CN216732941U

CN216732941U - Special screw rod of high-efficient polyethylene pipe extruder

Info

Publication number: CN216732941U
Application number: CN202123125964.3U
Authority: CN
Inventors: 黄伟红; 庄乾; 王志军
Original assignee: Zhejiang Jinhai Plastic Machinery Co ltd
Current assignee: Zhejiang Jinhai Plastic Machinery Co ltd
Priority date: 2021-12-10
Filing date: 2021-12-10
Publication date: 2022-06-14
Anticipated expiration: 2031-12-10

Abstract

The utility model relates to a special screw rod for a high-efficiency polyethylene pipe extruder, which comprises a screw rod, the screw rod is sequentially divided into a feeding section, a separation type compression section, a metering section, a barrier section and a mixing section along the length direction from feeding to discharging, main spiral sheets are arranged on the screw rod cylindrical surfaces of the feeding section, the separation type compression section and the metering section along the length direction, a spiral groove and a main spiral edge are formed between the main spiral sheets and the screw rod, an auxiliary spiral sheet playing a role of a barrier is further arranged on the separated compression section, the outer diameter of the auxiliary spiral sheet is smaller than that of the main spiral sheet, the main screw ridge lead and the auxiliary screw ridge lead of the separated compression section are both larger than that of the feeding section, the main screw ridge lead and the auxiliary screw ridge lead of the separated compression section are both 1.3-1.6 times of that of the feeding section, the main screw ridge lead of the feeding section is of an equidistant, increasing and equidistant gradual change type structure, and the length-diameter ratio of the screw is 38: 1-40: 1. The screw can ensure that the raw materials can pass through smoothly, reduce the backflow of plastics and improve the feeding amount.

Description

Special screw rod of high-efficient polyethylene pipe extruder

Technical Field

The utility model relates to a belong to macromolecular material processing machinery technical field, relate to a screw rod structure of extruder, especially relate to a special screw rod of high-efficient polyethylene pipe extruder.

Background

The extruder is used for fully mixing and extruding various particle raw materials and outputting the raw materials, and is mainly used in the field of plastic or rubber manufacturing. When the extruder is in operation, the raw materials are heated to be viscous flow, and under the condition of pressurization, the raw materials are made to pass through a neck mould with a certain shape to form a continuous body with a cross section similar to the shape of the neck mould, then the continuous body is cooled to enable the raw materials with a certain geometric shape and size to be changed from a viscous flow state to a high elastic state, and finally the raw materials are cooled and shaped to be glass state, so that the required product is obtained.

A high-efficiency polyethylene pipe extruder is characterized in that Polyethylene (PE) plastics enter a containing cavity between a screw and a machine barrel through a feed opening of the extruder, thrust perpendicular to an inclined edge surface is generated on the plastics through the inclined edge surface rotated by the screw, the plastics are pushed forwards, in the pushing process, due to friction between the plastics and the screw, between the plastics and the machine barrel and friction between particles, the machine barrel is heated to be gradually melted, the melted plastics are extruded through a die, and qualified products are produced through a sizing sleeve and a vacuum cooling box. The screw of the existing standard extruder is easy to have overlarge mechanical energy at the beginning of a separation compression section, so that raw materials cannot pass smoothly; and the plasticizing is not complete, the surface of the pipe is not uniform, and the pipe has crystal points. Meanwhile, the screw is easy to generate backflow in the feeding section to influence the feeding.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a special screw rod of high-efficient polyethylene pipe extruder is provided to above-mentioned prior art, have that structural design is reasonable, the shearing melting is abundant, product quality is good, high yield's characteristics.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: the utility model provides a special screw rod of high-efficient polyethylene pipe extruder, includes the screw rod, its characterized in that: the screw is sequentially divided into a feeding section, a separated compression section, a metering section, a barrier section and a mixing section along the length direction from feeding to discharging, the cylindrical surfaces of the screws of the feeding section, the separated compression section and the metering section are provided with main spiral sheets along the length direction, a spiral groove and a main spiral edge are formed between the main spiral sheets and the screws, an auxiliary spiral sheet which has the function of a barrier and separates solid plastic from molten plastic is arranged on the separated compression section, the outer diameter of the auxiliary spiral sheet is smaller than that of the main spiral sheet, wherein the main screw ridge lead and the auxiliary screw ridge lead of the separated compression section are both larger than the main screw ridge lead of the feeding section, the main screw ridge lead and the auxiliary screw ridge lead of the separated compression section are both 1.3-1.6 times of the main screw ridge lead of the feeding section, the lead of the main screw ridge of the feeding section is of a gradual change structure with equal distance, increase and equal distance, and the length-diameter ratio of the screw is 38: 1-40: 1.

