Some standard content:
Machinery Industry Standard of the People's Republic of China
JB/T8051—96
Specification for Calculation of Centrifuge Drum Strength
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Published on September 3, 1996
Ministry of Machinery Industry of the People's Republic of China
Implementation on July 1, 1997
JB/T805196
Appendix A and Appendix B of this standard are both indicative appendices.
This standard is proposed and managed by the National Technical Committee for Separation Machinery Standardization. The drafting units of this standard are: Guanjin University, Hebei Institute of Technology, Hefei General Machinery Research Institute, and China General Machinery Separation Machinery Industry Association. The main drafters of this standard are: Zhu Qixin, Cheng Jinfeng, Zhao Yang, Zhang Jianmin, and Zou Runtang. YCanPDFPDFtoXDLLTest
Standard of the Machinery Industry of the People's Republic of China
Specification for Calculation of Strength of Centrifuge Drum
JB/T 805196
This standard specifies the calculation of the hoop stress of the drum wall when the centrifuge drum is rotating, the selection of various coefficients, the strength verification method of the perforated drum, the method of calculating the stress distribution state of the centrifuge drum using the finite element method, and the determination and verification method of the fatigue strength under cyclic load. This standard is not suitable for centrifuge drums with uniform wall thickness (the main shaft is arranged horizontally or vertically). The drum wall can be perforated or not, and the drum can be lined, screened or not: the material of the drum must be ductile metal material, and the influence of operating temperature on the material has been considered in the selection of materials.
This standard does not apply to centrifuge drums under the following conditions: a) The ratio of drum wall thickness to radius / r>0.1; b) The kinetic energy of the load drum is less than 750J:
c) Household dehydration machines driven by electric motors; d) The peripheral speed of the drum is greater than 300m/s:
e) Specially used for machines
Industrial leadership
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2 Cited standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard was published, the versions shown were valid. All standards will be revised, and parties using this standard should discuss the possibility of using the latest version of the following standards. GB 307582
GB 1134589
3 Symbols
Metal axial fatigue test method
Manual ultrasonic flaw detection method and analysis of flaw detection results of steel welded chain 3.1 This standard adopts the following symbols:
A: load-bearing area of drum reinforcement, mm;
a: height of drum reinforcement hoop, mm;
b: axial center distance between two adjacent holes on the drum, mm;br: oblique center distance between two adjacent holes on the drum wall, mmd: opening diameter, mm;
e: thickness of reinforcement hoop (radial), mm: G: maximum allowable loading (mass), kgh: effective height of drum, mm:
H: length of generatrix of conical drum, mm;
K: coefficient of weld and opening;
K,: weld coefficient:
K., K,, K.; coefficient of opening of drum wall related to the position of opening; m: total mass of screen.kg;
Approved by the Ministry of Machinery Industry on September 3, 1996
Implementation on July 1, 1997
N: mother of drum Number of holes on the line:
N.: Number of reinforcing hoops:
JB/T8051-96
n1: Fatigue strength limit safety factor of drum material; 4: Apparent density reduction coefficient caused by opening holes in drum wall; : Small inner radius of conical drum, mm
T: Inner radius of drum or inner radius of large end of conical drum, mmrs: Average radius of drum wall or average diameter of large end of conical drum, mm; r: Inner radius of material ring, mm;
Z; Reinforcement hoop coefficient:
: Drum Angle between the connecting lines of the staggered holes on the wall (see Figure 2), (\); 9: Semi-cone angle of the conical drum, (\): 8: Drum wall thickness, mm;
: Equivalent thickness of the screen, mm
P: Density of the drum material, g/cm;
Ps: Density of the material or wet filter cake (maximum value) g/cm, 0: Density of the screen or lining material + g/cm\a1: Hoop stress of the drum wall when the empty drum rotates, MPa; g: Hoop stress of the drum caused by the centrifugal pressure of the uniformly distributed material, MPa.. yaanppriportoxDll Test
.#YanP
Grass multi-life by ring
a: tensile strength of drum material, MPa:,: service point of drum material, MPa;
1: fatigue strength limit of drum material, MPa:at: total hoop stress in drum wall, MPa;w: allowable angular velocity, rad/s.
