Trial Mold Verification

In order to avoid unnecessary time-wasting and troubles during mass production, it is indeed necessary to pay patience to adjust and control various processing conditions, find the best temperature and pressure conditions, and formulate standard test procedures, which can be used in establish daily working methods.

Mold trial process: (CHT mold trial verification standard)

1. Understand the relevant information of the mold:

It is best to obtain the design drawing and product drawing of the mold, and analyze it in detail by the mold technician and the tryout technician:

  • Mold precautions (hot runner, valve, cylinder, ejector, slider, cooling, etc.)
  • Product precautions (materials, deformation, sticking, ejection, metering, pressure, size, shrinkage, shape, etc.)

2. When it is determined that each part of the mold moves properly:

  • The injection measurement settings are very important. (Principle: the lowest first segment is convenient for ejection measurement)
  • Check the size and weight (compare with the design value)
  • Evaluation of molding conditions; adjustment test of condition parameters above +/-10% (principle: medium speed and medium pressure, except for special)
  • Mass production evaluation: (cycle, manipulator, temperature, valve, cooling, appearance, etc.)

3. Test model verification report:

  • Mold improvement items: (runner, movement, exhaust, mold sticking, cooling, deformation, etc.)
  • Product improvement items: (welding line, lack of glue, shrinkage, burrs, step difference, size, etc.)



Mold Assembly

Before assembling, carefully study and analyze the assembly drawing and part drawing, understand the function, characteristics, and technical requirements of each part, determine the assembly benchmark and finally achieve the product quality indicators, mold action accuracy, and various aspects in the use process. Item technical requirements assembly benchmark (strictly in accordance with the requirements of the drawings):

  • The main working parts in the plastic mold such as core, cavity and insert are used as the reference parts for assembly, and other parts of the mold have assembly reference parts for preparation and assembly.
  • Take the guide post and guide sleeve or the base surface of the mold template side as the assembly reference surface for trimming and assembly.

Mold assembly accuracy (the inspection tolerance of all parts of CHT mold before the next processing procedure: circulation within +/-0.015, while the following points need to be observed):

  • The mutual accuracy of various parts, such as distance dimensional accuracy, coaxial, equality, perpendicularity, etc.
  • Relative motion accuracies, such as transmission accuracy, linear motion, and rotary motion accuracy.
  • Fitting precision and contact precision, such as fitting clearance, interference contact condition, etc.
  • The wall thickness of the plastic molded part. When the mold is newly made, the wall thickness of the molded part should be biased to the lower limit of the size.

Confirmation after mold assembly (confirm strictly according to the list before CHT trial production):

  • Glue feeding system (hot runner, needle valve, pump, main flow channel, branch runner, glue port, etc.)
  • Actuating parts (inclined roof, block, slider, cylinder, valve, etc.)
  • Ejection system (thimble, top block, inclined top, top plate, mechanical rotation, etc.)
  • Cooling system (water cooling, air cooling, flow rate, oil cooling, electric heating, temperature, etc.)
  • Protect safety devices (hot runners, guide posts, positioning, guides, lifting rings, clamping buttons, operation signs, etc.)



Mold Manufacturing

Our Mold Making Facility:

Mold Making: we have domestic, offshore, and in-house mold making facilities.

Once the prototype is finished, the mold can be designed and quoted. From there, our expertise in mold making will become invaluable. At CHT Mold, there are dozens of skilled experts with more than 20 years of mold manufacturing experience.

As a mold manufacturing process: prototype part design, quotation, DFM, MF, mold design, mold making, trial mold, inspection, mold improvement.

We have all of the equipment necessary to manufacture prototype and production molds in-house.

We have the ability to make molds in our company. Although there are other individual outsourcing, if the company chooses individual outsourcing, customers can know that the mold is handled by CHT professional department from beginning to end. An important part is that CHT takes full responsibility for the entire process. There is no blame between the mold maker and the third party. We are responsible for the entire process, and we eliminate the option to shirk responsibility to others. This means that you will get direct answers and resolved issues without having to act as an arbitrator between two independent companies.

We also provide low-cost overseas molds.

Additionally, we can offer lower-cost overseas molds if that suits the customer’s needs best. We still stand fully behind the quality of the mold and the finished product.

And we offer Mold Maintenance.

Molds (or tools) don’t run flawlessly on their own. One of the most important advantages of CHT is our ability to perform maintenance on molds in our shop. Our company uses on-site tools to maintain and repair molds as needed. This contributes heavily to our ability to keep production at the expected rate. We perform frequent checks on molds before and after use to ensure they are ready to operate impeccably.

Many companies don’t have the capability to provide such a comprehensive start to finish mold making experience.





For Changhong Technology and the design, development, and production of high-precision molds and plastics parts, a standard DFM report happens when we first review a part that we deem more complex than normal, or that might benefit from adjustments in design from the work of a Design team to the R&D team table, where thoughts and ideas turn into physical reality.

