Double Injection Mold
Double injection mold is known as 2 material 2 shot mold or 2K mold. Double injection mold is an innovative manufacturing process used to produce complicated molded parts from two different materials.
Double injection mold is programmed to perform two injections in one cycle. Double injection mold uses a nozzle to inject plastic into a mold in the first cycle.
Double injection mold would automatically be rotated and inject another plastic in from a second nozzle. Double injection mold optimizes co-polymerization of hard and soft materials to create a powerful molecular bond.
Automotive injection mold
Automotive injection mold is popular and widely used. Automotive injection mold is lightweight, easily made and very durable.
Automotive injection mold could make mass production simpler and much more cost efficient. Automotive injection mold is used to make general instrumentation, including the mold that holds it all in place, housings for electronic module controls and radio controls.
Automotive injection mold includes manufacturing of exterior plastic automotive components like louvers, paneling, and railing, bumper support, fender, mudguards, door locking systems.
ABS Injection Mold
ABS injection mold uses acrylonitrile-butadiene-styrene as the injection material. It is commonly used in mechanical and electrical applications.
ABS’s light weight and ability to be injection molded and extruded make it a helpful plastic mold in many industries like medical devices, electrical and electronics, hardware, enclosures, business machines and computer housings, industrial parts, appliances, automotive and so on.
The most important mechanical properties of ABS are impact resistance and toughness. For the majority of applications, ABS can be used between −20 and 80 °C (−4 and 176 °F) as its mechanical properties vary with temperature. It can withstand high temperatures and high impact situations.
Hot Runner Mold
Hot runner mold is mold with a hot running system. It consists of two plates heated with a manifold system. A hot runner system is a molten plastic conveying unit used within an injection mold.
Hot runner mold can maintain a consistent temperature in the runner. It is usually connected to needle valve nozzles and activated with the precise computer. Hot runner mold is often used as multi-cavity molds. It has gates at the best position for economical design.
Hot runner mold has many advantages. It is suitable for big parts. Hot runner mold can improve production efficiency.
Contact Us For Your Injection Mold Project
Five-Star yearly capability is up to 500sets mold per year, the biggest reach 20 tons, and the largest size is 2.5m x 2.5m.
Five-Star has a full set advanced mould manufacturing equipment, 6 sets CNC machines, 13 sets EDM machine, 3 sets middle-speed wire cut machine, 2 sets slow speed wire cut machine, 13 sets milling machine, 3 sets lathe machine, 2 sets mold die fitting machine, 8 sets injection machine from 60 tons to 470 tons.
Check here to study more about Five-Star Tooling.
Chapter 1: The Introduction of the Injection Mold
There is a close relationship with all kinds of mold, which are referred to our daily production, and life in the use of the various tools and products, the large base of the machine tool, the body shell, the first embryo to a small screws, buttons, as well as various home appliances shell.
Mold’s shape determines the shape of these products, mold’s precision and machining quality determine the quality of these products, too.
1.2 Mold general definition
In the industrial production, with the various press and the special instruments which installed in the press, it produces the required shape parts or products through pressure on the metal or non-metallic materials, this special instruments collectively call as the mold.
1.3 Mold general classification
Mold can be divided into plastic and non-plastic mould
1) Non-plastic mold
a. Die casting
b. Forging dies
c. Die computer panel
d. Die casting
2) For production technology and production, plastic molds are divided into different products:
a. Injection molding
b. Inflatable mould
c. Compression molding
d. Transfer molding
e. Hot forming die
f. Rotomoulding mode
Injection molding is the most popular method in plastics producing process. The method can be applied to all parts of thermoplastic and some of thermosetting plastics, the quantity of plastic production is much more than any other forming method.
Injection mold as one of the main tools of injection molding processing, whose production efficiency is low or high in the quality of precision, manufacturing cycle and the process of injection molding and so on, directly affect the quality of products, production, cost and product updates, at the same time it also determines the competitiveness of enterprises in the market’s response capacity and speed.
