Today is July 24, unknowingly to the end of July. The first two or three days because of the more busy, there is no time to update the site. Today, Dongguan Plastic mold factory editor for everyone to introduce the impact of plastic mold products, the accuracy of the factors.
1. Manufacturing tolerances for molded parts
So the precision of the forming size should be higher than the accuracy of the relative size of the product, in general, mold manufacturing error to take plastic parts size tolerance of one-third or one quarter.
2. Impact of molding shrinkage
Which includes the difference between the calculated shrinkage and the actual shrinkage of the design mold, and the fluctuation of the shrinkage value of the plastic parts due to the fluctuation of the process conditions and the change of the batch number of the plastic parts. Resulting in the size of the accidental error.
3. Wear of molded parts
Plastic in the cavity in the high-speed flow and erosion of the cavity wall, stripping, plastic parts and cavity, core friction. As the molding process wear, die size becomes larger and bigger, the core size becomes smaller and smaller. Assuming that the core circumference is uniformly worn, it is assumed that the center distance remains substantially constant.
4. Install the mating error
Forming process without action requirements of the molding parts, the general use of transition with the installation. Requirements of the action of parts, such as the core, requiring the gap with the installation, the product size of the error, dynamic mode and die, will produce a mold position error.
5. Horizontal overflow of the thickness of the overflow
The use of overflow compression molding plastic parts, the horizontal overflow edge thickness often due to changes in process conditions and other factors fluctuations, so that the product height dimension error increases. So that the height dimension of the compression molded plastic part is regarded as the size affected by the movable part of the mold.
In summary, the maximum error δ that the product may produce is a combination of the above-mentioned various errors
Δ = δz + δc + δs + δj + δf
Δz - manufacturing parts manufacturing error
Δc - the total amount of wear used in the cavity
Δs - plastic shrinkage caused by fluctuations in plastic parts size changes
Δj - changes in plastic parts due to changes in the gap
Δf - the height of the plastic parts caused by the fluctuation of the thickness of the press.
The error value δ after the accumulation of various errors should be less than or equal to the dimension difference Δ of the plastic part, that is, δ≤Δ
Note: The above information from the Jiezheng mold finishing on the Internet, welcome reproduced, indicate the source!