4 Hoop stress in drum wall when drum rotates
The hoop stress in drum wall when drum rotates can be divided into three types: hoop stress in drum wall when empty drum rotates, effective wall hoop stress generated by centrifugal pressure of material equal load in cylindrical drum, and hoop stress in drum wall generated by centrifugal pressure of material equal load in conical drum. 4.1 Hoop stress in the drum when the drum rotates idle The hoop stress in the drum wall when the drum rotates idle should be calculated according to formula (1): d, = 10gP
where g is selected according to 5.5. For a drum without holes = 1, the schematic diagram of the centrifuge drum structure is shown in Figure 1.
JB/T8051-96
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Figure 1 Schematic diagram of the centrifuge drum structure
4.2 Hoop stress on the drum wall caused by the centrifugal pressure of the material in the cylindrical drum The hoop stress on the drum wall caused by the centrifugal pressure of the material in the cylindrical drum should be calculated according to the two cases of uniform mass distribution and non-uniform mass distribution of the material load.
4.2.1 The hoop stress of the drum wall generated by the material load with uniform mass distribution (such as liquid, flowing thick slurry, etc.) shall be calculated according to formula (2) and formula (3). 4.2.1.1 When the material density 0 is known,
8,=10*[(-)r/(28)]
4.2.1.2 When the total mass of the material is known:
S=103a/(Gr,/2xh8)
422 The hoop stress of the drum wall generated by the material load with non-uniform mass distribution (such as textiles, fur, etc.) shall be calculated according to formula (4). a,=10-*rG(rir)/[3xh8(ri-r)]-42.3 If the conveyor belt is single or equipped with a screen, the effective hoop stress of the drum wall generated by the centrifugal pressure of the mass of the drum or the screen must be calculated. The equivalent thickness of the screen in the cylindrical drum should be approximately calculated according to formula (5): 2r,ho
4. 2. 3. 1
4. 2.3. 2
When the density of the screen material is known:
o,=10-\*(pri8,/8)
When the total mass of the screen material is known:
d,=10*[mr,/(2h8)]
National The hoop stress of the drum wall caused by the centrifugal pressure of the material load in the conical drum43
JB/T 805196
4.3.1 The hoop stress of the drum caused by the material load with uniform mass distribution (such as liquid, flowing thick slurry, etc.) should be calculated according to formula (8). =10*p()r/(28·cos)
4.3.2 If the drum is sealed or equipped with a screen, the hoop stress caused by the mass of the seal or screen must be calculated. The equivalent thickness of the screen in the conical drum should be approximately calculated according to formula (9): 8,
(r+r)Hp
4.3.2.1
When the density of the screen material is known:
a,=10*(pr8./8)
When the total mass of the screen material is known:
4.3.2.2
6,=10 *wmri/[x(r,+r)H8].
5 Selection of various coefficients
5.1 Reinforcement hoop coefficient
5.1.1 The drum can be equipped with reinforcement hoops: When reinforcement hoops are installed, their spacing should be symmetrical. (9)
5.1.2 The reinforcement hoops have the function of reinforcing the drum wall. The reinforcement hoop coefficient Z can be used to correct it. This coefficient is determined by stress calculation. The method used for stress calculation should be adapted to the structural shape of the drum. 5.1.3 When reinforcement hoops are not used, the reinforcement hoop coefficient is taken as: 2=1, 5. 1.4
When reinforcement hoops are installed, the reinforcement screen coefficient is calculated according to formula (12), 1+NA/()
5.2 Weld seam coefficient YCanPDEPDFtoX DLL Test5.2.1 The mechanical properties of the weld should be equivalent to or better than the mechanical properties of the drum wall material. The weld coefficient is introduced to consider the weakening of the strength at the weld.
5.2.2 For welds that are inspected by 100% radiographic inspection or other equivalent flaw detection methods in accordance with GB11345, the weld coefficient should be: K,=0.95.
5.3 Opening coefficient
5.3.1 The openings on the drum weaken the strength of the drum wall on the one hand, and reduce the apparent density of the drum wall on the other hand. The opening coefficient and apparent density reduction coefficient are used to consider the influence of the openings on the strength of the drum. 5.3.2 When the holes are evenly distributed on the drum wall, the opening coefficients K, and K, are related to the opening positions, see formula 2. Their values are determined by formula (13) and formula (14). When used, the smaller value of K: K, and K should be used: K, = (b, d) / b, *
K, = V (bt-d) / br
Where: V.
