Production process sequence of extrusion molding of UPVC pipe
DATE：2022/9/3 9:30:24 / READ： / SOURCE：This station
Production process sequence of extrusion molding of UPVC pipe
It can be divided into two parts: the raw material preparation and supply system and the extrusion PVC pipe production system. The raw material supply system is the raw material supply system for extrusion PVC pipe
Production process sequence of main raw materials (PVC resin and auxiliary raw materials):
(1) Resin and various auxiliary raw materials shall be measured according to the material formula for pipe forming → in the high-speed hot mixer
② The production system of extruded PVC pipe products shall be evenly mixed → the raw materials shall be cooled, stirred and cooled → the extruder shall be used for mixing and granulation → the materials shall be fed into the extruder from the storage bin (c) → the extruder shall extrude the raw materials into a molten state → the pipe blank shall be formed through the molding die → cooling and finalization → traction → cutting → quality inspection → weighing and warehousing
(2) Raw material selection: the main raw material for PVC pipe extrusion molding is suspension polyene SG4 or SG5 type resin, which is combined with a variety of auxiliary materials (additives) as follows (see also table 4-5 for examples). Formula I (mass fraction)
(2PbO) real estate service (p6st) of national Yelin glue
Extruder. Refer to table 3-7 for outgoing specifications; The structure is that when the mixed raw materials are extruded and granulated, the general-purpose single screw can be used
(3) Preparation
Pitch gradient type, length diameter ratio L / D - (20 ~ 25): 1, compression ratio 2.5 ~ 4. If the powder is extruded directly, a round twin-screw extruder should be selected. Single screw or twin screw
The structure of PVC pipe mold is shown in Fig. 5-3. The composition of the extrusion line for forming hard PVC pipes is shown in Fig. 51. Refer to Chapter 4 for forming hard (4) and workpiece. Extrusion process temperature of UPVC pipe. From the barrel feeding section to the homogenizing section, the temperature is 100 ~ 140 ℃, 150 ~ 170 ℃ and 160 ~ 180 ℃. The molding die temperature is 170 ~ 185 ℃. (5) The quality of general UPVC pipes shall meet the requirements of gb1302091. See table 5-38 for the heterodyne. The length of the pipe is generally 4m, or more than 6m according to the user's requirements.
Case 5: plastic pipe bridge out molding
Physicalization of UPVC pipes for industrial use (gbt42191996)
Use general-purpose single ground line
Indicator indicator name indicator
< 1.55 longitudinal retraction /% ≤ 5
≤ 1.50 flat acetone immersion, no delamination, no fragmentation, no crack, no fracture
No fracture, no leakage ≥ 80 tensile yield stress / MPa ≥ 45
(refer to the fourth meaning)
The homogenization sections are,
4210-196
185℃。
Average external light limit deviation / mm nominal pressure (temperature: 0 ~ 25 ℃) / MPA 221
Bim pa0.4 pa0.6 pn0.8 pn1.0 pn1.6
Piping array
S16.0 S10.5 S8.0 S6.3 S4.0
Wall thickness (E / mm)
Limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value discoloration line and other phenomena; The dimensional error of wall thickness shall conform to the provisions in table 5-4; End face stress of pipe
20.1 + 2.3 straighten the pipe axis.
(6) Key points of process operation
① When the metered raw materials are mixed with a high-speed mixer, they must be mixed according to the process requirements
+2.80
7.9 + 3.0 mass. Mix and stir according to the required feeding sequence to ensure the mixing of PVC resin and other auxiliary materials
@When forming white PVC pipes, the titanium dioxide (TiO2) in the formula should be put into use within 2min before the end of the high-speed mixing process to avoid reducing the whiteness of titanium dioxide.
① Note that the heating temperature of the high-speed mixer should not be higher than 45 ℃ when mixing materials; After cooling down, deyihua real estate will assemble bars and molds, and prepare to produce. After learning from Hong Kong, the Australian compound should be in a loose state, and the material temperature should be lower than 45 ℃ When the machine needs to stop production for a long time due to the removal of residual materials, Fang Hai should be asked to rectify and clean it immediately. When the operator is not allowed to operate ⑥ in the direction of the outlet, he should observe the extruded materials from the outlet to prevent them from being damaged by the decomposition of smoke materials.
Jane's heating temperature. Bright and elastic indicates that the plasticization of raw materials has reached the quality, otherwise the machine should be properly improved. If the single screw extruder uses powder to extrude and form pipes, it should be noted that the thread depth and length to weight ratio of the screw should be deeper than the thread groove when extruding pellets, and the length to diameter ratio should be taken as a large value. In the material for tube forming, the amount of lubricant and paraffin should not be too large, otherwise the output of extruded products will decrease because the material is easy to slip in the barrel. If the proportion of filling material in the preparation is too large, it is necessary to increase the proportion of lubricant accordingly.
54.2 PVC water supply pipe
PVC water supply pipe is extruded with special sanitary PVC grease,
It has the following characteristics.
