Extrusion molding of propylene pipe
DATE：2022/8/31 8:58:40 / READ： / SOURCE：This station
Extrusion molding of propylene pipe
Rockwell hardness bending modulus / MPA 90 1350 79.6 1081 71.2 1041 633 64.8 824
Bending strength / MPa
Thermal deformation temperature / ℃ Vicat softening point / ℃ 105 90 155 148 70.9
8a is good, and the circumferential stress under high temperature conditions is better stable than other polypropylene pipes. Under the conditions of 60 ℃ and 1.25mpa, the service life can reach more than 50 years.
have
It has the advantages of good heat preservation effect, smooth inner wall and small liquid flow resistance when hot water is transported
It is difficult to process the pipe after melting. However, due to the low melt flow rate of the resin, the viscosity of the melt is large, which gives the resin
(2) Resin conditions for C molding: random polypropylene resin with ethylene content of about 3% (mass) shall be selected as the material for C extrusion molding pipe. It is granular, with density in the range of 0.89-0.91g/cm, high particle weight, and melt flow rate (MFR) less than 05g / 10min
The parameter value shall meet the conditions in table 5-35.
(3) The extrusion molding process of type C equipment Part C is the same as that of ordinary polypropylene pipe. Single screw universal extruders are used. After the raw materials are extruded and melted, they are extruded from the molding die and then cooled and shaped by the vacuum sizing method. After the pipes are cooled by sufficient spray water, they are cut according to the collar length. Thereby completing the extrusion molding production of the random copolymer polypropylene pipe. Due to the low thermal conductivity, high molecular weight and low melt flow rate of the random copolymer polypropylene resin, that is, the viscosity of the resin in the molten state is high, so it needs more heat from the crystal to the high elastic state and then to the molten viscous flow state in the extrusion process, that is, the power consumption is large; The transformation process of raw material form has some special requirements on the structure of equipment
The screw structure is of constant pitch and varying depth, and the length diameter ratio is greater than
The structure is generally 331 in length diameter ratio, and the homogenization section of the screw is equipped with barrier type mixing
To ensure that the raw materials in the feeding section can be smoothly advanced by the screw screw. There is a central hole drilled in the body of the machine, which can pass cooling water to facilitate the working temperature of the screw. Longitudinal grooves evenly distributed on the circumference are opened at the different material sections of the working surface of the inner hole of the simple structure machine barrel and the working surface of the inner hole of the ordinary machine barrel to increase the thickness of the thick material and
The range is 1 ~ 3mm, and the length value is about 3 ~ 4 times of the inner diameter of the barrel. The surface friction improves the forward conveying capacity of raw materials after entering the machine. Longitudinal groove
Mold structure for forming pipes: the random polypropylene pipe shall be formed with basket or C-shaped mold (see Fig. 5-16 for basket shaped mold). The cavity of the melt flow channel is not large, the compression ratio is about 25:1, and the length of the straight part of the shaping section is longer than that of ordinary polypropylene
。 Note that the contraction angle of the mandrel shall not be too large. Or the length value of the straight part of the shaping section for molding is larger. The inner diameter of the die is larger than the inner diameter of the sizing sleeve. The length of the useful point is larger than the length value of the vacuum sizing sleeve of the common polypropylene tube blank. The specific length should be ④ the vacuum sizing sleeve and the cooling water tank structure. The random copolymer polypropylene tube blank is vacuum sizing
For example, when the diameter of the production pipe is 30mm, the length of the vacuum warp sleeve should not be less than 350mm. The vacuum degree in the vacuum sizing sleeve is controlled within the range of -0.09 ~ 406mpa of resin. The temperature of cooling circulating water in the vacuum jacket shall be adjustable, and the water temperature gauge is generally controlled at about 35 ℃. The length of the spray water tank is longer than that of the common polypropylene pipe cooling and temperature reduction performance base water tank: when the diameter of the production pipe is 30mm, the length of the spray water tank shall not be less than m; when the diameter of the production pipe is 50mm, the length of the spray water tank shall not be less than 12m. The spray water pipe can be divided into several sections, which is convenient for the temperature control of the cooling water. Random copolymerized polypropylene is a pipe extrusion molding production line, and the length of spray water tank can be up to 30m. The temperature of circulating water in the spray water tank is generally controlled at about 17 ℃. The water temperature of each section of the water tank shall be controlled according to the water temperature specified in the specification. The water temperature shall be gradually reduced from the time when the pipe blank enters the spray water tank after sizing. The inner diameter of the vacuum sizing sleeve should be slightly larger than the outer diameter of the forming pipe, but slightly smaller than the inner diameter of the die in the forming flow die.
