1、,AWS AWN 77 I 0784265 0000254 i ARC WELDING AND CUTTING AWS AWN 77 E 078LiZb5 0000255 O E Arc Welding and Cutting Noise A research report on one aspect of the welding environment Based on research performed at Battelle- Columbus Laboratories under contract with The American Welding Society and suppo
2、rted by industry contributions Under the direction of the AWS Committee onsafety and Health, Project Committee VI on Noise Edited by Frank Y. Speight, Secretary, and Hallock C. Campbell, Consultant AMERICAN WELDING SOCIETY 2501 N“! 7th Street, Miami, FL 33125 Library of Congress Number: 79-51314 Int
3、ernational Standard Book Number: 0-87171-176-1 American Welding Society, 2501 N.W. 7th Street, Miami, FL 33125 01979 by American Welding Society All rights reserved Note: By publication of this book, the American Welding Society does not insure anyone utilizing the book against liability arising fro
4、m its use. A publication of a book or standard by the American Welding Society does not carry with it the right to make, use, or sell any patented items, Each prospective user should make an independent investigation. Printed in the United States of America AWS AWN 79 07842b5 0000257 4 Contents Pers
5、onnel . v Acknowledgement vi Summary . 1 Introduction . 2 TechnicalDisciission 2 AWS Method for Sound Level Measurement of Manual Arc Welding and Cutting Processes . 2 6 . Equipment 2 CommentsonSection6 . 2 7 . Precautions 4 Comments on Section 7 6 8 . Sampling 7 CommentsonSection8 . 7 9 . Preparati
6、on of Equipment . 7 CommentsonSection9 . 8 10 . Calibration Comments on Section 10 11 . Procedure . Comments on Section 11 . 12 . Report . Comments on Section 12 . Results and Conclusions . Recommendations for Future Work Appendix A: Method for Sound Level Measurement of Manual 8 8 . 8 8 9 9 9 10 .
7、rc Welding and Cutting Processes . 11 Appendix B: Table B1 and Data Sheets for Noise Measurement of Arc Welding and Cutting Processes 19 AWS AWN 77 078q2b5 0000258 b I Personnel :. . AWS Committee on Noise N. B. Shankland, Chairman E Z Speight. Secretary K. L. Brown N. De Tarnowsb O. J. Fisher R. He
8、ytnann* A. E Manz J. A. Northlip, Jr. C. Rodman E Sachs D. W Schmerling J. S, Senesky C. E. Strain H. Trabbold *Presently with U.S. Environmental Protection Agency Sciaky Brothers, Incorporated American Welding Society Lincoln Electric Company American National Standards Institute Babcock and Wilcox
9、 U.S. Army Environmental Hygiene Agency Linde Division, Union Carbide Corporation Norton Company Battel le-Columbus Laboratories U.S. Army Environmental Hygiene Agency Alloy Rods Division, Airco Welding Products Hobart Brothers Company Arcair Company Allegheny Ludlum Industries V AWS AWN 79 m 078426
10、5 0000259 8 Acknowledgement This report was prepared by Charles W. Rodman, Lynn Faulkner, and Donald Skaggs of Battelle-Columbus Laboratories, dated November 4, 1977. For publication it was edited by Frank Y. Speight and Hallock C. Campbell to AWS style, and the final version of AWS F6.1-78, Method
11、for Sound Level Measurement of Manual Arc Welding and Cutting Processes, has been substituted for the draft version supplied to Battelle. Measurem AWS AWN 79 - 0784265 00002b0 4 - Arc Welding and Cutting Noise SUMMARY nts of the noise produced by four arc weld- ing processes and one arc cutting proc
12、ess were evaluated under standardized measurement conditions now incor- porated in AWS F6.1-78, Method for Sound Level Mea- surement of Manual Arc Welding and Cutting Processes. Several important areas were surveyed or reviewed: (I) Measurement equipment and calibration procedures (2) Qualification
13、of the measurement space acous- (3) Evaluation of the sound measurement procedures The conclusions regarding these items are as follows: (I) Equipment. Manufacturers procedures and recommendations must be followed with regard to cali- bration of sound measuring instruments, microphone placement (rel
14、ative to observer and reflecting surfaces), microphone orientation (angular orientation of micro- phone axis in relation to sound source), and wind screen corrections. Using the recommended procedures, repeat- able measurements within stated limits can be obtained. (2) Measurement space. Qualificati
15、on of the mea- surement space was found to be less difficult than antici- pated. The major criteria are background sound levels due to other sources in the space, reflection of sound tically in the qualified space from room surfaces, and physical size of the space. The background sound levels should
16、 be a minimum of 10 dB below the levels to be measured from the welding process. Acoustically reflecting surfaces, particularly walls, mustbe covered temporarily during measurements. This can be easily achieved by using 4 ft x 8 ft x 2 in. (I .22 x 2.44 x 0.05 m) high-density glass fiber panels to c
17、ompletely surround the measurement location. These panels need not be permanently attached to walls. The room within which the acoustic measurements are to be taken must be large enough to allow microphone position- ing at specified locations that will not be close to room surfaces: that is, walls o
