualization of the result _______________________________30 12.1 UT6/P23 ___________________________________________ 30 12.2 UT8/P23 ___________________________________________ 31 12.3 HPUT8/P23_________________________________________ 31 12.4 UT6/P28 ___________________________________________ 32 12.5 UT8/P28 ___________________________________________ 33 13 Time schedule ________________________________________34 13.1 Graphics ___________________________________________ 34 13.2 Explanations ________________________________________ 35 14 Conclusions__________________________________________36 15 Thanks ______________________________________________37 16 References ___________________________________________38 16.1 Pictures____________________________________________ 38 16.2 Written text_________________________________________ 38 x Appendix A________________________________________________ 41 P23/S80, General information ________________________________ 41 Part specification__________________________________________________41 Nut specification __________________________________________________42 Material specification ______________________________________________43 Machine specification ______________________________________________44 Data ___________________________________________________________45 Appendix AA ______________________________________________ 46 P23/S80, Specific information ________________________________ 46 Cross member Front Left____________________________________________46 Cross member Front Right __________________________________________47 Cover Side member Upper Left _______________________________________48 Cover side member Upper Right ______________________________________49 Body side Inner Right ______________________________________________50 Bracket Sill Fender Right ___________________________________________51 Bracket Sill Fender Left ____________________________________________52 Plate Side Member Left _____________________________________________53 Cover Plate Side Member External Left_________________________________54 Wheel Housing Inner Front Left ______________________________________55 Cover Plate Rear Side Member Left ___________________________________56 Cover Plate Rear Side member Right___________________________________57 Endplate Rear ____________________________________________________58 Appendix B________________________________________________ 59 P28/XC90, General information_______________________________ 59 Part Specification _________________________________________________59 Nut specification __________________________________________________60 Material specification ______________________________________________61 Machine specification