海工產(chǎn)品檢驗員手冊

1、CONTENTS目錄備注SNo.TITLES標題1Welder Position Qualification and Range 焊工位置評定及范圍2Welding Positions 焊接位置3AWS specifications for electrodes AWS焊條規(guī)范4Electrode deposition efficiency and stub loss factors焊條熔敷效率和損耗系數(shù) 5Typical shielded metal arc electrode orientation and welding technique for carbon steel electr

2、odes 炭鋼手工電弧焊條操作的典型方位及技能6Suggested amperage ranges for carbon steel and low-alloy steel electrodes 碳鋼和低合金鋼焊條的推薦電流范圍7Troubleshooting mechanical problems encounterd in GMAW and FCAW-G GMAW 和 FCAW-G 焊接中存在的機械問題與修復8Weld discontinuity causes and remedies-cracks 裂紋導致的焊縫不連續(xù)的返修9Weld discontinuity causes and r

3、emedies-inclusion 夾渣導致的焊縫不連續(xù)的返修10Weld discontinuity causes and remedies-incomplete fusion 未熔合導致的焊縫的不連續(xù)的返修11Weld discontinuity causes and remedies-incomplete joint penetration 未焊透導致的焊縫不連續(xù)的返修12Weld discontinuity causes and remedies-overlap焊瘤導致的焊縫不連續(xù)的返修13Weld discontinuity causes and remedies-porosity

4、密集氣孔導致的焊縫不連續(xù)的翻修14Weld discontinuity causes and remedies-undercut咬邊導致的焊縫不連續(xù)的返修15Weld profiles焊縫外形16Fillet weld measurement 角焊縫的測量17Dimensional considerations 尺寸檢查18Proper care and handing of SMAW electrodes SMAW焊條的正確管理與發(fā)放19Special precautions for low-hydrogen electrodes 低氫焊條管理的特殊要求20Drying condition

5、for welding consumable焊接耗材的干燥條件一、Welder position qualification and range 焊工位置評定及范圍Qualification評定Range qualified評定范圍1F2F3F4F5F1G2G3G4G5G6G6GR3F4F3G4G5G6G6GRWelding positionsgroove(plate)焊接位置坡口（板）1G 2G3G4GWelding positionsfillet(plate)焊接位置角焊縫（板）1F(FLAT平焊) 2F(HORIZONTAL橫焊) 3F(VERTICAL立焊) 4F(OVERHEAD仰焊

6、)Welding positions pipe焊接位置管1G ROTATED旋轉(zhuǎn) 2GWelding positions pipe (continued)焊接位置管5G 6G 6GR; T.K.Y 連接二、AWS Specifications for electrodes AWS焊條規(guī)范Type of electrode焊條類型AWS specifications AWS規(guī)范SMAWFCAWSAWGTAW,GMAWCarbon steel 碳鋼5.15.205.175.18Low alloy steel 低合金鋼5.55.295.235.28Stainless steel 不銹鋼5.45.22

7、5.95.9 , 5.22Aluminium and its alloy 鋁和鋁合金5.35.10Copper and its alloy 銅和銅合金5.65.7Nickel and its alloy 鎳和鎳合金5.115.145.14三、Electrode deposition efficiency and stub loss factors焊條的熔敷效率和損耗系數(shù)CLASS AVERAGE EFFICIENCY * STUB LOSS *等級 平均熔敷效率端頭損耗E6010 63.8% STUB（殘余長度） 5/32E6010 14in E6011 68.5% LENGTH %DEPOS

8、IT（沉淀物） %LOSSE6012 66.9% 2in 63.8 36.2E6013 66.8% 3in 58.5 41.5E7014 64.6% 4in 53.2 46.8E7016 62.8% 5in 47.9 52.1E7018 69.5% 6in 42.6 57.4E6020 65.2% WEIGHT OF WELD METAL(焊接金屬重量)E7024 66.8% EFFICIENCY熔敷效率WEIGHT OF ELECTRODE USED INCLUDING STUB（使用焊條的重量，包括殘余部分）E7027 68.3% * INCLUDES 2 in STUB LOSS包括殘余

