Preparation process of ABS sheet

Preparation process of ABS sheet
(1) The raw material is dried. ABS pellets are extremely hygroscopic and must be used before use.
Dry. Drying can use hot air circulation oven or hot air hopper type reclaimed material
Dryer. The drying process undergoes three stages of preheating, constant temperature drying and temperature drying. The drying process parameters usually used are: the drying temperature of the new pellet is (85 +/- 5) ° C, and the recycled material is (90 +/- 5) ° C; the drying time is not less than 3.5 h, but it is not suitable. Too long.
The factors affecting the drying effect are as follows:
1 The nature of the raw materials, including the raw material composition and the shape of the particles. Generally, the stronger the hygroscopicity of the raw materials, the slower the drying speed; the addition of additives increases the hygroscopicity; the larger the raw material particles, the longer the diffusion process and the slower the drying speed.
2 The lower the humidity of the drying medium (air), the higher the moisture absorption capacity, the faster the drying speed, and the easier it is to dry.
3 The higher the drying temperature, the greater the energy of the water molecules, and the higher the diffusion rate, the faster the drying speed. For this reason, the drying temperature should be high and should not be low, so as not to cause discoloration, agglomeration and decomposition of the pellets.
4 The faster the flow rate of the drying medium, the stronger the heat transfer between the medium and the material, and the faster the drying speed.
(2) Extrusion molding
The key to extrusion molding ABS sheet is the plasticizing effect, and the main factors affecting the plasticizing effect are set temperature, screw speed and screw design parameters. In addition, the factors affecting the feeding effect and exhaust effect cannot be ignored.
(3) Cooling and shaping
During the cooling and setting process, constant temperature water is used to control the temperature of the three rolls, and the temperature of the constant temperature water can be controlled by cooling water and heating. The cooling setting process parameters are: three rolls and traction line speed: 0.9m/min~4.1m/min; upper roll temperature in three rolls: 80°C~118°C, medium roll temperature: 95°C~120°C, lower roll temperature : 75 ° C -90 ° C; the temperature of the cooling water of the three-roll constant temperature system is not higher than 35 ° C.
It is worth noting that if the temperature of the three rolls is too high, the sheet will be too soft and leave the roll to form fine horizontal stripes; if the temperature is too low, the sheet will be separated, causing hem or roll marks; if the temperature of the three rolls is improperly matched It also causes the sheet to bend. The roller spacing will affect the thickness of the sheet, and the spacing between the middle and upper rolls will be improperly adjusted, which will result in pinholes or hem. When the three-roll line speeds are inconsistent, the sheet will be wavy.
If the traction is too tight, the sheet shrinkage will be high.

  • 12/04/2019
  • Recently
Click here to view Previous or Next

Related News

Cost-effective industrial laminate

Cost-effective industrial laminate

  • 13/02/2019 09:10:01

The cheapest industrial laminates (Class X) are used in large quantities where the dielectric properties are less important. It is made from unbleached kraft paper and about 30% phenolic resin. It has …

Read more

Casting PA film and production technology

Casting PA film and production technology

  • 21/12/2017 09:33:12

Casting PA film and production technology 1. Casting PA film and its raw materials used: PA film has the advantages of high strength, good toughness, good transparency, good heat resistance and cold…

Read more

Cast film mechanical winding device

Cast film mechanical winding device

  • 19/12/2017 09:21:48

Cast film mechanical winding device Corona treatment device: cast film after corona treatment, can improve the surface tension of the film to improve the printing of the film and together with other…

Read more

Downstream production line auxiliaries

Downstream production line auxiliaries

  • 18/12/2017 09:42:18

Downstream production line auxiliaries Thickness measurement device: In the high-speed continuous production process, cast film thickness measurement must be non-contact automatic tracking. Most o…

Read more

Hot News

ABS sheet extrusion molding process control points

ABS sheet extrusion molding process control points

ABS sheet extrusion molding process control points(1) Feeding. The material should be fed in time to ensure that the hopper is not empty, in order to prevent the air from directly entering the drying cycle system, affecting the dry return air speed. Diffe

Preparation process of ABS sheet

Preparation process of ABS sheet

Preparation process of ABS sheet(1) The raw material is dried. ABS pellets are extremely hygroscopic and must be used before use.Dry. Drying can use hot air circulation oven or hot air hopper type reclaimed materialDryer. The drying process undergoes thre

Add waste materials to ABS sheet

Add waste materials to ABS sheet

Add waste materials to ABS sheet1. Material selection and performanceABS is an amorphous polymer. Under the action of heat and external force, it enters the viscous flow state from the glass state at room temperature through a high elastic state to form a

Plate (sheet) material forming process

Plate (sheet) material forming process

Plate (sheet) material forming processThe plastics of the production board (sheet) are mainly soft polyvinyl chloride, hard polyvinyl chloride, polyethylene.Alkene, polyamide, polymethyl, polycarbonate, cellulose acetate, etc., the first four varieties ar

Characteristics and uses of PTFE - Suspension PTFE

Characteristics and uses of PTFE - Suspension PTFE

Characteristics and uses of PTFEVariety: Suspension PTFEfeature:1. White waxy fine particle material;2. Poor strength;3. Self-lubricating, non-adhesive, stress cracking is good, dynamic and static coefficient is the lowest among plastics;4. Excellent resi

Tags