Mechanical metal-to-metal sealing plugs reduce operational cost and waste associated with threaded plugs, ball bearings and retaining adhesives. A zero-defect solution with substantial aftermarket ​​​​quality gains for whole life value.

Reducing operational complexity, boosting efficiency and reducing waste, are just some of the common strategic goals associated with contemporary manufacturing processes. Though the Koenig Expander sealing plug has been represented by Boneham & Turner Ltd since the 1970’s, its relevance in advanced manufacturing applications has never been more significant. Manufacturers in the automotive and aerospace markets are continuously considering methods and products for minimising contact with workpieces and reducing cycle times, as well as, minimising waste and the use of secondary adhesives. This is vital in-order to preserve competitive advantage, focus on innovation and deliver a more sustainable and environmentally conscious solution.

Initially intended for the hydraulics industry, the Koenig Expander’s core principle is synonymous with its name, using an expanding method; the Koenig Expander is categorised by two variants. The MB series of plug utilises a punch to press a ball bearing into an outer sleeve, anchoring the plug into the hole. The SK, LK and HK variants all use a pull philosophy. Using a setting tool, the mandrel is retracted and disengaged, expanding the main body of the plug into the sleeve, again securing the plug into the machined hole. This process provides a high-pressure seal for air and liquid.

Globally the Koenig Expander is used in automotive applications such as sealing drilled holes left in transmission housings after machining oil ways. Automotive manufacturers are benefiting from the one-piece solution provided by the Expander. For example, replacing non-standard threaded plugs and industrial adhesives which, as with ball bearings, are deemed as an inexpensive alternative for sealing holes. These methods are in fact more costly, both from an operational perspective and long-term quality performance. The Expander requires no special machining or second operation on the transmission unit, with no threading of the hole required. The mechanical expanding principle means no adhesive is required, removing another operation and the need for cleaning material inventory. Using adhesives on threaded plugs or ball bearings also creates problems with contamination in the transmission and solvent waste during assembly, unlike the expander. The Koenig plug also prevents human error associated with multi operation assemblies, offering a zero-defect proposition that is 100% inspected throughout its production, utilising optical, mechanical, human and Eddy-current inspection techniques. Emphasis is placed on quality with the Expander, from the mechanical design to the installation.

Boneham & Turner representatives operate closely with production engineers to provide, not only the best plug for the application, but the installation tools and processes to reduce operation and assembly times, whilst providing an inventory and logistics solution.