9、部分的2in* E6010 IS 71.57% EFFICIENCY ,LOSS DUE TO SLAG , SPATTER AND SMOKE E6010熔敷效率只有71。57% ，由于焊渣、飛濺和煙的損失四、Typical shielded metal arc electrode orientation and welding technique for carbon steel electrodes 碳鋼手工電弧焊條操作的典型方位與技能Type of joint (接頭類型)Position of welding焊接位置Work angle degrees操作角度 Travel angl

10、e degrees*運條角度Technique of welding焊接技能Groove坡口Flat平焊905-10*Backhand 反手Groove坡口Horizontal橫焊80-1005-10Backhand反手Groove坡口Vertical-up立向上905-10Backhand反手Groove坡口Overhead仰臉905-10Backhand反手Fillet 角焊Horizontal橫焊455-10*Backhand反手Fillet 角焊Vertical-up立向上35-555-10Forehand正手Fillet 角焊Overhead 仰臉30-455-10Backhand反

11、手* Travel angle may be 10to30for electrodes with heavy iron powder coatings. 對于重鐵粉藥皮的焊條運條角度可以成10-30度的角五、Suggested amperage range for carbon steel and low-alloy steel electrodes碳鋼和低合金鋼焊條的推薦電流范圍Electrode 焊條Diameter(in)尺寸（英寸）Amperage (A)電流E6010 and E60113/321/85/323/167/3250-70100-130140-170160-190190-

12、230E60121/85/323/167/321/4100-130165-200220-240275-320320-380E60133/321/85/323/167/3260-75100-135140-180180-220250-290E70183/321/85/323/167/3270-110120-160150-200200-275250-340E70241/85/323/167/321/4140-180180-240245-290320-360400-450六、Troubleshooting mechanical problems encountered GMAW and FCAW-GG

13、MAW 和 FCAW-G 焊接中存在的機械問題與修復Problem 問題Possible cause可能存在的原因Remedy 修復Irregular wire feed and burnback送絲不均及燒穿Insufficient drive roll pressure送絲滾輪壓力不足Contact tube plugged or worn焊嘴堵塞或者損壞Kinked electrode wire 焊絲打結(jié)Coiled gun cable把線纏繞Conduit liner dirty or worn導管襯墊太臟或者損壞Conduit too long送絲軟管太長Adjust調(diào)節(jié)Clean

14、or replace 清潔或者更換Cut out ,replace spool去除打結(jié)部分更換線軸Straighten cable ,hang the wire feeder捋直把線，將送絲裝置停止Clean or replace清潔或更換Shorten or use push-pull drive system截短或者用自動伸縮系統(tǒng)Electrode wire wraps around drive roll(birdnesting)焊絲在送絲滾輪和軟管進口處發(fā)生卷曲或打結(jié)Excessive feed roll pressure送絲滾輪壓力過大Incorrect conduit liner o

15、r contact tip襯墊或者導嘴不匹配導致Misaligned drive roll or wire guides 送絲滾輪和導絲裝置不在一條線上Restriction in gun or gun cable焊槍或把線受阻Adjust調(diào)節(jié)Match liner and contact trip to electrode size 使用與焊絲尺寸一致的襯墊和導嘴Check and align properly檢查并正確調(diào)整Remove restriction 去除阻力Heavily oxidized weld deposit熔敷金屬嚴重氧化Air/water leaks in gun an

16、d cable空氣或水滲入焊槍或把線中Restriction shield gas flow 保護氣體流動受限Check for leaks and repair or replace as necessary必須檢查漏點并修理，或更換Check and clean nozzle檢查清潔焊槍嘴Electrode wire stops feeding while welding在焊接當中停止送絲Excess or insufficient drive roll pressure送絲滾輪壓力過大或者不足Wire drive rolls misaligned or worn送絲滾輪方向偏離或者損壞L

