Company News

The drawing of the mold and the inking of the gate

2025-08-05

The drawing of the mold and the inking of the gate

Mold drawing

Phenomenon: The two products are textured products and there is a phenomenon of mold pulling.

Analysis: Slow speed will cause the product to cool down too quickly. The position switching is too slow.

Characteristics of injection molding machines

Grade: DEMAG(Ningbo), clamping force: 120t, plasticizing capacity: 130g.

(2) Mold characteristics

Mold ejection number: 1×2, glue injection method: point gate, ejection method: push plate ejection, mold temperature: 90°C (constant temperature machine).

(3) Product physical evidence

Material: PC+ABC HP5004-100, Color: black, Product weight (single piece) : 3.2g, nozzle weight: 13g.

(4) Analysis of causes of defects

1.The main channel of the mold is long and thin. The glue inlet method is submersible glue inlet. The molten material flows near the glue inlet. Due to the slow speed, the local pressure of the product is too large, resulting in the mold pulling phenomenon.

2. The inherent limitations of the equipment itself have led to the inability to improve the situation through machine adjustment.

(5) Countermeasures

The products debugged after replacing the DEMAG 100T machine are qualified, and the injection speed of the machine can reach 220mm/s.

Injection molding process table

Injection molding machine: Haitian 1201T, Type B screw, injection volume 131g			Product Name: M169 Battery Frame
Raw materials: ABS+PC HP5004	Colour: Black	Drying temperature: 100°C	Drying method: Dehumidifying dryer	Drying time: 4 hours	Recycled material usage: 0
Finished product weight: 3.2g×2=6.4g		Nozzle weight: 13g	Mold output: 1×2	Gate injection method: Point gate

Barrel temperature					Mold temperature	Use machines	"Settings	"Actual
1	2	3	4	5	before	Water temperature machine	110°C	102°C
320°C	315°C	315°C	300°C	/	before	Water temperature machine	110°C	102°C
△	△	△	△	△	after	Water temperature machine	110°C	101°C
△	△	△	△	△	after	Water temperature machine	110°C	101°C

	/	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

Intermediate time	Injection time	Cooling time	The entire duration	Back pressure	Rotational speed	Retraction speed	Material quantity position	Retraction position
1	5	10	25	5	10 15 10	10	38	3

Mold closing protection time	Supervise the feeding time	Clamping force	Ejection length	Ejection times	Rotation position	Blowing delay	Blowing time
1	10	60	45	1	15 35 38	/	/

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

Mold ink flushing

Phenomenon: Ink surges at the gate of the S10 face frame.

Reason: During IML injection molding, the gate of the sheet material often appears transparent.

Analysis: High speed will cause material melting, intensify shearing and generate high temperatures. The ink has poor heat resistance.

Characteristics of injection molding machines

Grade: DEMAG (Ningbo), clamping force: 50T, plasticizing capacity: 42g.

(2) Mold characteristics

Mold ejection number: 1×2, glue injection method: point gate, ejection method: push plate ejection, mold temperature: 70°C (constant temperature machine).

(3) Product characteristics

Material: ABS PA758, Color: Transparent, Product weight (single piece) : 1.5g, sprue weight: 13g.

(4) Analysis of causes of defects

1.The main channel of the mold is quite large, and the glue inlet method is submersible glue inlet. When the molten material flows near the glue inlet, due to the excessive speed, it causes high shear, resulting in a rapid and instant temperature rise of the molten material.

2. The ink is not resistant to high temperatures, resulting in ink flushing.

(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. Then, in the second section, fill the area near the glue inlet at a slow speed and a very small position. In the third section, quickly fill 90% of the mold cavity to prevent the high-temperature molten rubber from cooling. In the fourth section, slowly fill the mold cavity. Finally, switch to the pressure-holding switching position.

Injection molding process table

Injection molding machine: DEMAG50T, Type B screw, injection capacity 42g			Product Name: Transparent Mirror
Raw material: ABS PA758	Color: Transparent	Drying temperature: 70°C	Drying method: Dehumidifying dryer	Drying time: 2 hours	Recycled material usage: 0
Finished product weight: 1.5g×8=12g		Nozzle weight: 13g	Mold output: 1×8	Gate injection method: Point gate

Barrel temperature					Mold temperature	Use machines	"Settings	"Actual
1	2	3	4	5	before	Water temperature machine	70°C	72°C
260°C	255°C	250°C	210°C	/	before	Water temperature machine	70°C	72°C
△	△	△	△	△	after	Water temperature machine	70°C	71°C
△	△	△	△	△	after	Water temperature machine	70°C	71°C

	/	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

Intermediate time	Injection time	Cooling time	The entire duration	Back pressure	Rotational speed	Retraction speed	Material quantity position	Retraction position
1	5	10	25	5	10 15 10	10	38	3

Mold closing protection time	Supervise the feeding time	Clamping force	Ejection length	Ejection times	Rotation position	Blowing delay	Blowing time
1	10	60	45	1	15 35 38	/	/