A Changhong Technology DFM report usually takes around 72 hours to produce and comprises 2 parts:

1. Requirements Gathering

Part Detail Part Type Part Detail Accessory Detail
Part Number / Part Name:
Raw Material of the Part:
Shrinkage of the plastic material:
The color of the port:
The finishing of the part:
The thickest wall:
The thinnest wall:
Part dimention:
Cosmetic: Yes / NO
Functional: Yes / NO
Cavity Steel / Core Steel:
Mold base steel:
A/B plate steel:
The clamping force of the injection machine (Machine Tonnage):
Injection Gate:
Molding Cycle:
Runner Weight:
Part Weight:
Mold Size:
Mold Base: Standard ( Such as LKM ) / Customize
Sprue / Nozzle: CHT Standard / Custom-ize
Hydraulic Cylinders: Yes / No
Hot Runner: Yes / No
Guide Bush: Standard / Custom
Others: Standard / Customize

2. Mold & Part Analysis

Thickness Analysis — determine the thickness Of the wall according to the fluidity Of the material to avoid shrinkage or unfilled;

Draft Analysis - determine a part line, add some draft to make demolding easily;

3D Structure Analysis - To see if there is an undercut that would be removed; To simplify the structure if it is necessary. To determine the mold structure according to the 3D structure of the mold. In one word, to make the part demolding successfully and be available for mass production; Including:

  • If a lift is needed. If yes, please display the 3D dynamic effect;
  • If the slide is needed. If it is, show the direction of the slide;
  • If there is any other accessories need;

Mold Flow Analysis - to determine the injection gate, including gate type, gate number, and gate location; To determine cool system - the layout and the diameter of cool water runner;

The Layout of the Mold - shows the layout of the mold, the 2D drawing of the mold.



Mold Flow Analysis

CHT Talent

Our mold-flow engineers have worked on thousands of projects to gain the wealth of experience they now possess. Experts at using simulation software we can enhance part and mold design at the right stage of development - the beginning - reducing time and cost across the board.


By involving our engineers at the early stages of your project, you can be sure of our experience as part of your arsenal to getting a product to market in the shortest possible time, at the highest quality.

By advising on mold design, we have saved our clients countless hours and dollars in development time and take pride in the overall standard of mold tools we produce year after year.


How is a injection mold made?

We are frequently asked how we manufacture injection mold, and more specifically how do we do it. To answer this, it helps to put our services into context. The cost and time required to produce traditional high-volume production injection mold tooling are a consequence of needing to maximize productivity and minimize per part costs for large production volumes. Very high volumes and high production rates dictate hardened steel tooling with full automation, multiple cavities, and advanced runner and cooling systems. Such tools are complex, time-consuming to produce and test, and even more difficult to modify once in operation. However, when the customer requires a few hundred injections molded components on a tight delivery schedule, and the rate of production is not required to be high, a completely different mold production approach can be employed.

Understanding customer requirements are the foundation for every successful injection mold project

From the very outset of every client engagement, we strive to understand the full context of the project we are producing molded components for, to be sure we are addressing the customer’s primary needs, and are making the best decisions for the mold design. For example:

  • What is the end-use of the product?
  • What do the components we are molding do?
  • Will components be used for form, fit, function testing?
  • Is the project only a model for a coming trade show?
  • Are the components intended as end-use production parts?
  • How was the requested material chosen and what were the requirements?
  • Do the components need to have a high-quality surface finish or special texture?
  • Will the customer need 25 components in a few days or 250,000 over the next few months?

Understanding and acting on the answers to each of these questions are the foundation of a successful injection molding project.

Translating requirements into fast action

Once we have gathered the requisite contextual information, our engineering and design team initiate an extremely tightly managed process of converting requirements and 3D CAD data into a mold proposal. Even at this early stage, the project is already being managed by our proprietary design to assure efficient execution at every stage downstream. This is essential, in that it assures that everything quoted can be designed, machined, and molded efficiently to meet our very short delivery timelines. Mold design engineers take into consideration the specific characteristics of the molded polymer, the required production volume and rate, and the per-part cost objectives of the customer.

Form follows function when designing an injection mold

Even within the sub-category of prototype and low volume injection molding, there are many choices to be made on specifically how each mold is to function. In the case of very simple low volume components in a forgiving material, the mold would be a simple single cavity open and close design. When undercuts are required the designer will consider current and future production volumes to decide if the tool will be automated or include hand-loaded inserts for these features. The use of hand-loaded inserts reduces the cost and production time of the mold but generally increases the per-part cost due to the manual tending of the molding machine. Finally, in the case of complex geometries, including inserts and over-molded features in multiple materials, the full spectrum of design concepts will be deployed to balance product needs with cost and delivery time constraints.


Design validation in electrons, not metal

Following initial mold design, our team performs mold flow analysis to reduce the likelihood of problems in the molding process. Depending on the complexity of the molded component, this can be a simple filling simulation all the way to complex warpage and shrinkage analysis, fiber orientation estimates for filled polymers, and other factors. Catching issues and collaborating closely with our clients at this stage to resolve potential problems leads to better products and higher on-time-delivery rates. Although we are quite nimble in rectifying problems that arise in the molding process, it is far easier and more efficient to do this when the mold is still in CAD and not in the press. Ultimately the completed mold design is reviewed with the client for approval prior to production.

Preparing for production

Once the mold design is complete, the process starts to really accelerate. The individual components of the mold (core, cavity, inserts, actions, ejector pins, etc.) are designated for their respective manufacturing process: CNC machining, EDM (electrical discharge machining), grinding, and manual machining.

The expert finishing touches complete the injection mold build process

Production of high-quality injection molds will always demand the personal attention of expert mold makers. At CHT we have a team of highly talented and hugely experienced mold makers who finish and test every mold to assure proper functioning of the mold and to achieve the desired surface finish of the molded components. This is part engineering and part artistry and cannot be rushed. So, all of the efficiency we build into the prior mold production steps assures that this team has enough time to do the mold finishing process properly. Naturally we do everything possible to maximize the mold surface finish quality coming out of CNC and EDM so that manual finishing or laser texturing is less difficult. Finally, the various components of the mold are all brought together in the assembly department where the functional mold is built up and tested prior to delivery to the molding department.