Insert Technology For Plastics, Composites And Metal Alloys

Product Description

The Tappex HiMould range of inserts has been designed as a technical advancement on the Yardley style of insert, specifically for moulding-in during the cycle of the moulding machine. This is the traditional method of placing metal inserts in plastic mouldings, although normally the insert is laboriously screwed onto threaded pins located inside the mould tool. With the HiMould range, this costly and inefficient process becomes unnecessary, as the insert can be rapidly located on to Plain Pins giving higher productivity and reducing tool down time. Despite the use of plain pins the unique design of the HiMould insert still gives guaranteed Flash Free threads. Tappex HiMould inserts have become widely used in all types of thermoplastic and thermoset plastic mouldings.

There are three types of HiMould inserts, which should provide a complete range of standardised female inserts to cater for different design criteria.

Design Features

Easier moulding ejection because the HiMould insert is located on a plain pin; there are no secondary operations required before removal of the moulding from the mould tool. This allows the use of sleeve ejectors or a centralised ejection screw; in turn this significantly simplifies tool design and produces easier moulding injection during production, thereby increasing productivity.

Recessed - The HiMould insert can be used in preference to post-mould installed inserts where the application of the insert is in a deep recess. In this type of situation, it is easier to locate inserts in the mould tool, where the recess in the moulding is reflected in a protruding portion in the tool, than to attempt to post-mould install in a difficult situation.

Standardised design - The HiMould range of inserts has been designed as a standard item, which caters for all types of applications in the smallest possible insert diameter. This allows the designer to standardise and avoid the necessity of designing a special insert for each new application. In turn, this eliminates high costs for manufacturing specials and enables large stocks of standard components to be held, giving immediate delivery of small or large quantities.

Thin Wall applications - It is possible to mould-in HiMould inserts very close to the edge of mouldings, or in situations where there are thin walls or bosses. This would be impractical for post-mould installed inserts. Maximum performance is created by the external diamond knurl form which includes two undercuts to knurl depth. After moulding-in, a large number of shear points are created over the whole length of the insert. This gives better axial and radial performances than other mould-in inserts in relation to its diameter.

Rapid insert location is achieved by location in the mould tool on plain pins, giving an interference fit with the internal bore of the insert in a single quick operation. HiMould inserts can also be easily installed into the top half of the mould tool without the risk of the insert coming loose before or during the mould cycle

All material types can be used with HiMould inserts, whenever components are being moulded or cast.

The range ultimately covers M3 to M12 internal thread sizes, M2 and M2.5 are available as Yardley style inserts without the two undercuts. The three types of HiMould insert are shown below:

Type A Easy location in mould tool. A standardised insert and pin design cutting down design time. The open face is accurately machined at right angles to the axis of the insert. The square face fits flush with the mould tool and eliminates flash.	HiMould A type
Type B Easy location in mould tool. A standardised insert and pin design cutting down design time. It is possible to hold the length of the B type insert to +0.05mm/-0.05mm, to enable the tool to shut solid on the insert giving flash free threads.	HiMould B type
Type C Easy location in mould tool. Guaranteed grip on the mould tool pin especially in the top half of the mould tool, where inserts can easily become dislodged either before or during the moulding process. Guaranteed flash free threads. A longer length insert to cope with variation in bolt length and clamping thickness. A standardised insert and pin design cutting down design time. Excellent performance in foam materials where flashing is a greater problem due to the searching nature of the plastic. In any high pressure environment the 'C' type HiMould insert gives flash free threads, especially with low viscosity melts	HiMould C type