Injection mold consists of a number of plates which mass with the various component parts. It divided into:
a. Molding device (die, punch)
b. Positioning system
d. Cooling system
e. Thermostat system
f. Road system
g. Ejection system
1.4 type of mold
it can be divided into three categories according to the gating system with the different type of mold:
1) intake mold: runner and gate at the parting line, it will strip together with products when in the open mode, it is the most simple of design, easy processing, and lower costing.
So more people operations by using large intake system
2) small inlet mold: it general stay in the products directly, but runner and gate are not at the parting line. Therefore, it should be to design a multi-outlet parting line.
And then it is more complex in the designing, more difficult in processing, generally choosing the small inlet die is depending on the product’s requirements.
3) Hot runner mold: it consists of heat gate, heat runner plate, temperature control box. Hot runner molds are two plate molds with a heated runner system inside one half of the mold.
A hot runner system is divided into two parts: The manifold and the drops. The manifold has channels that convey the plastic on a single plane, parallel to the parting line, to a point above the cavity.
The drops, situated perpendicular to the manifold, convey the plastic from the manifold to the part.
The advantages of hot runner system:
a. No outlet expected, no need processing, the whole process fully automated, save time and enhance the efficiency of the work.
b. Small pressure loss
Chapter 2. Injection Mold
There are many rules for designing molds. These rules and standard practices are based on logic, past experience, convenience, and economy.
For designing, mold making, and molding, it is usually of advantage to follow the rules. But occasionally, it may work out better if a rule is ignored and an alternative way is selected.
In some texts, the most common rules are noted, but the designer will learn only from experience which way to go. The designer must ever be open to new ideas and methods, to new molding and mold material that may affect these rules.
The process consists of feeding a plastic compound in powdered or granular form from a hopper through metering and melting stages and then injecting it into a mold.
Injection molding process: mold is a production of plastic tool. It consists of several parts and this group contains forming cavities.
When it injects molding, mold clamping in the injection molding machine, melting plastic is injected forming cavities and colling stereotypes in it, then it separate upper and lower die, it will push the production form the cavity in order to leave the mold through ejection. The entire process of injection is carried out of the cycle.
An injection mold consists of at least two halves that are fastened to the two platens of the injection molding machine so that can be opened and closed.
In the closed position, the product-forming surfaces of the two mold halves define the mold cavity into which the plastic melt is injected via the runner system and the gate.
Cooling provisions in the mold provide for cooling and solidification of the molded product so that it can be subsequently ejected.
For product ejection to occur, the mold must open. The shape of the molded product determines whether it can be ejected simply by opening the two mold halves or whether undercuts must be present.
The design of mold is dictated primarily by the shape of the product to be molded and the provisions necessary for product ejection. Injection-molded products can be classified as:
1) Products without undercuts
2) Products with external undercuts of lateral openings
3) Products with internal undercuts
4) Products with external and internal undercuts
Chapter 3: The Composition of Injection Mold
3.1 Mold Cavity Space
The mold cavity space is a shape inside the mold, when the molding material is forced into this space it will take on the shape of the cavity space. Injection molding the plastic is injected into the cavity space with high pressure, so the mold must be strong enough to resist the injection pressure without deforming.
3.2 Number of Cavities
Many molds, particularly molds for larger products, ate built for only 1 cavity space, but many molds, especially large production molds, are built with 2 or more cavities.
The reason for this is purely economical. It takes only little more time to inject several cavities than to inject one. Today, most multi-cavity molds are built with a preferred number of cavities: 2, 4, 6, 8, 12, 24, 32, 48, 64, 96, 128.
These numbers are selected because the cavities can be easily arranged in a rectangular pattern, which is easier for designing and dimensioning, for manufacturing, and for symmetry around the center of the machine, which is highly desirable to ensure equal clamping force for each cavity.
3.3 Cavities and Core
By convention, the hollow portion of the cavity space is called the cavity. The matching, often raised the portion of the cavity space is called the core.