is a function of the angle α, V = (1 + tg\a) / (1 + 3tg\a) / t, V can be obtained from Table 1. Table 1
Comparison table of value V and angle α
JB/T8051—96
Figure 2 Relationship diagram of hole position
For single row holes and one row of holes near the bottom of the drum and (or) one row of holes near the upper ring edge, the hole coefficient is determined by formula (15) 5.3.3
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5.4 Weld and hole coefficient
5.4.1 In the reprint hole coefficient, the stress concentration at the edge of the hole is not considered. The weld area should not be opened. 5.4.2 When the weld area is not opened, the K value should be the smaller value of K;, K, K, and K. 5.4.3 When opening holes in the coal seam area is unavoidable, the K value should be the smaller value of K,, K, and K, multiplied by the weld coefficient K. 5.5 Apparent density reduction coefficient caused by opening holes in drum wall The apparent density reduction coefficient caused by opening holes in drum wall is calculated according to formula (16). b,b.·sinand/41—nd/(4b,bz·sina)bb,?sina
6 Strength verification of perforated drum
Total hoop stress of cylindrical perforated drum
Total hoop stress of cylindrical perforated drum should be calculated according to the two cases of uniform and non-uniform distribution of material load. 6.1.1 For material loads with uniform mass distribution (such as liquids, flowing slurries, etc.): , = (, ++,) / K ≤ [] | | tt | | 6. 1. 1. 1 | | tt | | 6. 1. 1. 2 | | tt | | When the material density is known, calculate according to formula (18): o | | tt | | (ri - r) r | | tt | | Lapori + | | tt | | When the total mass of the material is known, calculate according to formula (19): 8.r | | tt | | Gr, X10 *, mr, X10 * | | tt | | kx10Lgp + | | tt | | 2 yuan hoz | | tt | | For material loads with non-uniform mass distribution (such as textiles, fur, etc.): 2 # hz | | tt | | d, (o, + d, +o,) / K ≤ [| | tt | | 6. 1. 2. 1
When the total mass of the material is known, it is calculated according to formula (21), (15)
(16)）
JB/T 8051-96
+G(r)x10+mmx10≤[0]
\xioLapri+
3xh8z(=r)+
2元hoz
For a cylindrical drum without holes, the total annular stress can be calculated according to formulas (17) to (21), where g=1, K=K. 6.2 Total hoop stress of conical drum with hole 6.2.1 The total hoop stress of conical drum is calculated according to formula (22): o,=(a +o,+a,)/K≤[]-
6.2.2 When the material density is unknown, it is calculated according to formula (23): (ri-)r
aX1oLapi+p 2.p+
For conical drum without hole, the total hoop stress can be calculated according to formula (22) and formula (23), where g=1, K=K,. 6.3 Allowable stress of material
Due to factors not taken into account in this standard, the calculated hoop stress shall not exceed the smaller of the following two allowable stress values. [a]
d,≤0.50d..d,≤0.33d
wherein is the servitude point of steel with obvious servitude phenomenon; for steel with no obvious servitude point, 6, is replaced by the stress when 0.2% residual elongation is produced; for austenitic steel, 0, is replaced by the stress when 1.0% residual elongation is produced, which is determined by actual measurement of the sample. 7 Application of Finite Element Method to Calculate the Stress Distribution State of Centrifuge Drum For the calculation of the stress distribution state of the geometric shape
Finite Element Method
7.1 Transfer to each YeanPDF.PDFtox DLL, the axisymmetric finite element program or the three-dimensional finite element program can be used. 7.2 For drums with reinforced screens, when there is an interference plate, the finite element method should be used to calculate the sleeve force and the stress of the drum body wall under different interferences to determine the appropriate interference amount. 7.3 The bottom of the drum, the liquid blocking plate and other parts with complex geometric shapes do not need to be simplified in geometry, and can be directly calculated by the finite element method. 7.4 The three-dimensional finite element program can be used to calculate the stress of the entire drum with holes. 8 Determination and verification of fatigue strength under cyclic loads For materials used to manufacture centrifuges that withstand a high number of cyclic loads (such as top-suspended centrifuges for sugar production and tripod centrifuges operated in intervals), it is recommended to determine their fatigue strength under 2×10* cycles of stress and conduct strength verification. 8.1 Determination of fatigue strength
Fatigue strength tests and sample preparation should comply with the provisions of GB3705. 8.2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1. The safety factor shall be at least 1.2. That is: (25)
Total hoop stress 9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.cop
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)*
K,=V(bt-d)/br
Wherein: V.
