PET Blow Moulding Machine

Product Details:

 

What is Blow Molding?

Blow molding started in the glass blowing industry where a liquid glass pulp is enclosed in a two-piece mold and then expanded by blowing into to the pulp.

With the invention of polymeric thermoplastics, this technology started to rev up in the plastic bottle industry.

The outcome isn’t exactly good for the environment, but if you use biodegradable materials or recycle thermoplastic bottles made from PET, things look a bit better.

Blow Molding versus Injection Molding

So, what’s the difference between parts made by injection molding and parts made by a blow molding machine? Injection molding creates solid parts, while blow molding creates hollow parts.

If you are looking for something that needs only one rigid wall, injection molding is the right process. Think of bottle caps, cases, combs, and housings for computers and televisions.

If you need a flexible, structural piece that even can hold fluid, you’re best off with blow molding. No wonder that billions of water bottles stand for the blow molding technology.

How Plastic Bottles are Made

Producing plastic bottles does not greatly differ from the glass blowing process. The technology used by the bottle forming process is called Injection Blow Molding (IBM). This requires a so-called preform which is much smaller than the actual bottle.

The preform can be transported easily and if variants do not differ in weight it can be used uniformly. Like in the glass manufacturing process, the preform is heated up, put into the mold and inflated.

 Due to the preform, the material expands equally, resulting in a better flow control, surface quality and transparency.

After the blow molding process, the bottle heads have to be threaded and the excess material cut off.

What are the Advantages of Blow Molding?

Blow molding scores especially at mass producing at a low price. Depending on the quality of the mold, it can produce more than over 1 million pieces before it has to be replaced.

The production is also very fast compared to other molding processes, ejecting a finished product every few seconds. Thin walls and water-cooled molds also reduce cycle time.

In addition, once the machine parameters are calibrated, the outputs quality is constant. This is achieved because factoring parameters are stable and controllable.The process of blow molding is also perfect for automation, reducing the need for workers working in a monotone environment.

Technical Specifications of Auto PET Blow Moulding Machine:

1) Production Speed: 1000 / 2000 / 4000/ 6000 / 8500 BPH
2) Neck dia : 28mm suitable for 35 Bar Air
3) Hydraulic Clamping System
4) Infrared Conveyerised Preheating System
5) Four Modules
6) Incremental Heater Settings by 1% to 99%
7) No Preform No Blow
8) Display interface via 320 x 240 graphic display process on line Control. (Mould Memory, Error Memory)
9) Neck Holder: SS 304
10) Hyd. Locking Check Valve for Power Saver

EFPL manufactures excellent quality Automatic PET Blow Moulding Machines for PET bottle production.

Our Automatic PET Blow Moulding Machines have wider wide-mouth capability, faster production rates, and shorter changeover times.

Attributes of Automatic PET Blow Molding Machine:

1) Production Speed: 1000 to 1200 BPH
2) Production Capacity: 50ml to 2000ml
3) Hydro - pneumatic locking system
4) Heating unit Et blowing unit
5) Heating zone adjustable as per the size of preforms
6) Integrated water loading system in blow m/c is also given for better result
7) Weight : 1500 K.G. (Including Heater)
8) Dimensions : L-7ft x W-2.6ft x H- 12ft

 

Product Details:

We have with us rich experience in successfully handling the demands of precision designed and optimally functioning Semi Automatic PET Bottle Blowing Machine - 2 Cavity

Product Details:

Production Process:
Production of PET containers requires injection molding of preforms and subsequent stretching and blowing of these into bottles. Both operations can be combined in one machine (the single-stage process) or in two (the two-stage process). Both processes have their distinct advantages and disadvantages, and bottle producers and brand owners would be well advised to know those in order to make the right choice for their products.
 
The advantages of the single stage are:

• Blemish-free bottles
• Transferring not necessary
• Control over preform production
• Good conditioning possibilities for oblong bottles on some machines
• Thread start can be chosen to coincide with bottle shape;
• Compact and flexible

In my view, these advantages make this process a no-brainer for all non-beverage containers.

However, there are some disadvantages as well, including:

• Long cycle time
• Quality problems with thermal-gated hot runners (valve gates are available and recommended)
• Need to run machines run 24 hr/day to avoid higher scrap percentage
• The longer learning curve for operators, as two processes and PET drying must be mastered
• Inefficient blow station as the injection station always has precedence over the cycle time

The latter issue has led to a subcategory of single-stage machines that I call integrated two-stage machines. These machines feature a multiple of two or three injection cavities per blow cavity, and the blow sections of the cycle two or three times for every injection cycle. This saves blow cavities and thereby reduces tooling costs, a critical issue for small- and medium-volume applications.

