WO2023039932A1 - Method for calculating diameter reduction amount of fluorosilicone-modified pert barrier liner pipe by using finite element algorithm - Google Patents

Method for calculating diameter reduction amount of fluorosilicone-modified pert barrier liner pipe by using finite element algorithm Download PDF

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WO2023039932A1
WO2023039932A1 PCT/CN2021/120678 CN2021120678W WO2023039932A1 WO 2023039932 A1 WO2023039932 A1 WO 2023039932A1 CN 2021120678 W CN2021120678 W CN 2021120678W WO 2023039932 A1 WO2023039932 A1 WO 2023039932A1
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pert
diameter reduction
layer
pipe
finite element
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褚展鹏
金崇阳
刘跃明
霍福磊
陈江慧
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临海伟星新型建材有限公司
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    • G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
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    • G06F2113/00—Details relating to the application field
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    • G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces

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  • the invention belongs to the technical field of diameter reduction calculation of lining pipes, and in particular relates to a calculation method for diameter reduction calculation of fluorine-silicon modified PERT barrier lining pipes using a finite element algorithm.
  • Fluorosilicone modified PERT barrier lining pipe is used as a multi-layer pipe.
  • the pipe material and size of each layer of pipe are different, and the required diameter reduction is also different.
  • a suitable diameter reduction for one layer cannot be selected arbitrarily.
  • diameter reduction it is necessary to select a unified diameter reduction amount for multi-layer pipes.
  • the object of the present invention is to provide a method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm.
  • a method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm includes the following steps:
  • step 1) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply the corresponding uniform external pressure of P min to the whole pipe, and run the calculation to obtain the shrinkage of the overall liner pipe.
  • P C is the buckling critical external pressure
  • P eL is the elastic term of the buckling pressure, which is calculated from the Young's modulus of E integral lining pipe, t wall thickness, D outer diameter and v Poisson's ratio
  • P p is the buckling
  • the plastic item of pressure where SMYS is the characteristic yield strength, and f 0 is the out-of-roundness of the pipe, after calculating the elastic item and plastic item of the yield pressure, it is substituted into the solution and combined to obtain the respective PC values of each layer;
  • step 1) model in the finite element software, and substitute the material parameters of each layer, apply a uniform external pressure of P C to the whole pipe, and run the calculation to obtain the diameter reduction of the overall lining pipe
  • L max of the value The upper limit L max of the value
  • the functional inner layer includes the following components: 50-60 parts by weight of PERT II pellets, 30-40 parts of PE pellets, 10-15 parts of fluorine-containing monomers, 330 parts of antioxidant 0.5-1 part, 0.15 part of initiator, 0.075 part of calcium carbonate.
  • ⁇ is the principal stress
  • ⁇ is the shear stress
  • ⁇ and ⁇ are the strains.
  • the distribution of ⁇ r is integrally calculated in the thickness direction to obtain the overall deformation in the radial direction, that is, the diameter reduction L min and L max .
  • D is the outer diameter and d is the inner diameter.
  • the value range of D is 50mm-315mm, and the value range of t is 0.05D-0.15D.
  • f 0 in step 5 ⁇ 0.5%.
  • the invention has the beneficial effects of providing a theoretical calculation method for the fluorine-silicon modified PERT barrier liner, reducing unnecessary experiments, reducing operational errors, and improving work efficiency.
  • Fig. 1 is the structural representation of the fluorosilicon modified PERT barrier liner of the present invention
  • Fig. 2 is a calculation flow chart of the present invention.
  • a fluorine-silicon modified PERT barrier liner is shown in Figure 1. From the inside to the outside, it is the functional inner layer, the first hot melt adhesive layer 2, the barrier layer 3, the second hot melt adhesive layer 4 and the protective outer layer. 5.
  • Figure 2 represents the operation process of the diameter reduction calculation method: the minimum critical external pressure is obtained by calculating the minimum shear strength, and then the lower limit of the diameter reduction is obtained by finite element modeling calculation; the buckling critical external pressure is obtained by calculating the buckling instability criterion , and then perform finite element modeling calculations to obtain the upper limit of the diameter reduction value, and determine the final diameter reduction value through the upper and lower limits.
  • the functional inner layer 1 includes the following components: 55 parts by weight of PERT II pellets, 30 parts of PE pellets, and 10 parts of fluorine-containing monomers , 3301 parts of antioxidant, 0.15 part of initiator, and 0.075 part of calcium carbonate; the outer diameter of the prepared fluorosilicon modified PERT barrier liner is 110mm, and the thickness is 10mm.
  • the material performance test of the whole pipe section has a density of 0.958 g/cm 3 , the overall equivalent Young's modulus E is 996MPa, Poisson's ratio v is 0.35, and the tensile yield strength is 25MPa.
  • step 1) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer (as shown in Table 1), corresponding to the uniform external pressure of P min , run the calculation to obtain the overall lining
  • Hot melt adhesive layer 435 0.5 31.7 protective outer layer 920 0.3 twenty two
  • P C is the buckling critical external pressure
  • P eL is the elastic term of the buckling pressure, which is calculated from the overall equivalent Young's modulus of E, the wall thickness of t, the outer diameter of D and Poisson's ratio of v
  • P p is the buckling pressure
  • SMYS the characteristic yield strength
  • step 1) model in the finite element software, and substitute the material parameters of each layer, apply the uniform external pressure of PC , and run the calculation to obtain the value of the diameter reduction of the overall liner.
