CN1053205A

CN1053205A - Use common (T506) welding rod soldering ironcasting

Info

Publication number: CN1053205A
Application number: CN 90106355
Authority: CN
Inventors: 赵传武
Original assignee: Angang Steel Co Ltd
Current assignee: Angang Steel Co Ltd
Priority date: 1990-08-24
Filing date: 1990-08-24
Publication date: 1991-07-24

Abstract

A kind of common welding rod-(T506 welding rod) that relates to the iron weld repair application, it replaces electrode for cast iron, soldering ironcasting effectively, the weld bond place adopts multilayer welding, multi-pass welding, and every layer is adopted dispersion weldering, the short welding bead of discontinuous welding, welding repair process need not special heater, saves a large amount of energy; And can reduce cost 120 yuan/1kg of electrode for cast iron, 4 yuan/1kg of common welding rod significantly; Common welding rod is lower by 1.88% than casting (308) phosphorus content, and desulfurization, dephosphorization effect height are avoided bead crack; Welding procedure is simple, shortens welding interval, promotes the two increases and two cutbacks motion.

Description

Use common (T506) welding rod soldering ironcasting

A kind of common (T506) welding rod that relates to the iron weld repair application.

In modern industry is produced, foundry goods is often scrapped because of defectives such as sand holes, shrinkage cavity, crackle occurring, repair method commonly used at present is to use electrode for cast iron soldering ironcasting, need defective equipment is dismantled, put into and give 500～700 ℃ of heat in the stove of special setting, under this temperature, carry out soldering, be called casting iron hot-weld (or half hot weld) method, this method is owing to need special heater to give heat, general small enterprise does not satisfy the requirements, moreover the special complexity of electrode for cast iron technology, waste energy, therefore how not adopt.

Another method is to adopt the cold welding method welding ironcasting of nickel-base welding rod (casting 308), but nickel-base welding rod is very expensive, per kilogram needs 120 yuan, at high temperature red heat state the very low temperature range of one plasticity is arranged at welding medium cast iron weld seam, if stay the time long in that this temperature range is left alone without help, then easily produce white structure, fire check appears, can not guarantee the weldment quality, this point is particularly remarkable in the weld metal performance of nickel-base welding rod.

The weld metal penetration ratio is very important in the welding process, ironcasting carbon containing, sulphur, phosphorus amount are higher, it is just bigger to produce white structure and hot cracking tendency, casting (308) welding rod meeting carbon amount is 2%, be the strong reducing property graphite-based cover, when cooled off rapidly in the welding place, weld seam and base metal interface produced white structure, this spoken parts in traditional operas zone has very big fragility and hardness, impels the welding point place to produce fragility and crackle.

The purpose of this invention is to provide a kind of application common welding rod (T506)-alkaline low-hydrogen type welding rod and replace electrode for cast iron (casting 308); It is the soldering ironcasting effectively, not limited by production environment, need not give heat by special heater, and the salvaging casting quality is better than casting (308).

Invention is achieved in that

Only need be with common (T506) hydrogen controlled electrode to salvaging casting, adopt the touring segmentation dot welding method of even number to give heat after, apply one deck sodium carbonate at the weld bond place and weld and get final product.

Welding rod mechanism that welding process has been adopted common (T506):

T506 welding rod carbon containing only is 0.12% in a large number, is the alkaline low-hydrogen type welding rod from coating, mainly is calcium carbonate ore deposit (marble or coal stone) and fluorite, and its suitable welding sulfur-bearing, the foundry goods that the phosphorus amount is high are analyzed from the desulphurization reaction formula:

Basicity Yu is big, and desulfurization is more complete, and effect better.

From the slag dephosphorisation reaction, find out, the big I of the affinity of phosphorous acid anhydride be arranged as (affinity big come back) following formula according to oxide:

From top formula analysis: have only basic clinker to be combined into stable compound with phosphorous acid anhydride, thereby phosphorus is removed from metal, so using common (T506) welding rod takes temperature from carbon containing, can improve the penetration ratio of weld metal, see that from the coating raw material effect of basic electrode desulfurization, dephosphorization all is better than electrode for cast iron.

Common (T506) welding rod is as follows than casting (308) welding rod soldering ironcasting advantage:

1, common (T506) welding rod need not special heater, saves a large amount of energy.

2, common welding rod need be with 4 yuan/1kg, and casts 120 yuan/1kg of (308) welding rod, can reduce cost significantly, to medium-sized and small enterprises as cutting down a factory, annual 100000 yuan of the welding rod expenses of purchasing of approximately saving in water pump works.