The uneven wall distribution is a result of viscous heating of the melt. As the melt moves through the barrel and hot-runner channels it heats up unevenly. When it is then divided into two streams (left and right, typically), warmer material flows to the back of the new channel. If you were to stand in front of the machine you might notice that finished bottles are often thinner at the back because they were blown with warmer material in the back panel.

While PET is very good at self-leveling (the strain-hardening effect that compels initially warmer areas to blow out after cooler areas have blown), this effect is not significant enough to mask the uneven preform heat. A variety of measures have been employed over the years with varying success.

Most hot runners are also not naturally balanced. Natural balance means that the path of the melt to each cavity has the same length and number of turns. Because of geometry—all preforms in one row—this is often not possible, and as a result, preforms do not fill at the same speed, aggravating the problem. Changing nozzle diameters to allow slower-moving melt through larger openings is helpful, but usually can only be optimized for a very narrow weight range. Another solution is to add obstacles in the flow path of the faster-moving cavities.

Thermal-gated hot runners are inferior to valve-gated ones, in my opinion, but most machines still run with the former.

Now let’s look at the advantages of the two-stage process:

• Scalable from 1000 to 72000 bottles/hr
• Fast cycle times
• Fast changeovers
• Flexibility (preforms can be made elsewhere and stored)
• Very good wall distribution for round bottles

Features:

• Hydraulic clamping system
• Infrared conveyorised preheating system four modules
• Incremental heater settings by 1%-99%
• No Preform, No Blow
• Display interface via 320x240 graphics display process online control (mould memory, error memory)
• Hyd. locking check valve for power saver

Additional Information:

• Production Capacity: 1200

Product Details:

We are engaged in offering Automatic Blow Moulding Machine to the clients.

Specification/Additional Details

• Weight1500 K.G. (Including Heater)
• Production Speed1000 to 1200 BPH
• Bottle Capacity50ml to 2000ml

Product Details:

Production Process:
Production of PET containers requires injection molding of preforms and subsequent stretching and blowing of these into bottles. Both operations can be combined in one machine (the single-stage process) or in two (the two-stage process). Both processes have their distinct advantages and disadvantages, and bottle producers and brand owners would be well advised to know those in order to make the right choice for their products.
 
The advantages of the single stage are:

• Blemish-free bottles
• Transferring not necessary
• Control over preform production
• Good conditioning possibilities for oblong bottles on some machines
• Thread start can be chosen to coincide with bottle shape;
• Compact and flexible

In my view, these advantages make this process a no-brainer for all non-beverage containers.

However, there are some disadvantages as well, including:

• Long cycle time
• Quality problems with thermal-gated hot runners (valve gates are available and recommended)
• Need to run machines run 24 hr/day to avoid higher scrap percentage
• The longer learning curve for operators, as two processes and PET drying must be mastered
• Inefficient blow station as the injection station always has precedence over the cycle time

The latter issue has led to a subcategory of single-stage machines that I call integrated two-stage machines. These machines feature a multiple of two or three injection cavities per blow cavity, and the blow sections of the cycle two or three times for every injection cycle. This saves blow cavities and thereby reduces tooling costs, a critical issue for small- and medium-volume applications.

The uneven wall distribution is a result of viscous heating of the melt. As the melt moves through the barrel and hot-runner channels it heats up unevenly. When it is then divided into two streams (left and right, typically), warmer material flows to the back of the new channel. If you were to stand in front of the machine you might notice that finished bottles are often thinner at the back because they were blown with warmer material in the back panel.

While PET is very good at self-leveling (the strain-hardening effect that compels initially warmer areas to blow out after cooler areas have blown), this effect is not significant enough to mask the uneven preform heat. A variety of measures have been employed over the years with varying success.

Most hot runners are also not naturally balanced. Natural balance means that the path of the melt to each cavity has the same length and number of turns. Because of geometry—all preforms in one row—this is often not possible, and as a result, preforms do not fill at the same speed, aggravating the problem. Changing nozzle diameters to allow slower-moving melt through larger openings is helpful, but usually can only be optimized for a very narrow weight range. Another solution is to add obstacles in the flow path of the faster-moving cavities.

Thermal-gated hot runners are inferior to valve-gated ones, in my opinion, but most machines still run with the former.

Product Details:

We are well-known and trusted manufacturers of PET Bottle Automatic Stretch Blow Molding Machine in the market.

Additional Information:

• Production Capacity: 1000 / 2000 / 3600 / 5400 / 7200