CN111455723A - Method for accurately controlling product density in production process of aramid paper honeycomb - Google Patents
Method for accurately controlling product density in production process of aramid paper honeycomb Download PDFInfo
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- CN111455723A CN111455723A CN202010267587.8A CN202010267587A CN111455723A CN 111455723 A CN111455723 A CN 111455723A CN 202010267587 A CN202010267587 A CN 202010267587A CN 111455723 A CN111455723 A CN 111455723A
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
- D21H23/22—Addition to the formed paper
- D21H23/32—Addition to the formed paper by contacting paper with an excess of material, e.g. from a reservoir or in a manner necessitating removal of applied excess material from the paper
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/78—Controlling or regulating not limited to any particular process or apparatus
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H25/00—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00
- D21H25/04—Physical treatment, e.g. heating, irradiating
- D21H25/06—Physical treatment, e.g. heating, irradiating of impregnated or coated paper
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H25/00—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00
- D21H25/08—Rearranging applied substances, e.g. metering, smoothing; Removing excess material
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
- G01N9/02—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by measuring weight of a known volume
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
- G01N9/02—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by measuring weight of a known volume
- G01N2009/022—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by measuring weight of a known volume of solids
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Abstract
The invention discloses a method for accurately controlling product density in the production process of aramid paper honeycombs, belongs to the field of quality control of composite material products, and particularly relates to a method for accurately controlling product density in the production process; firstly testing the solid content of a dipped solution in a dipping process, and then calculating the gel hanging amount of the honeycomb by a formula; the honeycomb density is indirectly controlled by controlling the weight of the honeycomb in the process flow of the impregnation procedure. The invention utilizes the solid content of the dipped solution in the dipping process and accurately calculates the glue hanging amount of the honeycomb by a formula, thereby strictly controlling the density of the honeycomb and meeting the requirements of customers.
Description
Technical Field
The invention belongs to the field of quality control of composite material products, and particularly relates to a method for accurately controlling product density in a production process.
Background
The aramid paper honeycomb core material has a series of excellent performances such as light weight, high strength, high modulus, flame retardance and the like, and is widely applied to the fields of aerospace, high-speed trains and the like.
The gum dipping process is a very critical process in the manufacture of the aramid paper honeycomb, the process of dipping phenolic resin in the white honeycomb is completed in the process, the honeycomb reaches various required densities, the gum dipping process directly determines the density of the aramid paper honeycomb, and the performance of the honeycomb is further influenced.
At present, the common practice at home and abroad is to fix the specific gravity of the glue solution and obtain the glue hanging amount of the honeycomb according to experience, and once the specific gravity of the glue solution, the thickness of paper, the cells and the volume of the honeycomb are changed, the original experience parameters are changed, so that the density of the honeycomb is uncontrollable, the glue dipping is repeated, and the labor intensity of operators is increased.
Disclosure of Invention
The invention aims to provide a method for accurately controlling the product density in the production process of an aramid paper honeycomb, and aims to solve the technical problems that the honeycomb density is not controllable, repeated gum dipping occurs, and the labor intensity of an operator is increased.
In order to achieve the purpose, the specific technical scheme of the method for accurately controlling the product density in the production process of the aramid paper honeycomb is as follows:
a method for accurately controlling the product density in the production process of an aramid paper honeycomb comprises the steps of firstly testing the solid content of a dipped solution in a dipping process, and then calculating the glue hanging amount of the honeycomb through a formula;
the honeycomb density is indirectly controlled by controlling the weight of the honeycomb in the process flow of the gum dipping procedure, and the requirements of customers are met.
Further, the method comprises the following steps which are carried out in sequence:
step S1: detecting the solid content of the dipped solution;
step S2: measuring the volume and the weight of the honeycomb to be impregnated to obtain the weight of the impregnated honeycomb, namely the glue hanging amount;
step S3: placing the honeycomb to be subjected to whitening in the step S2 into a dipping tank for dipping, lifting the honeycomb at a certain speed after a period of time, and turning over glue flow;
when the weight reaches the glue hanging amount, stopping glue flowing, turning and uniformly distributing glue to enable the glue solution to be uniformly distributed in the honeycomb, and then entering the airing and curing process;
step S4: according to the formula of density
And calculating the density of the finished honeycomb.