3, common (T506) welding rod phosphorus content is 0.12%, (casting (308) phosphorus content 2%), and lower by 1.88% than casting (308) phosphorus content, the desulfurization dephosphorization effect is higher than casting (308), avoids bead crack;

4, common (T506) but all-position welding is not subjected to environmental limitations, welding procedure is simple, reduces labour intensity, shortens welding interval, increases equipment operation power, promotes the two increases and two cutbacks motion.

Use the method for common welding rod soldering ironcasting (comprising spheroidal graphite cast-iron and grey casting)

1, prepare before the weldering:

Select common welding rod spare-T506 hydrogen controlled electrode for use, core diameter 4mm, welding current intensity 160-170A, it is stand-by after 1-2 hour to be placed on 250 ℃～350 ℃ drying box oven dry.

2, selecting floating voltage for use is the above ac arc wedling machine (selecting DC arc welder to carry out reversal connection) of 70V, is placed on room temperature in the factory building, and as at outdoor calm, no rain, fine day, scene temperature does not have humidity on every side more than 10 ℃.

3, give heat:

At first use common welding rod (T506) hydrogen controlled electrode) given heat to carrying out spot welding around the salvaging casting, it gives by the use of thermal means is that the touring segmentation dot welding method of even number gives heat: adopt the touring heating of even number symmetry to give heat to spot welding place of round salvaging casting; Take the segment equalization heating to give heat to straight line or curve salvaging casting, can reduce the weldment internal stress like this, also remove foreign material such as oil, mud, rust, lacquer simultaneously, prevent from welding, to produce defectives such as slag inclusion, pore.

4, welding:

Apply the industrial sodium carbonate of one deck white powdery to giving hot-cast part weld bond place, can further improve basicity, increase is taken off, the effect of phosphorus, welds with the T506 welding rod then, weld seam is not limited by penetration ratio in the welding process, adopt multilayer welding, multi-pass welding, every layer is adopted the short welding bead that disperses weldering, disconnected weldering, wants layering, shunting to apply one deck sodium carbonate simultaneously, general welding bead is 10-30mm, postwelding carries out the hammering workpiece immediately, reduces welding stress, prevents crackle.

5, slow cooling, windproof, moistureproof.

Foundry goods after the welding carries out nature cooling, and is windproof, after moistureproof 2 hours, can work.

Embodiment: to the soldering of 250PNI slush pump (spheroidal graphite cast-iron) foundry goods.

The 250PNI slush pump, material is QT45-5, selects the soldering of common (T506) welding rod for use, and (long approximately 300mm) places the vertical position of welding with pump case outlet(discharge) flange breakage, adopts the segment equalization heating to give heat, and the about 50 ° of U type grooves of groove are advisable with through welding.Giving weld bond place after the heat applies one deck sodium carbonate and welds, multilayer welding, multi-pass welding are adopted in welding, every layer is adopted dispersion weldering, discontinuous welding will apply one deck sodium carbonate simultaneously, postwelding is the hammering workpiece immediately, and natural then slow cooling, windproof, stand-by after moistureproof 2 hours is welded outer QT45-5 foundry goods (long 300mm) and only needed one kilogram of common welding rod, 4 yuans, the shortening cycle reduces cost, and the welding technology index is higher than casting (308).

Claims

1, a kind of common welding rod (T506) is characterized in that common welding rod is applied in the soldering ironcasting, comprises spheroidal graphite cast-iron and grey casting.

2,, it is characterized in that the method for soldering ironcasting with the described common welding rod of claim 1:

(1) prepare before the weldering:

Select common welding rod-T506 hydrogen controlled electrode for use, core diameter 4mm, welding current intensity 160～170A, it is stand-by after 1-2 hour to be placed on 250～350 ℃ of drying box oven dry.

(2) selecting floating voltage for use is the above ac arc wedling machine of 70V, and (DC arc welder carries out reversal connection) places indoor and outdoor, and temperature does not have humidity on every side more than 10 ℃.

(3) give heat:

At first given heat with the T506 hydrogen controlled electrode to carrying out spot welding around the salvaging casting, it gives by the use of thermal means is that the touring segmentation dot welding method of even number gives heat: adopt the touring heating of even number symmetry to give hot method to spot welding place of round salvaging casting and give heat; Take the segment equalization heating to give heat to straight line or curve salvaging casting.

(4), welding:

Apply one deck white powdery industrial sodium carbonate to giving hot-cast part weld bond place, weld with the T506 welding rod then, adopt multilayer welding, multi-pass welding in the welding process, every layer is adopted the short welding bead that disperses weldering, discontinuous welding, want simultaneously layering, shunting to apply one deck sodium carbonate, postwelding is the hammering workpiece immediately.

(5), slow cooling, windproof, moistureproof.

Foundry goods after the welding carries out the nature cooling, and windproof, protection against the tide can be worked after 2 hours.