  • Upper limit L max 6.53mm;
  • the functional inner layer 1 includes the following components: 55 parts by weight of PERT II pellets, 30 parts of PE pellets, and 10 parts of fluorine-containing monomers , 3301 parts of antioxidant, 0.15 parts of initiator, and 0.075 parts of calcium carbonate; the outer diameter of the prepared fluorosilicon modified PERT barrier liner is 250mm, and the thickness is 22.7mm. 0.958g/cm 3 , the overall equivalent Young's modulus E is 996MPa, Poisson's ratio v is 0.35, and the tensile yield strength is 25MPa.
  • step 1) Based on the geometric dimension parameters obtained in step 1), model in the finite element software, and substitute into the material parameters of each layer (as shown in Table 2), corresponding to the uniform external pressure of P min , run the calculation to obtain the overall lining
  • the lower limit of the diameter reduction value of the pipe L min 1.86mm;
  • P C is the buckling critical external pressure
  • P eL is the elastic term of the buckling pressure, which is calculated from the overall equivalent Young's modulus of E, the wall thickness of t, the outer diameter of D and Poisson's ratio of v
  • step 1) model in the finite element software, and substitute the material parameters of each layer, apply the uniform external pressure of PC , and run the calculation to obtain the value of the diameter reduction of the overall liner.
  • the upper limit L max 8.93mm.
  • the material ratio for preparing the fluorine-silicon modified PERT barrier liner is 50-60 parts by weight of PERT II type pellets, 30-40 parts of PE pellets, and 10-15 parts of fluorine-containing monomers.

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Abstract

Disclosed in the present invention is a method for calculating the diameter reduction amount of a fluorosilicone-modified PERT barrier liner pipe by using a finite element algorithm. The fluorosilicone-modified PERT barrier liner pipe comprises a protective outer layer, a second hot-melt adhesive layer, a barrier layer, a first hot-melt adhesive layer and a functional inner layer. The method comprises the following steps: determining, by means of testing, necessary parameters which correspond to each layer and to the whole liner pipe; obtaining, by means of calculation, the minimum critical external pressure of the whole liner pipe; performing modeling in finite element software, applying the minimum critical external pressure, and obtaining, by means of calculation, a lower limit for the diameter reduction amount of the whole liner pipe; obtaining, by means of calculation, a critical buckling external pressure of the whole liner pipe; performing modeling in the finite element software, applying the critical buckling external pressure, and obtaining, by means of calculation, an upper limit for the overall diameter reduction amount; and taking a value from the range interval of the upper limit and the lower limit, and using same as the diameter reduction amount of a fluorosilicone-modified PERT barrier liner pipe. The present invention provides a theoretical calculation method for the diameter reduction amount of a fluorosilicone-modified PERT barrier liner pipe; and during an actual operation process, experiments are decreased and errors are reduced, thereby improving the efficiency.

Description

采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法Calculation method of diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm 技术领域technical field
本发明属于内衬管缩径量计算的技术领域，具体涉及采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法。The invention belongs to the technical field of diameter reduction calculation of lining pipes, and in particular relates to a calculation method for diameter reduction calculation of fluorine-silicon modified PERT barrier lining pipes using a finite element algorithm.
背景技术Background technique
氟硅改性PERT阻隔内衬管作为多层管，每一层管的管材和尺寸都不同，所需要的缩径量也不同，在实际操作过程中不能任意选择一个适合一层的缩径量进行缩径，因此需要对多层管进行一个统一的缩径量的选择。Fluorosilicone modified PERT barrier lining pipe is used as a multi-layer pipe. The pipe material and size of each layer of pipe are different, and the required diameter reduction is also different. In the actual operation process, a suitable diameter reduction for one layer cannot be selected arbitrarily. For diameter reduction, it is necessary to select a unified diameter reduction amount for multi-layer pipes.
在实际操作过程中，对于多层管可能会采取经验主义来取一个合适的缩径量进行缩径操作，缺少一套成熟的不同材料、不同温度、不同尺寸下的缩径量计算方法。In the actual operation process, for multi-layer pipes, it may be empirical to take a suitable diameter reduction for diameter reduction operation, and there is a lack of a set of mature calculation methods for diameter reduction under different materials, different temperatures, and different sizes.
发明内容Contents of the invention
为解决上述问题，本发明的目的在于提供一种采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法。In order to solve the above problems, the object of the present invention is to provide a method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm.
