Методичка по сварке (778485), страница 5

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2.15 Terminological vocabulary to the text “Single-V Groove Butt Joint Welds”. Try to memorize the following words and word combinations.

1. in the neighbourhood [0neibQhud] of – приблизительно;

2. assembly [Q0sembli], n – сборка;

3. to cause [kOz], v – вызывать, быть причиной;

4. to turn over, v – переворачивать;

5. to retain [ri0tein], v – удерживать, сохранять;

6. a support [sQ0pOt], n - суппорт; снабжение;

7. slightly [0slaitli], adv – немного, слегка;

8. bevelling – скашивание кромки, разделка кромок;

9. reasonable [0rIz(Q)nQbl], adj – обоснованный;

10. fit-up, n – сборка, соединение под сварку;

11. to tolerate [0tol(Q)reit], v – допускать;

12. to accommodate [Q0komQdeit], v – приспосабливать(ся);

13. to shift, v – передвигать(ся);

14. acceptable [Qk0septQbl], adj – приемлемый;

15. an objection [Qb0dGekS(Q)n], n – возражение.

Word Study

2.16 Read the words correctly. Consult the dictionary if necessary.

Neighbourhood, advantages, variations, simplify, voltage, penetration, considerably, fusible, ensure, permissible, bevelling.

2.17 Translate the following words into Russian paying attention to the underlined prefixes :

Misalignment, independent, disassembly, refuse, unbend, imperfect, misconnection, indissoluble, non-fusible, unfluxible, disconnection, impermeable, nonconsumable, indiffusible, disassociation, nonhardenable, uncoated, retest, rewelding, imporosity, discontinuity, nonmagnetic, ungrease, restrike, reprecipitation, disintegration, uncombined, removal, impure, unload, inexplosive, nonporous, dissociate, unshielded.

2.18 Translate the following sentences into Russian paying attention to the underlined words:

1. This joint type is to be used with non-fusible backing for single-pass butt welds of 5/16-in. or greater thickness. 2. For most industrial applications, the maximum thickness is to be in the neighbourhood of 1-1/4 to 1-1/2-in. 3. The purpose of the finishing weld is to ensure a continuous weld structure throughout the plate thickness. 4. Relatively small quantities of wire are to be used because V preparation gives the desired penetration. 5. Fusible metallic backing is to be used with this preparation with a root gap of at least 1/8-in. 6. The weld metal is to be fused to the backing piece. 7. The backing is to be non-fusible to provide the root face dimension in the range from 1/8 to 3/16-in. 8. The mass of metal at the joint root is not sufficient to provide weld metal support. 9. A satisfactory method of getting the required penetration of the finishing weld without excessive reinforcement is to back gouge a groove 1/8 in. deep. 10. Copper backing is not to be used because of the tendency of the weld metal to fuse to the backing piece.

2.19 Fill in the gaps with the necessary prepositions.

2.20 Right or wrong?

1. Single-V Groove without Root Face is used with non-fusible backing for single-pass butt welds of 5/16-in. or greater thickness. 2. When using Single-V Groove with Root Face the maximum thickness of the plate is in the neighbourhood of 1-1/4 to 1-1/2-in. 3. The single-V groove butt joint with root face and without external backing is used for two pass welds where plate thickness exceeds 5/8-in. 4. With fusible backing, the root face dimension is 1/8 to 3/16-in. 5. With non-fusible backing, the root face dimension is 1/8 to 3/16-sm. 6. The finishing weld penetrates down into and refuses a portion of the backing weld to ensure complete penetration. 7. The plate edges must be tightly butted (1/16-in. maximum gap) as with the square butt joint. 8. The single-v groove without root face is commonly used for nearly all thicknesses when using submerged arc backing flux. 9. The single-v groove without root face is commonly used below 3/8-in. thickness since adequate penetration can be obtained for these thicknesses without bevelling. 10. Titanium backing is not recommended because of the tendency of the weld metal to fuse to the backing piece.

2.21 Read the text paying attention to the active terminological vocabulary to check if your predictions were correct.

Groove Butt Joint Welds (2843 п. зн.)

D ouble-V Groove Butt Joint is the basic joint design for two-pass submerged arc welds. It is commonly used for thickness up to 2-in., and even greater thicknesses have been welded successfully. For thicknesses above 2-in., however, the joint for multipass welding is recommended. The double-v groove joint is normally designed with a large root face to provide adequate support for the initial weld which serves as backing for the weld from the opposite side. The maximum possible misalignment in fit-up is 25 per cent of the root face. The root faces must be closely butted along their entire length. The maximum permissible root gap is 1/32-in. If the root gap is larger the flow of material through the gap, when making the

