CN110480973A - A kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber - Google Patents
A kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber Download PDFInfo
- Publication number
- CN110480973A CN110480973A CN201910806126.0A CN201910806126A CN110480973A CN 110480973 A CN110480973 A CN 110480973A CN 201910806126 A CN201910806126 A CN 201910806126A CN 110480973 A CN110480973 A CN 110480973A
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- Prior art keywords
- filter plate
- glass fiber
- reinforced polypropylene
- molding
- content
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0011—Combinations of extrusion moulding with other shaping operations combined with compression moulding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0018—Combinations of extrusion moulding with other shaping operations combined with shaping by orienting, stretching or shrinking, e.g. film blowing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
- B29C48/07—Flat, e.g. panels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/25—Solid
- B29K2105/251—Particles, powder or granules
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/14—Filters
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Filtering Materials (AREA)
Abstract
The present invention provides a kind of production methods of the modified reinforced polypropylene filter plate of high-content roving glass fiber, by the pellet of the modified reinforced polypropylene of high-content roving glass fiber, first moisture removal is removed through heated-air drying blender, it is squeezed out again by extruding machine melt, in the mold in the warmed-up heat preservation of direct quantitative filling, the mold after filler transports progressive die press, high pressure molding and pressure maintaining molding, molding filter plate blank is taken out in demoulding, is transferred to expanding machine compression and pressure maintaining sizing, filter plate blank is then cut into filter plate finished product.The filter plate production problem for having cracked the modified reinforced polypropylene of high-content roving glass fiber provides the filter plate of high-quality performance, long life for the filter press used under high temperature and high pressure condition, ensure that filter press high-efficiency and low-cost high reliability is run.
Description
Technical field
The present invention relates to technical field of solid-liquid separation equipment, and in particular to a kind of modified reinforced polypropylene of high-content roving glass fiber
The production method of filter plate.
Background technique
Primary filter element of the filter plate as filter press, quality parameter are directly related to the filter effect of filter press and make
Use the service life.Enlargement, lightweight, energy conservation and environmental protection, reduce the promotion of the theories such as cost under, most of filter press filter board material is all
Selection uses modified reinforced polypropylene, but the filter plate of currently used modified reinforced polypropylene production, it is difficult to meet high temperature and pressure
The requirement of filtering.
The improvement in terms of modified reinforced polypropylene new material domestic at present has some research and development, such as high-content
Roving glass fiber is modified reinforced polypropylene, has the good characteristics such as high intensity, high heat distortion temperature, high fluidity.But its fusion temperature
Narrow range is more suitable for the moulded manufacturability of pressure injection and injection.But based on the considerations of to cost, it is filter board mould that the country, which generallys use,
Molded technique, usually modified reinforced polypropylene are squeezed out by extruding machine melt, and melt extrusion is first stored in incubator inside holding, then
By filter plate blank weight weighing sub-material, compression molding in the preheated mold that then transhipment is filled on progressive die press, the process requirement
Otherwise wider fusion temperature range is easy to appear mobility and is deteriorated and difficult forming；In contrast, fusion temperature narrow range,
Melt has high fluidity in this temperature range, is easy to appear molding flash and influences the molding compactness of filter plate, on the other hand again
It is easy to appear and hinders molding accurate in place because of the too fast solidification of molding flash, generate waste product.Therefore, it is necessary to filter board compression molding
Process Exploration changes, and provides a kind of production method of modified reinforced polypropylene filter plate of high-content roving glass fiber.
Summary of the invention
The purpose of the present invention is to provide a kind of production methods of the modified reinforced polypropylene filter plate of high-content roving glass fiber, help
In improve the modified reinforced polypropylene Material Melt temperature narrow range of high-content roving glass fiber, cause in manufacturing process mobility be deteriorated and
The problem of difficult forming, while it is close to reduce molding flash caused by mobility height, influence filter plate molding within the scope of narrow temperature
The problem of solidity, the high-content roving glass fiber of production modified reinforced polypropylene filter plate meets filter press high temperature, high-pressure filteration makes
With requiring.
The present invention through the following technical solutions to achieve the above objectives:
A kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber, the filter plate are changed with high-content roving glass fiber
Property reinforced polypropylene pellet be raw material, production the following steps are included:
1) it takes raw material to stir 1~2h at 90~100 DEG C through heated-air drying blender, removes moisture removal；
2) pellet after moisture removal will be gone to place melt at 215~260 DEG C of extruding machine to squeeze out with the revolving speed of 30~60rmp,
In the mold of warmed-up 200~220 DEG C of the heat preservation of direct quantitative filling；
3) mold after filler is transported into progressive die press, high pressure molding, 1~2h pressure maintaining molding under 20~25MPa pressure；
4) molding filter plate blank is taken out in demoulding, lays flat to horizontal table and cools to 60~100 DEG C；
5) by the filter plate blank after cooling be transferred to expanding machine compressed under the pressure of 3~4MPa and pressure maintaining sizing 36~
48h；
6) filter plate blank is taken out from expanding machine, is laid flat more than after 72h, being cut into filter plate finished product.