为达到上述目的，提出以下技术方案：In order to achieve the above object, the following technical solutions are proposed:
采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，所述氟硅改性PERT阻隔内衬管包括功能内层、第一热熔胶层、阻隔层、第二热熔胶层和保护外层，所述功能内层的材质为氟硅改性的PERT；阻隔层的材质为EVOH；所述保护外层的材质为保护外层材质为PERT，计算方法包括如下步骤：A method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm. The adhesive layer and the protective outer layer, the material of the functional inner layer is PERT modified by fluorosilicon; the material of the barrier layer is EVOH; the material of the protective outer layer is PERT, and the calculation method includes the following steps:
1)测量确定功能内层、第一热熔胶层、阻隔层、第二热熔胶层和保护外层相应的必要参数，对制备得到的整体管进行力学性能测试，得到相应的整体内衬管参数；1) Measure and determine the corresponding necessary parameters of the functional inner layer, the first hot-melt adhesive layer, the barrier layer, the second hot-melt adhesive layer and the protective outer layer, and test the mechanical properties of the prepared integral pipe to obtain the corresponding integral inner lining Pipe parameters;
2)确定氟硅改性PERT阻隔内衬管与钢管剪切强度的最小剪切强度τ min： 2) Determine the minimum shear strength τ min of the shear strength of fluorine-silicon modified PERT barrier liner and steel pipe:
3)计算整体内衬管的最小临界外压P min：根据内衬管与钢管摩擦系数f，计算最小临界外压P min＝τ min/f； 3) Calculate the minimum critical external pressure P min of the overall lined pipe: according to the friction coefficient f between the lined pipe and the steel pipe, calculate the minimum critical external pressure P min =τ min /f;
4)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数，对管材整体施加对应的P min的均匀外压，运行计算得到整体内衬管的缩径量取值的下限L min； 4) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply the corresponding uniform external pressure of P min to the whole pipe, and run the calculation to obtain the shrinkage of the overall liner pipe. The lower limit L min of diameter measurement;
5)计算每一层的屈曲临界外压Pc：将步骤1)所得的材料参数分别代入屈曲临界外压的计算公式，具体如下：5) Calculate the buckling critical external pressure Pc of each layer: Substitute the material parameters obtained in step 1) into the calculation formula of the buckling critical external pressure, as follows:
Figure PCTCN2021120678-appb-000001
Figure PCTCN2021120678-appb-000001
其中
Figure PCTCN2021120678-appb-000002
P C即为屈曲临界外压，P eL为屈曲压力的弹性项，其由E整体内衬管的杨氏模量、t壁厚、D外径和v泊松比计算得，P p为屈曲压力的塑性项，其中SMYS为特征屈服强度，f 0为管材的不圆度，在计算完屈服压力的弹性项和塑性项之后代入求解结合得到各层各自的P C的数值； in
Figure PCTCN2021120678-appb-000002
P C is the buckling critical external pressure, P eL is the elastic term of the buckling pressure, which is calculated from the Young's modulus of E integral lining pipe, t wall thickness, D outer diameter and v Poisson's ratio, P p is the buckling The plastic item of pressure, where SMYS is the characteristic yield strength, and f 0 is the out-of-roundness of the pipe, after calculating the elastic item and plastic item of the yield pressure, it is substituted into the solution and combined to obtain the respective PC values of each layer;
6)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数，对管材整体施加P C的均匀外压，运行计算得到整体内衬管的缩径量取值的上限L max； 6) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply a uniform external pressure of P C to the whole pipe, and run the calculation to obtain the diameter reduction of the overall lining pipe The upper limit L max of the value;
7)根据步骤4)和6)得到的L min和L max，依据实际的工程取L max和L min的范围区间内取值作为氟硅改性PERT阻隔内衬管缩径量。 7) According to the L min and L max obtained in steps 4) and 6), the value within the range of L max and L min is taken as the diameter reduction of the fluorosilicon modified PERT barrier liner according to the actual project.
进一步地，所述的功能内层包含如下组分：按重量份计为PERT Ⅱ型粒料50-60份、PE粒料30-40份、含氟单体10-15份、抗氧剂330 0.5-1份、引发剂0.15份、碳酸钙0.075份。Further, the functional inner layer includes the following components: 50-60 parts by weight of PERT II pellets, 30-40 parts of PE pellets, 10-15 parts of fluorine-containing monomers, 330 parts of antioxidant 0.5-1 part, 0.15 part of initiator, 0.075 part of calcium carbonate.
进一步地，有限元软件中建模为联立三大基本方程求解：Furthermore, the modeling in the finite element software is to solve the three basic equations simultaneously:
1)平衡方程1) Balance equation
Figure PCTCN2021120678-appb-000003
Figure PCTCN2021120678-appb-000003
Figure PCTCN2021120678-appb-000004
Figure PCTCN2021120678-appb-000004
式中f表示摩擦力；where f is the friction force;
2)物理方程(应力与应变的关系)2) Physical equation (relationship between stress and strain)
Figure PCTCN2021120678-appb-000005
Figure PCTCN2021120678-appb-000005
Figure PCTCN2021120678-appb-000006
Figure PCTCN2021120678-appb-000006
Figure PCTCN2021120678-appb-000007
Figure PCTCN2021120678-appb-000007
式中E为杨氏模量，v为泊松比；Where E is Young's modulus, v is Poisson's ratio;
3)变形协调方程(位移与应变的关系)3) Deformation coordination equation (relationship between displacement and strain)
Figure PCTCN2021120678-appb-000008
Figure PCTCN2021120678-appb-000008
式中σ为主应力，τ为切应力，ε和γ为应变。In the formula, σ is the principal stress, τ is the shear stress, ε and γ are the strains.