initial weld, must be prevented. Several methods are used. A small stringer bead can be laid manually in the bottom of the v in which the finishing weld is to be made. A length of wire may be tacked into the finishing weld. Submerged arc backing flux may be tamped into the gap ahead of the weld. The stringer bead, wire, or backing flux should be removed before making the finishing joint if a high-quality joint is required. To ensure 100-per cent penetration and the removal of any slag or porosity in the bottom of the backing weld, the finishing weld should penetrate into and refuse the backing weld to a depth of 3/16 to 5/16-in. Since this joint is widely used in pressure vessel fabrication, one limitation should be noted. When making circumferential welds, the ratio of joint thickness to cylinder diameter must be at least 1/25. Otherwise, the large pool of molten metal will tend to run, c ausing unstable welding action and undesirable weld shape. Manual weld backing is sometimes used with the double-v groove butt joint when the joint has a small (1/8-in. maximum) root face and a root gap of about 1/8-in. If conditions require that the manual weld be thicker than 3/8-in., however, the single-V and U groove butt joint is preferred.

The Single-U Groove Butt Joint is often used for multipass submerged arc welds. Any thickness of material can be welded using this joint design. A small manual backing weld is often made from the reverse side of the joint. If the manual weld is not made, the root faces must be closely butted (1/32-in. maximum root gap). For extremely thick material, double-U groove butt joints may be used. These are essentially two single-U groove butt joints with a common root. If a manual weld is used to back the first submerged arc weld pass, it may be desirable to remove it later if maximum quality is required. The use of gas metal-arc manual welds eliminates the need for removal prior to submerged arc welding. Because of the internal and external slag-free nature of gas metal arc deposits, subsequent submerged arc welds of excellent quality can be produced over them.

From (http://www.esabna.com/EUWeb/SA_handbook/585sa2_28.htm)

2.22 Terminological vocabulary to the text “Groove Butt Joint Welds”. Try to

memorize the following words and word combinations.

1. Single-V Groove( butt) - V-образная разделка( стыкового соединения) со скосом двух кромок;

2. Single-U Groove( butt) - V-образная разделка( стыкового соединения) с одним криволинейным скосом двух кромок;

3. Double-V Groove( butt) - Х-образная разделка( стыкового соединения) с двумя( симметричными) скосами двух кромок;

4. Double-U Groove( butt) – Х-образная разделка( стыкового соединения) с двумя криволинейными скосами двух кромок;

5. stringer bead – валик, наплавленный без поперечных колебаний электрода, горелки;

6. to tack – сваривать прихваточным швом;

7. initial [i0niS(Q)l], adj – начальный, исходный;

8. backing weld – подварочный шов;

9. circumferential [sQ4kqmf(Q)0ren(t)S(Q)l]weld – кольцевой (круговой) шов;

10. pressure vessel – сосуд высокого давления, автоклав.

Word Study

2.23 Read the words correctly. Consult the dictionary if necessary.

reinforcement, approximately, misalignment, bevelling, relatively, subsequent, successfully, neighbourhood.

2.24 Pick out in the text all the expressions with the following words and give their Russian equivalents. Make up sentences of your own with these expressions.

root; joint; backing; groove; thickness.

2.25 Translate the following word combinations into Russian.

single-pass butt welds; relatively small quantities; desired penetration without excessive current; square groove butt joint without root opening; the basic joint design; excessive reinforcement; for most industrial applications; the internal and external slag-free nature of gas metal arc deposits; subsequent submerged arc welds of excellent quality; maximum permissible root gap.

2.26 Make up and practise short situations using the following words and word combinations.

1. weld reinforcement, flowing through the root opening, weld backing, reverse side of the joint;

2. root face, non-fusible backing, minimum damage to the backing;

3. adequate penetration, without bevelling, reasonable misalignment;

4. multipass welding, large root face, initial weld, several methods are used;

5. manual backing weld, from the reverse side of the joint, need for removal.

2.27 Make up dialogues using the word expressions of Ex. 9.26

2.28 Put the verbs in brackets into the necessary form (Active or Passive). Translate the following sentences into Russian paying attention to the underlined words:

1. Any thickness of material can … (to weld) using this joint design. 2. The root faces must … closely (to butt) along their entire length. 3. The single-v groove butt joint without root face must always… (to have) weld backing. 4. The stringer bead, wire, or backing flux should … (to remove) before making the finishing joint if a high-quality joint is required. 5. A small stringer bead can … (to lay) manually in the bottom of the v in which the finishing weld is … (to make). 6. Root gap should not … (to exceed) 1/16-in. 7. For extremely thick material, double-U groove butt joints may … (to use). 8. Weld reinforcement, which tends to become excessive for thicker welds, can … (to control) by adjusting the root opening. 9. When the root opening exceeds 1/16-in., however, the opening should … closely (to fill) with submerged arc welding flux ahead of the weld. 10. For instance, the 1G position weld refers to a groove weld that is … (to make) in the flat position. 11. It is important that you have a good understanding and can … (to apply) the techniques for welding in each of the test positions.

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