① Non toxic, chemical resistant, not affected by chlorine or bleaching powder in water. ② It has strong water delivery capacity, small friction coefficient and small flow resistance to water. ③ Compared with other plastic pipes, it has better aging resistance and weather resistance. It does not scale and rust when used in water temperature below 50 ℃ for a long time. ④ It is non flammable and can be self extinguished from the fire source.
⑤ The pipes are easy to install and cheap.
(1) PVC resin for drinking water pipe molding shall be PVC SG5 resin (k value is 68 ~ 70, average polymerization degree is 1000) by suspension method. The content of vinyl chloride monomer in the resin shall be less than or equal to 3mg / kg. The maximum allowable content of lead, cadmium and mercury in auxiliary material stabilizer and lubricant is 0.005mg/l.
Reference formula (parts by mass) of the extruded tube by single screw extruder.
Polyvinyl chloride (PVC SG5) 100 dibasic lead phosphite (2PbO) 2
Tribasic lead sulfate (3PbO)
Molding process of two city lead phosphite (2PbO) and lead stearate (PBS () (2)
① Production process sequence of extrusion molding of PVC conveying drinking water pipe production process sequence of pipe molding with single screw extruder
PVC resin screening: metering of various raw materials in the formula → high-speed hot mixing of raw materials → cooling of raw materials, stirring, extrusion and granulation → extrusion and melting of raw materials → mold forming, tube blank → cooling and finalization → traction → cutting and inspection
Quality → weighing personnel warehouse
(6) tube forming process: PVC resin screening → metering of various raw materials in the formula → high-speed hot mixing of raw materials → cooling and mixing of raw materials → extrusion and melting with twin-screw extruder → mold forming of tube blank → cooling and finalization → traction → cutting → quality inspection → weighing inspection warehouse
② Refer to Chapter 4 for production process conditions of raw material blending and extrusion granulation. ③ Process temperature
a. The process temperature of single screw extrusion tube is 100 ~ 140 ℃ in barrel feeding section, 150 ~ 170 ℃ in plasticizing section and 160 ~ 180 ℃ in homogenizing section. The molding die temperature is 170 ~ 190 ℃. b. Process temperature of twin screw extrusion tube
@The process temperature of the counter rotating meshing twin-screw extrusion molding pipe is 130 ~ 160 ℃ in the feeding section, 150 ~ 155 ℃ in the plasticizing section and 160 ~ 170 ℃ in the homogenizing section. Molding die 170~
180℃。
The process temperature of conical twin-screw extrusion tube is 180 ~ 195 ℃ in the feeding section, 170 ~ 180 ℃ in the plasticizing section, and 1 molding die
It can be divided into two parts: the raw material preparation and supply system and the extrusion PVC pipe production system. The raw material supply system is the raw material supply system for extrusion PVC pipe
Production process sequence of main raw materials (PVC resin and auxiliary raw materials):
(1) Resin and various auxiliary raw materials shall be measured according to the material formula for pipe forming → in the high-speed hot mixer
② The production system of extruded PVC pipe products shall be evenly mixed → the raw materials shall be cooled, stirred and cooled → the extruder shall be used for mixing and granulation → the materials shall be fed into the extruder from the storage bin (c) → the extruder shall extrude the raw materials into a molten state → the pipe blank shall be formed through the molding die → cooling and finalization → traction → cutting → quality inspection → weighing and warehousing
(2) Raw material selection: the main raw material for PVC pipe extrusion molding is suspension polyene SG4 or SG5 type resin, which is combined with a variety of auxiliary materials (additives) as follows (see also table 4-5 for examples). Formula I (mass fraction)
(2PbO) real estate service (p6st) of national Yelin glue
Extruder. Refer to table 3-7 for outgoing specifications; The structure is that when the mixed raw materials are extruded and granulated, the general-purpose single screw can be used
(3) Preparation
Pitch gradient type, length diameter ratio L / D - (20 ~ 25): 1, compression ratio 2.5 ~ 4. If the powder is extruded directly, a round twin-screw extruder should be selected. Single screw or twin screw
The structure of PVC pipe mold is shown in Fig. 5-3. The composition of the extrusion line for forming hard PVC pipes is shown in Fig. 51. Refer to Chapter 4 for forming hard (4) and workpiece. Extrusion process temperature of UPVC pipe. From the barrel feeding section to the homogenizing section, the temperature is 100 ~ 140 ℃, 150 ~ 170 ℃ and 160 ~ 180 ℃. The molding die temperature is 170 ~ 185 ℃. (5) The quality of general UPVC pipes shall meet the requirements of gb1302091. See table 5-38 for the heterodyne. The length of the pipe is generally 4m, or more than 6m according to the user's requirements.