进一步地，应力分量和应变分量与角度θ无关，σ r＝P，将步骤3)和步骤5)得到的P min和P C依次代入以上所有方程中联立求解，求解得到对应的径向应变ε r的分布，进行厚度方向的积分计算，即得到径 向整体变形量，即缩径量L min和L max。 Furthermore, the stress component and the strain component have nothing to do with the angle θ, σ r =P, the P min and P C obtained in step 3) and step 5) are substituted into all the above equations and solved simultaneously, and the corresponding radial strain is obtained by solving The distribution of ε r is integrally calculated in the thickness direction to obtain the overall deformation in the radial direction, that is, the diameter reduction L min and L max .
进一步地，厚度方向的积分计算式为Further, the integral calculation formula in the thickness direction is
Figure PCTCN2021120678-appb-000009
Figure PCTCN2021120678-appb-000009
其中D为外径，d为内径。Where D is the outer diameter and d is the inner diameter.
进一步地，最小剪切强度τ min≥0.15MPa。 Further, the minimum shear strength τ min ≥ 0.15MPa.
进一步地，D的取值范围为50mm-315mm，t的取值范围为0.05D-0.15D。Further, the value range of D is 50mm-315mm, and the value range of t is 0.05D-0.15D.
进一步地，步骤5)中的f 0≥0.5％。 Further, f 0 in step 5) ≥ 0.5%.
本发明的有益效果在于：为氟硅改性PERT阻隔内衬管提供理论计算方法，减少不必要的实验，减少操作误差，提高工作效率。The invention has the beneficial effects of providing a theoretical calculation method for the fluorine-silicon modified PERT barrier liner, reducing unnecessary experiments, reducing operational errors, and improving work efficiency.
附图说明Description of drawings
图1为本发明的氟硅改性PERT阻隔内衬管的结构示意图；Fig. 1 is the structural representation of the fluorosilicon modified PERT barrier liner of the present invention;
图2为本发明的计算流程图。Fig. 2 is a calculation flow chart of the present invention.
图中：1、功能内层；2、第一热熔胶层；3、阻隔层；4、第二热熔胶层；5、保护外层。In the figure: 1. Functional inner layer; 2. First hot melt adhesive layer; 3. Barrier layer; 4. Second hot melt adhesive layer; 5. Protective outer layer.
具体实施方式Detailed ways
下面结合说明书附图和实施例对本发明做进一步地说明，但本发明的保护范围并不仅限于此。The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but the protection scope of the present invention is not limited thereto.
一种氟硅改性PERT阻隔内衬管如图1所示，从内到外依次为功能内层、第一热熔胶层2、阻隔层3、第二热熔胶层4和保护外层5。A fluorine-silicon modified PERT barrier liner is shown in Figure 1. From the inside to the outside, it is the functional inner layer, the first hot melt adhesive layer 2, the barrier layer 3, the second hot melt adhesive layer 4 and the protective outer layer. 5.
图2代表缩径量计算方法的操作过程：通过最小剪切强度计算得到最小临界外压，然后进行有限元建模计算得到缩径量取值下限；通 过屈曲失稳准则计算得到屈曲临界外压，然后进行有限元建模计算得到缩径量取值的上限，通过上限和下限确定最终缩径量的值。Figure 2 represents the operation process of the diameter reduction calculation method: the minimum critical external pressure is obtained by calculating the minimum shear strength, and then the lower limit of the diameter reduction is obtained by finite element modeling calculation; the buckling critical external pressure is obtained by calculating the buckling instability criterion , and then perform finite element modeling calculations to obtain the upper limit of the diameter reduction value, and determine the final diameter reduction value through the upper and lower limits.
实施例1Example 1
1)制备氟硅改性PERT阻隔内衬管：所述的功能内层1包含如下组分：按重量份计为PERT Ⅱ型粒料55份、PE粒料30份、含氟单体10份、抗氧剂3301份、引发剂0.15份、碳酸钙0.075份；制备得到的氟硅改性PERT阻隔内衬管的外径为110mm，厚度为10mm，对整体管段进行材料性能测试，密度为0.958g/cm 3，整体等效杨氏模量E为996MPa，泊松比v为0.35，拉伸屈服强度为25MPa，
Figure PCTCN2021120678-appb-000010
Figure PCTCN2021120678-appb-000011
实际生产中该系列管子容许公差为+0.7mm，故计算得到f 0＝0.64％，又由于公式要求f 0≥0.5％，故此时f 0取0.64％，SMYS＝25*0.8＝20MPa。 1) Preparation of fluorine-silicon modified PERT barrier liner: the functional inner layer 1 includes the following components: 55 parts by weight of PERT II pellets, 30 parts of PE pellets, and 10 parts of fluorine-containing monomers , 3301 parts of antioxidant, 0.15 part of initiator, and 0.075 part of calcium carbonate; the outer diameter of the prepared fluorosilicon modified PERT barrier liner is 110mm, and the thickness is 10mm. The material performance test of the whole pipe section has a density of 0.958 g/cm 3 , the overall equivalent Young's modulus E is 996MPa, Poisson's ratio v is 0.35, and the tensile yield strength is 25MPa.