Function of angle α, V=（1+tg\a)/(1+3tg\a)/t, V can be obtained from Table 1. Table 1
Comparison table of values V and angle α
JB/T8051-96
Figure 2 Relationship diagram of opening position
For a single row of holes and a row of holes close to the bottom of the drum and (or) a row of holes close to the upper ring edge, the opening coefficient is determined by formula (15) 5.3.3
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5.4 Weld and opening coefficient
5.4.1 In the reprint opening coefficient, the stress concentration at the edge of the hole is not considered. The weld zone should not be perforated. 5.4.2 When the weld zone is not perforated, the K value should be the smaller value of K, K, K, and K. 5.4.3 When perforation in the coal seam zone is unavoidable, the K value should be the smaller value of K, K, K, and K multiplied by the weld coefficient K. 5.5 The apparent density reduction coefficient caused by perforation in the drum wall The apparent density reduction coefficient caused by perforation in the drum wall is calculated according to formula (16). b,b.·sinand/41—nd/(4b,bz·sina)bb,?sina
6 Strength verification of perforated drum
Read the hoop total stress of cylindrical perforated drum
The hoop total stress of cylindrical perforated drum should be calculated according to the two cases of uniform mass distribution and non-uniform mass distribution of material load. 6.1.1 For material loads with uniform mass distribution (such as liquids, flowing slurries, etc.): , = (, ++,) / K ≤ [] | | tt | | 6. 1. 1. 1 | | tt | | 6. 1. 1. 2 | | tt | | When the material density is known, calculate according to formula (18): o | | tt | | (ri - r) r | | tt | | Lapori + | | tt | | When the total mass of the material is known, calculate according to formula (19): 8.r | | tt | | Gr, X10 *, mr, X10 * | | tt | | kx10Lgp + | | tt | | 2 yuan hoz | | tt | | For material loads with non-uniform mass distribution (such as textiles, fur, etc.): 2 # hz | | tt | | d, (o, + d, +o,) / K ≤ [| | tt | | 6. 1. 2. 1
When the total mass of the material is known, it is calculated according to formula (21), (15)
(16)）
JB/T 8051-96
+G(r)x10+mmx10≤[0]
\xioLapri+
3xh8z(=r)+
2元hoz
For a cylindrical drum without holes, the total annular stress can be calculated according to formulas (17) to (21), where g=1, K=K. 6.2 Total hoop stress of conical drum with hole 6.2.1 The total hoop stress of conical drum is calculated according to formula (22): o,=(a +o,+a,)/K≤[]-
6.2.2 When the material density is unknown, it is calculated according to formula (23): (ri-)r
aX1oLapi+p 2.p+
For conical drum without hole, the total hoop stress can be calculated according to formula (22) and formula (23), where g=1, K=K,. 6.3 Allowable stress of material
Due to factors not taken into account in this standard, the calculated hoop stress shall not exceed the smaller of the following two allowable stress values. [a]
d,≤0.50d..d,≤0.33d
wherein is the servitude point of steel with obvious servitude phenomenon; for steel with no obvious servitude point, 6, is replaced by the stress when 0.2% residual elongation is produced; for austenitic steel, 0, is replaced by the stress when 1.0% residual elongation is produced, which is determined by actual measurement of the sample. 7 Application of Finite Element Method to Calculate the Stress Distribution State of Centrifuge Drum For the calculation of the stress distribution state of the geometric shape
Finite Element Method
7.1 Transfer to each YeanPDF.PDFtox DLL, the axisymmetric finite element program or the three-dimensional finite element program can be used. 7.2 For drums with reinforced screens, when there is an interference plate, the finite element method should be used to calculate the sleeve force and the stress of the drum body wall under different interferences to determine the appropriate interference amount. 7.3 The bottom of the drum, the liquid blocking plate and other parts with complex geometric shapes do not need to be simplified in geometry, and can be directly calculated by the finite element method. 7.4 The three-dimensional finite element program can be used to calculate the stress of the entire drum with holes. 8 Determination and verification of fatigue strength under cyclic loads For materials used to manufacture centrifuges that withstand a high number of cyclic loads (such as top-suspended centrifuges for sugar production and tripod centrifuges operated in intervals), it is recommended to determine their fatigue strength under 2×10* cycles of stress and conduct strength verification. 8.1 Determination of fatigue strength
Fatigue strength tests and sample preparation should comply with the provisions of GB3705. 8.2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1. The safety factor shall be at least 1.2. That is: (25)
Total hoop stress 9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.cop
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)*
K,=V(bt-d)/br
Wherein: V.