At present, most of the domestic production lines of random copolymer polypropylene tube extruders are imported
Standby, high degree of automation, set, record and control by computer; The feeding port is equipped with an electronic scale for measurement, and the back of the sizing sleeve is equipped with a far-infrared measuring device to measure the diameter and wall of the pipe
The melting temperature of PP resin (about 170 ℃) shall be controlled to be stable and stable
The force of compressed air shall be controlled within 0.005MPa when the agent is collected; When it is used, the general clearance is 0.09
Within the range of 06mpa.
④ Pay attention to the relationship between the speed and the traction speed when the tube blank is extruded into the die mouth, i
% -5%。 The speed at which the tractor pulls and cools the finalized tube is faster than that at which the tube blank is extruded from the die mouth
⑤ PP molding stress is produced by the method of empty sizing
532 modified polypropylene pipe (the pipe is taken as the smaller diameter pipe). The sizing method can ensure the forming quality of pipes. The length of the sizing sleeve is about 4 times of the pipe diameter
Modified polypropylene refers to the resin obtained by changing the properties of polypropylene resin through physical or chemical methods, or giving new functions to materials. The pipes produced with modified polypropylene as the main raw material are modified polypropylene pipes. The modified polypropylene pipe not only has good acid resistance, alkali resistance, chemical corrosion resistance and heat resistance, but also has low temperature impact resistance, aging resistance and light resistance.
The purpose of the modified polypropylene pipe is the same as that of the ordinary polypropylene pipe, and it is better than the ordinary carnene pipe for Xinghai pumeng · LAN
The main raw material of the linear inner tube shall be the marriage body mobile vehicle, and the modified high material paving aids can make up for some of the shortcomings of kangnei resin.
(2) The material composition is known from the auxiliary material polybutadiene rubber and other auxiliary materials (LDPE) in the formula
The specific production process sequence is, etc.) can be greatly different, so the mixing and granulation of materials are divided into two parts
Polypropylene resin + LDPE + CaCO mixed
The polybutadiene secondary explosive rubber is mixed into flakes on the open mill, pelletized and mixed → preparation of materials for extrusion of modified polypropylene pipe. First, polypropylene resin, low-density ethylene and other additives are measured according to the formula conditions of the materials and mixed uniformly in the mixer. The polybutadiene rubber is molded into pieces on the open mill, and then pelletized. According to the requirements of the formula, the uniform particles of polytdiene are metered and then added into the polypropylene mixture and mixed evenly. The mixture is mixed and granulated by an extruder. This mixed pellet can be extruded to form modified polypropylene pipes. When the modified polypropylene pipes are used to transport drinking water, the performance requirements of the molding materials are shown in table 5-2 (3). Equipment conditions and process temperature when the modified polypropylene pipes are extruded by a single screw extruder, there are no special requirements on the structure of the screw. The screw used for extruding ordinary polypropylene resin can be used. Process temperature of each section of barrel: 140 ~ 160 ℃ in feeding section, 170 ~ 190 ℃ in plasticizing section and 190 ~ 210 ℃ in homogenizing section. The molding die temperature is 210 ~ 230 ℃.
(4) The extrusion process conditions of modified polypropylene water supply pipe are basically the same as those of ordinary polypropylene water supply pipe. The formula combination of the Department is as follows (parts by mass).
Polypropylene pellet (C4220, produced by Beijing Yanshan Petrochemical Co., Ltd., melt flow rate A3 ~ 0.4g/10min) 100 parts; 3 parts of ethylene vinyl acetate pellet (E / VAC, produced by France Tuo company, with a melt flow rate of 1G / 10min); EPDM pellet (produced by Lanzhou Petrochemical Company, melt flow rate 0.14g/10min) 3 parts; The flow rate of graft copolymer particles is 0.9-15g / 10min) 4.5 phr; Calcium carbonate (CaCO3) 5: in addition, there are antioxidants, light stabilizers, calcium stearate and other auxiliary materials, which can be appropriate
Extrusion molding process and operation precautions of modified polypropylene water supply pipe. Add people.
① The main material polypropylene and auxiliary materials are mixed together after being measured according to the formula requirements, and mixed evenly with a mixer.
② After the raw materials are mixed evenly, they are mixed and plasticized by an extruder (the melting temperature is between 200 and 215 ℃) and then extruded and granulated.