Figure PCTCN2021120678-appb-000010
Figure PCTCN2021120678-appb-000011
In actual production, the allowable tolerance of this series of pipes is +0.7mm, so the calculated f 0 =0.64%, and because the formula requires f 0 ≥0.5%, so at this time f 0 is taken as 0.64%, SMYS=25*0.8=20MPa.
2)确定氟硅改性PERT阻隔内衬管外层与钢管剪切强度的最小剪切强度τ min，最小剪切强度需要大于0.15Mpa。 2) Determine the minimum shear strength τ min between the outer layer of the fluorine-silicon modified PERT barrier liner and the steel pipe, and the minimum shear strength must be greater than 0.15Mpa.
3)计算整体内衬管的最小临界外压P min：根据内衬管与钢管摩擦系数f＝0.25，计算最小临界外压P min＝τ min/f＝0.6MPa； 3) Calculate the minimum critical external pressure P min of the overall lined pipe: according to the friction coefficient f=0.25 between the lined pipe and the steel pipe, calculate the minimum critical external pressure P min =τ min /f=0.6MPa;
4)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数(如表1所示)，对应施加P min的均匀外压，运行计算得到整体内衬管的缩径量取值的下限L min＝1.08mm。 4) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer (as shown in Table 1), corresponding to the uniform external pressure of P min , run the calculation to obtain the overall lining The lower limit of the diameter reduction of the pipe is L min =1.08mm.
表1实施例1制备得到的氟硅改性PERT阻隔内衬管相应参数Table 1 Corresponding parameters of the fluorosilicon modified PERT barrier liner prepared in Example 1
各层材料Material of each layer 杨氏模量(MPa)Young's modulus (MPa) 泊松比Poisson's ratio 拉伸强度(MPa)Tensile strength (MPa)
功能内层Functional inner layer 10201020 0.360.36 2525
阻隔层barrier layer 22532253 0.10.1 13.613.6
热熔胶层Hot melt adhesive layer 435435 0.50.5 31.731.7
保护外层protective outer layer 920920 0.30.3 22twenty two
5)计算整体内衬管的屈曲临界外压Pc：将步骤1)所得的材料参数分别代入屈曲临界外压的计算公式，具体如下：5) Calculation of the buckling critical external pressure Pc of the integrally lined pipe: Substitute the material parameters obtained in step 1) into the calculation formula of the buckling critical external pressure, as follows:
Figure PCTCN2021120678-appb-000012
Figure PCTCN2021120678-appb-000012
其中
Figure PCTCN2021120678-appb-000013
P C即为屈曲临界外压，P eL为屈曲压力的弹性项，其由E整体等效杨氏模量、t的壁厚、D外径和v泊松比计算得，P p为屈曲压力的塑性项，其中SMYS为特征屈服强度，f 0为每一层管材的不圆度，在计算完屈服压力的弹性项和塑性项之后代入求解结合得到管段整体的P C的数值，P eL＝0.819MPa，P p＝6.83MPa，求解三次方程组得到屈曲临界外压P C＝2.25MPa； in
Figure PCTCN2021120678-appb-000013
P C is the buckling critical external pressure, P eL is the elastic term of the buckling pressure, which is calculated from the overall equivalent Young's modulus of E, the wall thickness of t, the outer diameter of D and Poisson's ratio of v, and P p is the buckling pressure where SMYS is the characteristic yield strength, and f 0 is the out-of-roundness of each layer of pipe, after calculating the elastic and plastic terms of the yield pressure, it is substituted into the solution and combined to obtain the value of P C of the whole pipe section, P eL = 0.819MPa, P p ＝6.83MPa, solve the cubic equations to get the buckling critical external pressure P C ＝2.25MPa;
6)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数，施加P C的均匀外压，运行计算得到整体内衬管的缩径量取值的上限L max＝6.53mm； 6) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply the uniform external pressure of PC , and run the calculation to obtain the value of the diameter reduction of the overall liner. Upper limit L max =6.53mm;
7)根据步骤4)和6)得到的L min和L max，并在最小的L max和最大的L min的范围区间内取值作为氟硅改性PERT阻隔内衬管缩径量，缩径量的取值范围为[1.08mm,6.53mm],根据线性差值可取缩径量为3.8mm。 7) According to the L min and L max obtained in steps 4) and 6), take a value within the range of the minimum L max and the maximum L min as the diameter reduction of the fluorosilicon modified PERT barrier liner, the diameter reduction The value range of the amount is [1.08mm, 6.53mm], according to the linear difference, the diameter reduction amount can be 3.8mm.
