Firms supplying rotary kiln systems to the cement industry are discussed because their contribution to the development of kilns profoundly influenced the history of the industry. The list is not comprehensive: I have restricted discussion to those manufacturers who supplied significant numbers of systems to firms in Britain and Ireland.
Equipment suppliers specialising in the cement industry were few in the early years, since early static kilns were "home-made", and grinding equipment was identical to that used in other processing industries. The particular needs of the industry for fine grinding of hard materials led firms to develop grinding equipment from the 1880s onwards, with European firms leading the way.
The development of the rotary kiln made further progress difficult or impossible for cement firms to attempt in-house, and led to the rapid formation of numerous firms offering more-or-less complete cement plants - a deal particularly attractive to the many new entrants to the industry around the start of the 20th century.
After the establishment of a well-tried design for rotary kilns in the USA, European engineering firms started designing kilns along the same lines, and the earliest successful European rotary kilns were developed more-or-less concurrently by FLS in Denmark and Polysius in Germany. Various other firms scattered around Europe entered the business, but there was an overwhelming concentration in Germany. Of the many firms making cement kilns before WWI, a fair number are still operational: Fellner & Ziegler (Frankfurt), Krupp (Essen), Loesche, MIAG (Braunschweig), Claudius Peters, Christian Pfeiffer (Kaiserslautern), G Polysius (Dessau). By the time the first British-made rotary kiln was installed in 1906, four Danish and sixty-two German kilns had been installed, and by 1912 a further twelve Danish and twenty German kilns had been installed, but only ten British: seven from Ernest Newell and three from Edgar Allen. By 1912, alarm at the prospects of war was prompting questions about this situation: frequent articles appear in The Engineer criticising the cement industry and making jingoistic and largely unfounded claims about the quality of British equipment. Despite this, only two British manufacturers actually supplied kilns before WWI. After the war, largely in order to re-deploy manpower and equipment previously engaged in armaments work, Vickers set up to make kilns, and rapidly became the largest British supplier, with a pseudo-international order book. First Newell, then Allen progressively withdrew from making kilns, leaving Vickers as the sole British supplier, and Vickers promptly shut down its entire cement equipment division in 1970. At this point, cement kiln manufacture ceased in the UK, although Newell's successors continue to make pyroprocessing equipment for less demanding applications. FLS and Polysius have since then consolidated their position as the largest suppliers world-wide, and nearly all the kilns installed in Britain in the last 35 years have been supplied by them.