Closing and Sealing Systems

In various areas and applications of the industry, from gearboxes and pumps to engine blocks, coolant and lubricant circuits or process-related bore holes are required to ensure the function of the component. These circuits have to be closed or sealed.

Usually, screw plugs (with or without under-head seal) or expander solutions are used for sealing holes. In contrast to screw plugs, expanders cannot be removed without being destroyed. In addition, these sealing elements close off the hole, but require complex preparation of the bore hole. For example, drilling, countersinking, thread cutting, milling of the head contact surface and cleaning the thread when using screw plugs is very costly and time-consuming.


  • Sealing of boreholes to prevent liquids and gases from entering from the inside
  • Closing of the bore hole against dirt from the outside
  • Pressure-resistant closing and sealing of boreholes and thus universally applicable

b&m Brands

b&m-KL PLUG®

Closing and sealing system for holes with or without pressure load

b&m Innovation