实施例2Example 2
1)制备氟硅改性PERT阻隔内衬管：所述的功能内层1包含如下 组分：按重量份计为PERT Ⅱ型粒料55份、PE粒料30份、含氟单体10份、抗氧剂3301份、引发剂0.15份、碳酸钙0.075份；制备得到的氟硅改性PERT阻隔内衬管的外径为250mm，厚度为22.7mm，对整体管段进行材料性能测试，密度为0.958g/cm 3，整体等效杨氏模量E为996MPa，泊松比v为0.35，拉伸屈服强度为25MPa，
Figure PCTCN2021120678-appb-000014
实际生产中该系列管子容许公差为+0.7mm，故计算得到f 0＝0.64％，又由于公式要求f 0≥0.5％，故此时f 0取0.64％，SMYS＝25*0.8＝20MPa； 1) Preparation of fluorine-silicon modified PERT barrier liner: the functional inner layer 1 includes the following components: 55 parts by weight of PERT II pellets, 30 parts of PE pellets, and 10 parts of fluorine-containing monomers , 3301 parts of antioxidant, 0.15 parts of initiator, and 0.075 parts of calcium carbonate; the outer diameter of the prepared fluorosilicon modified PERT barrier liner is 250mm, and the thickness is 22.7mm. 0.958g/cm 3 , the overall equivalent Young's modulus E is 996MPa, Poisson's ratio v is 0.35, and the tensile yield strength is 25MPa.
Figure PCTCN2021120678-appb-000014
In actual production, the allowable tolerance of this series of pipes is +0.7mm, so the calculated f 0 =0.64%, and because the formula requires f 0 ≥0.5%, so at this time f 0 is taken as 0.64%, SMYS=25*0.8=20MPa;
2)确定氟硅改性PERT阻隔内衬管外层与钢管剪切强度的最小剪切强度τ min，最小剪切强度需要大于0.15Mpa； 2) Determine the minimum shear strength τ min between the outer layer of the fluorine-silicon modified PERT barrier liner and the steel pipe, and the minimum shear strength must be greater than 0.15Mpa;
3)计算整体内衬管的最小临界外压P min：根据内衬管与钢管摩擦系数f＝0.25，计算最小临界外压P min＝τ min/f＝0.6MPa； 3) Calculate the minimum critical external pressure P min of the overall lined pipe: according to the friction coefficient f=0.25 between the lined pipe and the steel pipe, calculate the minimum critical external pressure P min =τ min /f=0.6MPa;
4)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数(如表2所示)，对应施加P min的均匀外压，运行计算得到整体内衬管的缩径量取值的下限L min＝1.86mm； 4) Based on the geometric dimension parameters obtained in step 1), model in the finite element software, and substitute into the material parameters of each layer (as shown in Table 2), corresponding to the uniform external pressure of P min , run the calculation to obtain the overall lining The lower limit of the diameter reduction value of the pipe L min = 1.86mm;
表2实施例2制备得到的氟硅改性PERT阻隔内衬管相应参数Table 2 Corresponding parameters of the fluorosilicon modified PERT barrier liner prepared in Example 2
各层材料Material of each layer 杨氏模量(MPa)Young's modulus (MPa) 泊松比Poisson's ratio 拉伸强度(MPa)Tensile strength (MPa)
功能内层Functional inner layer 10201020 0.360.36 2525
阻隔层barrier layer 22532253 0.10.1 13.613.6
热熔胶层Hot melt adhesive layer 435435 0.50.5 31.731.7
保护外层protective outer layer 920920 0.30.3 22twenty two
5)计算整体内衬管的屈曲临界外压Pc：将步骤1)所得的材料 参数分别代入屈曲临界外压的计算公式，具体如下：5) Calculate the buckling critical external pressure Pc of the integrally lined pipe: Substitute the material parameters obtained in step 1) into the calculation formula of the buckling critical external pressure, as follows:
Figure PCTCN2021120678-appb-000015
Figure PCTCN2021120678-appb-000015
其中
Figure PCTCN2021120678-appb-000016
P C即为屈曲临界外压，P eL为屈曲压力的弹性项，其由E整体等效杨氏模量、t的壁厚、D外径和v泊松比计算得，P p为屈曲压力的塑性项，其中SMYS为特征屈服强度，f 0为每一层管材的不圆度，在计算完屈服压力的弹性项和塑性项之后代入求解结合得到管段整体的P C的数值，P eL＝1.965MPa，P p＝5.54MPa，求解三次方程组得到屈曲临界外压P C＝3.31MPa； in
Figure PCTCN2021120678-appb-000016
P C is the buckling critical external pressure, P eL is the elastic term of the buckling pressure, which is calculated from the overall equivalent Young's modulus of E, the wall thickness of t, the outer diameter of D and Poisson's ratio of v, and P p is the buckling pressure where SMYS is the characteristic yield strength, and f 0 is the out-of-roundness of each layer of pipe, after calculating the elastic and plastic terms of the yield pressure, it is substituted into the solution and combined to obtain the value of P C of the whole pipe section, P eL = 1.965MPa, P p ＝5.54MPa, solve the cubic equation to get the buckling critical external pressure P C ＝3.31MPa;
6)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数，施加P C的均匀外压，运行计算得到整体内衬管的缩径量取值的上限L max＝8.93mm。 6) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply the uniform external pressure of PC , and run the calculation to obtain the value of the diameter reduction of the overall liner. The upper limit L max =8.93mm.
