CN101407002A

CN101407002A - Back slag self-protecting flux-cored wire for T92/P92 steel tungsten electrode argon arc backing weld

Info

Publication number: CN101407002A
Application number: CNA2008102276932A
Authority: CN
Inventors: 陈玉成; 徐德录; 韩钰; 丛相州; 李现兵; 马光; 聂京凯; 王立全
Original assignee: China Electric Power Research Institute Co Ltd CEPRI
Current assignee: China Electric Power Research Institute Co Ltd CEPRI
Priority date: 2008-11-28
Filing date: 2008-11-28
Publication date: 2009-04-15
Anticipated expiration: 2028-11-28
Also published as: CN101407002B

Abstract

The invention provides a back surface slag melting self protection flux-cored wire for T92/P92 steel tungsten electrode argon arc backing weld and belongs to the material processing engineering welding filed. The aim of the invention is to provide a welding wire for argon arc backing weld which has simple welding process and high efficiency. The welding wire adopts a steel belt bag to cover alloy powder. A fill rate is between 35 and 39 percent, and the powder of the flux-cored wire consists of the following components in weight percentage: 2 to 4 percent of fluorite, 22 to 28 percent of rutile, 5 to 8 percent of quartz, 2 to 4 percent of feldspar, 3 to 7 percent of cryolite, 1 to 2 percent of sodium carbonate, 3 to 7 percent of metallic manganese, 2 to 4 percent of ferrosilicon, 2 to 4 percent of nickel powder, 24 to 28 percent of chromium powder, 0.8 to 1.5 percent of molybdenum powder, 3.5 to 5 percent of ferrotungsten, 1.5 to 3.5 percent of ferrovanadium, 0.4 to 0.8 percent of ferroniobium, 0.2 to 0.4 percent of ferroboron, 0.8 to 1.2 percent of nitrogenized manganese and the balance of iron powder. The welding wire has the advantages of the welding seam back surface slag melting self protection, simple construction process and the like.

Description

T92/P92 steel tungsten electrode argon arc backing weld back slag self-protecting flux-cored wire

Technical field

The invention belongs to the welding field in the Materials Processing Engineering, be specifically related to be applicable to that Utility Boiler Superheater, reheater are with small diameter tube T92 and the main steam line bottom welding bead backing welding back slag self-protecting flux-cored wire with thick-walled pipe P92 steel.

Background technology

Along with the fast development of power industry, the TP2/P92 steel of being developed by Japan has obtained extensive use in the construction of overcritical and ultra supercritical fired power generating unit.At present, the bottom argon arc backing weld of T92/P92 steel adopts back side argon-filled protection measure more, and technology is numerous and diverse, and efficient is lower, and yet there are no report for the flux-cored wire of realizing the back slag self-shield.

Summary of the invention

The objective of the invention is to solve the problems of the prior art, and a kind of T92/P92 steel tungsten electrode argon arc backing weld back slag self-protecting flux-cored wire is provided.

T92/P92 steel tungsten electrode argon arc backing weld provided by the present invention adopts steel band clad alloy medicinal powder with back slag self-protecting flux-cored wire; filling rate is 35～39%; the component at medicinal powder end and content thereof are (representing with mass percent): fluorite: 2～4%; rutile: 22～28%; quartzy: 5～8%; feldspar: 2～4%; ice crystal: 3～7%; sodium carbonate: 1～2%; manganese metal: 3～7%; ferrosilicon: 2～4%; nickel powder: 2～4%; chromium powder: 24～28%; molybdenum powder: 0.8～1.5%; ferrotungsten: 3.5～5%; vanadium iron: 1.5～3.5%; ferro-niobium: 0.4～0.8%; ferro-boron: 0.2～0.4%; nitrogenized manganese: 0.8～1.2%, surplus is an iron powder.

The effect of each component is as follows in the alloy medicinal powder:

Rutile: the composition of main slag making, can improve the spreadability and the removability of slag of slag;

Fluorite: increase slag fluidity, reduce viscosity coefficient of dross;

Feldspar: mainly be slag former, increase slag fluidity, reduce viscosity coefficient of dross, the protection weld seam;

Quartzy: main effect is slag making, reduces slag basicity simultaneously, regulates coating viscosity;

Ice crystal: slag former, and reduce slag concentration, help reducing hydrogen concentration;

Sodium carbonate: gas making and stabilising arc effect;

Crome metal: transition chromium in weld seam obtains necessary evanohm;

Manganese metal: deoxidation, transition manganese in weld seam obtains necessary manganese alloy; Reduce austenite to ferritic transition temperature, suppress sulfide and assemble, improve the intensity and the toughness of weld metal at crystal boundary;

Nitrogenized manganese: transition nitrogen and manganese in weld seam, but N crystal grain thinning;

Nickel powder: transition nickel in weld seam makes weld metal obtain necessary nickel alloy; Help improving the impact flexibility of weld metal;

Molybdenum powder: transition molybdenum in weld seam makes weld metal obtain necessary molybdenum alloy;

Ferrosilicon: deoxidation, transition silicon in weld seam plays the effect of butt welded seam metal strengthening simultaneously;

Ferro-niobium: transition niobium in weld metal makes weld metal obtain necessary niobium alloy;

Vanadium iron: transition vanadium in weld metal makes weld metal obtain necessary vanadium alloy;

Ferro-boron: transition boron in weld metal makes weld metal obtain necessary boron alloy;

Ferrotungsten: transition tungsten in weld metal makes weld metal obtain necessary tungsten alloy

Iron powder: improve conductance, increase deposition efficiency.