As an improvement, the auxiliary spiral piece divides the spiral groove on the separated compression section into a molten state area spiral groove and a solid state area spiral groove, molten plastic enters the molten state area through the outer diameter of the auxiliary spiral piece, the width of the solid state area spiral groove is gradually narrowed, the depth of the solid state area spiral groove is gradually reduced, the width of the molten state area spiral groove is gradually widened, the depth of the molten state area spiral groove is gradually deepened and then reduced, and finally the molten state area spiral groove is flush with the depth of the spiral groove of the metering section.

As an improvement, a plurality of longitudinal grooves are equidistantly formed in the cylindrical surface of the screw rod of the barrier section, the longitudinal grooves are divided into two groups, namely a feeding groove and a discharging groove, the two groups of longitudinal grooves are arranged at intervals, the outlet of the feeding groove is closed in the axis direction, and the inlet of the discharging groove is closed in the axis direction.

Preferably, the external diameter of the thread between the feed chute and the discharge chute is smaller than the diameter of the screw.

Furthermore, one row or a plurality of rows of pins are arranged on the cylindrical surface of the screw rod of the mixing section.

Preferably, the pins are 3-4 rows of cylindrical or square pins.

Preferably, the length of the separate type compression section is 38% to 42% of the total length of the screw.

Preferably, the length to diameter ratio of the screw is 38:1, the length-diameter ratio of the feeding section is 14: 1, the length-diameter ratio of the separated compression section is 15:1, the length-diameter ratio of the metering section is 2:1, and the length-diameter ratio of the barrier section is 3.5: 1, the length-diameter ratio of the mixing section is 3.5: 1.

compared with the prior art, the utility model has the advantages of: the structure of the screw is reasonably designed, the compression section is designed into a separation type compression section, and an auxiliary thread playing a role of a barrier is additionally arranged on the separation type compression section, so that the polyethylene plastic is molten in the screw in a molten state, and a solution containing small particles of unmelted solid flows to the separation type compression section to be subjected to high shearing and molten, and the melting rate is improved; the main screw lead and the auxiliary screw lead of the separated compression section are both larger than the main screw lead of the feeding section, so that the separated compression section cannot generate excessive mechanical energy, and the smooth passing of raw materials is ensured; in addition, the screw increases the size of the main screw ridge lead and the auxiliary screw ridge lead so as to improve the feeding amount. Set up protective screen section and mixing section for when melting the material and flowing through mixing section, produce and cut and generate heat, make not melting material melting, the main screw arris helical pitch of feeding section is equidistance, increase, the gradual change formula structure of equidistance simultaneously, can increase the backward flow that reduces plastics like this, has increased the load.

Drawings

Fig. 1 is a schematic structural view of a screw rod in an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

