The Jones & Laughlin Steel Corp. No. 61 was a 23" gauge 0-4-0T steam locomotive built by the HK Porter Co. in Pittsburgh, PA in March 1944 under works number 7614 for use at the J&L South Side Works.
Interplant rail operations at the J&L South Side Works up until the late 1950's included standard and 23" gauge. The narrow gauge primarily served the No. 1 and No. 2 open hearth plants and the Polishing mill facilities. Due to the immense weight of ingot mold trains handled by the narrow gauge, locomotives of increasing size, weight and power were procured from HK Porter.
J&L 61 was one of seven such locomotives (numbered 57-63) built between 1937 and 1945 and are the heaviest (by axle loading) two foot gauge locomotives built for American railroads. With over 16,000 lbs. of tractive effort and a weight in working order of 93,000 lbs., the J&L Porters had the ability to move thousand ton and heavier ingot mold trains on a daily basis.
Of the seven of this type of locomotive originally built for Jones & Laughlin Steel for their 23" gauge railroad at the Pittsburgh Works, only four of them still exist. J&L 61 and 63 were both scrapped at some point before 1970. Their siblings J&L 58, 57, 60, and 62 still exist while J&L 59 has only been partially scrapped.