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The mold case integrates lines and exposed white

• 2025-08-04

The mold case integrates lines and exposed white

Mold fusion line：

Phenomenon: There are fusion lines on the razor's outer shell and blade holder.

The reason is that due to the product structure, the glue position at this location is too thin, resulting in a melt flow point and a fusion mark.

Analysis: The position setting of the molten adhesive is not precise enough. The setting of the injection speed is not precise enough. The temperature at which the glue is melted and dissolved is insufficient.

(1)Characteristics of injection molding machines

Grade: Demag (Jiangsu), clamping force: 100t, Plasticizing capacity: 94g

(2) Mold characteristics

Mold ejection number :1x2, glue feeding method: small water outlet to large water outlet, ejection method: Ejection by ejector pin. Mold temperature :90℃(constant temperature machine)

(3) Product characteristics

Material: ABS PA757 37826, Color: grey, Product weight (single piece) : 5.39g, Spout weight: 4.32g

(4) Analysis of causes of defects

1.The flowability of the raw materials used in the product is slightly worse than that of other raw materials.

2. During the product's molding process, the precision requirements for various process parameters such as position, speed, and calibration are relatively high, and they need to be set very preciselyAccurate.

3. The temperature setting is unreasonable.

(5) Countermeasures

1. Utilize multi-level injection and position switching.

2. In the first section, fill the flow channel to the glue inlet at a relatively fast speed and find the corresponding switching position, and then use the second section Just fill it slowly and in a very small position near the glue inlet. The third section fills 70% of the mold cavity at medium speed to allow the glue flow to pass through the product Where the meat is thin, avoid the molten rubber compound from converging there. In the fourth section, fill the mold cavity slowly to completely expel the air inside the cavity Avoid adverse phenomena such as trapped gas and burning. Finally, switch to the pressure-holding switching position.

Auto Mould_Taizhou Jiefeng Mould Co.,Ltd. (jfmoulds.com)

Injection molding process table

The mold shows white： 

Phenomenon: The decorative parts on the bottom shell of S28 show white.

Reason: This is an IML product. After the material is silk-screened and then placed in the mold for injection molding, due to the inconsistency between the unfolded area of the sheet and the area of the front mold core, poor edge wrapping occurs, resulting in a white exposure phenomenon.

Analysis: The projected area of the sheet material is inconsistent with that of the mold. When hot-pressing and punching sliced materials, there is a deviation.

(1)Characteristics of injection molding machines

Grade: DEAMG (Ningbo), Clamping force :50t, plasticizing capacity :42g

(2) Mold characteristics

Mold ejection number :1x2, glue injection method: point gate, ejection method: Ejection by ejector pin, mold temperature: 70℃(constant temperature machine)

(3) Product characteristics

Material: PMMAIRK304, Color: Transparent, Product weight (single piece) : 2.4g, nozzle weight: 8.2g

(4) Analysis of causes of defects

1.The projected area of the sheet material is inconsistent with that of the mold.

2. Deviation occurs when hot-pressing and punching sliced materials.

3. When placing the sheet material, the technique was not standard and it was placed off-center.

(5) Countermeasures

1.Increase the projected area of the sheet material.

2. Adjust the hot-pressing punching die.

3. Add positioning brackets for shaping.

Injection molding process table

	/	50	Holding pressure	Pressure-holding position		100	110	120	Injection pressure
	/	3	Holding pressure time	12		12			Injection pressure position
Residual amount of injection glue		/	10	/	55	3			Injection velocity
7.8		/	/	/	12	23.5			Velocity of fire position

Commodity Mould_Taizhou Jiefeng Mould Co.,Ltd. (jfmoulds.com)