Background From the cast house floor to iron runners and ladles, Fibretech’s unique range of stainless steel fibres for the Iron making industry offer:
· Improved refractory performance
· Lower installation costs
· Better operating efficiency
· Lower refractory costs and increased operating plant availability
Blast Furnace RefractoriesBlast furnace refractories are repeatedly bombarded with hot air (thermal shock) and charging of iron ore, coke etc (mechanical shock). Fibre reinforced refractory will resist these forces which otherwise crack and spall castable, shortening its working life and increasing maintenance costs.
In addition ladle charging, lance injection and pouring operations cause refractory to crack and spall. In these applications fibres can considerably extend service life by strengthening the refractory.
Figure 1. Refractory areas in an iron blast furnace which can benefit from stainless steel reinforcement.
Feed AreaDowncomers and OfftakesHot, high velocity waste gases and particles impact and erode the refractory lining, reducing thermal efficiency and increasing maintenance costs. Since fibre addition improves refractory toughness by more than 100%, maintenance costs here can be halved. ME 446 has excellent chemical resistance to the gas mix present in this part of the blast furnace.
Recommendation: ME 446
Bell Charging SystemCharging can weaken the refractory and distort the vessel's steelwork. A cracked lining compromises insulation efficiency and reduces the gas tight seal necessary to prevent unwanted gas escape. By prolonging the integrity of the lining, fibres reduce these costs.
Recommendation: ME 430
Wear Plate Area Refractory linings in this application are subject to considerable mechanical wear from repeated charging. Fibres prevent the lining cracking and spalling, improving thermal insulation and stopping damage to the vessel's upper structure.
Recommendation: ME 430
Torpedo LadleThroatLadle charging, lance injection and pouring operations cause the throat refractory to crack and spall. Fibres help retain the lining intact, considerably extending its service life and the period between interim repairs.
Recommendation: ME 446
Throat ApronRepeated iron splashing can crack the refractory apron, causing loss of protection for the steel casing and ultimately lead to expensive steelwork repair. A fibre reinforced lining will typically have double the service life of a non-fibre castable in this application.
Recommendation: ME 430
Throat CoverRadiant heat iron splashing and mechanical shock quickly crack and spall the refractory reducing the cover's insulating efficiency and working life. ME fibres minimise the effects of thermal and mechanical shock so maintenance and energy costs remain low.
Recommendation: ME 446
NB: Fibretech ME fibres can also be used to extend the life of the ladle's impact pad.
Injection LancesLances endure repeated thermal cycling, often directly from ambient to 1500°C-1600°C, Thermal shock is extreme in this most severe of tests. Cracked and spalled refractory quickly reduces the lance's working life. As a result steel fibre reinforcement is now standard in all modern lance refractory.
Recommendation: ME 446
Blast FurnaceTuyeres and GoosenecksThese linings are repeatedly bombarded with blasts of hot air (thermal shock) and at times added coal (mechanical shock). Fibre-reinforced refractory will resist these forces which otherwise crack and spall castable, shortening its working life and increasing maintenance costs.
Recommendation: ME 446
Working Floor AreaHot metal splash and mechanical wear from heavy plant can crack casthouse floor concrete, making movement difficult and sometimes dangerous. Fibres are ideal here with economies often of 200-300%.
Recommendation: ME 430
Upper StackIn the Upper Stack mechanical abrasion is caused by the impact of the charge and subsequent settling in layers. While some cracking is unavoidable ME fibres contain and minimise damage. Lining improvements have resulted in significant reductions in interim gunning repairs and maintenance costs.
Recommendation: ME 430
Blast Furnace RunnerBlast Furnace Runner Security LiningDifferential thermal movement of the runner's steel casing and refractory lining can result in damage to both components. Subsequent maintenance and energy costs can prove expensive. Fibres can eliminate these costs by strengthening the refractory, preventing spalling and improving thermal insulation.
Recommendation: ME 446
Blast Furnace Runner CoverThermal expansion of the steel shell, hot metal splashes and lifting can crack a plain refractory lining, resulting in spalling and a reduction in thermal insulation efficiency. Fibres control cracking, retain the refractory in place and maximise shell protection. Thermal efficiency is maintained and costs are minimised.
Recommendation: ME 446
Main Runner Syphon BoxHot metal erosion of the box dueling causes spalled refractory and the loss of flow control and slag separation. Fibres will reduce spalling, normally doubling refractory performance.
Recommendation: ME 446
Weirs and DamsThese precast shapes suffer repeated thermal shock in their short lives. Movement results in cracking and a reduction in strength. Both refractory performance and iron quality are reduced. At 3-4% by weight, fibres can improve performance by 100% or more.