Design points of blow moulds and main accessories
The mold usually only has a cavity part without a punch. Generally, the surface of the mold does not need to be hardened. The inflation pressure of the cavity is much lower than that of injection molding, generally 0.2~1.0MPG, and the cost is lower.
1. Mold material
It is usually made of aluminum alloy, and for corrosive compounds such as PVC and POM, beryllium copper or copper-based alloys are also used; for molds with high life requirements, such as blow-molded engineering plastics ABS, PC, POM, PS, PMMA etc. need to use stainless steel to make molds.
2. Key points of mold design
1) Parting surface Generally, it should be placed on the symmetry plane to reduce the blow-up ratio, such as oval-shaped products, the parting surface is on the long axis, and the distance-shaped products pass through the center line.
2) Cavity surface
The PE material should be slightly rough, and the sand surface is conducive to exhaust; while other plastics (such as: ABS, PS, POM, PMMA, NYLON, etc.) blow molding, the mold cavity generally cannot be sandblasted, and it can be used in the mold cavity. Make an exhaust groove on the parting surface or make an exhaust hole on the cavity. Generally, the vent hole on the cavity has a diameter of φ0.1~φ0.3 and a length of 0.5~1.5mm.
3) Cavity size
The design of the cavity size should consider the shrinkage rate of the plastic. For details, please refer to the shrinkage rate of common plastics. You can click on the blue link to view: →Compendium of Shrinkage Rates of Common Plastic Materials
4) Cutting off the cutting edge and tailing trough
Generally, for blow-molded engineering plastics and harder plastics, the cutting edge should be made of materials with good wear resistance, such as beryllium copper, stainless steel, etc.; for soft plastic products such as LDPE and EVA, generally Aluminum alloy is fine;
The cutting edge should choose a reasonable size. If it is too small, it will reduce the strength of the joint. If it is too large, it will not be able to cut and the jaws at the parting surface will be large. A tailing groove is opened under the cutting edge, and the tailing groove is designed as a clamp. Angle, a small amount of melt can be squeezed into the joint when cutting, thereby improving the strength of the joint.
5) Injection blow mould
The design is different from the extrusion blow molding. The main difference is that the injection blow mold does not need a cutting edge and a tailing trough. The parison design of the injection blown part is very important, which is directly related to the quality of the finished product.
DAWSON MACHINERY & MOULD GROUP
***EXTRUSION BLOW MOLDING MACHINE EXPERT***
Our customers are all around the world.
Vietnam, Australia, Indonesia, Malaysia, Thailand, Sri Lanka, Kazakhstan, Russia, UAE, Saudi Arabia, Malta, Romania, Italy, India, Syria, Ethiopia, Egypt, Sudan, Tunisia, Algeria, Kenya, Nigeria, South Africa, Zimbabwe, Mexico, Guatemala, Ecuador, Colombia, Venezuela, Peru....
Blow Molding Machine Mould/ Injection Molding Machine Mold
| Auto-deflashing | √ |
| Without auto-deflashing | |
DAWSON MACHINERY & MOULD GROUP
High Grade Blowing Molding Mould
In the blow molding process, blow molding mold is an essential and important part. A good blow molding mold makes the molding more smooth, the finished product more beautiful and smooth, and reduces the influence of burr on the appearance and use of the product.
About mould material:
* Steel S50C#: Basic material for blowing moulds, competitive price
* Steel P20#: Common blow molding mould material, medium quality
* 2316 stainless steel: High quality mould material stainless steel.
* S136H : High quality blow molding steel, very durable and strong.
* Aluminium 7075# inserted beryllium copper: the best blow molding mould material,
aluminium mould has good cooling, and beryllium copper is very durable as well.
Dawson engineer team has more than 16 years of experience in blow molding industry. Our blow molding products include scraping lubricating oil bottles, daily chemical products bottles, cosmetics bottles, chemical barrels, auto parts, etc; There is not only a professional team, but also a highly configured production workshop to provide customers with the highest quality blow molding molds and complete plastic products solutions, including blow molding machines, auxiliary machines and automatic packaging lines.
| 1. Mould cavity & Cutting edges use high quality Stainless steel S136H, which is the best material for blowing moulds. |
| 2. Our necking plate is using imported JAPAN material DC53,Heat treatment to HRC62. |
| 3. Our cooling system is covered very average,all the necking area, handle area had designed perfect cooling system to make sure long time smooth running. |
| 4. Our de-flashing unit and mask material is using High quality Aluminium alloy 6061#. |
| 5. De-flashing cylinder all use high quality Taiwan AIRTAC cylinder. |
Our Professional Plastic Molding Mold Workshop...