As shown in fig. 1, the screw dedicated for the high-speed polyethylene pipe extruder in this embodiment includes a screw 1, the screw 1 is sequentially divided into a feeding section a, a separation type compression section B, a metering section C, a barrier section D and a mixing section E along a length direction from feeding to discharging, helical fins are arranged on screw cylindrical surfaces of the feeding section a, the separation type compression section B and the metering section C along the length direction, and a helical groove 2a and a main helical rib 2B are formed between the helical fins and the screw 1; thus, the feeding section A ensures stable and non-heating feeding and uniform feeding, and the lead of the main screw ridge of the feeding section A is in a gradual change structure with equal distance, increase and equal distance, so that the backflow of plastics can be reduced, and the discharge amount is increased; meanwhile, the separated compression section B ensures that the raw materials can be fully sheared and stably extruded, and the barrier section D ensures that the raw materials which are not melted can be fully sheared and further plasticized; the mixing section E is for sufficiently mixing the raw materials, further performing a plasticizing effect, and ensuring stable extrusion. In the embodiment, the bottom diameter of the feeding section A is deepened by 10-20% compared with that of the existing screw, so that the feeding amount is increased; the bottom diameter of the metering section C is deepened by 6% -12% compared with that of the existing screw rod, so that the resistance is reduced, and the discharge amount is increased.

Wherein the depth of the screw grooves 2a of the feeding section A is the same, the depth of the screw grooves 2a of the compression section B is gradually reduced to the metering section C, and the depth of the screw grooves 2a of the metering section C is the same; an auxiliary spiral sheet 3 which has the function of a barrier and separates solid plastic from molten plastic is arranged on the separated compression section B, and the outer diameter of the auxiliary spiral sheet 3 is smaller than that of the main spiral sheet; the auxiliary spiral sheet 3 divides the spiral groove 2a on the separated compression section B into a molten zone spiral groove 3a and a solid zone spiral groove 3B, molten plastic enters the molten zone beyond the outer diameter of the auxiliary spiral sheet 3, the width of the solid zone spiral groove 3B is gradually narrowed, the depth of the solid zone spiral groove 3B is gradually reduced, the width of the molten zone spiral groove 3a is gradually widened, the depth of the molten zone spiral groove 3a is gradually reduced and then reduced, and finally the depth of the molten zone spiral groove 3a is leveled with the depth of the spiral groove 2B of the metering section C. Thus, when polyethylene plastic is in a molten state in the screw 1, a solution containing small particles of unmelted solid flows to the separation type compression section B and is melted by high shearing of the auxiliary spiral sheet 3, and the melting rate is improved; meanwhile, in the conveying process of the screw rod 1, materials can smoothly pass through the separation type compression section B when reaching the separation type compression section B, the blockage is not easy to occur, and the service life of the screw rod 1 is ensured.

In this embodiment, the main screw thread lead and the auxiliary screw thread lead of the separation type compression section B are both greater than the main screw thread lead of the feeding section a, and the main screw thread lead and the auxiliary screw thread lead of the separation type compression section B are 1.3 to 1.6 times of the main screw thread lead of the feeding section a, so that the separation type compression section B cannot generate too large mechanical energy, the problem that raw materials cannot pass through smoothly is avoided, and the productivity is improved.

Every barrier 5 of barrier section D corresponds and has seted up a plurality of longitudinal grooves on the screw rod face of cylinder equidistance, and longitudinal groove divide into feed chute and blown down tank two groups, and two longitudinal grooves of group are set up alternately, and wherein the export of feed chute is closed in the axis direction, and the entry of blown down tank is closed in the axis direction, and the external diameter of screw thread between feed chute and the blown down tank is less than screw rod 1 diameter. The utility model discloses the material of well measurement section is flowed in by the feed chute and is got into the blown down tank through less external diameter of thread, makes polyethylene plastics under 1 the inside molten state of screw rod, receives the shearing action when the dissolved material that contains not fused solid tiny particle flows to protective screen section D, and a large amount of mechanical energy becomes heat energy, makes not fused solid tiny particle melting, mix to fully cut the raw materials of measurement section C through protective screen section D, and further plastify and make the goods surface do not have brilliant point, and glossiness is good.

One or more rows of pins 4 are arranged on the cylindrical surface of the screw of the mixing section E, the pins 4 can be cylindrical or square pins, in the embodiment, the pins 4 are 4 rows and are arranged on the screw 1 at equal intervals. When the melted materials flow through the mixing section E, shearing heating is generated, the unmelted materials can be plasticized, and the gas in the melted materials is thinned and homogenized through shearing and mixing.

