Most moldflow simulation software is capable to calculate on a very accurate way. The only problem is that the operator must really understand plastics, product design, mold design and what happens in the production. If the operator doesn't have these skills then you get only nice pictures which everybody can make when he knows how to work with the moldflow analysis software. I have the experience that a good mold flow analysis will need enough time and enough different simulations. I really do not understand how most of the simulations are made within one setting. How do you know this is the correct one. Most calculations are made with the simplest cooling circuits and we all know that in the practice this is almost not possible. It is not the moldflow software who determines the quality of the simulation but it is the operator who does.
Due to low cost of raw materials and low wage, price of injection mold tools in China attract buyers from the western countries, more important than pricing, the quality of tooling from China can compete with the European/ American quality and durability standards. If you are purchasing tools and dies from China, this article would be worth for your reading. If you still have not purchased from China, you will do soon, because this is going to be a trend and last long.
The quality of Chinese tools and dies are differences, there are good and bad factories like anywhere in the world, how can you tell the difference? Which is good one and which is bad one? The best solution is to visit, one of my friends from Germany, used to visit 50 tool makers before he start his first tooling project in China, well, this could be an exhausted process, but it definitely worth it. Being able to identify the good and bad tooling shops can save you a lot of times and troubles in making molds.
Nowadays and in the future more and more tooling buying decisions is on the hand of non-technicians, and the trend is they will have less and less weight on the final decision in the company. A tooling buying decision must be done by a team, where the decision power is balanced between the finance/purchasing, the engineering/production and the marketing/sales. If the power to decide is just on one side of the equation, results can be dramatic.
Over the years it has been found that price is not the best policy. Buying from cheap suppliers get you problems at a later date, is the correct materials supplied, is tooling to drawing, are drawing supplied and once the tool is delivered/trialed and the components are not correct to drawing - how long will it take to send back to the toolmaker for correction, and at what extra cost.
It's important to know the tooling shops you ask quote for each project or at least if you do not know it, know the type of tooling in which they are specialized. Mold makers cannot get a high-precision mold for an electrical connector with more than 800 small thin and long inserts on any tool shop.
Each case is a single one. A guy just looking at numbers in a spreadsheet knows about numbers and figures, only the engineering department can guide him to decide and unfortunately more often and often the tooling engineer opinion is not consider or as a small weight on final decision.
Each company has a unique set of requirements for tooling and molding. The tooling and molded part cost is always a significant consideration for most companies. When dealing with budgetary issues that limit tooling costs, I for one will always present a simple spreadsheet which identifies various tool options (like cavitation) along with capacity (hourly, weekly.....) and part price. Once these numbers are expressed and understood by the decision makers, it becomes obvious which option is most advantageous to the program at hand.
There are many variables involved in the determination of cavitation, grade of tooling, and related part price. However, there is the assumption that the decision makers just have to pick from the breakdown proposed and the project is a done deal. That is not always the case since in many situations, we could be quoting against 4 or 5 other tooling and molding companies, all doing the same breakdown, and quality is sometimes assumed, so it still comes down to price (and wish I had a dollar for every lost opportunity with that scenario).
I won't say that precision tools cannot be made or found in China, nor other Asian locations, however, I would lean towards there being difficulty in getting the highest quality there. If the conversation is expanded to move past the actual machining and become inclusive of the analysis and engineering then the separation becomes wider. Adding high level processing to the mix and this becomes more evident. The understanding of Quality Assurance (not Quality Control) plays into this very much. All these drive cost higher as the quality of the tool is raised.
There is little excuse for good high performance and tolerance tools to cost excessively more when built by a quality tooling shop regardless of where this is done. That said getting equivalence around the world is not easy.
That most customers are ONLY concerned with the finished part as opposed to verifying the quality of the tooling and/or the ease of molding process. Most Sourcing/Purchasing people as well as the Product Designers/Engineers never get to lay eyes on the Tooling they purchase in order to draw any conclusions on quality or precision aspects of tool features-----especially if tools are located in other countries.
For those of us that have had overseas assignments specific to managing tool builds and production startups I can attest to the fact that if you are not on site it is highly probable that shortcuts WILL BE taken by the tool maker and molder to cut costs and time. When a High level of Precision is required in a tool-----for moving parts, such as Lifters and Slides, the tool designer (as well as the Toolmaker) must consider material selection and hardness along with thermal expansion allowances on critical fits. It is those details that can only be verified by the most experienced tooling personnel as a Bench inspection with the tool apart.
To address the question:
- Extremely high capital investment
- Several hundred if not 1000's of labor hours required--- highly skilled
- Every single piece/part of a mold is a one of a kind custom made part and a mold may require hundreds of parts.
The good mold making companies in China have the very best equipment money can buy--- same as the EU countries or US. The country of origin has nothing to do with the quality you receive. Everything is dependent upon the specific source company chosen and the degree of involvement by a competent technical staff on behalf of the company buying the mold.
I have lived and worked in China for many years and I have seen the Good, Bad and Ugly as it pertains to tool makers and molders. Most of the horror stories I have heard about Chinese Toolmakers resulted from customers that did NOT have any technical expertise with tooling and/or molding and therefore fell into the trap of the attractive low cost. I can assure you that there are tool makers and mold makers in China that are "Best In Class" examples who have the latest technology to support the most difficult design applications. As for overall cost, one must consider the program requirements and the overall manufacturing plan. To look at China as a Tooling Source to support Molding in US (or in any other country) is viable but ends up having very little cost advantages once all is said and done.
Our company has a full tool room to complement our plastic injection molding operation. It is very important to our customers that we have on site mold building capabilities. Their major concerns are tool down time for repairs or modifications and also expense since they know the outside tool shop will have higher costs which we would have to pass on.
Whether the injection moulding simulations software (not only Moldflow) are 90% or 95% or 99% accurate or not: we should remember that these tools (or many of these tools) have more than 20 years of development and during this time they became better end better. From the other side, as the older of us may-be remember, these tools born to contribute to develop and to realize new plastic parts and products in "concurrent" way, that is to take in account from the beginning (concept phase) the possible issues coming from the tooling phase and from the production.
Today, after many years, are we sure that, even if these tools are much better, they are used in the best way? I can not give a general answer: I can only share with you my personal experience. Twenty years ago I introduced the sistematic use of the CAE tools (not only process simulation) in a Tier 1 Supplier for car market. From more than 10 years I'm the Director of a company who makes support and calculations for customers in the different market fields, in many different countries.
The quality mold tool should be the one that attends the customer requirements. There are many kind of injection molds. If you need a short cycle it must have conditions to give you a short cycle. If you need good surface quality in your product, the tool must be done with good steel and must have a good polish or treatment. In fact your question is a little bit subjective.
The good quality of tool depends of your expectations, and you must specify it when you are buying a mold. When 2 tool shops in the same area quote on the same tool to the same standards the pricing is usually within a few dollars. The difference in quoted prices comes from one company quoting a class 104 tool and another quoting a class 102 tool for the same part.