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Hanomag Lohnhärterei has emerged from what was formerly the Industrial Hardening Plant of Hannoversche Maschinenbau AG (Hanomag for short) and thus boasts a long tradition in heat treatment.

Since 1986, we have been an owner-managed family business, steadily and sustainably growing from 18 initial employees to over 650 current permanent employees.


The company history of Hanomag Lohnhärterei:


Legal form: Seehafer Holding GmbH & Co KG, the sites are GmbHs


Founding: 1986 at the headquarters in Hanover

Shareholders: Konrad Seehafer and Karsten Seehafer

External shareholders: 100% family owned

Heat treatment: Steel, aluminium and other metallic recyclables

Mechanical processing: Prototyping, pre-series and series

Employees: 650 (2018)

Trainees: 26 (2018)


Values ​​that are important to us:


As a management team, we focus on profitable growth and sustainable value increase. An effective management system and the consistent realisation of synergies across all business units and branches form the basis for our success.



Our strategic goals are based on the three-pillar model of sustainability, which means that we care equally about ecological, economic and social sustainability.



We fulfil our services constantly and with consistent quality. We regularly take quality checks and constantly optimise our processes.



We involve our business partners in the planning of future transactions and provide timely information about changes in the company.



We openly tell our customers and business partners that we are primarily interested in long-term business relationships in which both sides benefit from the relationship. We strive for equal business relationships - we are looking for partners on the same footing.



Our willingness to adapt to market and customer changes and to react quickly and without unnecessary bureaucracy to quantity and schedule changes is great proof of our extraordinary flexibility. We take on new challenges every day.


Open communication

Sound decisions require all available and relevant information as a basis. The honest exchange between business partners is a matter of course for us. Open communication helps both partners, creates quick solutions to problems and strengthens mutual trust.