18、r ceiling. It is recommended that at least 8 ft (2.44 m) of clear space be available on all sides and above the welding table. (3) Measurement procedure. The measurement procedure described in the proposed stanard was found to be acceptable for determination of noise levels from welding processes. I
19、t is important to maintain the weld- ing process as nearly as possible in a stationary loca- tion while making noise measurements. A stationary source and a moving workpiece are recommended. Recommendations are made for future investigation of the procedure sensitivity to small variations in locatio
20、n of microphones, and to variations in spectra of the pro- cess noise and the ambient sound. Conducting a round robin test of this method is also recommended. 1 AWS AWN i9 a 07LIZb5 00002bL b 2/ARC WELDING AND CUTTING NOISE , INTRODUCTION As part of an overall program to investigate the in- fluence
21、of welding operations on the environment of the workplace, Battelle-Columbus Laboratories carried out a series of noise measurements designed to quantify the noise generated by arc welding and cutting processes. The measurement procedure was selected by the Amer- ican Welding Societys Safety and Hea
22、lth Project Com- mittee VI on Noise. The processes to be measured were selected by Project Committee VI11 on Research. In addition to obtaining data on process noise, one of Battelles objectives, as specified by AWS, was to evaluate the effectiveness of the proposed AWS F6.1-78, Method for Sound Lev
23、el Measurement of Manu.al Arc Welding and Cutting Processes, at that time not yet approved for publication. Over half of the Battelle effort consisted of partici- pation in the deliberations of the Committee on the draft procedure and in preliminary evaluation of the room qualification requirements
24、of the procedure. The ad hoc task group charged with drafting the procedure released the procedure to Battelle on July 19, 1977, and the list of processes to be measured was received from the Re- search Committee approximately one week later. Mea- surements were started on August 9, 1977, and comple
25、ted August 16,1977. TECHNICAL DISCUSSION The proposed Method for Sound Level Measurement of Manual Arc Welding and Cutting Processes was followed as closely as possible in order to evaluate the effective- ness of the document. In some cases additional measure- ment locations and process settings wer
26、e used to provide insight into the sensitivity of the results to these variables, No attempt was made to analyze the results obtained since this was not included in the scope of the research program. However, comments on the results are in- cluded, where appropriate. The format for the following dis
27、cussion of the stan- dard and its application consists of statements of each section, alternating with descriptions of the manner in which Battelle used each section in carrying out the measurements, AWS Method for Sound Level Measurement of Manual Arc Welding and Cutting Processes The draft standar
28、d, as finally presented to Battelle, was essentially the same as the standard now published. The experimental conditions to be tested were chosen by the AWS Committee on Noise and were those listed in the standard, plus readings with the microphone at the position occupied by the welder or welding o
29、perator. Following are sections of the draft procedure used by Battelle in performing the noise measurements, The approved standard procedure appears as Appendix A. 6. Equipment 6.1 Sound level measurements shall be made using a sound level meter configuration conforming with the requirements of ANS
30、I S1.4 (paragraph 2.1) for type I meters. 6.2 Equipment shall be located in accordance with Fig.Al in Appendix A, p. 18. 6.3 The equipment shall be used in a test site that meets the requirements of 9.1 (for outdoor locations), or 9.2 (for semianechoic test rooms), or 9.3 (for in-plant locations). 6
31、.4 Octave band filter sets, if used, shall meet the re- quirements of ANSI SI.11-1966 for Class II filters. The octave band frequencies shall be those tabulated in Note: The actcriv bniid filter set is required oiily for the evnliiii- tiori of the acoustic eiiviroiiiiietit occurring nt the test site
32、. ANSI S1.4-1971. Comments on Section 6 6.1 The sound level meter used by Battelle was the GenRad Model 1933 Precision Sound Level Meter with Octave Band Analyzer. A one inch (25.4 mm) electret microphone with a foam wind screen recommended by GenRad was used for the measurements. The wind screen in
33、troduces less than -0.5 dB error at frequencies up to 5 kHz, and approximately 2 dB in the range 5 kHz to 12 kHz. The effect of the wind screen on A-weighted broad band sound cannot be predicted unless the spec- tral content of the sound is known; however, the error should not exceed 2 dB, 6.2 Figur
