LFT Mould

The LFT Mould is designed for high-volume injection moulding applications. Designed with accuracy and consistency in mind, it offers excellent shot precision and consistency. Its first-in-first-out melt transfer principle enables the correct shot dosing. Furthermore, the plunger injection unit requires low injection pressure, which is especially beneficial for LFT processing.

Side-action core
A Side-action mould is one of the most commonly used moulds. It enables a mold's external undercut to be formed without the need for an unscrewing device. This type of mould can also be used for internal undercuts. To achieve the internal undercut, a separate unwinding device is needed.

Side-action moulds are similar to injection-type moulds except that they have a means of pre-compressing the core prior to injection. This pre-compression can be done before, during, or after the injection process. These systems are modular, so the opposing half of the mold is not required to be in constant contact with the core.

When designed correctly, the Side-action mould allows reasonable over-capacity. It can also provide a wide operating window. The Side-action system can be retrofitted into existing moulds and cylinders. It can be fitted externally or reach inward to preload the slide. This minimally-invasive approach can improve the mould's performance and reduce costly rework.

Quick-change mechanism
Quick-change mechanism for LFT mould comprises separable mould members and mould carrying plates. The mold carrying plate is provided with a clamping means for engaging the adapter plate. The clamping means allows the mold half to be selectively opened and closed. In a preferred embodiment, the clamping means is a locking finger.

Quick-change mechanism provides a simple, fast and accurate way of changing a mould. The process of changing a mould is more efficient as the new mold is automatically inserted and the old one is removed. Quick-change mechanism also allows the changeover process to take the shortest time possible, because the material for the new part is already in the mold.

A quick-change mechanism is an important tool for injection molding machines. This system enables the mold to be changed in less than ten minutes. Its quick-change mechanism is a new generation quick-lock system. It eliminates the problems associated with previous quick-lock systems. The new quick-change system also provides a fast method of mounting a new mold without using fasteners or projections.

Critical tilting momenta
Critical tilting momenta are required when mould pressure is high internal mould pressure is required. In addition, critical tilting moments are also required if the part structure is complex. In such cases, a frame press is required with closed loop platen parallelism control. In addition, the LFT mould design has the benefit of being a flexible and lightweight mould.

The critical tilting momenta of an LFT mould are determined from the position of the parisons in the mold. The parisons may be trimmed before complete mold closure and may occur during a phase shift with respect to lead cavities. Furthermore, the parisons may contact the support 18 radially inside if the cut angle is not present.

Material flow
In a typical LFT mould, the material flow is governed by a number of variables, including the initial charge, mass, and fibre orientation. The material mass is typically 293 g for PP-GF40 and 353 g for PP-GF60. The closing speed of the mould is around 10 mm/s.

The material is partially polymerized and has a consistency similar to dough. The lower half of the mould receives the resin charge, and the material flows to fill the cavity. However, it should be noted that the material flow length should be kept within a reasonable range, as too long a flow may cause nonuniform mechanical performance.

The material flow front propagates in a direction that is perpendicular to the wall of the mould cavity. The material flow front propagation can then be calculated through iteration by solving a set of equations based on the initial conditions and boundary conditions. However, due to the instationary nature of the flow process, boundary conditions need to be continually determined, which can take a considerable amount of time.

Bumpoffs
Bumpoffs in LFT moulds can result in parts with internal undercuts that can be deformed during ejection. The ability to bumpoff a part without damaging it is dependent on a variety of factors, including the shape of the undercut, the resin used to form the part, and the design of the mould itself.

One way to avoid bumpoffs is to design an undercut feature that has a ramp-shaped leading edge. This shape will allow the feature to ride over the mould's groove without tearing off the part. On the other hand, if the leading edge of the part is shaped like a hook, it will be lodged in the mould's groove and prevent the part from being ejected.