17、iner or contact tube plugged襯墊或軟管堵塞Adjust 調(diào)節(jié)Realign and/or replace重新對接或者更換Clean or replace清潔或更換Wire feeds but no gas flows送絲時沒有保護氣流入Gas cylinder is empty氣瓶內(nèi)氣體不足甚至沒氣Gas cylinder value closed氣瓶閥門關閉Flow meter not adjusted氣體計量表未調(diào)整Restriction in gas line or nozzle氣管或槍口被堵塞Replace and purge lines before we

18、lding焊接前更換氣瓶 Open cylinder valve打開氣瓶閥門 Adjust to give flow specified in the procedure按照制定的調(diào)整程序調(diào)整氣體流量Check and clean 檢查并清理 Porosity in the weld bead焊接中出現(xiàn)氣孔Failed gas valve solenoid電磁氣閥失靈Gas cylinder valve closed 氣瓶閥門關閉Insufficient shielding gas flow 保護氣體流量不足Leaks in gas supply lines(including the gun

19、)氣管泄漏（包括焊槍）Repair or replace 修復或者更換Turn valve on 打開閥門Check for restrictions in gas line or nozzle and correct檢查受限氣管或噴嘴并糾正Check for leaks(especially at connections)and correct 查找泄漏并修復（特別注意連接處）Wire feed motor operates but wire does not feed 送絲器啟動，但是焊絲并未伸出Insufficient drive roll pressure送絲滾輪壓力不足 Incorr

20、ect wire feed rolls送絲滾輪不匹配Excessive pressure on wire spool brake引線卷軸的制動壓力過大Restriction in the conduit liner or gun 焊槍與軟管不匹配Incorrect liner or contact tube軟管與導絲接頭不匹配Adjust 調(diào)節(jié)Match feed rolls to wire size and type使用尺寸型號一致的送絲滾輪Decrease brake pressure 減小制動壓力Check liner and contact tip 檢查接頭墊片Clean and/or

21、 replace清理或者更換Check and replace with correct size檢查更換合適的尺寸Welding gun overheats焊槍發(fā)熱Pinched or clogged coolant line 冷卻管受擠壓或者堵塞Low coolant level in pump reservoir 冷卻液低于泵以下Water pump not functioning correctly水泵不能正常工作Check and correct 檢查修正Check and add coolant as necessary按照要求檢查增加冷卻液Check and repair or

22、replace檢查并修理或者更換七、Troubleshooting electrical problems encountered in GMAW and FCAW-G GMAW and FCAW-G 焊接中電氣問題的修復Problem 問題Possible cause可能存在的原因Remedy 修復Difficult arc starting起弧困難Wrong polarity電路錯誤Poor work lead connection工作導線連接不好Check polarity; reverse leads if necessary檢查電路，如果需要顛倒導線Secure work lead

23、connection正確連接Irregular wire feed and burnbackl送絲不均，燒穿Power circuit fluctuations 電壓不穩(wěn)定Polarity wrong 電路錯誤Check line voltage 檢查電壓Check polarity ; reverse leads if necessary 檢查電路，如果需要顛倒導線Welding cables overheating 焊接時電纜發(fā)熱Cables are too small or too long 電纜太細或者太長Cable connections loose 電纜連接松弛Check curr

24、ent carrying requirementsreplace or shorten if necessary 檢查電流輸送要求更換或者縮短如果需要Tighten緊固No wire feed speed control 送絲速度控制裝置損壞Broken or loose wires in control circuit 控制裝置損壞或松散Bad P.C.board in governor 控制面板損壞Check and repair if necessary如果需要檢查修復更換控制面板Unstable arc電弧不穩(wěn)Cable connections are loose 電纜連接松弛Tigh

25、ten connections緊固線路Electrode wont feed不送絲Control circuit fuse blown 控制系統(tǒng)保險絲損壞Fuse blown in power source電源保險絲損壞Defective gun trigger switch or broken wire leads焊把觸發(fā)開關損壞或者導線連接斷開Drive motor burned out驅(qū)動電機燒壞Repair fuse修理保險絲Replace fuse更換保險絲Check connections ; replace switch 檢查線路;更換開關Check and replace檢查更

