About DIA Pumps

DIA Pumpen GmbH places great importance on fully understanding the needs and expectations of its customers. This enables optimal customer consultation, product development and implementation, as well as continuous customer support. The company’s goal goes beyond mere customer satisfaction; it strives to consistently exceed customer expectations.

On June 1, 1896, the firm Hammelrath & Schwenzer oHG was founded through a partnership between businessman Theodor Hammelrath and engineer Gustav Schwenzer. The company focused on the manufacture and distribution of pumps for various applications, ranging from construction and agriculture to industry. Production began in Düsseldorf-Bilk, initially with hand-operated diaphragm pumps, which were later developed into power-driven pumps equipped with electric and internal combustion engines.

The company expanded its product range by adding accessories such as hoses and fittings in order to offer customers ready-to-use solutions. Through continuous design improvements, the performance and handling of the products were optimized. This led to the granting of domestic and foreign patents and utility model protection. During this period, the focus was also on the development and distribution of vacuum systems for groundwater lowering, maintenance, and wastewater extraction.

The introduction of computer systems across all areas of the company ensured that it met the requirements of modern business management. The company’s leadership changed several times over the years, with individuals such as Dipl.-Ing. Gustav Schwenzer Jr., Max von Diemer, Johann Braun, and Heinz Classen taking the helm. The company’s legal structure evolved from a general partnership (oHG) to a limited partnership (KG), and later to DIA Pumpenfabrik Hammelrath & Schwenzer GmbH & Co. KG.

In 1998, the shareholders decided to liquidate the company. Sales operations were discontinued on January 31, 1999. However, DIA Pumpen GmbH was founded on February 1, 1999. The shareholders consisted of former employees of the former DIA Pumpenfabrik. They took over the know-how, technical equipment, and data processing systems to ensure consistent product quality and continuity of service.

Today, DIA Pumpen GmbH operates successfully in Langenfeld, Rhineland. Despite earlier challenges, the company has repositioned itself and relies on its long-standing expertise, technical innovations, and a commitment to meeting customer needs. The company continues to fully honor the contractual obligations of the former DIA Pumpenfabrik, Hammelrath & Schwenzer GmbH & Co. KG. This ensures that the quality and reliability of its products and services are maintained.