Further, the step S1 specifically includes the following steps:
step S1-1: accurately weighing the measured glue solution by using an analytical balance;
step S1-2: putting the glue solution to be tested into an oven, and keeping the temperature for a period of time;
step S1-3: accurately weighing the constant-temperature glue solution to be measured;
step S1-4: calculating the solid content by formula 1;
wherein: w0Weighing the container by weight g
W1Weight g before constant temperature
W2The weight g after the temperature has been maintained.
Further, since the phenolic resin generates water during the curing reaction and evaporates, the oven temperature is set to 140-160 ℃ and the constant temperature time is 40-60min in the step S1-1.
Further, the step S2 specifically includes the following steps:
step S2-1: weighing the honeycomb to be whitened;
step S2-2: measuring the volume of the honeycomb to be whitened;
step S2-3: calculating the weight of the honeycomb after gum dipping, namely the hanging gum amount, by a formula 2:
wherein: g1Weight kg of honeycomb to be whitened
G2Weight kg of the honeycomb after impregnation
Rho- - - -density of the honeycomb kg/m3
V- -volume m of the honeycomb to be whitened3。
Further, the impregnated solution is phenolic resin.
The method for accurately controlling the product density in the production process of the aramid paper honeycomb has the following advantages: the method utilizes the solid content of the liquid to be dipped in the glue in the dipping process, and accurately calculates the glue hanging amount of the honeycomb by a formula, thereby strictly controlling the density of the honeycomb and being suitable for any glue solution concentration, paper thickness, cell and honeycomb volume. And simultaneously, the labor intensity of an operator is reduced.
Drawings
Fig. 1 is a process flow diagram of a gum dipping process of the method for accurately controlling the product density in the production process of the aramid paper honeycomb.
Detailed Description
In order to better understand the purpose, structure and function of the invention, the method for accurately controlling the product density in the production process of the aramid paper honeycomb of the invention is further described in detail with reference to the attached drawings.
As shown in figure 1, the solid content of the impregnated liquid is utilized in the impregnation process, and the gel hanging amount of the honeycomb is accurately calculated through a scientific formula, so that the density of the honeycomb can be strictly controlled, and the method is suitable for any glue solution concentration, paper thickness, cell and honeycomb volume.
Example 1:
producing 2.75 meshes with the density of 48kg/m3The thickness of the aramid paper honeycomb is 0.05 mm;
1. detecting the solid content of phenolic resin
1) Weighing the evaporating dish with an analytical balance0Is 149.2586g
2) Pouring phenolic resin to be measured into an evaporating dish, and weighing W1Is 152.949g
3) Placing the evaporating dish in oven with constant temperature of 140 deg.C, maintaining the temperature for 60min, taking out, placing in drier, and cooling to room temperature
4) The evaporating dish cooled to room temperature is weighed W2Is 150.7540g
5) And (3) calculating: substituting the data into formula 1 to obtain
The solid content of the phenolic resin is 40.5 percent
2. Weighing the honeycomb to be soaked by an electronic scale1Is 36.8kg
The length, width and height of the honeycomb to be whitened are measured by a measuring tape to be 2.56m, 1.35m and 0.46m respectively, and the volume V is calculated to be 1.59m3。
3. Substituting the data into formula 2 to obtain
G2＝134.4kg
4. Fixing the honeycomb to be soaked with the white clay by using a specific soaking frame, and then soaking the honeycomb in a soaking tank.
5. After soaking for 60min, lifting the honeycomb out of the glue liquid level at a constant speed, turning and flowing the glue, observing the electronic hanging scale degree of a specific glue dipping frame, stopping flowing the glue when the degree is close to 134.4kg, turning and uniformly gluing, taking the honeycomb out of the glue dipping frame when the glue is not easy to flow and glue lines are observed to be consistent, and placing the honeycomb in an airing place for airing.