③ The extrusion molding of the modified polypropylene water supply pipe should select the screw with the length diameter ratio greater than 30:1
Rockwell hardness bending modulus / MPA 90 1350 79.6 1081 71.2 1041 633 64.8 824
Bending strength / MPa
Thermal deformation temperature / ℃ Vicat softening point / ℃ 105 90 155 148 70.9
8a is good, and the circumferential stress under high temperature conditions is better stable than other polypropylene pipes. Under the conditions of 60 ℃ and 1.25mpa, the service life can reach more than 50 years.
have
It has the advantages of good heat preservation effect, smooth inner wall and small liquid flow resistance when hot water is transported
It is difficult to process the pipe after melting. However, due to the low melt flow rate of the resin, the viscosity of the melt is large, which gives the resin
(2) Resin conditions for C molding: random polypropylene resin with ethylene content of about 3% (mass) shall be selected as the material for C extrusion molding pipe. It is granular, with density in the range of 0.89-0.91g/cm, high particle weight, and melt flow rate (MFR) less than 05g / 10min
The parameter value shall meet the conditions in table 5-35.
(3) The extrusion molding process of type C equipment Part C is the same as that of ordinary polypropylene pipe. Single screw universal extruders are used. After the raw materials are extruded and melted, they are extruded from the molding die and then cooled and shaped by the vacuum sizing method. After the pipes are cooled by sufficient spray water, they are cut according to the collar length. Thereby completing the extrusion molding production of the random copolymer polypropylene pipe. Due to the low thermal conductivity, high molecular weight and low melt flow rate of the random copolymer polypropylene resin, that is, the viscosity of the resin in the molten state is high, so it needs more heat from the crystal to the high elastic state and then to the molten viscous flow state in the extrusion process, that is, the power consumption is large; The transformation process of raw material form has some special requirements on the structure of equipment
The screw structure is of constant pitch and varying depth, and the length diameter ratio is greater than
The structure is generally 331 in length diameter ratio, and the homogenization section of the screw is equipped with barrier type mixing
To ensure that the raw materials in the feeding section can be smoothly advanced by the screw screw. There is a central hole drilled in the body of the machine, which can pass cooling water to facilitate the working temperature of the screw. Longitudinal grooves evenly distributed on the circumference are opened at the different material sections of the working surface of the inner hole of the simple structure machine barrel and the working surface of the inner hole of the ordinary machine barrel to increase the thickness of the thick material and
The range is 1 ~ 3mm, and the length value is about 3 ~ 4 times of the inner diameter of the barrel. The surface friction improves the forward conveying capacity of raw materials after entering the machine. Longitudinal groove
Mold structure for forming pipes: the random polypropylene pipe shall be formed with basket or C-shaped mold (see Fig. 5-16 for basket shaped mold). The cavity of the melt flow channel is not large, the compression ratio is about 25:1, and the length of the straight part of the shaping section is longer than that of ordinary polypropylene
。 Note that the contraction angle of the mandrel shall not be too large. Or the length value of the straight part of the shaping section for molding is larger. The inner diameter of the die is larger than the inner diameter of the sizing sleeve. The length of the useful point is larger than the length value of the vacuum sizing sleeve of the common polypropylene tube blank. The specific length should be ④ the vacuum sizing sleeve and the cooling water tank structure. The random copolymer polypropylene tube blank is vacuum sizing
For example, when the diameter of the production pipe is 30mm, the length of the vacuum warp sleeve should not be less than 350mm. The vacuum degree in the vacuum sizing sleeve is controlled within the range of -0.09 ~ 406mpa of resin. The temperature of cooling circulating water in the vacuum jacket shall be adjustable, and the water temperature gauge is generally controlled at about 35 ℃. The length of the spray water tank is longer than that of the common polypropylene pipe cooling and temperature reduction performance base water tank: when the diameter of the production pipe is 30mm, the length of the spray water tank shall not be less than m; when the diameter of the production pipe is 50mm, the length of the spray water tank shall not be less than 12m. The spray water pipe can be divided into several sections, which is convenient for the temperature control of the cooling water. Random copolymerized polypropylene is a pipe extrusion molding production line, and the length of spray water tank can be up to 30m. The temperature of circulating water in the spray water tank is generally controlled at about 17 ℃. The water temperature of each section of the water tank shall be controlled according to the water temperature specified in the specification. The water temperature shall be gradually reduced from the time when the pipe blank enters the spray water tank after sizing. The inner diameter of the vacuum sizing sleeve should be slightly larger than the outer diameter of the forming pipe, but slightly smaller than the inner diameter of the die in the forming flow die.