26、換 Wire feeds but no gas flows送絲時沒有保護氣流入Failure of gas valve solenoid氣閥螺旋管失靈Loose or broken wires to gas valve solenoid 氣閥螺旋管松動或者損壞Replace 更換Check and repair if necessary 檢查如果需要進行修理Electrode wire feeds but is not energized (no arc)焊絲不產(chǎn)生電弧Poor workpiece connection 焊件連接不好Loose cable connections 導線連接松散P

27、rimary contactor coil or points defective控制繼電器的觸點燒損或其線圈燒損Contactor control leads broken電流接觸器的控制電路損壞Tighten if loose ; clean work of paint, rust, etc.固定;清理焊接區(qū)域的油漆,刷銹等Tighten 擰緊Repair or replace修理或者更換Repair or replace修理或者更換Porosity in weld 焊縫產(chǎn)生氣孔Loose or broken wire to gas solenoid valve氣閥螺旋管松動或已損壞Rep

28、air or replace修理或者更換八、Cracks 裂紋A crack is defined as “A fracture type discontinuity characterized by a sharp tip and a high ratio oflength and width to opening displacement.” Cracks are usually considered the most severe discontinuity because of their tendency to propagate under stress. Cracks are u

29、sually furtherdescribed by their location geometry ,time of occurrence ,or common usage terms ; see figure below for AWS crack terminology .裂紋被定義為: “斷裂形不連續(xù),表現(xiàn)為端部尖銳的長寬比很高的位移開裂.” 裂紋通常被認為是嚴重的不連續(xù),因為在應力的作用下將會延裂紋方向延伸.通常根據(jù)裂紋出現(xiàn)的位置和出現(xiàn)的時間或者常用的使用術(shù)語進行描述；見下面的插圖：AWS裂紋術(shù)語學.(A) (B)LEGEND:1. CRATER CRACK弧坑裂紋 2.FACE C

30、RACK表面裂紋 3.HEAT-AFFECTED ZONE CRACK熱影響區(qū)裂紋 4.LAMELLAR TEAR層狀撕裂 5.LONGITUOINAL CRACK縱向裂紋 6.ROOT CRACK根部裂紋 7.ROOT SURFACE CRACK根部表面裂紋 8.THROAT CARCK焊喉裂紋 9.TOE CRACK焊趾裂紋 10.TRANSVERSE CRACK橫向裂紋 11.UNDERBEAD CRACK母才內(nèi)部裂紋 12.WELD INTERFACE CRACK焊接熔合面裂紋 13.WELD METAL CRACK 焊縫裂紋Common causes and remedies of

31、cracking 通常情況下出現(xiàn)裂紋的原因及修復Causes: weld metal joint 原因: 焊接金屬接頭Remedies: weld metal cracking 修復: 焊接金屬裂紋Highly rigid joint 高強度接點Preheat 預熱Relieve residual stresses mechanically(peening)機械去除殘余應力(錘擊)Minimize shrinkage stresses using backstep or block welding sequence采取分段退焊或者分層退焊的方法減小收縮應力Excessive dilution

32、過度稀釋Change welding current and travel speed 檢查焊接電流和運行速度Weld will covered electrode negative ;butter the joint faces prior to welding 焊接采用藥皮焊條直流反接，焊接前接頭表面堆焊Defective electrodes 焊條損壞Change to new electrode ; bake electrodes to remove moisture更換焊條,烘烤焊條去除水汽Poor fit-up 組對不當Reduce root opening ; build up

33、the edges with weld metal . increase root opening減小根部間隙;使用焊接金屬堆焊. 增大根部間隙Small weld bead 焊縫太小Increase electrode size ; raise welding current ; reduce travel speed增加焊條尺寸,增加焊接電流,降低焊接速度High sulfur base metal含硫很高的母材Use filler metal low in sulfur使用低硫填充金屬Angular distortion 角變形Change to balanced welding on