The length of the separation type compression section B accounts for 38-42% of the total length of the screw 1. In this example, the length-diameter ratio of the screw 1 was 38:1, the length-diameter ratio of the feeding section A is 14: 1, the length-diameter ratio of the separation type compression section B is 15:1, the length-diameter ratio of the metering section C is 2:1, and the length-diameter ratio of the barrier section D is 3.5: 1, the length-diameter ratio of the mixing section E is 3.5: 1.

in practical use, the feeding section A, the separated compression section B and the metering section C in the screw have increased raw material discharge amount compared with the existing screw, the screw in the embodiment is suitable for a motor of 132KW, the rotating speed is 150 revolutions per minute, the constant is 600Kg/h, meanwhile, the surface of a product is guaranteed to have no crystal points, the glossiness is good, the thickness is uniform, and the product quality is improved.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the technical principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a special screw rod of high-efficient polyethylene pipe extruder, includes the screw rod, its characterized in that: the screw is sequentially divided into a feeding section, a separation type compression section, a metering section, a barrier section and a mixing section along the length direction from feeding to discharging, the cylindrical surfaces of the screws of the feeding section, the separated compression section and the metering section are provided with main spiral sheets along the length direction, a spiral groove and a main spiral edge are formed between the main spiral sheets and the screws, the separated compression section is also provided with an auxiliary spiral sheet which plays a role of a barrier and separates solid plastic from molten plastic, the outer diameter of the auxiliary spiral sheet is smaller than that of the main spiral sheet, wherein the main screw ridge lead and the auxiliary screw ridge lead of the separated compression section are both larger than the main screw ridge lead of the feeding section, the main screw ridge lead and the auxiliary screw ridge lead of the separated compression section are both 1.3-1.6 times of the main screw ridge lead of the feeding section, the main screw ridge lead of the feeding section is of a gradient structure with equal distance, increasing and equal distance, and the length-diameter ratio of the screw is 38: 1-40: 1.

2. The special screw for the high efficiency polyethylene pipe extruder as claimed in claim 1, wherein: the auxiliary helical blade divides the helical groove on the separated compression section into a molten state area helical groove and a solid state area helical groove, molten plastic enters the molten state area after crossing the outer diameter of the auxiliary helical blade, the width of the solid state area helical groove is gradually narrowed, the depth of the solid state area helical groove is gradually reduced, the width of the molten state area helical groove is gradually widened, and the depth of the molten state area helical groove is gradually deepened, then is reduced and finally is connected with the depth of the helical groove of the metering section.

3. The special screw for the high efficiency polyethylene pipe extruder as claimed in claim 1, wherein: the screw rod cylindrical surface of barrier section is seted up a plurality of longitudinal grooves of equidistance, and longitudinal groove divide into feed chute and blown down tank two groups, and two longitudinal grooves of group are set up at intervals, and wherein the export of feed chute is closed in the axis direction, and the entry of blown down tank is closed in the axis direction.

4. The special screw for the high efficiency polyethylene pipe extruder as claimed in claim 3, wherein: and the outer diameter of the thread between the feed chute and the discharge chute is smaller than the diameter of the screw.

5. The special screw for the high efficiency polyethylene pipe extruder as claimed in claim 1, wherein: one or more rows of pins are arranged on the cylindrical surface of the screw of the mixing section.

6. The special screw for the high efficiency polyethylene pipe extruder as claimed in claim 5, wherein: the pins are 3-4 rows of cylindrical or square pins.

7. The special screw for the high-efficiency polyethylene pipe extruder as claimed in any one of claims 1 to 6, wherein: the length of the separated compression section accounts for 38-42% of the total length of the screw.

8. The special screw for the high-efficiency polyethylene pipe extruder as claimed in any one of claims 1 to 6, wherein: the length-diameter ratio of the screw is 38:1, the length-diameter ratio of the feeding section is 14: 1, the length-diameter ratio of the separated compression section is 15:1, the length-diameter ratio of the metering section is 2:1, and the length-diameter ratio of the barrier section is 3.5: 1, the length-diameter ratio of the mixing section is 3.5: 1.