6. Placing the aired honeycomb into a special honeycomb curing box, curing at the constant temperature of 155 ℃ for 90min, cooling to room temperature, taking out the honeycomb, measuring and weighing, wherein the measured length, width and height of the honeycomb are respectively 2.51m, 1.36m and 0.46m (the volume of the honeycomb is slightly changed after curing), weighing the honeycomb to obtain the weight of 74.8kg, and calculating the density of the finished honeycomb to be 47.6kg/m according to a density formula3Completely meet the standard of 48 +/-10 percent.
Example 2:
producing 1.83 cells with a density of 64kg/m3The thickness of the aramid paper honeycomb is 0.05 mm;
1. detecting the solid content of phenolic resin
1) Weighing the evaporating dish with an analytical balance0Is 149.2115g
2) Pouring phenolic resin to be measured into an evaporating dish, and weighing W1Is 155.8906g
3) Placing the evaporating dish in oven with constant temperature of 155 deg.C, maintaining the constant temperature for 45min, taking out, placing in drier, cooling to room temperature
4) The evaporating dish cooled to room temperature is weighed W2Is 151.9843g
5) And (3) calculating: substituting the data into formula 1 to obtain
The solid content of the phenolic resin is 41.5 percent
2. Weighing the honeycomb to be soaked by an electronic scale161.6 kg.
The length, width and height of the honeycomb to be whitened are measured by a measuring tape to be 2.75m, 1.40m and 0.475m respectively, and the volume V is calculated to be 1.83m3。
3. Substituting the data into formula 2 to obtain
G2＝195.4kg
4. Fixing the honeycomb to be soaked with the white clay by using a specific soaking frame, and then soaking the honeycomb in a soaking tank.
5. After soaking for 60min, lifting the honeycomb out of the glue liquid level at a constant speed, turning and flowing glue, observing the electronic hanging scale degree of a specific glue dipping frame, stopping flowing glue when the degree is close to 195.4kg, turning and uniformly gluing, taking the honeycomb out of the glue dipping frame when glue is not easy to flow and glue lines are observed to be consistent, and placing the honeycomb in an airing place for airing.
6. Placing the aired honeycomb into a special honeycomb curing box, curing at the constant temperature of 155 ℃ for 120min, cooling to room temperature, taking out the honeycomb, measuring and weighing, wherein the measured length, width and height of the honeycomb are respectively 2.615m, 1.343m and 0.475m (the volume of the honeycomb is slightly changed after curing), the weighed weight is 108.2kg, and the density of the finished honeycomb is calculated to be 64.9kg/m according to a density formula3Completely meet the standard of 64 +/-10 percent.
Example 3:
producing aramid paper honeycombs with 1.83-cell and 40kg/m3 density, wherein the paper thickness is 0.04 mm;
1. detecting the solid content of phenolic resin
1) Weighing the evaporating dish with an analytical balance0Is 149.1358g
2) Pouring phenolic resin to be measured into an evaporating dish, and weighing W1Is 153.3993g
3) Placing the evaporating dish into a drying oven with constant temperature of 160 deg.C, keeping the temperature for 40min, taking out, placing into a drier, and cooling to room temperature
4) The evaporating dish cooled to room temperature is weighed W2Is 150.2017g
5) And (3) calculating: substituting the data into formula 1 to obtain
The solid content of the phenolic resin is 25 percent
2. Weighing the honeycomb to be soaked by an electronic scale146.9 kg.
The length, width and height of the honeycomb to be whitened are measured by a measuring tape to be 2.795m, 1.373m and 0.440m respectively, and the volume V is calculated to be 1.69m3。
3. Substituting the data into formula 2 to obtain
G2＝129.7kg
4. Fixing the honeycomb to be soaked with the white clay by using a specific soaking frame, and then soaking the honeycomb in a soaking tank.
5. After soaking for 60min, lifting the honeycomb out of the glue liquid level at a constant speed, turning and flowing the glue, observing the electronic hanging scale degree of a specific glue dipping frame, stopping flowing the glue when the degree is close to 129.7kg, turning and uniformly gluing, taking the honeycomb out of the glue dipping frame when the glue is not easy to flow and glue lines are observed to be consistent, and placing the honeycomb in an airing place for airing.
