How to choose Injection Mold Tooling?

Is injection mold tooling very helpful? What are the advantages of it compare to other manufacture method?

This article introduces the advantages and disadvantages, key points for selecting, and lifespan of injection molding tools.

To assist someone that has demand for parts production like yourself, able to better understand the broad application of injection molding technology.

What is Injection Mold Tooling used for?

Injection mold tooling utilizes injection molding technology, by injecting the raw materials into a mold, which forms into the desired shape of the parts.

It is widely applied in production of plastics and metal components. These kinds of molds must have high strength and precision to meet the demands of large scale production.

Further reading : Injection Mold Design, Your Customized Parts!

What are the advantages of Injection Mold Tooling? Are there a lot of disadvantages?

Injection mold tooling has 7 advantages, but just like every other manufacturing process, it also has some drawbacks.

This article will comprehensively give the overview of the advantages and disadvantage, helping you quickly assess whether injection molding is the optimal production method.

Once a mold is designed and put into use, it can consistently produce countless batches of identical parts with high precision and uniformity.

This is especially beneficial for large scale production of precision and reliable parts, ensuring that every product follows a strict design specifications and minimizing the problem of having different quality between batches.

Compared to other manufacturing processes (such as traditional Lathe Machining), which generates significant amounts of non-recyclable metal or plastic scraps, injection molding uses materials more precisely, resulting in reduction of excess waste.

Even if there is excess plastic or waste generated, it can be efficiently recycled and reused, which further minimizes material loss and reduce the impact on environment.

Once the development of the injection mold tooling is complete, the production process can be extremely fast, handling demands flexibly from 10000 to over 100000 parts depending on the mold type.

If multi cavity or family mold is applied, it can further enhance production efficiency, allowing one machine to produce multiple parts simultaneously, which significantly speeds up production.

Able to choose from various plastic types that are most suitable based on the specific requirements of the final parts.

Besides common resin materials, there are also options like liquid silicone rubber, which offers greater flexibility in product design.

Additionally, adding fillers to the materials can enhance the strength and durability of the parts, and combine with various color options, it can meets the different demand for performances and appearances,  achieving various target design.

Since the process involves injecting molten plastic into the mold under extremely high pressure, it can ensure the plastic to tightly fill every detail and corner of the mold with the mold designs capable to lower its precision down to Micro level.

So that even highly complex and detailed parts can be perfectly replicated. This is suitable for various industries that require high precision and complex design application such as automotive and electronics.

When producing in larger volumes, the initial investment in the mold can be quickly amortized, which can drastically reduce the per-part production cost.

Even for medium scale production, aluminum molds can also be used to further lower costs, as they are generally more cost effective than steel molds while still meeting production demands.

Since in design and manufacturing stage, the mold already has a high precision, the parts produced often has excellent surface quality and appearance, so it significantly reduce the need for post-processing.

Through special surface treatment, such as smooth, rough or textured, or adding some details such as logos or text, it can directly reflects on the final product of the Mold, achieving the appearance demanded.

If using steel molds, production time will be longer and process is more complex, which will require large amount of capital investment for large scale production.

If only require smaller production scale, this high cost will significantly increase the price per part

Injection mold tooling has certain design constraints, such as wall thickness, transitions, and parting lines, which can affect parts removal and quality.

Also, once a mold is designed, making modifications later can be challenging and costly.

Due to the high upfront cost for mold creation, it is difficult to amortize these costs for small scale production.

Even though the production costs for the parts themselves are low, but the high investment makes the small scale production expensive, which drives up the unit price of each part.

Steel molds can take weeks to manufacture, which potentially delaying overall project timelines.

For projects that require rapid production, this might be a problem that is challenging to overcome, to not be able to have mass production in a short period of time.

Overcoming these disadvantages is actually not overly complicated. Just simply communicate your needs to the manufacturer, and they may suggest alternatives like aluminum molds instead of steel, or employ 3D printing and CNC machining as solutions.

These options can not only shorten production cycles, but also provide cost effective results, which can also demonstrates the manufacturer’s expertise and professionalism, ensuring to offer the most suitable solution for your needs.

What are the types of Injection Molding Tools? Where can it be applied?

Injection molding tools come in various types, each designed for specific uses depending on factors such as production volume, parts complexity, and material characteristics.

Here are the 7 types of injection molds, their applications, and the situations they are best suited for.

A single-cavity mold design has one cavity and can produce only one part per injection cycle. Its simplicity makes the mold development and production process easier, which reduce costs and shortening lead times.

This is ideal for low production volumes or custom projects where each part may have unique requirements.

It is also practical for large parts, because combining multiple cavities in one mold might be unrealistic due to size and machine capacity constraints.

For example, medical equipment production, including customized syringe casings or instrument housings, has a unique requirement for its size and function, and need to ensure its quality and precision.

A multi-cavity mold contains multiple identical cavities, allowing it to simultaneously produce multiple parts every injection cycle, which can boosts production efficiency and output.

Even though this kind of mold can satisfy the needs for rapid large scale production, but must ensure that the cavity filling, cooling, and ejection is even to maintain parts quality in the designing process.

It is suitable for industries that require mass production of identical components, such as electronic device casings or accessories, or packaging products like bottles and caps.

nsert molds is placing the pre-made metal embeds into the mold before injecting molten plastic. This allows the plastic to bond tightly with the metal embeds, forming a strong integrated structure. The precision in placing embeds and controlling the injection process is critical.

This is suitable for applications requiring a combination of metal strength and plastic flexibility, such as the production in medical devices or automotive components.

