RUNNER OF DUST-CONTAINING EXHAUST GAS BLOWER AND REPAIR METHOD THEREOF

To provide a runner having a longer life as compared to the conventional technique and to provide a repair method of the runner capable of shortening a repair period as compared to the conventional technique.SOLUTION: A runner of dust-containing exhaust gas blower is formed of two layers of a primary and a secondary build-up welding having respective thickness of 1.5 mm or more and 3.0 mm or less on at least a part of the surface. The average value Hvm of micro Vickers hardness of base material to be subjected to primary build-up welding is 100 to 400, the average value Hvu of micro Vickers hardness of secondary build-up welding is 1000 to 1400, the average value Hvl of micro Vickers hardness of primary build-up welding is 450 to 950 and chromium content of primary build-up welding is set to be 10 to 30 mass%, and hardness gradient α in the thickness direction between the secondary build-up welding and the base material and hardness gradient β in the thickness direction between the secondary build-up welding and the primary build-up welding are respectively 18 or more and 320 or less.SELECTED DRAWING: Figure 1 【課題】従来に比べて寿命の長いランナーを提供する。また、従来に比べて補修期間を短縮することが可能なランナーの補修方法を提供する。【解決手段】表面の少なくとも一部に、それぞれ１．５ｍｍ以上３．０ｍｍ以下の厚さの下盛り及び上盛りの２層の溶接肉盛を施した、含塵排ガスブロワーのランナーであって、下盛りを施す母材のマイクロビッカース硬さの平均値Ｈｖｍが１００〜４００、上盛りのマイクロビッカース硬さの平均値Ｈｖｕが１０００〜１４００、下盛りのマイクロビッカース硬さの平均値Ｈｖｌが４５０〜９５０、且つ下盛りのクロム含有量が１０〜３０質量％とされ、上盛りと母材間の厚さ方向の硬度勾配αと上盛りと下盛り間の厚さ方向の硬度勾配βがそれぞれ１８以上３２０以下である。【選択図】図１