The company was established in 1871 as an engineering firm by two brothers, George and James Weir, founding
G. & J. Weir Ltd. The Weir brothers produced numerous groundbreaking inventions in pumping equipment, primarily for the Clyde shipyards and the steam ships built there. These pumps became extremely well known for their use as
boiler feedwater pumps, and for ship's auxiliary equipment such as
evaporators. During 1886, the company established a new machine shop in
Cathcart alongside a recently extended railway line. Under the leadership of
W D Weir, the company turned to producing munitions and war
materiel during the
First World War. In addition to shells, it manufactured aero-engines and whole aircraft, including the
Royal Aircraft Factory F.E.2 fighter and bomber. By the end of the conflict, in excess of 1,100 aircraft had been completed by the firm. During the
interwar period,
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 during its existence. In 1943, the firm provided the finances for the construction of the
W.9, an experimental helicopter, to
Air Ministry requirements. The company was
first listed on the London Stock Exchange in 1946. In December 1968, Weir Group issued an offer to purchase the rival British pump manufacturer
Worthington-Simpson, following an offer by
Studebaker-Worthington. During 1969, Studebaker-Worthington acquired Worthington-Simpson. After some negotiation, Weir's acquired 50% of Worthington Simpson. A new joint-venture company named Worthington Weir was set up to handle international sales of the two parent companies. The debt taken on by Weir to acquire their share of Worthington-Simpson was denominated in
Deutsche Marks, and as that currency strengthened against both the
Sterling and the
Dollar, it became increasingly expensive to service. While Worthington-Simpson was a profitable venture, it did not cover the cost of this debt. In response to the company's debt burden, Weir Group was compelled to sell off numerous assets and undertook financial reorganization in 1981. Following this reorganization,
Derald Ruttenberg and
Jacob Rothschild gained effective control of 40% of the company; Ruttenberg became a board member. Amid the reorganization, the
3rd Viscount Weir, who had been chairman since 1972, stepped down to vice chairman. However, Lord Weir regained the chairmanship in 1983 and served in this role until 1999. During 1989, the company acquired Hopkinsons, an
Huddersfield-based company manufacturing valves and controls.
21st century visiting a Weir facility in
Dubai in 2011|thumb During July 2005, Weir sold its
desalination and water treatment businesses, (Weir Westgarth, Weir Entropie and Weir Envig) to
Veolia Water Systems, part of the water division of
Veolia Environnement: Weir Westgarth had been a pioneer of the
multi-stage flash distillation process used predominantly to produce desalinated water from
seawater. During May 2007, the company sold its
Glasgow-based business
Weir Pumps to
Jim McColl's
Clyde Blowers plc, with the pump company subsequently being renamed to Clyde Pumps Ltd. In early 2006, it was reported that, amid allegations that the company had paid a multi-million pound
bribe to
Saddam Hussein's
Iraq, Weir Group acknowledged that it had parted company with several employees over the claims. In December 2010, Weir Group pleaded guilty to breaching
UN sanctions imposed on Iraq between 2000 and 2002. Judge Lord Carloway of The High Court in Edinburgh fined the company £3m along with a confiscation order of £13.9m. Following this judgement, the company continued to operate in Iraq. In 2010, Weir Group formed an agreement with the Japanese conglomerate
Mitsubishi Heavy Industries to cooperate on pump-related work on new
nuclear power stations. During August 2011, the company announced record profits of £178 million, having risen during the first six months of the year by 24%; orders were also up substantially. One year later, the firm was involved in a bidding war for the Australian mining company Ludowici, but was ultimately outbid by the Danish engineering firm FLSmidth. In 2014, Weir Group sought to discuss an envisioned merger between itself and the Finnish engineering firm
Metso Corporation; however, the board of the latter unanimously rejected the initiative. A £3.7 billion bid to takeover Metso was similarly unsuccessful. During February 2015, the company issued a
profit warning predicting significant losses after the US
shale market went through a contraction. In response, Weir Group opted to reduce its workforce by approximately 650. Due to the persistence of the oil market's downturn, further jobs cuts followed in late 2019. In February 2019, the company sold their flow control division to
First Reserve. That same year, Weir Group was awarded its largest ever order, valued at £100m, to supply mining equipment for a large iron ore scheme in Western Australia. During the late 2010s, Weir Group decided that, following losses in its US-centric oil and gas activities, it would reorient towards the mining industry, for which it was developing new technologies to reduce environmental impact. During October 2020, the company sold their oil and gas division to the American equipment manufacturer
Caterpillar Inc. in exchange for $405 million. In April 2022, the company announced that it was withdrawing from its business activities within Russia following the
Russian Invasion of Ukraine. That same year, Weir Group formed an alliance with Swiss Tower Mills Minerals AG to market the latter's vertical stirred grinding mills. == Acquisitions ==