About Jasflo

The Jasflo process

The Jasflo process enables a component comprised of a relatively soft material to be inserted through a sheet of a harder material without the necessity for providing a drilled or punched hole.

The technique is used for the insertion of components such as ptfe feed-through terminals, stand-off terminals, nylon grommets, bushes and bearings, and windows made from Perspex, the technique offering a highly economic means of manufacturing printed circuit boards and electronic assemblies. The plastic inserts are rapidly assembled into the base sheet material in a press operation, using single or multi-insertion tools.

The tool consists essentially of a top tool (punch), a bottom tool (die) and a shroud, the function of the latter being to constrain the plastic insert when it is subjected to pressure in the assembly procedure.

In a typical assembly operation, the following takes place: The plastic component to be inserted is placed in the shroud which is then clipped into the top tool. The base sheet (usually metal) is placed over the die. Operation of the press causes the punch to come down into the shroud, thus applying pressure to the top of the component which is constrained radially by the shroud. The bottom surface of the shroud has a sealing -ring, and is maintained in sealing contact with the metal sheet by the pressure exerted by a spring in the top tool. As the press-stroke continues, the punch continues to come down in the shroud, thus causing a build-up of pressure between the plastic component and the metal sheet. The pressure increases until the shear resistance of  the sheet is overcome and the component punches its own hole through the sheet, and the blanked-out piece of sheet is cleared through the die. This relieves the pressure, and the lower portion of the component forces its way through the hole sheared out of the sheet. Because it has a degree of elasticity, the inserted component expands to key itself to the aperture in the sheet.  

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