Case 5: plastic pipe bridge out molding
Physicalization of UPVC pipes for industrial use (gbt42191996)
Use general-purpose single ground line
Indicator indicator name indicator
< 1.55 longitudinal retraction /% ≤ 5
≤ 1.50 flat acetone immersion, no delamination, no fragmentation, no crack, no fracture
No fracture, no leakage ≥ 80 tensile yield stress / MPa ≥ 45
(refer to the fourth meaning)
The homogenization sections are,
4210-196
185℃。
Average external light limit deviation / mm nominal pressure (temperature: 0 ~ 25 ℃) / MPA 221
Bim pa0.4 pa0.6 pn0.8 pn1.0 pn1.6
Piping array
S16.0 S10.5 S8.0 S6.3 S4.0
Wall thickness (E / mm)
Limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value limit deviation of nominal value discoloration line and other phenomena; The dimensional error of wall thickness shall conform to the provisions in table 5-4; End face stress of pipe
20.1 + 2.3 straighten the pipe axis.
(6) Key points of process operation
① When the metered raw materials are mixed with a high-speed mixer, they must be mixed according to the process requirements
+2.80
7.9 + 3.0 mass. Mix and stir according to the required feeding sequence to ensure the mixing of PVC resin and other auxiliary materials
@When forming white PVC pipes, the titanium dioxide (TiO2) in the formula should be put into use within 2min before the end of the high-speed mixing process to avoid reducing the whiteness of titanium dioxide.
① Note that the heating temperature of the high-speed mixer should not be higher than 45 ℃ when mixing materials; After cooling down, deyihua real estate will assemble bars and molds, and prepare to produce. After learning from Hong Kong, the Australian compound should be in a loose state, and the material temperature should be lower than 45 ℃ When the machine needs to stop production for a long time due to the removal of residual materials, Fang Hai should be asked to rectify and clean it immediately. When the operator is not allowed to operate ⑥ in the direction of the outlet, he should observe the extruded materials from the outlet to prevent them from being damaged by the decomposition of smoke materials.
Jane's heating temperature. Bright and elastic indicates that the plasticization of raw materials has reached the quality, otherwise the machine should be properly improved. If the single screw extruder uses powder to extrude and form pipes, it should be noted that the thread depth and length to weight ratio of the screw should be deeper than the thread groove when extruding pellets, and the length to diameter ratio should be taken as a large value. In the material for tube forming, the amount of lubricant and paraffin should not be too large, otherwise the output of extruded products will decrease because the material is easy to slip in the barrel. If the proportion of filling material in the preparation is too large, it is necessary to increase the proportion of lubricant accordingly.
54.2 PVC water supply pipe
PVC water supply pipe is extruded with special sanitary PVC grease,
It has the following characteristics.
① Non toxic, chemical resistant, not affected by chlorine or bleaching powder in water. ② It has strong water delivery capacity, small friction coefficient and small flow resistance to water. ③ Compared with other plastic pipes, it has better aging resistance and weather resistance. It does not scale and rust when used in water temperature below 50 ℃ for a long time. ④ It is non flammable and can be self extinguished from the fire source.
⑤ The pipes are easy to install and cheap.
(1) PVC resin for drinking water pipe molding shall be PVC SG5 resin (k value is 68 ~ 70, average polymerization degree is 1000) by suspension method. The content of vinyl chloride monomer in the resin shall be less than or equal to 3mg / kg. The maximum allowable content of lead, cadmium and mercury in auxiliary material stabilizer and lubricant is 0.005mg/l.
Reference formula (parts by mass) of the extruded tube by single screw extruder.
Polyvinyl chloride (PVC SG5) 100 dibasic lead phosphite (2PbO) 2
Tribasic lead sulfate (3PbO)
Molding process of two city lead phosphite (2PbO) and lead stearate (PBS () (2)
① Production process sequence of extrusion molding of PVC conveying drinking water pipe production process sequence of pipe molding with single screw extruder
PVC resin screening: metering of various raw materials in the formula → high-speed hot mixing of raw materials → cooling of raw materials, stirring, extrusion and granulation → extrusion and melting of raw materials → mold forming, tube blank → cooling and finalization → traction → cutting and inspection
Quality → weighing personnel warehouse
(6) tube forming process: PVC resin screening → metering of various raw materials in the formula → high-speed hot mixing of raw materials → cooling and mixing of raw materials → extrusion and melting with twin-screw extruder → mold forming of tube blank → cooling and finalization → traction → cutting → quality inspection → weighing inspection warehouse
② Refer to Chapter 4 for production process conditions of raw material blending and extrusion granulation. ③ Process temperature
a. The process temperature of single screw extrusion tube is 100 ~ 140 ℃ in barrel feeding section, 150 ~ 170 ℃ in plasticizing section and 160 ~ 180 ℃ in homogenizing section. The molding die temperature is 170 ~ 190 ℃. b. Process temperature of twin screw extrusion tube
@The process temperature of the counter rotating meshing twin-screw extrusion molding pipe is 130 ~ 160 ℃ in the feeding section, 150 ~ 155 ℃ in the plasticizing section and 160 ~ 170 ℃ in the homogenizing section. Molding die 170~
180℃。
The process temperature of conical twin-screw extrusion tube is 180 ~ 195 ℃ in the feeding section, 170 ~ 180 ℃ in the plasticizing section, and 1 molding die
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