Abstract
With 60 per cent of the steam-boiler horsepower of the United States in locomotives, which operate under widely diverse conditions and with waters of many compositions, this field offers extensive opportunity for the study of embrittlement cracking. The authors present a record of the experience of The Chesapeake & Ohio Railway with intercrystalline cracking as representative of the more recent work being done by the railroads to combat this form of metal deterioration. The paper deals with the investigation of various inhibitors, covering a period from 1933 to the present time, based on extensive testing with the embrittlement detector applied to locomotives in service. It was found that sodium sulphate does not prevent or even delay embrittlement cracking; that waste sulphite liquor will prevent cracking of detector specimens on many boiler waters, failing in but few cases; and that sodium nitrate has essentially eliminated cracking of detector specimens on the entire system of The Chesapeake & Ohio Railway.
