Plastic PP Chair Household Mould Feature
Mould Steel: P20
Cavity Treatment: Nitriding on the surface
Runner: Hot runner with big gate
Delivery Time: 45 days
Chair Warping From Injection Machine?
Why the chair warping? how could we solve this problem?
PP chair warping after removal from Chair Mould are very common and are always the result of frozen-in stress; differential shrinkage or，with filled materials，filler orientation.
This is nearly always a processing problem，but it can also be caused by a machine failure or incorrect component design.
Anything that prevents injection at the correct rate will contribute to warping.
Thus，the non-return valve on the screw not seating and allowing backflow along the screw flights prevents proper injection and causes warping.
In fact, PP Chair Mould which would have warped，except that it was restrained by a strong rim, such as the base of a bucket or bowl，will have a tendency to break down in service.
Expedients such as differential mould cooling and jig cooling are only partial palliatives.
The only real cure (given correct component design) is correct injection and mould filling.
Both the two expedients mentioned will certainly produce unwarped mouldings, but the question is: how long will they retain their shape?
For example,，a component for use at elevated temperatures may be free from warping when the first made，but after a few weeks or months of use at its normal working temperature it may warp sufficiently to become unusable.
When warping occurs, the injection rate should first be checked. Short mouldings should then be made by the method described in the section on Short Mouldings，to determine how the mould is filling.
Check Our Chair Mould Video Below
Moreover, then，having ascertained that filling is uniform and that material is reaching all extremities of the moulds at the same instant，mouldings should be made at the same (correct) injection rate with exactly the correct amount of feed.
In nearly all instances, this method will prove satisfactory. If the material does not flow uniformly in the mould, it will be necessary to ease some of the channels or， with a deep-drawn symmetrical article，to true up the mould parts to make sure that all the flow paths are of equal thickness.
If warping is still a problem，even with this moulding technique，the PP Chair Mould may need to be altered so that several pin-point gates can be used to cause virtually undirectional flow during filling.
On account of the cost of modifying a mould, this should be thought of only as a last resort if all else fails.
Hongmei Company Service
Our company will offer you professional and promptly communication according to your project.
First, we will make PP Chair mould drawing according to your samples /product drawing with your request or modification,and then send to you for approval. Also we will provide you technological suggestions according to our experience and knowledge.
When manufacturing the moulds,we will send you processing report with pictures every 7-10 days by email.
We will send you PP Chair Mould testing vedio by email and the samples by DHL/TNT.
If our product have quality problem during our guarantee period, we will send you free for replace the broken piece; also if you have any issue in using PP Chair mould, we provide you professional communication.
Hongmei Mould Packing and Delivery
Our Mould Advantage
1.Reasonable part design and qualified mold design are the basic factors.
2.Precise and strict process supervision.
3.High quality Chair Mould steel and standard spare parts.
4.Efficient communication between supplier and customer.
5.Interchangeable inserts block for different chair backrest versions. Backrest inserts can be easily changed on the machine.