Preferably, the extruding machine of the step 2) is single screw extrusion machine, and the extruding machine is divided into section, goes out section, centre
Three sections of section, temperature of each section is set as 215~260 DEG C, low into and out of section temperature, and interlude temperature is high.
Preferably, the mold of the step 3) is divided into upper mold and lower mold, and the melt that the extruding machine is squeezed out is by filter
The weighing of plate blank weight, the lower mould type that direct quantitative filling is preheated in heat preservation is intracavitary, then rapid transhipment progressive die press, with
Upper mold molding in preheating insulation, when molding, are automatically stopped the preheating insulation to upper mold.
Preferably, the machined both ends of the surface of filter plate blank, surrounding side and each hole of the step 6), be made filter plate at
After product, accumulation storage is laid flat.
Preferably, the heated-air drying blender can be the vertical heated-air drying blender of LSQF-1000 model；It is described
Moulding press can be the hydraulic column press of YZW32-10000T model；The expanding machine can be YZW32-1500T type
Number hydraulic column press.
Technical solution provided by the invention specifically has the advantages that compared with prior art:
1, by the melt of the modified reinforced polypropylene of high-content roving glass fiber, incubator turnover storage heat preservation, direct quantitative are not had to
It inserts in the mold of high preheating temperature, has cracked and be easy to appear molding hardly possible caused by mobility is deteriorated because of fusion temperature narrow range
Topic.
2, it is molded at a slow speed using pressure more higher than usual 10~20MPa and pressure maintaining molding, appropriateness adjusts melt table
Viscosity and control flash are seen, guarantees that each position even density of molding filter plate blank, consolidation, intensity are high.
3, the modified reinforced polypropylene filter plate of the high-content roving glass fiber made, quality parameter height, long service life, meets high temperature
Requirement under high pressure operating condition ensure that filter press high-efficiency and low-cost high reliability is run.
Specific embodiment
Embodiment 1:
1) it takes the pellet of the modified reinforced polypropylene PP-LGF20 of high-content roving glass fiber as raw material, is sucked by feeder
The vertical heated-air drying blender of LSQF-1000 model, circulation stirring 1h, uniformly removes moisture removal at 90 DEG C, to guarantee the later period
Filter plate blank pore-free, the material even density of compacting；
2) pellet after moisture removal will be gone by the hopper of filling machine sucking single screw extrusion machine, single screw extrusion machine into,
Section temperature setting is 220 DEG C out, and interlude is 255 DEG C, with this condition melt, is squeezed out with the revolving speed of 50rmp, the melt of extrusion
It weighs by filter plate blank weight, the lower mould type that direct quantitative filling has carried out 220 DEG C of preheating insulations is intracavitary, it is ensured that the stream of melt
Dynamic property；
3) the lower mold after filler is transported into rapidly the hydraulic column press into YZW32-10000T model, with 210 DEG C
Upper mold molding in preheating insulation, when molding, are automatically stopped upper mold preheating insulation, at a slow speed molding pressure, prevent and controls and is excessive
Material, final molding and the molding pressure of pressure maintaining are 22MPa, and pressure maintaining molding time is 1h, it is ensured that melt calendering flowing is full of mold
Type chamber, each section crystallization is sufficiently, density consolidation is consistent, shrinks uniformly, and curing molding is to demould；
4) molding filter plate blank is taken out in demoulding, lays flat to horizontal table and cools to 65 DEG C, so that inside filter plate blank
Institutional framework stress initial release balance；
5) the filter plate blank after cooling is transferred to the hydraulic column press of YZW32-1500T model, in the pressure of 3MPa
Lower compression and pressure maintaining sizing 36h, guarantee filter plate blank in cooling procedure, can balance internal organizational structure shrinkage stress as far as possible,
Control and reduction deflection, guarantee filter plate blank overall leveling after cooling；
6) filter plate blank is taken out from the hydraulic column press of YZW32-1500T model, is lain on horizontal table
Ageing treatment, laying flat the time is 72h, further discharges residual stress and residual deformation, then filter plate blank is passed through machining
Equipment machining both ends of the surface, surrounding side and each hole, become filter plate finished product, then lay flat accumulation storage.
