As a purchasing engineer, your focus is to use professional knowledge to communicate product positioning to suppliers so that their products meet all your requirements and remain within budget.
But before choosing the partner of injection moulding, it is better to know the injection moulding process first.
The following description lists two key points in the injection process; you will learn more about them before working with the injection company。
Injection Molding Process Steps
I: Making injection moulds。
Injection moulding process is carried out through the mold。 Before the injection moulding process is started, the mold must be manufactured。 Of course (first of all, there must be three-dimensional design drawings of the product) which contains the shape of the parts you want。 Injection moulds are most commonly made of steel (although some parts may require other materials) and produce parts with very small tolerances of +/-。0005 inches (accurately speaking, human hair is about +/-0。0003 inches)。
If large quantities of plastic parts are to be manufactured (with a total production of more than one million pieces), multiple cavities may be required inside the die, so many plastic parts will be produced in each cycle. At HKY Mould, we have the ability to create moulds with multiple cavities - we can produce tens of thousands of parts per day.
Step 2: Manufacture plastic products.
Put the finished mould into the Injection Moulding Machine.
Heat the plastic granules until they are liquid.
If necessary, the plastics are heated by hopper (because the moisture in the plastics may cause damage or hydrolysis of the finished products)。
Plastics are vacuum transported to the injection moulding machine through a high-pressure fan.
The plastic is connected to the sucker through a heated injection barrel。
Plastic is injected into the die through a sucker under pressure。
Plastics enter the mould cavity - cooling the plastic material to solid state to form plastic parts.
Mould opening, cooling plastic parts are taken out of the mould by hand (in vertical injection moulding machine) or by gravity (in horizontal injection moulding machine).
Choosing Injection Molding Partners: Six Things to Consider
If you are ready to make your product a reality, you must find partners that are suitable for your injection molding needs. Next, we list some considerations for you to choose the right partners.
1. Professional knowledge
When looking for Injection Molding suppliers, we can reduce the project risk value by matching companies with related products or similar experience; companies with relevant product experience may have more experience and the required knowledge and technology。 You can narrow your search to a specific base, such as high volume molding, Over-molding or 。 Also, be sure to ask the exact technology for the specific project you may need。 If they don't have the above technology, but know if they are willing to get it。
Either domestic or overseas companies are chosen to cooperate in injection moulding。 Please consider the following questions:
Mould is produced at home or abroad, is it new product development? The use of products, is it smooth surface, or grain surface, or mass production of moulds? As well as the use of resin, the final determination of annual consumption, service life, clear requirements and mold grade standards, provided to suppliers, will get more accurate mold prices and injection parts unit price。
Here are some standards for the life grade of Plastic moulds.
101 grade plastic moulds, requirements to meet the service life of more than 1 million times
The service life of 102 grades of moulds is required to reach 500,000 to 1,000,000 times.
Class 103 requires a service life of 300,000 times.
Class 104 requires a service life of 100,000 times.
The lowest level 105 is actually what we often call experimental rapid tooling, which requires a life of 5000。
Ideally, the company you choose to work with in the Injection Molding process should be able to manufacture the mould for you, and have the necessary expertise to ensure that your existing mould can meet the quality standards you need。 Some companies - in the United States and China - outsource moulds, which means you have less quality control。
3. Production capacity
Before choosing partners for injection moulding process, consider the output that the company can handle。 If you need to produce 10 million pieces a year, and the moulder produced only 1 million pieces for all its customers last year, you should look elsewhere。 If there is no such capability, it will eventually lead to prolonged delivery time and quality problems。 Or, if you only need to produce 5,000 pieces a year, you may not want to choose a moulder that handles millions of unit orders。
You will work with your molder for a long time, so it is important that suppliers are honest and trustworthy。 The following tests can be performed:
I. Observe the rate at which the molder reacts to the small problems you find. Find out if they have a process for dealing with problems during the injection molding process.
II. Check the time it takes for the molder to return your call or send you an update. If the company is slow to respond at the beginning of your relationship, imagine what the future will look like!
Pricing of plastic injection moulding process can be considered in addition to operator's cost, material cost, cutting tool and processing cost, rental company site, injection moulding machine use time, and injection moulding machine cycle time, the number of holes in plastic parts. If a company has a solid injection moulding process, it will have strict standards to ensure that each part is removed from the mould at the right time to avoid defects and appearance problems.
HKYMould is an Injection Molding custom-made Chinese factory with 15 years of experience in opening a factory, creating an elite team of English-savvy professionals, providing precision plastic mold manufacturing and one-stop service for injection molding, die-casting mold manufacturing and molding. Reduced the hassle of supply chain management for customers.
Adress: Room #102, Building #50, Shu Tianpu Xin xing Industry Zone B, Matian Street, Guang Ming District, Shen Zhen city, Guang Dong Province, China, 518101。