At present, most of the domestic production lines of random copolymer polypropylene tube extruders are imported
Standby, high degree of automation, set, record and control by computer; The feeding port is equipped with an electronic scale for measurement, and the back of the sizing sleeve is equipped with a far-infrared measuring device to measure the diameter and wall of the pipe
The melting temperature of PP resin (about 170 ℃) shall be controlled to be stable and stable
The force of compressed air shall be controlled within 0.005MPa when the agent is collected; When it is used, the general clearance is 0.09
Within the range of 06mpa.
④ Pay attention to the relationship between the speed and the traction speed when the tube blank is extruded into the die mouth, i
% -5%。 The speed at which the tractor pulls and cools the finalized tube is faster than that at which the tube blank is extruded from the die mouth
⑤ PP molding stress is produced by the method of empty sizing
532 modified polypropylene pipe (the pipe is taken as the smaller diameter pipe). The sizing method can ensure the forming quality of pipes. The length of the sizing sleeve is about 4 times of the pipe diameter
Modified polypropylene refers to the resin obtained by changing the properties of polypropylene resin through physical or chemical methods, or giving new functions to materials. The pipes produced with modified polypropylene as the main raw material are modified polypropylene pipes. The modified polypropylene pipe not only has good acid resistance, alkali resistance, chemical corrosion resistance and heat resistance, but also has low temperature impact resistance, aging resistance and light resistance.
The purpose of the modified polypropylene pipe is the same as that of the ordinary polypropylene pipe, and it is better than the ordinary carnene pipe for Xinghai pumeng · LAN
The main raw material of the linear inner tube shall be the marriage body mobile vehicle, and the modified high material paving aids can make up for some of the shortcomings of kangnei resin.
(2) The material composition is known from the auxiliary material polybutadiene rubber and other auxiliary materials (LDPE) in the formula
The specific production process sequence is, etc.) can be greatly different, so the mixing and granulation of materials are divided into two parts
Polypropylene resin + LDPE + CaCO mixed
The polybutadiene secondary explosive rubber is mixed into flakes on the open mill, pelletized and mixed → preparation of materials for extrusion of modified polypropylene pipe. First, polypropylene resin, low-density ethylene and other additives are measured according to the formula conditions of the materials and mixed uniformly in the mixer. The polybutadiene rubber is molded into pieces on the open mill, and then pelletized. According to the requirements of the formula, the uniform particles of polytdiene are metered and then added into the polypropylene mixture and mixed evenly. The mixture is mixed and granulated by an extruder. This mixed pellet can be extruded to form modified polypropylene pipes. When the modified polypropylene pipes are used to transport drinking water, the performance requirements of the molding materials are shown in table 5-2 (3). Equipment conditions and process temperature when the modified polypropylene pipes are extruded by a single screw extruder, there are no special requirements on the structure of the screw. The screw used for extruding ordinary polypropylene resin can be used. Process temperature of each section of barrel: 140 ~ 160 ℃ in feeding section, 170 ~ 190 ℃ in plasticizing section and 190 ~ 210 ℃ in homogenizing section. The molding die temperature is 210 ~ 230 ℃.
(4) The extrusion process conditions of modified polypropylene water supply pipe are basically the same as those of ordinary polypropylene water supply pipe. The formula combination of the Department is as follows (parts by mass).
Polypropylene pellet (C4220, produced by Beijing Yanshan Petrochemical Co., Ltd., melt flow rate A3 ~ 0.4g/10min) 100 parts; 3 parts of ethylene vinyl acetate pellet (E / VAC, produced by France Tuo company, with a melt flow rate of 1G / 10min); EPDM pellet (produced by Lanzhou Petrochemical Company, melt flow rate 0.14g/10min) 3 parts; The flow rate of graft copolymer particles is 0.9-15g / 10min) 4.5 phr; Calcium carbonate (CaCO3) 5: in addition, there are antioxidants, light stabilizers, calcium stearate and other auxiliary materials, which can be appropriate
Extrusion molding process and operation precautions of modified polypropylene water supply pipe. Add people.
① The main material polypropylene and auxiliary materials are mixed together after being measured according to the formula requirements, and mixed evenly with a mixer.
② After the raw materials are mixed evenly, they are mixed and plasticized by an extruder (the melting temperature is between 200 and 215 ℃) and then extruded and granulated.
③ The extrusion molding of the modified polypropylene water supply pipe should select the screw with the length diameter ratio greater than 30:1
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