Embodiment 2:
1) it takes the pellet of the modified reinforced polypropylene PP-LGF30LW of high-content roving glass fiber as raw material, is sucked by feeder
The vertical heated-air drying blender of LSQF-1000 model, circulation stirring 1h, uniformly removes moisture removal at 90 DEG C, to guarantee the later period
Filter plate blank pore-free, the material even density of compacting；
2) pellet after moisture removal will be gone by the hopper of filling machine sucking single screw extrusion machine, single screw extrusion machine into,
Section temperature setting is 220 DEG C out, and interlude is 255 DEG C, with this condition melt, is squeezed out with the revolving speed of 50rmp, the melt of extrusion
It weighs by filter plate blank weight, the lower mould type that direct quantitative filling has carried out 220 DEG C of preheating insulations is intracavitary, it is ensured that the stream of melt
Dynamic property；
3) the lower mold after filler is transported into rapidly the hydraulic column press into YZW32-10000T model, with 210 DEG C
Upper mold molding in preheating insulation, when molding, are automatically stopped upper mold preheating insulation, at a slow speed molding pressure, prevent and controls and is excessive
Material, final molding and the molding pressure of pressure maintaining are 22MPa, and pressure maintaining molding time is 1h, it is ensured that melt calendering flowing is full of mold
Type chamber, each section crystallization is sufficiently, density consolidation is consistent, shrinks uniformly, and curing molding is to demould；
4) molding filter plate blank is taken out in demoulding, lays flat to horizontal table and cools to 65 DEG C, so that inside filter plate blank
Institutional framework stress initial release balance；
5) the filter plate blank after cooling is transferred to the hydraulic column press of YZW32-1500T model, in the pressure of 3MPa
Lower compression and pressure maintaining sizing 36h, guarantee filter plate blank in cooling procedure, can balance internal organizational structure shrinkage stress as far as possible,
Control and reduction deflection, guarantee filter plate blank overall leveling after cooling；
6) filter plate blank is taken out from the hydraulic column press of YZW32-1500T model, is lain on horizontal table
Ageing treatment, laying flat the time is 72h, further discharges residual stress and residual deformation, then filter plate blank is passed through machining
Equipment machining both ends of the surface, surrounding side and each hole, become filter plate finished product, then lay flat accumulation storage.
Technical solution provided by the invention is compared as follows with filter plate performance data made of the prior art:
Claims (5)
1. a kind of modified reinforced polypropylene filter plate of high-content roving glass fiber and production method, which is characterized in that the filter plate is contained with height
The pellet for measuring the modified reinforced polypropylene of roving glass fiber is raw material, production the following steps are included:
1) it takes raw material to stir 1 ~ 2h at 90 ~ 100 DEG C through heated-air drying blender, removes moisture removal;
2) pellet after moisture removal will be gone to place melt at 215 ~ 260 DEG C of extruding machine to squeeze out with the revolving speed of 30 ~ 60rmp, directly calmly
In the mold of warmed-up 200 ~ 220 DEG C of the heat preservation of amount filling；
3) mold after filler is transported into progressive die press, high pressure molding, 1 ~ 2h pressure maintaining molding under 20 ~ 25MPa pressure；
4) molding filter plate blank is taken out in demoulding, lays flat to horizontal table and cools to 60 ~ 100 DEG C；
5) the filter plate blank after cooling expanding machine is transferred to compress under the pressure of 3 ~ 4MPa and 36 ~ 48h of pressure maintaining sizing；
6) filter plate blank is taken out from expanding machine, is laid flat more than after 72h, being cut into filter plate finished product.
2. a kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber according to claim 1, feature
It is, the extruding machine of the step 2 is single screw extrusion machine, and the extruding machine is divided into section, goes out section, three sections of interlude, each section
Temperature setting is 215 ~ 260 DEG C, low into and out of section temperature, and interlude temperature is high.
3. a kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber according to claim 1, feature
It is, the mold of the step 3) can be to be divided into upper mold and lower mold, and the melt that the extruding machine is squeezed out is by filter plate hair
The weighing of base weight, the lower mould type that direct quantitative filling is preheated in heat preservation is intracavitary, then rapid transhipment progressive die press, with preheating
Upper mold molding in heat preservation, when molding, are automatically stopped the preheating insulation to upper mold.
4. a kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber according to claim 1, feature
It is, the machined both ends of the surface of filter plate blank, surrounding side and each hole of the step 6) are laid flat after filter plate finished product is made
Accumulation storage.
5. a kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber according to claim 1, feature
Be: the heated-air drying blender can be the vertical heated-air drying blender of LSQF-1000 model；The moulding press can be with
For the hydraulic column press of YZW32-10000T model；The expanding machine can be the hydraulic of YZW32-1500T model
Column press.
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| CN201910806126.0A CN110480973A (en) | 2019-08-29 | 2019-08-29 | A kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber |
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| CN201910806126.0A CN110480973A (en) | 2019-08-29 | 2019-08-29 | A kind of production method of the modified reinforced polypropylene filter plate of high-content roving glass fiber |
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| CN110480973A true CN110480973A (en) | 2019-11-22 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109224630A (en) * | 2018-09-19 | 2019-01-18 | 中原工学院 | Assorted fibre net fibric reinforced polypropylene composite filter plate and preparation method thereof |
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| CN109224630A (en) * | 2018-09-19 | 2019-01-18 | 中原工学院 | Assorted fibre net fibric reinforced polypropylene composite filter plate and preparation method thereof |
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Application publication date: 20191122 |