Cores manufactured by OMEM, regardless of the material they are made of, can be supplied with additional processes, in order to make them more suitable for customers’ applications. Some processes are compulsory, such as impregnating the cores to be cut. Sometimes additional processes are recommended, such as hardening, to make the cores stronger and to prevent any handling related stresses. This is why OMEM normally hardens cores to be supplied to foreign markets.
Thin cores or smaller sized cores which make them more prone to warping, are also hardened. OMEM believes to have a wide knowledge of potential critical issues that could be faced by magnetic cores during their use and, regardless of the process used by the customer, is able to recommend additional processes to be carried out, by providing exhaustive technical details, gained from analyzing an endless number of case histories and therefore confirmed by practical experience.

  • Hardening: strongly recommend for thinly wound cores and low strip height. Always recommended for Nanocrystalline cores.
  • Vacuum impregnation: must always be carried out for cores to be cut or for audio applications.
  • Epoxy resin coating: the fully automated plant used by OMEM allows cores of any material to be quickly and affordably epoxy coated. The resin is deposited onto the suitably heated cores and is hardened with heat. According to the core weight, this process allows a 0.05 to 1mm thick coating to be achieved. The epoxy resin coating process allows a satisfactory mechanical resistance to be achieved; this process also allows cores to be insulated; however, OMEM cannot guarantee with total confidence that this coating is suitable for all types of applications, as other external factors, unknown to OMEM do play a part.
  • Core wrapping with polyester strips. Upon request, O.M.E.M. can wrap bare, hardened or epoxy resin coated cores (nanocrystalline) with a polyester strip with variable thicknesses and stacking methods.
  • Caps for Silicon-Iron and Nickel-Iron cores. For Silicon-Iron and Nickel-Iron cores, partially covering caps are available, provided to protect and smooth out the core edges and to prevent damages to the copper wires during the coiling process. New additional sizes to those already supplied as standard can be added for large volumes. The caps offered are made of different materials, most frequently polyamide 6.6 or polycarbonate. They may be reinforced with fibreglass to increase their resistance to heat.
  • Caps for nanocrystalline cores. For nanocrystalline cores, very sturdy and fully protective caps are required. Thicker and sturdier caps are available compared to the caps provided for SiFe and NiFe cores, but only for a very small range of formats. If the required product volume is large, custom made caps may be produced in special plastic material or aluminium.
  • Boxes for nanocrystalline cores. For small volumes of cores, special caps or boxes made of different materials can be supplied: with welded iron base and FR4, bakelite or similar type insulating material cover, entirely made of precompressed pressboard or by assembling aluminium rings placed inside and outside the cores and pre-compressed pressboard base and cover.