Noise and Vibration Comparison Steel Lining versus Rubber Lining. Charles Hillmann

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2 Noise and Vibration Comparison Steel Lining versus Rubber Lining Charles Hillmann

3 Course Agenda Study Generated By Elna Hoven Aim of the study: Study the effect of noise and vibration levels on Equipment & Operators Comparison between Steel lining in Haul Trucks versus Rubber Lining.

4 Procedure Measurements has been taken at two different occasions before and after rubber lining in an open cast area. ( and ) # 3 weeks Totally 20 different test runs were preformed The truck was loaded with 2 buckets and then completely emptied Test object CAT 775 F loaded by a CAT 990 II.

5 Studied Parameters Interior noise Exterior noise Structural vibrations Seat vibrations

6 LAF and Equivalent noise Level Sound Level db(a) Max Sound Level (LAF) 85dB(A) Equivalent Sound Level 67 db(a) Time (s)

7 Location of interior microphones

8 Interior Equivalent sound pressure level 90 Steel 1bucket 86 85,8 Steel 2 bucket 82,1 81,9 Steel background Sandvik Rubber1 80 Sandvik Rubber2 db(a) re 2e-5P Pa 70 66,8 68,4 67,5 66,6 69,2 68,5 67,5 67,5 Rubber background 60 Int L (A) Int R (A)

9 Interior LAF max ,6 94,2 91,8 Limit for when protection is needed db(a) re 2e-5Pa ,2 79, ,2 67,9 78,6 74,2 68 Steel 1bucket Steel 2 bucket Steel background Sandvik Rubber1 Sandvik Rubber2 Rubber background 60 Int L (A) Int R (A)

10 Interior time weighing fast sound pressure level with steel lining, LAF max Maximum noise level from the first bucket for the for the 5 test runs. High noise level for 5-6 seconds db(a) re 2e e-5 Pa Background level

11 Interior time weighing fast sound pressure level with Rubber Lining, LAF max 90 Maximum noise level from the first bucket for the for the 5 test runs. Reduced noise level High noise level for 1-2 seconds 5 Pa db (A) re 2e Background level

12 Location of exterior microphone

13 Exterior Equivalent sound pressure level 100 Steel 1bucket 90 90,3 Steel 2 bucket Steel background 83,8 Sandvik Rubber1 db(a) re 2e5Pa ,7 74,8 75,6 68,8 Sandvik Rubber2 Rubber background 60

14 Exterior LAF max Steel 1bucket 120 Steel 2 bucket Steel background db(a) re 2e-5Pa ,6 92,5 69,2 80,3 82,6 70,6 Sandvik Rubber1 Sandvik Rubber2 Rubber background 60 Ext db(a)

15 Exterior time weighing fast sound pressure level with steel lining LAF max Maximum LAF as a funtion of time for 5 test runs when steel lining e-5 Pa db(a) re Background noise level

16 Exterior time weighing fast sound pressure level with Rubber Lining, LAF max 85 Maximum LAF as a funtion of time for 5 test runs when Sanvik Rubber Lining LAF max = 80,3 db(a) Pa db(a) re 2e Background noise Time, (s)

17 Definition of global coordinate-system

18 Location of accelerometer

19 Structural Vibrations RMS amplitude e, m/s2 The dominating vibration direction Body X Body Y Body Z Steel 1bucket Steel 2 bucket Steel background Sandvik Rubber1 Sandvik Rubber2 Rubber background With Rubber Lining vibrations are almost as low as the background vibrations!

20 Acceleration as function of time Vibration time history signal (Z) m/s 2 Peak level is typically 8 times higher for steel lining compared to Sandvik Rubber Lining Time, (s) Sandvik Rubber Lining correspond to background vibration Steel Lining

21 Seat Vibration Seat pad accelerometer

22 Seat Vibrations Weighted RMS amplitude m/s2 0,5 0,4 0,3 0,2 0,1 Weighted RMS amplitude for seat Steel 1bucket Steel 2 bucket Steel background Sandvik Rubber1 Sandvik Rubber2 Rubber background Only minor effect on the vibrations in the seat 0 a_v Seat X*Kx Seat Y*Ky Seat Z*Kz

23 Summary Exterior reduction: eqv : 15 db(a) and LAF:20 db(a) Interior reduction: eqv: 17 db(a) and LAF: 15 db(a) Structural vibrations: RMS reduction factor of 5 Instantaneous peak acceleration over time: Reduction factor of 8. Seat vibrations: minor

24 CONCLUSION Major interior and exterior noise reduction gives a much better environment for both workers and neighbors. Now proved and quantified. The reduction of the structural vibrations has major benefits for the truck body when it comes to fatigue and welds. Life time of the truck structure will increase. Only a minor effects on seat vibrations was achieved due to an effective seat air suspension system. For the driver those minor reductions makes a big impact in the longer perspective.

25 Context for all Presentations: Why are we presenting the material we propose to cover? Where does it fit in the value chain? How does it impact total cost / value enhancement/safety issues? What is the specific informational take-away for student for application in his quarry? What does this presentation deliver to the student? Answer the following questions in the mind of the student: What? Now What? So What? (What is being covered) (What do I do now with this information) (What is the significance of this knowledge or action)

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