34、both sides of joint 在接頭倆邊采用對稱焊接Crater cracking弧坑裂紋Fill crater before extinguishing the arc ; use a welding current decay device when terminating the weld bead 在電弧熄滅前將弧坑填滿, 在焊接結(jié)束時使用焊接電流衰減裝置Causes : heat-affected zone原因: 熱影響區(qū)Remedies : heat-affected zone 修復: 熱影響區(qū)Hydrogen in welding atmosphere焊接環(huán)境中含氫Us

35、e low-hydrogen welding process ; preheat and hold for 2 hour after welding or postweld heat treat immediately 使用低氫焊接程序;焊前預熱并且在焊后緩冷倆小時或者立刻采用焊后熱處理Hot cracking熱裂紋Use low heat input ; deposit thin layers ; change base metal and/or filler metal 降低熱輸入;減薄層接焊道;更換母材和(或)填充金屬Low ductility延展性低Use preheat ; anne

36、al base metal prior to welding使用預熱;在焊接前母材退火處理High residual stresses很高的殘余應力Redesign weldment ; change welding sequence ; apply intermediate stress-relief heat treatment 重新設計焊接件;改變焊接次序;應用熱處理的方法消除應力High hardness高硬度Preheat : increase heat input ; heat treat without cooling to room temperature 預熱;增加熱輸入;溫

37、度不低于室溫時進行熱處理Brittle phases in the microstructure在宏觀顯微結(jié)構(gòu)下呈易碎的相圖Solution heat treat prior to welding 在焊接前通過加熱固熔退火九、Inclusions夾渣Inclusions are defined as entrapped foreign solid material , such as slag , flux , tungsten , or oxide .” The inclusions may be found as single particles , aligned particles .

38、 Slag inclusions arefrequently found on the weld surfaces , or along the toes of the weld due to improper cleaning techniques . Tungsten inclusions are usually subsurface . Examples of inclusions are shown below. Inclusions on the surface can be detected by VT ; subsurface inclusions require UT or R

39、T.Slag inclusions (darkened areas)內(nèi)部夾渣（發(fā)暗的區(qū)域）Repairs of inclusions on the surface require removal by gouging or grinding ,welding if required and reinspection by appropriate NDT method .subsurface inclusions require removal by gouging or grinding .followed by weld repair and reinspection .夾渣被定義為: “陷

40、在焊縫中的外界固體物質(zhì),比如焊渣,焊劑,鎢,或氧化物. 夾渣可能以單個顆?；蚓€形顆粒出現(xiàn). 由于清理方法的不正確夾渣經(jīng)常出現(xiàn)在焊縫表面或焊趾處。 夾鎢出現(xiàn)在焊縫內(nèi)部。在表面的夾渣可以通過目視檢查來發(fā)現(xiàn)；內(nèi)部夾渣需要通過超聲波或者X射線來檢查發(fā)現(xiàn)。表面的夾渣返修可以通過氣刨或者打磨去除，修補處如果需要可以使用適當?shù)腘DT方法來重新檢驗。焊縫內(nèi)部夾渣需要通過氣刨或打磨來去除，焊接修補并且重新檢驗。Common Causes and Remedies of Slag Inclusions通常情況下出現(xiàn)夾渣的原因及返修Causes 原因Remedies修復Failure to remove slag

41、沒有清理焊渣Clean surface and previous weld bead 在焊前清理焊道Entrapment of refractory oxides 高熔點的氧化物Power wire brush the previous weld bead 在施焊前用動力鋼絲刷清理焊道Tungsten in the weld metal 焊接金屬中含鎢Avoid contact between the electrode and the work ; use larger electrode避免電極與焊件的接觸；使用較大的電極Improper joint design 接頭設計不合理Incre

42、ase groove angle of joint 增大坡口對接角度Oxide inclusions 氧化物夾渣Provide proper gas shielding 使用正確的保護氣Slag flooding ahead of the welding arc焊渣溢流到焊接電弧的前面Reposition work to prevent loss of slag control通過重新裝配來控制焊渣的流失Poor electrode manipulative technique焊條操作技術(shù)落后Change electrode or flux to improve slag control通過更

