Pet Preform Injection Moulding Machine.

rakesh_semwal,

It's designed to handle PET, so the barrel is tuned for it, shot size would be pretty large since you'd be running 48-64 cavity molds, tie-bar/daylight opening would need to be big to accommodate the big molds and you'd need plenty of cooling for cycle times. Cooling isn't actually on the machine, but you know that.

And you'd need adequate drying and material handling equipment to support the high thru-put.

lyn Thank you for answering,

Does this mean using a 400 gm shot weight machine for a preform of 10 gm with a 40 cavity mould should work?Of course if those material support systems and auto dryer are incorporated in machine.

I am still wondering if there is something to do with barrel and screw material selection for pet? But I am not sure I tried to search but don't get anything. I Don't want email to any supplier at this point as this may not be real project in future and I don't like suppliers marketing people running after me for their sale.

Hoping to see some more information by morning.

Well,

You'll need to take into account the total shot volume, including the entire runner/sprue system, as well as cavity volume.

If you do general purpose molding, the barrel will be "general purpose". In other words, it will be a compromise to allow the molder to use many different materials in the same machine, so it won't be optomised for any particular material.

Pre form molding is big enough so that manufacturers can tailor a machine to that specific material. The down side is that it may not perform well with other materials if you change over.

Also these machines aren't well suited to smaller shot sizes, due to their larger capacity barrel. A second, general purpose barrel might help here, if the cost and time to change warrants it.

Thank you for your meaningful effort.

For higher volume preforms, the mold stack turret is also an indexable or rotatable cube with the male portions of the mold protruding on four or more sides - the mold closes, and one sent of preforms is molded. The mold opens, and the stack rotates some number of degrees with the warm preforms now pointed at the "ceiling" and new male mold portions ready to go into the female section for the next shot. The process is repeated, again rotating filled forms away and presenting new empty male portions to the mold. By the fourth shot on a 4 set turret, the preforms formed 3 shots ago are ejected straight down to empty the male portions to ready that side of the stack to be inserted at the next cycle.

see

United States Patent 6503075

and

http://www.ptonline.com/articles/npe-news-wrap-up-injection-molding

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In this way, the cooling cycle which is usually the weak link can be extended and the overall rate of the machine increased -

just our two cents

Skippy and Buzz

http://skippyandbuzz.blogspot.com/

eagertask Thank you for reply, Information is appreciated. GA