Most plastic products are cup-shaped. This does not mean that they look like a cup, but they do have an inside and an outside. The outside of the product is formed by the cavity, the inside by the core.
Usually, the cavities are placed in the mold half that is mounted on the injection site, while the cores are placed in the moving half of the mold.
The reason for this is that all injection molding machines provide an ejection mechanism on the moving platen and the products tend to shrink onto and cling to the core, from where they are then ejected.
Most injection molding machines do not provide ejection mechanisms on the injection site.
For moulds containing intricate impressions, and for multi-impression plates from single blocks of steel as with integer moulds.
The cavity and core plates from single blocks of steel as with integer moulds. The cavity and core give the molding its external and internal shapes respectively, the impression imparting the whole of the form to the molding.
3.4 The Parting Line
To be able to produce a mold, we must have at least two separate mold halves, with the cavity in one side and the core in the other.
The separation between these plates is called the parting line and designated P.L. Actually, this is a parting area or plane, but, by convention, in this intext, it is referred to as a line.
The parting surfaces of the mold are those portion of both mold plates, adjacent to the impressions, which but together to form a seal and prevent the loss of plastic material from the impression.
The parting line can have any shape, many moldings are required which have a parting line which lies on a non-planar or curved surface, but for ease of mold manufacturing, it is preferable to have it in one place.
The parting line is always at the widest circumference of the product, to make ejection of the product from the mold possible, with some shapes it may be necessary to offset the P/L, or to have it at an angle, but in any event it is best to have is so that it can be easily machined, and often ground, to ensure that it shuts off tightly when the mold is clamped during injection.
If the parting line is poorly finished the plastic will escape, which shows up on the product as an unsightly sharp projection, which must then be removed; otherwise, the product could be unusable. There is even a danger that the plastic could squirt out of the mold and do personal danger.
3.5 Runners and Gates
Now, we must add provisions for bringing the plastic into these cavity spaces.
This must be done with enough pressure so that the cavity spaces are filled completely before the plastic “freezes”(that is, cools so much that the plastic cannot flow anymore).
The flow passages are the sprue, from where the machine nozzle contacts the mold, the runners, which distribute the plastic to the individual cavities, the wall of the runner channel must be smooth to prevent any restriction to flow.
Also, as the runner has to be removed with the molding, there must be no machine marks left which would tend to retain the runner in the mold plate.
And the gates which are small openings leading from the runner into the cavity space. The gate is a channel or orifice connecting the runner with the impression.
It has a small cross-sectional area when compared with the rest of the feed system. The gate freezes soon after the impression is filled so that the injection plunger can be withdrawn without the probability of void being created in the molding by suck-back.
Chapter 4: What Products Can Be Made from Injection Mold?
When creating a product that requires molded plastic parts, depending on the type of application and type of part you want to produce, you have several processes to choose from.
One of the most popular processes to achieve high quality and cost-effective plastic parts is injection mold.
Injection mold is a manufacturing process for producing parts in large volume – from thousands to millions. The melted resin is injected into a hollow mold until it is completely filled.
The injection mold process uses high temperature and extreme pressure to sufficiently fill the interior with molten plastic resin or liquid polymers. The molds are then cooled to release completed plastic parts.
The process is highly versatile and can produce a myriad of parts for a wide variety of applications.
Typical Products Made with Plastic Injection Mold
Other consumer electronic components
Machinery and Automotive Components:
Many other interior and exterior elements
High-end Trash and Recycling Receptacles
Vending Machine Components
Sharps Disposal Bins and Wall Mounts
Conduits for Concrete Beams
Raised Flooring Panels
Skateboard Storage Racks
Toys and Hobbies:
High-end Collectible Models
Decorated Children’s Furniture
High-Temperature Serving Pans
NSF Food Service Products
Short-Run 3D Printed Components:
Chapter 5: How Does Injection Mold Work?