43、換焊條或焊劑來控制焊渣Entrapped pieces of electrode covering 焊條的藥皮脫漏Use undamaged electrodes使用未損壞的焊條十、Incomplete fusion未熔合Incomplete fusion is defined as”A weld discontinuity in which fusion did not occur between weld and fusion faces or adjoining weld beads .”incomplete fusion (1F)can occur on both groove wel

44、ds and fillet welds where the weld does not extend to the joint root . see the figure below.未熔合被定義為：焊縫和坡口面或者相鄰焊縫面未發(fā)生熔合的焊接不連續(xù)。未熔合（1F）出現(xiàn)在坡口焊和填角焊中的接頭根部。見下圖：(A)（C）Detection of incomplete fusion using VT is possible if the discontinuity location is visible on the surface ; oblique angle lighting and 10 m

45、agnification aid the inspector . Generally ,1F subsurface and is found using UT or RT methods.如果未熔合明顯的在表面可以通過目視檢驗發(fā)現(xiàn)；從斜角方向用光照射或10倍放大鏡可以幫助檢驗。通常在表面以下的未熔合需要通過UT和RT來發(fā)現(xiàn)。Repairs of incomplete fusion require removal of the discontinuity by gouging or grinding , followed by weld repair and final inspection.返

46、修未熔合需要氣刨或者打磨來去除缺陷，焊接返修并且做最終檢驗。Common causes and remedies of incomplete fusion通常產(chǎn)生未熔合的原因及修復Causes原因Remedies修復Insufficient heat input , wrong type of size of electrode , improper joint design , or inadequate gas shielding熱輸入量不足，焊條型號不對，接頭設計不合理或者保護氣體不合適Follow correct welding procedure specification按照正確的

47、焊接程序施焊（WPS）Incorrect electrode position 焊條角度不正確Maintain proper electrode position 保持焊條的正確角度Weld metal running ahead of the arc焊縫金屬流到了電弧的前邊Reposition work lower current or increase weld travel speed重新裝配降低電流或者加快焊接速度Trapped oxides or slag on weld groove or weld face 焊接坡口或者焊縫表面有氧化物或者焊渣Clean weld surface

48、 prior to welding在焊接前清潔焊縫表面十一、Incomplete joint penetration未熔透Incomplete joint penetration is defined as “A joint condition in a groove weld in which weld metal does not extend through the joint thickness .”Note that it applies to groove welds only ,not filled welds . Examples of incomplete joint pen

49、etration(IJP)are shown in the following figures .未熔透被定義為：在坡口焊中焊接金屬沒有完全穿透坡口的接頭厚度。以上定義僅適應于坡口焊，填角焊不適用。未熔透實例見下圖： Incomplete joint penetration can easily be found by VT if the rood of the groove weld is visible ; oblique angle lighting assists in its detection . For groove welds with the root not visible

50、 . UT or RT are required for detection . Repairs for IJP , when access to the root of the groove weld is possible:未熔透如果發(fā)生在表面通過目視檢驗會很容易,斜角方向用光照射可以幫助發(fā)現(xiàn)缺陷。如果坡口根部不容易看見，就需要用UT或者RT來檢查。返修未熔透，當在坡口根部時：gouge or grind root to an oval , open shape , permitting access to root .氣刨或者打磨根部成橢圓型，形狀接近根部焊縫weld , followe

51、d by appropriate NDT method .焊接，并且使用適當?shù)腘DT方法來檢驗Repairs for up , where access to the root is not possible :當不能接近根部時從上面返修gouge or grind from the weld face the remove entire weld down to joint root從焊縫表面氣刨或者打磨至坡口的接頭根部weld followed by appropriate NDT method.焊接，并且使用適當?shù)腘DT方法檢驗Common causes and remedies of

