D.I.P - Direct Injection Process

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Date Submitted: 05/19/2014 10:15 AM

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Selection of Polyurethane

Consider the requirements which the application will demand of the PU with respect to chemical and physical properties.

Based upon an understanding of what controls these properties select a few PU systems.

The properties of a PU are largely controlled by the chemical nature of the system and how it is processed so it is prudent to consult specialist suppliers and processors at this stage.

Direct Injection Process (DIP) PU

The PU, in liquid form is Injected into the closed mold (holding the upper) at high pressure. Thus we get the term “Direct Injection Moulding”

The PU hardens and permanently fuses into one piece with the upper. There is absolutely no chance of separation.

Direct injection moulding or Direct Moulding points to the fact, that the soles are moulded directly onto the upper without use of adhesives or stitching.

This is possible because of the dramatic speed at which monomers polymerise to form network polyurethane, a process that is so rapid, that articles may be fabricated by injecting the reacting monomers directly into a mould.

High Mixing speed of over 18000 RPM resulting in better grain structure and thus better physical properties.

PU Direct Injection Process Moulding Machine

“PU Direct Injection Process Moulding (DIP-PU) Machine”

PU Pouring Technology

As the name suggest this technology uses the method of pouring the liquid mixture into an open mould.

PU Pouring Head

“PU Pouring Head”

The basic principle involved in this technology is the mixing of two liquid chemicals, Polyol and Isocyanate, using a mixing head and pouring the liquid mixture at low pressure into an Open Type Aluminum Mould, thereby PU remains in open condition for sometime.

With P.U. pouring technology, there are two options:

One, where the mixing head is stationary, and the mould-holders move (Conveyor Type Fabricated Mould Holders or Rotary Machine); these machines normally have 32, 40, 60, 90...