Injection molds must have a high precision match between the two mold halves in order to perfectly control the material flow. Creating the mold is crucial to building a seamless, precision product.
Injection molds are typically constructed using steel or aluminum, and precision-machined to form the features of the desired product.
The injection mold process is fairly repetitive once a functional, errorless mold has been produced.
It also has a low scrap rate relative to other manufacturing processes such as CNC machining which cut away considerable portions of the original material blank in a subtractive process.
The Injection mold process is highly repeatable and reliable for high volume production. Once the first part is produced, the second is going to be practically identical, due to the ability to make multi-cavity injection mold parts, where multiple parts are made with one cycle.
Other advantages are the wide range of material selection, low labor costs, minimal scrap losses, and minimal requirements for post-mold finishing operations.
The major disadvantages of injection mold are the initial costs of the mold design, which tends to be high due to design, testing, and tooling requirements and the longer required lead times.
Some custom complex parts may encounter problems during the injection mold process such as warpage or surface defects. Therefore, injection molded parts must be designed with careful consideration of any change in geometry as they cool and the material selection to assure stability.
The process of injection mold may seem like a complex one, but it’s the most common manufacturing method because of its capability and efficiency to produce a plethora of everyday items.
Injection mold is one of the most cost-effective ways to build both functional prototypes and end-use products.
Questions? Look Here.
1、Q：Do you have the experience to build export mold?
A：Yes, we do. Over 95% of our molds are exported.
2、Q：How many moulds could you make every month?
3、Q：How many employees do you have?
4、Q：How about the largest mould you can make?
A：20 ton. The size is 2.5m x 2.5m.
5、Q：What is the percentage of automotive molds you made? What’s the brand?
A：About 35%. Brand: BENZ, VW, GM, FORD, TOYOTA, NISSAN. Lamborghini
6、Q：Can you make precision mold?
A：Yes. And we can hold mould tolerance +/- 0.01mm, product tolerance +/- 0.02mm.
7、Q：How about the steel you usually use?
A：We only use raw materials with good quality like P20,
P20H, 718H, NAK80, 1.2311, 1.2378, 1.2344,1.2343 ESR, 1.2767, H13, 8407, 420SS, S136, S-7,etc. They are all from famous suppliers, such as LKM, ASSAB, THYSSEN, etc.
Steel certificate and heat-treatment certificate will be provided along with the tools while delivery if required.
8、Q ：What is the standard of your hot-runner system？
A：It’s decided by the customers. We have famous hot runner suppliers locally, such as MOLD MASTER, INCOE, YUDO, DME, SYNVENTIVE, HUSKY, HASCO, EWIKON, GUENTHER, etc.
9、Q：What kind of standard components do you use?
A：HASCO, DME, PROGRESSIVE, STAUBLI, RABOURDIN are available.
10、Q：What do you need for quotation? And what about the software?
A：2D & 3D part files and mold specifications are preferred. We mainly use UG and AUTOCAD. But it is OK, for us to read the files of Solid works, PRO-E and Catia, etc.
11、Q：What is your turnover in 2017?
A：About 9 million USD.
12、Q：What is your turnaround time for injection mold building?
A：Usually 3 to 8 weeks. It also depends on mould size and structure complexity
Five-star Tooling now occupies a land area of 6000 square meters.
With high-precision grinding machines, wire cutting, CNC, EDM, CMM, and other manufacturing and inspection equipment, we can keep tolerance of +/- 0.005mm.
As an ISO 9001:2015 certified company, we take the high quality as a base for the companies’ development, from incoming material to electrode, from CNC machining to final assembly, every component and every process needs to be strictly inspected by QC, to ensure every component is accepted before the next process.
- Multi-cavity (Up to 128 cavities)
- Collapsible Cores
- 2-Shot Molds
- Stack Molds
- Hot runner system ( Mold Master, Incoe, Husky, Syventive, YUDO)
- Large and Complex Moulds (Up to 20 ton.The size is 2.5×2.5m)