CN110238494A - A kind of mechanical welding procedure of boiler tube panel high-alloy steel - Google Patents

Abstract

A kind of mechanical welding procedure of boiler tube panel high-alloy steel, comprising the following steps: 1) preheating before welding: 2) adjust the relative position of fin and pipe: 3) welding parameter: 4) slow cooling after welding.The present invention, pass through the analysis of welding performance and influence factor to the material, welding equipment is adjusted and is improved, the change of pre-heating mean, increases the measures such as postwelding is slow, solve SA213-T91 material welding performance is poor, temperature susceplibility by force, postwelding be also easy to produce the problems such as crackle.The effective measures for guaranteeing the high weld seam of the intensive quality of high-volume, improve 30% or more primary production yields, substantially increase the market competitiveness of enterprise.

Description

A kind of mechanical welding procedure of boiler tube panel high-alloy steel

Technical field

The present invention relates to water-tube boiler technology fields, more particularly to a kind of T91 high alloy for boiler tube panel The fillet weld Anti-cracking welding procedure of steel pipe.

Background technique

With international energy more come less and energy consumption give environment bring influence, make people to the coal-fired power project thermal efficiency, The requirements such as low-carbon emission, nuisance control are also maked rapid progress；For this purpose, root equally has occurred in the technical performance and parameter of coal electricity at present This variation, the requirement such as large-sized unit, large capacity, high-performance, high efficiency, low emission force coal unit high parameter, low emission Index is constantly updated, and high-grade material such as SA213-T91 etc. especially in boiler has been largely used to boiler heating surface tube panel, but The high-alloy steel weldability such as t91 is poor, and alloying element therein is high, and contains strong carbonization elements, if weld preheating is bad, postwelding Easily there is hot cracking tendency, and using continuous multi-pass welding in mechanical welding process, interlayer temperature easily occur it is excessively high,

Great challenge is brought to tube panel manufacture difficulty, material welding performance is poor, temperature sensitivity is strong, postwelding is easy to produce crackle The features such as.

Summary of the invention

Aiming at the problem that mentioned above come out, the purpose of the present invention is to provide a kind of T91 high conjunctions for boiler tube panel The fillet weld Anti-cracking welding procedure of golden steel pipe passes through relative position and the increase for improving pre-heating mean, adjusting fin and pipe Retarded cooling process after welding, to achieve the purpose that improve welding quality.

The technical scheme is that realized by following technique: a kind of mechanical welding of boiler tube panel high-alloy steel Technique, comprising the following steps:

1), preheating before welding: using two-sided preheating, extends preheated zone and increases hot spot quantity, wherein SA387Cr91CL2 When band steel and (SA213-T91) pipe of Φ 70 × 6 use submerged arc welding, preheating temperature is 200 DEG C；SA387Cr91CL2 band steel When carrying out fillet welding using argon arc welding with (SA213-T91) pipe of Φ 70 × 6, preheating temperature is 200 DEG C；

2) relative position of fin and pipe, is adjusted:

(1) it is composed and laid out fin upright position when assembled by control fin and pipe, it is ensured that fin center and tube center are kept In same level；

(2) by adjusting the top pier power of pinch wheels, under the premise of guaranteeing tube panel pitch, it is ensured that pipe and fin are adjacent to journey Degree；

(3) by puck position above and below adjusting, guarantee under the premise of pipe and fin are adjacent to, it is smooth up and down；

3), welding parameter: when SA387Cr91CL2 band steel and (SA213-T91) pipe of Φ 70 × 6 use submerged arc welding, welding Material uses MTS-3- Φ 1.6,27~28V of weldingvoltage, 240~270A of welding current；SA387Cr91CL2 band steel and Φ 70 × 6 (SA213-T91) pipes using argon arc welding carry out fillet welding when, welding material use MTS-3- Φ 2.4, weldingvoltage 13~ 18V, 90~130A of welding current；

4) slow cooling after, welding: by covering asbestos simultaneously up and down away from section of jurisdiction and big row away from/more piece to single-unit, holding temperature is controlled Between 300-400 DEG C, soaking time 2 hours or more, slow cooling is kept the temperature in time to postwelding weld seam in this way, it is ensured that two side welds are received Contracting is uniform consistent.

The present invention adjusts welding equipment and improves, is pre- by the analysis of welding performance and influence factor to the material The change of hot method increases the measures such as postwelding is slow, solve SA213-T91 material welding performance is poor, temperature susceplibility by force, postwelding It is also easy to produce the problems such as crackle.The effective measures for guaranteeing the high weld seam of the intensive quality of high-volume, improve primary production yields 30% or more, substantially increase the market competitiveness of enterprise.

Detailed description of the invention

Fig. 1 is fin of the present invention and pipe location diagram.