34、e I, p. 3, shows the layout of the measurement area used. The sound level measurements of manual arc welding and cutting processes were conducted in a simu- lated in-plant location. The test site was a laboratory space in a steel frame building with corrugated steel panel walls. The acoustical absor
35、ption of the thermal insulation on the inside of the walls was augmented by placing 4 ft by 8 ft by 2 in. (1.22 x 2.44 x 0.05 m) high-density acous- tical glass fiber panels around the perimeter of the measure- ment space. The dimensions of the building, consisting of a single open area, are 18 ft b
36、y 60 ft (5.49 by 18.29 m) long, by 14 ft (4.27 m) high. The measurement space, as defined by the acoustically absorbent panels, was 24- 1 /2 ft by 17-1/4 ft (7.47 x 5.26 m). The test site had a concrete floor extending the width of the room. The glass fiber panels were at a distance of no less than
37、5 ft (1.52 m) from any measurement point. I. The panels used have a densify of 0.375 ib/ft (1.83 kglm). AWS AWN 77 m 07842b5 0000262 however, for one set of measurements (GTAW), the process noise level was so low it was not feasible to do so. 7.1.4 The wind screen was inspected frequently for damage
38、 by weld splatter. No damage was incurred during the measurement program. 7.1.5 All sound level measurements were made with the welding power supply placed outside the building in which the test room was located. The sound level meter (except for the microphone) and the voltage and current meters we
39、re placed outside the boundaries of the test area, beyond the absorbant panels. A microphone exten- sion cable conforming to the recommendations of the meter manufacturer was used. The only person inside the test area at the time of the measurements was the welder. When GMA and FCA welding were perf
40、ormed, AUS AWN 79 m 07842b5 00002bb 5 I Technical Discussion 17 a wire feeder was located in the test area. The wire feeder gun was rigidly supported above the table at the correct distance for the test being conducted. (It should be noted that the wire feeder was in the test area only when GMA and
41、FCA welding were performed.) 7.1.6 The microphone, with an approved windscreen, was oriented in accordance with the manufacturers in- structions in order to yield the flattest possible frequency response at free field conditions. 7.1,7 A series of measurements was made with a dummy microphone instal
42、led on the microphone pre- amplifier. The meter indication. remained at 22 dBA when the arc was operating, indicating no influence by the arc or cable fields on the preamp or the line leading to the remote sound levei meter. 7.2 The welding operator was an experienced welder on the Battelle technica
43、l staff. He is familiar with the requirements of ANSI 249-1 and the need to comply with the special requirements of the draft procedure. He is the same operator who assisted with the ventilation tesfs and the fume tests conducted as part of the overall AWSIBattelle program. Other personnel remained
44、out- side the test area, behind the acoustic panels. 8. Sampling 8.1 Measurements shall be made at locations specified in Fig. L3p. 15. 8.2 Measurements shall be recorded on a form essenfially similar to that shown in Fig. 2,3 p. 16. 8.3 Case conditions shown on Fig. 2,3 p. 16. 8.3.1 Case A.-Al1 equ
45、ipment operating but without arc initiation. This may require relocation of some equip- ment outside of the test site, in order to meet the require- ments of paragraph 7. i. 8.3.2 Case B-Maximum recommended operating parameters for the process being measured when the equipment range is adequate to s
46、upply process power. Otherwise maximum recommended equipment setting is used to establish the process operating parameters. Refer to paragraphs 2.6 and 2.7. 8.3.3 Case C-Minimum recommended operating parameters for process being measured when the equip- ment range isadequate to supply the process po
47、wer. Other- wise minimum recommended equipment setting is used to establish the process operating parameters. Refer to paragraphs 2.6 and 2.7. Comments on Section 8 8.1 The sound level measurements were made at the five locations shown in Fig. 1 of AWS F6.1-78, see p. 15, and at the level of the wel
48、ders ear (M6), see Fig. AI, p. 18. 8.3 Three case conditions were investigated for each type of welding. Case A measurements were ambient readings with the equipment operating but with no arc. Case B measurements were made with maximum recom- mended operating conditions for the process being mea- su
49、red. When the equipment range was not adequate to supply process power, maximum recommended equip- ment settings were used to establish the process operating conditions. Case C measurements were made within min- imum recommended operating conditions for the process being measured. When the equipment range was not adequate to supply the specified process power, the min- imum recommended equipment setting was used to es- tablish the process operating conditions. On some oc- casions, a Case D measurement was taken. Case D mea- surements were made with average or normal operating condi