The present invention has following beneficial effect: by the self-shield of back of weld slag, exempted back side argon-filled protection measure, simplified construction technology, improved production efficiency.

The invention will be further described below in conjunction with the specific embodiment.

The specific embodiment

Selecting width among the following embodiment for use is 12～14mm, and thickness is the high-quality mild-carbon steel strip clad alloy medicinal powder of 0.3～0.5mm, and steel band is eliminated rust after the oil removing, is rolled into U type section slot; Then filling granularity in U type groove is the dry alloy medicinal powder of handling of 100～200 purposes, and filling rate is 35～39%; After being rolled in medicinal powder package in the U type groove, closing up is 0 type, again through drawing tube reducing to 2.0～2.5mm.

Embodiment 1

Selecting width for use is 13mm, thickness is the high-quality mild steel steel band clad alloy medicinal powder of 0.3mm, the composition of medicinal powder and content thereof are (representing with mass fraction): fluorite: rutile 3%: quartz 28%: feldspar 5%: ice crystal 3%: sodium carbonate 3%: manganese metal 1%: ferrosilicon 7%: nickel powder 4%: chromium powder 2%: molybdenum powder 26%: ferrotungsten 1.5%: vanadium iron 3.5%: ferro-niobium 1.5%: ferro-boron 0.4%: nitrogenized manganese 0.2%: 0.8%, and surplus is an iron powder; Filling rate is: 37～39%.

Embodiment 2

Selecting width for use is 13mm, thickness is the high-quality mild steel steel band clad alloy medicinal powder of 0.3mm, the composition of medicinal powder and content thereof are (representing with mass fraction): fluorite: rutile 4%: quartz 24%: feldspar 8%: ice crystal 2%: sodium carbonate 7%: manganese metal 2%: ferrosilicon 5%: nickel powder 3%: chromium powder 3%: molybdenum powder 24%: ferrotungsten 1.2%: vanadium iron 4%: ferro-niobium 2.5%: ferro-boron 0.6%: nitrogenized manganese 0.3%: 1.0%, and surplus is an iron powder; Filling rate is: 36～38%.

Embodiment 3

Selecting width for use is 13mm, thickness is the high-quality mild steel steel band clad alloy medicinal powder of 0.3mm, the composition of medicinal powder and content thereof are (representing with mass fraction): fluorite: rutile 2%: quartz 22%: feldspar 6%: ice crystal 4%: sodium carbonate 5%: manganese metal 1.5%: ferrosilicon 3%: nickel powder 2%: chromium powder 4%: molybdenum powder 28%: ferrotungsten 0.8%: vanadium iron 5%: ferro-niobium 3.5%: ferro-boron 0.8%: nitrogenized manganese 0.4%: 1.2%, and surplus is an iron powder; Filling rate is: 35～37%.

After embodiment 1,2 and 3 prepared welding wires are made sample by following welding conditions,, measure composition (as shown in table 1), ambient temperature mechanical properties (as shown in table 2) and the high temperature, short time mechanical property (as shown in table 3) of its deposited metal by the relevant criterion requirement.

Welding variables is as follows:

Welding method: dc reverse connection method; Welding current: 110～130A; Weldingvoltage: 11～14V; Speed of welding: 50～100mm/min; Interlayer temperature: 150～200 ℃; Layer thickness≤2.5mm; The post weld heat treatment temperature: 760～770 ℃, temperature retention time: 2～4h.

The chemical composition wt% of table 1 deposited metal

Table 2 example deposited metal ambient temperature mechanical properties

Table 3 example deposited metal high temperature (600 ℃) is mechanical property in short-term

Can find out from the above table result: the prepared T92/P92 steel tungsten electrode argon arc backing weld of the present invention uses the back slag self-protecting flux-cored wire processing performance good, and composition and mechanical property reach the requirement of relevant criterion, can satisfy T92/P92 steel welding needs.

Claims

1; a kind of T92/P92 steel tungsten electrode argon arc backing weld back slag self-protecting flux-cored wire; it is characterized in that; described welding wire adopts steel band clad alloy medicinal powder; filling rate is 35～39%; the component of medicinal powder and content thereof are; represent with mass percent: fluorite: 2～4%; rutile: 22～28%; quartzy: 5～8%; feldspar: 2～4%; ice crystal: 3～7%; sodium carbonate: 1～2%; manganese metal: 3～7%; ferrosilicon: 2～4%; nickel powder: 2～4%; chromium powder: 24～28%; molybdenum powder: 0.8～1.5%; ferrotungsten: 3.5～5%; vanadium iron: 1.5～3.5%; ferro-niobium: 0.4～0.8%; ferro-boron: 0.2～0.4%; nitrogenized manganese: 0.8～1.2%, surplus is an iron powder.