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BJY PET Mold Core

Product introduction

The PET preform mold core is the steel part that forms the inside of a preform: the bore and the inner face of the neck, while the cavity shapes the outside.It sits in the PET injection molding system and has a second job beside forming — it takes heat out of the part from the inside.

Product Detail

Item	Detail
Product name	PET Preform Mold Core
Application stage	PET injection molding system (injection stage)
Material	Premium precision mold steel
Part weight	57 g (as quoted for this enquiry)
Dimensions	49 × 258.76 mm for this enquiry. The applicable drawing needs to be confirmed before ordering.
Forming surface	Forming surface polished to mirror level.
Heat treatment	Professional vacuum heat treatment to balance surface hardness and core toughness.
Intended industry	PET packaging production lines for bottled water, carbonated beverages, juice, and other beverage products.
Manufacturer	Foshan Baijinyi Precision Technology Co., Ltd. (BJY), Sanshui District, Foshan City. Established in 2011.

A preform core is small. Ours weighs 57 g. Ask what it is made of and the answer is quality mold steel. The choice of grade is where a good deal of the working life of the part gets settled.

What the grade does on the machine

Steel for this work is picked for how it behaves on the machine. A grade that cuts cleanly lets us hold the form on the drawing from the first part instead of chasing it across a batch. That matters when the same core is ordered again a year later, because the second one has to match the first one. It also matters to a tool room, where a part that needs adjusting before it fits costs an afternoon. A core that has to be reworked after delivery is a small disaster for everybody involved, and most of that is avoidable at the buying stage.
How wear arrives

The next question is wear. PET passes the core face on every shot, and nothing keeps its original surface forever. Steel decides how that change arrives. Slow change can be planned around and written into a maintenance list. Fast change usually shows up as scrap, at a moment nobody chose. Some grades hold up better than others under that treatment, and the difference never appears on a price list.
The same stock, order after order

Material also has to be consistent. We buy to a stated specification and machine in our own workshop in Foshan, so the stock we start from is the same from one order to the next. The machinist who runs the job gets the same cutting behaviour every time. There is nothing clever in that. It just removes one source of surprise from the customer side.
Repeat orders on the same drawing

BJY has supplied PET liquid packaging customers since 2011. Cores leaving our workshop follow the drawing agreed with the customer, and the same drawing is used when the part is ordered again, whether that is six months later or three years later.

BJY PET Mold Core

Product Detail

What the grade does on the machine

How wear arrives

The same stock, order after order

Repeat orders on the same drawing

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