The concept of Single Minute Exchange of Die has been around for a while, but for those of us working with a limited budget or a variety of materials (with different processing temperatures), anything under an hour would be nice! There are however some relatively inexpensive changes you can make, without having to result to budget-busting auto-tool change systems and magnetic platens….
‘Hard Piping’
How often have you seen a setters legs dangling out of a locker, as he tries to find a long enough connection hose? ‘Piping up’ a tool from scratch takes time, leads to errors and often results in too many looped circuits. (Machines rarely have enough water gallery circuits). If you go to a Mould Shop Consumables specialist, you can buy pairs of colour-coded aluminium manifolds to suit (i.e. correct number of ports), each side of the tool. These usually have through holes for easy mounting directly onto the tool.
By using cheap 90 degree hose-tails in the manifolds and tool ports, (make sure you match sizes, e.g. ¼” BSP when specifying the manifolds), pipe runs are relatively flat to the tool surfaces. It may be necessary to fit `feet’ to the tool, particularly if water pipe or the manifolds themselves are fitted to their underside.
The inlet to each manifold will be fairly large, ¾ or 1” BSP for example, so good flow is guaranteed. By fitting a large shut off fitting to each manifold, and a matching fitting to the main water supply for that manifold, you prevent the water from draining from the tool / air entering and causing corrosion. There are various styles of these shut off fittings, so you can make sure that the correct connections are made, e.g. in/out or hot/cold.
‘Pre-Heating’
In some cases, time can be saved if you connect any warm water tooling zones to a spare Water Heater in advance of starting a tool change. This operation is simplified if the tool is ‘hard-piped’.
Purging
If you are also changing materials /colours, a good Purging Agent will speed up the process and also reduce scrap rates caused by contamination.
Clamping
Firstly, if your machine platens have T-Slots, use them wherever possible. A set of Lenzkes Clamps with T-Nuts, or even a set of Forged Clamps specified with a stud (threaded both ends), flanged nut and T-Nut will make it easier to secure a tool quickly and effectively.