工程焊縫要求翻譯-中英
5)根焊道起弧點保證熔透,根焊道內成型均勻凸起。填充層層數符合要求,填充焊道距管外表面1-2mm,蓋面前可根據填充情況在立焊部位增加立填焊。焊接時,焊條或焊絲不宜擺動太大,對較寬的焊道采用多道焊方法排焊。
(16)焊接過程中,保證流水作業各焊接工作緊密銜接,各層焊道連續焊接,確保層間溫度達到工藝規程要求。
(17)焊接過程中,焊工作好所焊焊道的自檢、修補。焊接完成后,焊工將焊縫表面的熔渣、飛濺等,清理干凈。
(18)焊工將焊條頭、焊絲段、焊絲盤等工業垃圾放入回收桶內,集中處理。
(19)組對焊接起始站以及下班或中止焊接2h以上時,組焊末端要用管帽封堵管口,但管帽不允許與管子點焊。管帽具備防止泥水進入管內的功能。下溝后的管段,同樣采用管帽封堵管子兩端。
(20)在下列任何一種焊接環境下,若無有效的防護措施,嚴禁施焊:
a)雨、雪天氣;
b)大氣相對濕度大于90%;
c)環境溫度低于焊接工藝規程規定的溫度(低于5℃);
d)手工焊時風速大于5m/s;氣體保護焊時風速大于2m/s;
(21) 對焊接環境采取保護措施如下:
a)手工、半自動焊施焊時采用簡易防風棚;
b)根焊焊接時,管線兩端管口必須封堵,已焊接管段一端采用易拆卸的封堵封死,組對焊接管端用帆布管套封堵,防止管內產生穿堂風,影響焊接質量。
c)在防風棚內裝設換風扇、除濕機和加熱裝置,降低防風棚內空氣濕度;
d)焊接環境溫度低于焊接工藝規程規定的溫度時,每層焊道焊后立即用石棉保溫被(玻璃棉或雜毛氈)對焊接接頭包裹緩冷,降低焊縫冷卻速度。
(22)當日不能完成的焊口,必須完成50%鋼管壁厚并不少于三層焊道,未完成的焊口采用干燥、防水、隔熱的材料覆蓋好。
(23)每個焊完的焊口,在氣流方向上方距焊口100mm處標出施焊焊工的代號,并填寫記錄,不采用鋼印做標記。
2)焊縫檢驗
(1)外觀檢查
管口焊接、修補或返修完成后,及時進行外觀檢查,檢查前清凈接頭表面熔渣、飛濺物和其它污物。檢查首先自檢(包括焊工自檢、機組質檢員專檢)后由現場監理復檢合格。
外觀檢查采用目測、卷尺、焊接檢驗尺。
專職檢查人員有一定焊接經驗和技術水平,具有資格證書;
本工程焊縫要達到以下外觀質量標準:
a)焊縫及其附近表面上無焊渣、無飛濺、無裂紋、未熔合、氣孔、夾渣、引弧痕跡、有害焊瘤、凹坑及夾具焊點等缺陷。
b)焊縫外觀成形均勻一致,焊縫表面不低于母材表面,焊縫余高0.5-1.6mm,余高超過時,進行打磨,打磨后與母材圓滑過渡,不傷及母材。
c)焊后錯邊量:不大于1.6mm。
d)焊縫寬度比外表面坡口寬度每側增加0.5mm~3.0mm。
e)咬邊深度不超過0.5mm;咬邊深度小于0.3mm的任何長度均為合格;咬邊深度在0.3~0.5mm之間,單個長度不超過30mm,累計長度不大于焊縫周長的15%。
(2)無損檢測
本工程管道焊接的無損檢測要求跟據設計要求和現行國家標準《現場設備、工業管道焊接工程及驗收規范》GB50236-98中關于無損檢測的要求,對管道焊縫(包括地下室中壓和其它設計要求的管線)進行30%射線無損拍片,對過路部分管道焊口進行100%的X射線檢測,Ⅱ級為合格,執行標準為GB/T12605-90。低壓燃氣管道焊接連接的所有焊縫隨機抽不少于總數的15%進行射線探傷檢查,其質量不得低于《鋼管環焊縫熔化焊對接接頭射線照透工藝和質量分級》中對II片質量要求。
7. Flange connection
1) The flange shall be carried out visual inspection before installation, and conform to following requirements:
(1) Flange nominal pressure shall conform to the design requirements.
(2) The sealing surface of flange shall be smooth and clean, and free from burrs and radial grooves. The threaded portion of flange shall be complete without any damage. The convex surface of flange shall be naturally coupled; the height of the convex shall not be lower than groove depth.
(3) The threads of bolts and nuts shall be completed and free from burrs and other defects; bolts and nuts shall be in well fit and free from the phenomenon of any loose or jam.
2) Flanges and piping sets shall conform to the following requirements:
Flange end face shall be perpendicular to the centerline of the pipeline; the deviation can be checked with square and ruler; when the nominal diameter of pipeline is smaller than or equal to 300turn, the allowable variation is about 1mm; when the nominal diameter of pipeline is larger than 300mm, the allowable variation shall be 2rmn.
3) The flange shall be installed and connected in a free status, and shall conform to the following requirements:
(1) The flange connection shall be in parallel position, the deviation shall not be greater than 1.5 ‰ of flange diameter, and shall not exceed 2mm. It is prohibited to apply the method of tightening the bolt to eliminate the deflection.
(2) The flange connection shall be in the same axis; the deviation of screw pore center shall not exceed 5%, and ensure that bolts can get into hole without hammering.
(3) The flange gasket shall conform to the relevant standard; do not use the ramp pads or double gasket. When using the soft cushion, the edges shall be neat; the pad size shall be consistent with the sealing surface of flange.
(4) Bolt and screw diameter shall be set uniform, and use the bolts with same specification and installed in the same direction; fasten the bolt with moderate force; the exposed length of bolts after fastening shall not be exceed 1 times of the length of the screw pitch, and shall not lower than the nut.
(5) The bolts after tightening shall be close to the flange, and free from seam wedge. The gasket of each bolt on each side shall not be more than 1 gasket.
4) The distant from flange to bracket edge or wall shall not less than 200mm.
5) When directly buried flange, apply the preservative measures with the same level for the flanges of pipeline and fasteners.
8. Pipeline backfill earth
(1) General control measures
A. Before starting of backfilling of pipeline, report the special position of the pipeline backfill of construction project to resident supervising engineer for approval; clarify the construction scheme, technical measures and backfill quality assurance system and report for approval before construction;
3014.4.2