The Weir Group plc (LSE: WEIR) is an engineering company headquartered in Glasgow, Scotland.
It is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index.
The Company was established in 1871 as a pump manufacturing business G & J Weir.
Under W G Weir, the company turned to producing munitions and war materiel in the First World War. As well as shells, they manufactured aircraft including the Royal Aircraft Factory F.E.2 fighter and bomber.
James George Weir (aviator, son of James Galloway Weir) a director of the company formed the Cierva Autogiro Company. G & J Weir would be a financial supporter of the company for several years. In 1943, they provided the finances for the construction of the W.9, an experimental helicopter, to Air Ministry requirements.
It was first listed on the London Stock Exchange in 1947. Double-acting Weir steam pumps were virtually standard fitment on British-built steamships, being used for pumping water, fuel, air and much else well into the 1950s, as well as being used on other ships worldwide.