7)根据步骤4)和6)得到的L min和L max，并在最小的L max和最大的L min的范围区间内取值作为氟硅改性PERT阻隔内衬管缩径量，缩径量的取值范围为[1.86mm,8.93mm]，缩径量取5.395mm。 7) According to the L min and L max obtained in steps 4) and 6), take a value within the range of the minimum L max and the maximum L min as the diameter reduction of the fluorosilicon modified PERT barrier liner, the diameter reduction The value range of the amount is [1.86mm, 8.93mm], and the diameter reduction is 5.395mm.
除上述实施例外，制备氟硅改性PERT阻隔内衬管的材料配比为按重量份计为PERT Ⅱ型粒料50-60份、PE粒料30-40份、含氟单体10-15份、抗氧剂330 0.5-1份、引发剂0.15份、碳酸钙0.075份；不同的材料制备得到的管材的整体等效杨氏模量和泊松比参数发生变化。In addition to the above-mentioned examples, the material ratio for preparing the fluorine-silicon modified PERT barrier liner is 50-60 parts by weight of PERT II type pellets, 30-40 parts of PE pellets, and 10-15 parts of fluorine-containing monomers. 0.5-1 part of antioxidant 330, 0.15 part of initiator, and 0.075 part of calcium carbonate; the overall equivalent Young's modulus and Poisson's ratio parameters of pipes prepared from different materials changed.

Claims (8)

  1. 采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，所述氟硅改性PERT阻隔内衬管包括功能内层(1)、第一热熔胶层(2)、阻隔层(3)、第二热熔胶层(4)和保护外层(5)，所述功能内层(1)的材质为氟硅改性的PERT；阻隔层(3)的材质为EVOH；所述保护外层(5)的材质为保护外层材质为PERT，计算方法包括如下步骤：The method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm is characterized in that the fluorine-silicon modified PERT barrier liner includes a functional inner layer (1), a first hot melt adhesive layer ( 2), the barrier layer (3), the second hot melt adhesive layer (4) and the protective outer layer (5), the material of the functional inner layer (1) is PERT modified by fluorosilicon; the barrier layer (3) The material is EVOH; the material of the protective outer layer (5) is PERT, and the calculation method includes the following steps:
    1)测量确定功能内层(1)、第一热熔胶层(2)、阻隔层(3)、第二热熔胶层(4)和保护外层(5)相应的必要参数，对制备得到的整体管进行力学性能测试，得到相应的整体内衬管参数；1) Measure and determine the necessary parameters corresponding to the functional inner layer (1), the first hot-melt adhesive layer (2), the barrier layer (3), the second hot-melt adhesive layer (4) and the protective outer layer (5). The obtained monolithic pipe is tested for mechanical properties, and the corresponding monolithic lining pipe parameters are obtained;
    2)确定氟硅改性PERT阻隔内衬管与钢管剪切强度的最小剪切强度τ min： 2) Determine the minimum shear strength τ min of the shear strength of fluorine-silicon modified PERT barrier liner and steel pipe:
    3)计算整体内衬管的最小临界外压P min：根据内衬管与钢管摩擦系数f，计算最小临界外压P min＝τ min/f； 3) Calculate the minimum critical external pressure P min of the overall lined pipe: according to the friction coefficient f between the lined pipe and the steel pipe, calculate the minimum critical external pressure P min =τ min /f;
    4)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数，对管材整体施加对应的P min的均匀外压，运行计算得到整体内衬管的缩径量取值的下限L min； 4) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply the corresponding uniform external pressure of P min to the whole pipe, and run the calculation to obtain the shrinkage of the overall liner pipe. The lower limit L min of diameter measurement;
    5)计算每一层的屈曲临界外压Pc：将步骤1)所得的材料参数分别代入屈曲临界外压的计算公式，具体如下：5) Calculate the buckling critical external pressure Pc of each layer: Substitute the material parameters obtained in step 1) into the calculation formula of the buckling critical external pressure, as follows:
    Figure PCTCN2021120678-appb-100001
    Figure PCTCN2021120678-appb-100001
    其中
    Figure PCTCN2021120678-appb-100002
    P C即为屈曲临界外压，P eL为屈曲 压力的弹性项，其由E整体内衬管的杨氏模量、t壁厚、D外径和v泊松比计算得，P p为屈曲压力的塑性项，其中SMYS为特征屈服强度，f 0为管材的不圆度，在计算完屈服压力的弹性项和塑性项之后代入求解结合得到P C的数值；     in
    Figure PCTCN2021120678-appb-100002
    P C is the buckling critical external pressure, P eL is the elastic term of the buckling pressure, which is calculated from the Young's modulus of E integral lining pipe, t wall thickness, D outer diameter and v Poisson's ratio, P p is the buckling The plastic item of pressure, where SMYS is the characteristic yield strength, and f 0 is the out-of-roundness of the pipe, after calculating the elastic item and plastic item of the yield pressure, it is substituted into the solution and combined to obtain the value of P C ;
    6)根据步骤1)得到的几何尺寸参数在有限元软件中建模，并代入每一层的材料参数，对管材整体施加P C的均匀外压，运行计算得到整体内衬管的缩径量取值的上限L max； 6) According to the geometric size parameters obtained in step 1), model in the finite element software, and substitute the material parameters of each layer, apply a uniform external pressure of P C to the whole pipe, and run the calculation to obtain the diameter reduction of the overall lining pipe The upper limit L max of the value;
    7)根据步骤4)和6)得到的L min和L max，依据实际的工程取L max和L min的范围区间内取值作为氟硅改性PERT阻隔内衬管缩径量。 7) According to the L min and L max obtained in steps 4) and 6), the value within the range of L max and L min is taken as the diameter reduction of the fluorosilicon modified PERT barrier liner according to the actual project.
