奧氏體不銹鋼焊接-中英對(duì)照

奧氏體不銹鋼的一般性焊接規(guī)則是盡可能使用低熱量放入焊接，以避免基材中熱影響區(qū)(HAZ)的敏化。因此要遵守以下

規(guī)則：

a. 出于敏化風(fēng)險(xiǎn)的考慮，對(duì)承包商在焊接規(guī)范中列出的焊接參數(shù)進(jìn)行篩選。

b. 層間溫度不得超過(guò)120攝氏度。

c. 不同材料的焊接，例如：碳鋼焊接至奧氏體不銹鋼時(shí)，焊接終端與合金填充材料之間最小焊縫距離為1.5mm。不允許

無(wú)填充材料的焊接。

d. 焊接修補(bǔ)的總量應(yīng)該受限制。不銹鋼304和306基材的焊接不能用于超過(guò)兩處局部修補(bǔ)。如需更多修補(bǔ)，準(zhǔn)備新的接

頭同時(shí)移開(kāi)至距熱影響區(qū)5mm處。

e. 無(wú)需預(yù)熱

f. 不允許特有大型號(hào)的電極。

特別注意接頭準(zhǔn)備和不銹鋼處理的工作。不銹鋼表面必須無(wú)低碳鋼或其他有害材料的污染。所有的卡扣、臨時(shí)附加裝

置、墊板、插腳，隔斷及吊環(huán)等都必須采用不銹鋼制作或鍍不銹鋼。工具和研磨盤(pán)必須適用于不銹鋼材料。不銹鋼不

得直接接觸低碳鋼。

使用不銹鋼刷及時(shí)處理或清潔不銹鋼焊接處并鈍化。

12 射線照相檢查

承包商采取射線照相檢查焊接接頭。

在必要的熱處理之后進(jìn)行檢查。

根據(jù)國(guó)際焊接人員培訓(xùn)與資格認(rèn)證體系IIW中“焊接參考射線照片的收集”來(lái)評(píng)估薄膜情況。綠色度應(yīng)達(dá)到國(guó)際焊接人員

培訓(xùn)與資格認(rèn)證體系3 的要求且無(wú)根部無(wú)缺陷。

如果檢查因承包商的緣故須重復(fù)第二次，承包商應(yīng)支付重復(fù)檢查的費(fèi)用。

13 管制當(dāng)局

除非經(jīng)買(mǎi)方批準(zhǔn)，否則在任何經(jīng)測(cè)試與驗(yàn)證合格的容器或管路系統(tǒng)上焊接將是不被允許的。

承包商在任何經(jīng)測(cè)試與驗(yàn)證合格的壓力容器或管路系統(tǒng)上進(jìn)行焊接，必須使用合格的焊接工，并對(duì)全部檢驗(yàn)，測(cè)試與

重新驗(yàn)證以及管制當(dāng)局和/買(mǎi)方要求的費(fèi)用負(fù)責(zé)。

14 測(cè)試與抽樣

無(wú)論何種情況下，管制當(dāng)局和/或買(mǎi)方一旦提出要求，承包商都應(yīng)按買(mǎi)方和/或管制當(dāng)局提出針對(duì)不同材料和工藝樣品，

以及工程中指定使用或即將使用的制成品的要求交樣件給他們審批。

15 焊接修補(bǔ)

焊接錯(cuò)誤的更正應(yīng)完全讓買(mǎi)方滿意。所有的修補(bǔ)和額外檢驗(yàn)的費(fèi)用都應(yīng)由承包商承擔(dān)。

16 防腐蝕處理，修補(bǔ)涂裝

在完成焊接工作并通過(guò)買(mǎi)方批準(zhǔn)后，承包商應(yīng)履行或補(bǔ)充表面處理。
WELDING OF AUSTENITIC STAINLESS STEEL
 
As a general rule austenitic stainless steel shall be welded with as low heat input as possible to avoid sensitizing of the heat

affected zone (HAZ) in the base material. Therefore the following rules shall apply:

a. The welding parameters in the Welding Specifications worked out by the Contractor shall be selected due to the risk of

sensitizing.

b. The inter-pass temperature shall not exceed 120 deg. C

c. The welding of dissimilar materials, e.g. carbon steel to austenitic stainless steel shall be performed with a minimum gap of 1.5

mm between the weld ends and with over alloyed filler material. Welding without filler material is not permitted.

d. The amount of weld repairs shall be limited. Welds of AISI 304 and 316 base materials may not be subject to more than two

local repairs. If more repairs are required, a new joint preparation must be carried out removing the HAZ-material within 5 mm.

e. No preheating is allowed

f.  Oversized electrodes are not permitted

Special attention shall be paid to the joint preparation and handling of stainless steel. The stainless surface must be prevented

from contamination of mild steel or other harmful materials. All clips, temporary attachments, strong back, bull pins, spacers,

lifting lugs etc. must be of stainless steel or plated with stainless steel. The tools, grinding discs etc. must be well adapted for

working with stainless steel. The stainless steel must never come directly into contact with mild steel.

Stainless steel welds shall immediately be pickled, cleaned mechanically with a stainless steel brush and passivated.

12 RADIOGRAPHIC EXAMINATION

The Contractor carry out radiographic tests on welded joints.

The examination shall be performed after necessary heat treatments.

The films shall be evaluated in accordance with the IIW "Collection of Reference Radiographs of Welds". The requirement is

Degree Green (IIW 3) without any root defects.

If the examination is repeated for second times due to the faults by the Contractor, the Contractor shall pay the repeated

examination.

13 REGULATING AUTHORITIES

Welding on any tested and certified pressure vessel or piping system shall not be permitted unless specifically approved by the

Purchaser.

Where welding is carried out by the Contractor on any tested and certified pressure vessel or piping system, the Contractor shall

use certified welders and shall be responsible for all inspection, testing, recertification, and fees as required by the Regulating

Authorities and/or the Purchaser.

14 TESTING AND SAMPLING

Whenever so requested by the Purchaser and/or Regulating Authorities the Contractor shall submit for approval such samples as

the Purchaser and/or Regulating Authorities may require of the various materials, together with specimens of workmanship and

finish thereof, specified for, and intended to be used in the work.

15 REPAIR OF WELDS

The correction of weld faults shall be carried out to the entire satisfaction of the Purchaser. All costs of repairs and extended

examinations shall be carried out at the expense of the Contractor.

16 ANTI-CORROSION TREATMENT, TOUCH UP PAINTING

After the welding work is completed and accepted by the Purchaser, the Contractor shall perform or touch up the surface

treatment.

2014.8.12