ABS tube is ABS resin as raw material through the extruder plasticized melting, forming mold through the molding of a plastic pipe.
1, ABS tube characteristics and applications
ABS resin has been introduced in Chapter 1, it is acrylonitrile, butadiene, styrene copolymer. The use of ABS resin molding of the pipe has three kinds of monomer synergies and characteristics. ABS pipe tough, hard, good rigidity, dimensional stability, non-toxic, resistant to chemical corrosion, wear, heat, cold and good electrical performance, and the surface is easy to chrome; but ABS tube insolin, aldehyde and chlorinated hydrocarbons The
As the ABS pipe has better performance, it is widely used in some areas can replace metal pipe applications; ABS pipe can also be used as hot air duct and the ship industry, water supply and drainage pipes and used to transport a certain temperature and pressure Chemical corrosive liquid, can be -20 ~ +70 ℃ temperature range. But note that this kind of pipe should not be used in outdoor.
2, ABS tube extrusion molding production process line
ABS resin drying → extruder plastic raw materials to make it molten → mold forming tube → cooling stereotypes → traction → cutting → inspection → check into the storage
3, equipment selection
ABS pipe extrusion is mainly used single screw extruder, the screw structure should generally use the same thread distance, the thread depth for the gradient type, can also choose mutant screw structure, aspect ratio is relatively small, generally in (12 ~ 18) : 1 range selected, the compression ratio is (3 ~ 4): 1. Mold for forming pipe is a straight-through general-purpose structure.
4, ABS pipe extrusion molding process technical conditions
① raw material selection. ABS resin types are more, should choose suitable for extrusion molding tube resin, such as the choice of Lanzhou Petrochemical Industry Synthetic Rubber Factory production of E-7, E-3 or E-1 ABS resin.
② before the production of raw materials should be 70 ~ 80 ℃ in the oven for drying and drying treatment 4h. Control the water content below 0.1%.
③ plastic raw materials were molten state, extruder barrel temperature for the feeding section 150 ~ 165 ℃, plastic section 165 ~ 180 ℃, homogenization section 170 ~ 180 ℃.
④ forming tube blank molding mold temperature of 175 ~ 190 ℃.
⑤ draft ratio of 1 to 1.2.
⑥ cooling stereotypes with circulating water temperature of 15 ~ 22 ℃.
5, ABS tube extrusion molding precautions
① extruded ABS resin with the process temperature control should be used as low as possible, pay attention to the melt in the barrel stay time should not be too long, to avoid melt decomposition. The melt decomposition temperature was 250 ° C.
② production of ABS pipe, we should always pay attention to observe the melt color to the melt was light yellow for the plasticizing temperature control is reasonable. When the melt is light gray, indicating the barrel temperature deviation
High, to immediately reduce the barrel temperature.
③ sizing distance from the die should be controlled in the range of 15 ~ 35mm.
④ If the barrel process temperature control is reasonable, but there are still melt decomposition phenomenon (melt color light green gray), should consider the use of screw length and diameter ratio and then smaller.
⑤ screw speed should not be too high, generally not more than 20r / min.
6, ABS tube quality
ABS pipe quality requirements should be consistent with HG 21561-94 standard. ABS pipe size specifications see Table 1. ABS pipe working pressure and temperature of the provisions in Table 2. ABS pipe physical and mechanical properties in Table 3.
Table 1 ABS pipe nominal diameter and wall thickness dimensions
Nominal diameter dn / mm OD and tolerance D / mm PN = 0.6MPa PN = 1.0MPa
Wall thickness and tolerance δ / mm Approximate mass / (kg / m) Wall thickness and tolerance δ / mm Approximate mass / (kg / m)
15 20 ± 0.2 2.0 ± 0.4 0.12
20 25 ± 0.2 2.0 ± 0.4 0.15
25 32 ± 0.2 2.4 ± 0.5 0.23
32 40 ± 0.2 2.0 ± 0.4 0.25 3.0 ± 0.5 0.37
40 50 ± 0.2 2.4 ± 0.5 0.38 3.7 ± 0.6 0.57
50 63 ± 0.2 3.0 ± 0.5 0.59 4.7 ± 0.7 0.90
65 75 ± 0.3 3.6 ± 0.6 0.85 5.5 ± 0.8 1.26
80 90 ± 0.3 4.3 ± 0.7 1.22 6.6 ± 0.8 1.82
100 110 ± 0.3 5.3 ± 0.8 1.83 8.1 ± 1.1 2.72
125 140 ± 0.3 6.7 ± 0.9 2.95 10.3 ± 1.3 4.41
150 160 ± 0.3 7.7 ± 1.0 3.87 11.8 ± 1.4 5.77
200 225 ± 0.3 10.8 ± 1.3 7.83 16.6 ± 1.9 11.41
Table 2 ABS pipe and pipe fittings working pressure and the relationship between temperature
Nominal pressure PN / MPa Operating temperature / ℃
10 20 30 40 50 60 70
Working pressure / MPa
0.6 0.6 0.6 0.6 0.54 0.49 0.44 0.35
1 1 1 1 0.91 0.81 0.74 0.66
Table 3 ABS pipe material physical and mechanical properties
Item Index Test Method Item Index Test Method
Average density / (g / cm3) 1.03 ~ 1.07 GB 1033 Rockwell hardness 98 ~ 108 GB 9342
Tensile strength / MPa 35 ~ 45 GB 1040 Heat distortion temperature / ℃ ≥86 GB 1634
Bending strength / MPa 52 ~ 69 GB 9341 Vicat softening temperature / ° C ≥94 GB 1633
Impact strength (notch 23 ° C) / (kJ / m2) 9 ~ 30 GB 1843