About us

DIA Pumpen GmbH attaches great importance to fully understanding the needs and expectations of its customers. This enables optimum customer advice, product development and realization as well as continuous customer support. The company’s goal goes beyond mere customer satisfaction; it strives to exceed customer expectations in the long term.

On June 1, 1896, the company Hammelrath & Schwenzer oHG was founded by the businessman Theodor Hammelrath and the engineer Gustav Schwenzer. The focus was on the manufacture and sale of pumps for various applications, from construction and agriculture to industry. Production started in Düsseldorf-Bilk, initially with manually operated diaphragm pumps, which were later developed into power-driven pumps with electric and combustion engines.

The company expanded its range to include accessories such as hoses and fittings in order to offer customers ready-to-use solutions. Continuous design improvements have optimized the performance and handling of the products. This led to the granting of domestic and foreign patents and utility model protection. During this time, the focus was also on the development and sale of vacuum systems for groundwater lowering, storage and wastewater pumping.

The introduction of IT in all areas of the company ensured that the company met the requirements of modern corporate management. The management changed several times over the years, with people such as Dipl.-Ing. Gustav Schwenzer jun., Max von Diemer, Johann Braun and Heinz Classen taking over the reins. The company structure changed from an oHG to a KG, and later to DIA Pumpenfabrik Hammelrath & Schwenzer GmbH & Co KG.

In 1998, the shareholders decided to liquidate the company. Sales activities 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 to ensure consistent product quality and service continuity.

Today, DIA Pumpen GmbH operates successfully in Langenfeld/Rhineland. Despite previous challenges, the company has repositioned itself and relies on many years of expertise, technical innovations and meeting customer needs. The company is continuing the contractual obligations of the former DIA Pumpenfabrik, Hammelrath & Schwenzer GmbH & Co. KG in full. This maintains the quality and reliability of the products and services.