In figure: 1 pipe, 2 fins, 3 upper pressure wheels, 4 lower pressure wheels.

Specific embodiment

The technical scheme is that realized by following technique:

1, preheating before welding: using two-sided preheating, extends preheated zone and increases hot spot quantity, wherein SA387Cr91CL2 is flat When steel and (SA213-T91) pipe of Φ 70 × 6 use submerged arc welding, preheating temperature is 200 DEG C；SA387Cr91CL2 band steel with When (SA213-T91) pipe of Φ 70 × 6 carries out fillet welding using argon arc welding, preheating temperature is 200 DEG C.

2, it adjusts the relative position of fin 2 and pipe 1: being known by Fig. 1,

1) it is composed and laid out 2 upright position of fin when assembled by control fin 2 and pipe 1, it is ensured that 2 center of fin and 1 center of pipe Be maintained in same level, it is therefore prevented that because position deviation is excessive cause to take the photograph heat is uneven, heat transfer is uneven and postwelding shrink it is different The phenomenon that cause；

2) by adjusting the top pier power of pinch wheels, under the premise of guaranteeing tube panel pitch, it is ensured that pipe and fin are adjacent to journey Degree, welding is steady when ensure that welding, even weld, heat transmitting are consistent and uniformly；

3) by adjusting upper pressure wheel 3 and 4 position of lower pressure wheel, guarantee under the premise of pipe 1 and fin 2 are adjacent to, up and down it is smooth (i.e. The inclination of fin is controlled, and guarantees the flatness of tube panel).

3, welding parameter: when SA387Cr91CL2 band steel and (SA213-T91) pipe of Φ 70 × 6 use submerged arc welding, Welding material uses MTS-3- Φ 1.6,27~28V of weldingvoltage, 240~270A of welding current；SA387Cr91CL2 band steel with When (SA213-T91) pipe of Φ 70 × 6 carries out fillet welding using argon arc welding, welding material uses MTS-3- Φ 2.4, weldingvoltage 13 ~18V, 90~130A of welding current.

4, slow cooling after welding: by covering asbestos, control heat preservation temperature simultaneously up and down away from section of jurisdiction and big row away from/more piece to single-unit Degree soaking time 2 hours or more, keeps the temperature slow cooling to postwelding weld seam in this way, it is ensured that two side welds between 300-400 DEG C in time It shrinks uniform consistent.By increasing postheating measure, slow down weld seam because take the photograph heat it is excessive caused by radiate it is too fast, cooling terraced While spending big, reduce weld contraction deflection, also avoids the generation of weld crack.

By the analysis of welding performance and influence factor to the material, welding equipment is adjusted and is improved, pre-heating mean Change, increase the measures such as postwelding is slow, solve SA213-T91 material welding performance is poor, temperature susceplibility by force, postwelding is also easy to produce The problems such as crackle.The effective measures for guaranteeing the high weld seam of the intensive quality of high-volume, improve primary production yields 30% with On, substantially increase the market competitiveness of enterprise.

Claims (1)

1. a kind of mechanical welding procedure of boiler tube panel high-alloy steel, comprising the following steps:

1), preheating before welding: using two-sided preheating, extends preheated zone and increases hot spot quantity, wherein SA387Cr91CL2 When band steel and (SA213-T91) pipe of Φ 70 × 6 use submerged arc welding, preheating temperature is 200 DEG C；SA387Cr91CL2 band steel When carrying out fillet welding using argon arc welding with (SA213-T91) pipe of Φ 70 × 6, preheating temperature is 200 DEG C；

2) relative position of fin and pipe, is adjusted:

(1) it is composed and laid out fin upright position when assembled by control fin and pipe, it is ensured that fin center and tube center are kept In same level；

(2) by adjusting the top pier power of pinch wheels, under the premise of guaranteeing tube panel pitch, it is ensured that pipe and fin are adjacent to journey Degree；

(3) by puck position above and below adjusting, guarantee under the premise of pipe and fin are adjacent to, it is smooth up and down；

3), welding parameter: when SA387Cr91CL2 band steel and (SA213-T91) pipe of Φ 70 × 6 use submerged arc welding, welding Material uses MTS-3- Φ 1.6,27~28V of weldingvoltage, 240~270A of welding current；SA387Cr91CL2 band steel and Φ 70 × 6 (SA213-T91) pipes using argon arc welding carry out fillet welding when, welding material use MTS-3- Φ 2.4, weldingvoltage 13~ 18V, 90~130A of welding current；

4) slow cooling after, welding: by covering asbestos simultaneously up and down away from section of jurisdiction and big row away from/more piece to single-unit, holding temperature is controlled Between 300-400 DEG C, soaking time 2 hours or more, slow cooling is kept the temperature in time to postwelding weld seam in this way, it is ensured that two side welds are received Contracting is uniform consistent.