  2. 如权利要求1所述的采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，所述的功能内层(1)包含如下组分：按重量份计为PERTⅡ型粒料50-60份、PE粒料30-40份、含氟单体10-15份、抗氧剂330 0.5-1份、引发剂0.15份、碳酸钙0.075份。The method for calculating the diameter reduction of the fluorosilicon-modified PERT barrier lining pipe according to claim 1, wherein the functional inner layer (1) comprises the following components: in parts by weight: 50-60 parts of PERTⅡ pellets, 30-40 parts of PE pellets, 10-15 parts of fluorine-containing monomer, 0.5-1 part of antioxidant 330, 0.15 parts of initiator, and 0.075 parts of calcium carbonate.
  3. 如权利要求1所述的采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，有限元软件中建模为联立三大基本方程求解：As claimed in claim 1, the fluorine-silicon modified PERT barrier liner pipe diameter reduction calculation method using finite element algorithm is characterized in that, the modeling in the finite element software is to solve three basic equations simultaneously:
    1)平衡方程1) Balance equation
    Figure PCTCN2021120678-appb-100003
    Figure PCTCN2021120678-appb-100003
    Figure PCTCN2021120678-appb-100004
    Figure PCTCN2021120678-appb-100004
    式中f表示摩擦力；where f is the friction force;
    2)物理方程(应力与应变的关系)2) Physical equation (relationship between stress and strain)
    Figure PCTCN2021120678-appb-100005
    Figure PCTCN2021120678-appb-100005
    Figure PCTCN2021120678-appb-100006
    Figure PCTCN2021120678-appb-100006
    Figure PCTCN2021120678-appb-100007
    Figure PCTCN2021120678-appb-100007
    式中E为杨氏模量，v为泊松比；Where E is Young's modulus, v is Poisson's ratio;
    3)变形协调方程(位移与应变的关系)3) Deformation coordination equation (relationship between displacement and strain)
    Figure PCTCN2021120678-appb-100008
    Figure PCTCN2021120678-appb-100008
    式中σ为主应力，τ为切应力，ε和γ为应变。In the formula, σ is the principal stress, τ is the shear stress, ε and γ are the strains.
  4. 如权利要求3所述的采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，应力分量和应变分量与角度θ无关，σ r＝P，将步骤3)和步骤5)得到的P min和P C依次代入以上所有方程中联立求解，求解得到对应的径向应变ε r的分布，进行厚度方向的积分计算，即得到径向整体变形量，即缩径量L min和L max。 As claimed in claim 3, the fluorine-silicon modified PERT barrier liner diameter reduction calculation method using the finite element algorithm is characterized in that the stress component and the strain component have nothing to do with the angle θ, σr =P, and step 3) Substituting the P min and P C obtained in step 5) into all the above equations to solve simultaneously, the corresponding radial strain ε r distribution is obtained by solving the solution, and the integral calculation in the thickness direction is carried out to obtain the radial overall deformation, that is, the shrinkage Diameter L min and L max .
  5. 如权利要求4所述的采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，厚度方向的积分计算式为As claimed in claim 4, the fluorine-silicon modified PERT barrier liner pipe diameter reduction calculation method using finite element algorithm is characterized in that the integral calculation formula in the thickness direction is:
    Figure PCTCN2021120678-appb-100009
    Figure PCTCN2021120678-appb-100009
    其中D为外径，d为内径。Where D is the outer diameter and d is the inner diameter.
  6. 如权利要求1所述的采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，最小剪切强度τ min≥0.15MPa。 The method for calculating the diameter reduction of the fluorine-silicon modified PERT barrier liner using the finite element algorithm according to claim 1, characterized in that the minimum shear strength τ min ≥ 0.15MPa.
  7. 如权利要求1所述的采用有限元算法的氟硅改性PERT阻隔内衬管缩径量计算方法，其特征在于，D的取值范围为50mm-315mm，t的取值范围为0.05D-0.15D。The method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner pipes according to claim 1, wherein the value range of D is 50mm-315mm, and the value range of t is 0.05D- 0.15D.
  8. 如权利要求1所述的采用有限元算法的氟硅改性PERT阻隔内衬管 缩径量计算方法，其特征在于，步骤5)中的f 0≥0.5％。 The method for calculating the diameter reduction of fluorine-silicon modified PERT barrier liner using finite element algorithm according to claim 1, characterized in that f 0 in step 5) is ≥0.5%.
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CN113836656A (en) 2021-12-24

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