52、incomplete of incomplete joint penetration通常導致未熔透的原因及修復Causes 原因Remedies修復Excessively thick root face or insufficient root opening 根部鈍邊太厚或者根部間隙不夠Use proper joint geometry使用適當?shù)慕宇^形式Insufficient heat input 熱輸入量不夠Follow welding procedure specification按WPS 焊接Slag flooding ahead of welding arc焊渣溢到焊接電弧的前面A

53、djust electrode or work position 調(diào)整電極或者焊接方向Electrode diameter too large 焊條直徑太大Use smaller electrodes in root or increase root opening 使用小直徑的焊條或者增大根部間隙Misalignment of second side weld倆邊未對準Improve visibility or backgouge 盡可能改進或者反面氣刨Failure to backgouge when specified 在對指定的區(qū)域背面氣刨失敗Back gouge to sound m

54、etal if required in welding procedure specification如果需要按照WPS 對母材深度背面氣刨Bridging or root opening 支撐或根部間隙Use wider root opening or smaller electrode in root pass增大根部間隙或者使用小直徑焊條封底焊接 十二、Overlap焊瘤Overlap is defined as “ the protrusion of weld metal beyond the weld toe or weld root .” example are shown bel

55、ow for fillet and groove welds . 焊瘤被定義為“在焊趾或焊跟處焊接金屬外溢突出?！标P于填角焊或坡口焊焊瘤事例見下圖：Detection of overlap is usually found by VT if the surface are visible to the eye ; oblique lighting and 10 x magnification are helpful . PT and MT may be require to inspect questionable areas.Repair include removal of overlap

56、 by gouging or grinding as a minimum , and may require weld repairs to the gouged or areas , followed by reinspection using appropriate NDT method.如果焊瘤明顯的在表面通常通過目視檢驗就可以發(fā)現(xiàn)，使用斜光照射或10倍放大鏡檢查是非常有用的。對可疑的區(qū)域可以通過PT和MT檢驗。返修包括通過氣刨或者打磨把焊瘤處理到最小，可能在氣刨的區(qū)域需要焊接返修，通過適當?shù)腘DT方法來重新檢驗。Common causes and remedies of overlap

57、通常產(chǎn)生焊瘤的原因及返修Causes 原因Remedies 修復Slow travel speed焊接速度太慢Increase travel speed提高焊接速度Poor electrode manipulation 焊條操作太差Additional welder training 加強焊工的培訓Gravity 重力原因Additional welder training 加強焊工的培訓十三、Porosity氣孔Porosity is defined as “cavity type discontinuities formed by gas entrapment during solidif

58、ication or in a thermal spray deposit .” The porosity may be surface or subsurface , a single cavity aligned , or clustered, and is represented by the following figures .氣孔被定義為“孔穴型不連續(xù)由于氣體在金屬凝固時或者熱量散失前沒有溢出形成的?！睔饪卓赡艽嬖谟诒砻婊蛘邇?nèi)部。下圖描述了單一的線形氣孔和密集氣孔：表面分散氣孔內(nèi)部密集氣孔Repairs of porosity consist of removal of the a

59、ffected area by gouging or grinding , weld repair, followed by reinspection by the appropriate NDT method .氣孔的返修包括通過氣刨或者打磨將受影響的區(qū)域去掉進行焊接返修，通過適當?shù)腘DT方法來重新檢驗。Common causes and remedies of porosity通常導致氣孔的原因及修復Causes 原因Remedies修復Excessive hydrogen , nitrogen , or oxygen in welding atmosphere在焊接氣體中含大量的氫、氮、

60、氧氣Use low-hydrogen welding process : filler metals high in deoxidizers ; increase shielding gas flow 使用低氫焊接工藝：含高去氧劑的填充金屬；增大保護氣體的流量High solidification rate 凝固速率太高Use preheat or increase heat input 使用焊前預熱或者增加熱輸入量。Dirty base metal母材不干凈Clean joint faces and adjacent surfaces清潔接頭面及相鄰區(qū)域Dirty filler wire 填