Its advantage is to be able to effectively combine different characteristics of materials, achieving the dual demands of function and design.

A prototype mold is a simpler and more economical tool made from less durable materials, so it is not suitable for long term or large scale production.

Instead, it is used for smaller scale production to quickly evaluate the design, functionality, and feasibility of a parts before investing in full scale production.

In an early stage of product development, prototype molds are widely used across industries for design verifications and testing, such as electronics, automotive, and medical fields, where designers will use the prototype mold to test different shapes and functionalities of casings design, ensuring the final product can meet the market demands and user expectation.

Stack molds consist of multiple parting surfaces that allow individual production of one part on each surface in a same injection cycle.

This design can double or even triple the output of traditional single face molds without the need to increase machine size or changing clamping requirements, which efficiently increase production ability.

This is suitable for large scale production where the space or equipment is limited, such as for small parts like packaging materials or disposable medical devices.

Over molding mold involves injecting different materials in layers to create multi layered parts.

One material will be injected first as the base, then another is injected in subsequent cycles to cover or surround the base, which can make the final product to have soft exterior or multiple colors and textures.

This is suitable in use for enhancing both the functionality and aesthetics of products. For example, to produce a firm internal structure and a soft outer surface for a better grip of a basketball, or widely used in home appliances by adding a non-slip rubber layer to the housing to enhance user experience.

A family mold allows for the production of different parts in a single injection cycle, which makes the requirement for the design higher since each cavity might need different volume. This will also require precise balancing to ensure consistent quality across all parts.

Family molds are suitable for the needs of producing multiple components that will be assembled into a final product, especially when the demand for each component is similar, it can reduce the dependency for many molds, simplifying the whole manufacturing process.

For example, in the production of home appliances, a family mold can simultaneously create the control panel, buttons, and housing for a coffee machine.

Further reading :Why do we need custom injection molding?

How long is the lifespan of Plastic Injection Mold?

PLASTICS, formerly known as Society of the Plastics Industry (SPI), categorizes injection mold tooling into 5 major classes, which not only provide a convenient method for comparing mold output and production cycles, but also assisting to analyze the overall lifespan and functionality.

This help companies in understanding the reliability and adaptability of different molds over long term use.

What factors will affect the lifespan of Injection Molding Tools?

To extend the lifespan of injection molds, even for those intended for small scale production, the following 6 key factors can be optimized to maximize the durability:

Manufacturer

If the manufacturer lacks precise temperature control or fails to adjust the clamping force correctly, molds can be damaged due to the high pressure and heat.

While excessive clamping force can lead to over-stressing the mold, which will accelerates its wear. Similarly, operational errors such as premature opening of vents or clamps before the mold has cooled down, can also cause damage.

So, mold lifespan relies heavily on the manufacturer’s expertise. Maintaining accurate control of the temperature and proper operational procedures can significantly improve mold durability and product consistency.

Further reading : How to find Plastic Injection Plant？

Mold Materials and Characteristics

Mold material generally fall into 3 categories; Aluminum, Soft/Half-Hardened Steel, and Hardened Steel. Aluminum molds are suitable for small scale production, due to its shorter lifespan, but the lifespan might drastically increase by using a harder aluminum like the 7000 series.

Once the product demands are larger, using half-hardened steel mold like P20 or 718H is not a bad choice, which can balance out between the strength and process ability, supporting more than 10000 injections.

When a larger scale production is needed, Hardened Steel like H13 or S136 are more suitable, with its outstanding wear resistance and heat resistance, capable to handle long term large scale production, and effectively resist wear.

When the mold requires multiple sideways movement or embedding metal components, more durable hardened embedding can be used in specific areas to further enhance the durability of the mold.

Usage Environment

When molds process in harsh environments, like dusty, humid or in a workshop with corrosive substance, it will easily be vulnerable to contamination, resulting in parts wear and performance degrading, with addition to acceleration of molds wear and reduce of accuracy and durability.

Or when the mold is not used under appropriate condition according to the design specifications, for example operating under high temperatures or pressures, can also lead to material fatigue or deformation, which reduces their lifespan.

Cleaning and Maintenance Periodically

Must avoid using abrasive cleaners during cleaning, as they may damage the surface or protective coatings of the surfaces.

While for moving parts like ejector pins and slides, it require an appropriate amount of lubrication, but keep in mind that over-lubrication can attract dust and increase wear.

Regular inspection and preventive maintenance are also crucial, including occasional shutdowns for repairs.

Keeping maintenance records can help identify issues early and minimize unnecessary downtime, ultimately extending mold lifespan and ensure the production efficiency.

Material Selections

Using abrasive materials like glass filled resins might accelerate mold wear, while some corrosive materials like PVC and POM can severely damage aluminum molds. Opting for hardened steel molds such as S136 can better resist corrosion from such chemicals.

Mold and Parts Design

Using modularized mold designs can simplify the maintenance procedure by making the replacement of worn parts easier, without needing to replace the entire mold.

Additionally, thickness design of the parts also needs to be payed attention, because thicker wall parts often require longer cycle times, which can lead to accelerated mold wear.

Why choose plastic injection mold tooling?｜FAQ

Plastic Injection Mold Tooling Exporter | Hsin Hung Yih Plastic

When it comes to controlling costs and extending the lifespan of molds, choosing the right manufacturer is crucial. If you are not sure where to start or are concerned about the manufacturer’s experience and expertise, it is recommended to seek assistance from Hung Yih Technology, or Hsin Hung Yih Plastic.