6. Placing the aired honeycomb into a special honeycomb curing box, curing at the constant temperature of 155 ℃ for 90min, cooling to room temperature, taking out the honeycomb, measuring and weighing, wherein the measured length, width and height of the honeycomb are 2.730m, 1.372m and 0.440m respectively (the volume of the honeycomb is slightly changed after curing), the weighed weight is 65kg, and the density of the finished honeycomb is 39.4kg/m calculated according to a density formula3Completely meet the standard of 40 +/-10%.
It is to be understood that the present invention has been described with reference to certain embodiments, and that various changes in the features and embodiments, or equivalent substitutions may be made therein by those skilled in the art without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (5)
1. A method for accurately controlling the product density in the production process of an aramid paper honeycomb is characterized in that in a dipping process, the solid content of a dipped solution is firstly tested, and then the glue hanging amount of the honeycomb is calculated through a formula; in the process flow of the gum dipping procedure, the density of the honeycomb is indirectly controlled by controlling the weight of the honeycomb;
the method specifically comprises the following steps which are sequentially carried out:
step S1: detecting the solid content of the dipped solution;
step S2: measuring the volume and the weight of the honeycomb to be impregnated to obtain the weight of the impregnated honeycomb, namely the glue hanging amount;
step S3: placing the honeycomb to be subjected to whitening in the step S2 into a dipping tank for dipping, lifting the honeycomb at a certain speed after a period of time, and turning over glue flow;
when the weight reaches the glue hanging amount, stopping glue flowing, turning and uniformly distributing glue to enable the glue solution to be uniformly distributed in the honeycomb, and then entering the airing and curing process;
step S4: according to the formula of density
And calculating the density of the finished honeycomb.
2. The method for accurately controlling the product density in the aramid paper honeycomb production process according to claim 1, wherein the step S1 specifically comprises the following steps:
step S1-1: accurately weighing the measured glue solution by using an analytical balance;
step S1-2: putting the glue solution to be tested into an oven, and keeping the temperature for a period of time;
step S1-3: accurately weighing the constant-temperature glue solution to be measured;
step S1-4: calculating the solid content by formula 1;
wherein: w0Weighing the container by weight g
W1Weight g before constant temperature
W2The weight g after the temperature has been maintained.
3. The method for accurately controlling the product density in the production process of the aramid paper honeycomb as claimed in claim 2, wherein in the step S1-1, the oven temperature is set to 140-160 ℃ and the constant temperature time is 40-60 min.
4. The method for accurately controlling the product density in the aramid paper honeycomb production process according to claim 1, wherein the step S2 specifically comprises the following steps:
step S2-1: weighing the honeycomb to be whitened;
step S2-2: measuring the volume of the honeycomb to be whitened;
step S2-3: calculating the weight of the honeycomb after gum dipping, namely the hanging gum amount, by a formula 2:
wherein: g1Weight kg of honeycomb to be whitened
G2Weight kg of the honeycomb after impregnation
Rho- - - -density of the honeycomb kg/m3
V- -volume m of the honeycomb to be whitened3。
5. The method for accurately controlling the product density in the production process of the aramid paper honeycomb according to claim 3, wherein the impregnated solution is phenolic resin.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113290944A (en) * | 2021-05-31 | 2021-08-24 | 芜湖创联新材料科技有限公司 | Method for manufacturing aramid paper honeycomb with uniform density |
| CN114193903A (en) * | 2021-12-07 | 2022-03-18 | 北京卫星制造厂有限公司 | Sizing method for honeycomb core material of spacecraft |
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| CN110884226A (en) * | 2019-12-09 | 2020-03-17 | 中航复合材料有限责任公司 | Preparation method of multi-order density paper honeycomb core material |
| CN110940609A (en) * | 2019-10-31 | 2020-03-31 | 江南工业集团有限公司 | Method for measuring gum content of gum-dipped cloth |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113290944A (en) * | 2021-05-31 | 2021-08-24 | 芜湖创联新材料科技有限公司 | Method for manufacturing aramid paper honeycomb with uniform density |
| CN114193903A (en) * | 2021-12-07 | 2022-03-18 | 北京卫星制造厂有限公司 | Sizing method for honeycomb core material of spacecraft |
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