Function of angle α, V=（1+tg\a)/(1+3tg\a)/t, V can be obtained from Table 1. Table 1
Comparison table of values V and angle α
JB/T8051-96
Figure 2 Relationship diagram of opening position
For a single row of holes and a row of holes close to the bottom of the drum and (or) a row of holes close to the upper ring edge, the opening coefficient is determined by formula (15) 5.3.3
When YGaPDFPDFtoX DLL Test
5.4 Weld and opening coefficient
5.4.1 In the reprint opening coefficient, the stress concentration at the edge of the hole is not considered. The weld zone should not be perforated. 5.4.2 When the weld zone is not perforated, the K value should be the smaller value of K, K, K, and K. 5.4.3 When perforation in the coal seam zone is unavoidable, the K value should be the smaller value of K, K, K, and K multiplied by the weld coefficient K. 5.5 The apparent density reduction coefficient caused by perforation in the drum wall The apparent density reduction coefficient caused by perforation in the drum wall is calculated according to formula (16). b,b.·sinand/41—nd/(4b,bz·sina)bb,?sina
6 Strength verification of perforated drum
Read the hoop total stress of cylindrical perforated drum
The hoop total stress of cylindrical perforated drum should be calculated according to the two cases of uniform mass distribution and non-uniform mass distribution of material load. 6.1.1 For material loads with uniform mass distribution (such as liquids, flowing slurries, etc.): , = (, ++,) / K ≤ [] | | tt | | 6. 1. 1. 1 | | tt | | 6. 1. 1. 2 | | tt | | When the material density is known, calculate according to formula (18): o | | tt | | (ri - r) r | | tt | | Lapori + | | tt | | When the total mass of the material is known, calculate according to formula (19): 8.r | | tt | | Gr, X10 *, mr, X10 * | | tt | | kx10Lgp + | | tt | | 2 yuan hoz | | tt | | For material loads with non-uniform mass distribution (such as textiles, fur, etc.): 2 # hz | | tt | | d, (o, + d, +o,) / K ≤ [| | tt | | 6. 1. 2. 1
When the total mass of the material is known, it is calculated according to formula (21), (15)
(16)）
JB/T 8051-96
+G(r)x10+mmx10≤[0]
\xioLapri+
3xh8z(=r)+
2元hoz
For a cylindrical drum without holes, the total annular stress can be calculated according to formulas (17) to (21), where g=1, K=K. 6.2 Total hoop stress of conical drum with hole 6.2.1 The total hoop stress of conical drum is calculated according to formula (22): o,=(a +o,+a,)/K≤[]-
6.2.2 When the material density is unknown, it is calculated according to formula (23): (ri-)r
aX1oLapi+p 2.p+
For conical drum without hole, the total hoop stress can be calculated according to formula (22) and formula (23), where g=1, K=K,. 6.3 Allowable stress of material
Due to factors not taken into account in this standard, the calculated hoop stress shall not exceed the smaller of the following two allowable stress values. [a]
d,≤0.50d..d,≤0.33d
wherein is the servitude point of steel with obvious servitude phenomenon; for steel with no obvious servitude point, 6, is replaced by the stress when 0.2% residual elongation is produced; for austenitic steel, 0, is replaced by the stress when 1.0% residual elongation is produced, which is determined by actual measurement of the sample. 7 Application of Finite Element Method to Calculate the Stress Distribution State of Centrifuge Drum For the calculation of the stress distribution state of the geometric shape
Finite Element Method
7.1 Transfer to each YeanPDF.PDFtox DLL, the axisymmetric finite element program or the three-dimensional finite element program can be used. 7.2 For drums with reinforced screens, when there is an interference plate, the finite element method should be used to calculate the sleeve force and the stress of the drum body wall under different interferences to determine the appropriate interference amount. 7.3 The bottom of the drum, the liquid blocking plate and other parts with complex geometric shapes do not need to be simplified in geometry, and can be directly calculated by the finite element method. 7.4 The three-dimensional finite element program can be used to calculate the stress of the entire drum with holes. 8 Determination and verification of fatigue strength under cyclic loads For materials used to manufacture centrifuges that withstand a high number of cyclic loads (such as top-suspended centrifuges for sugar production and tripod centrifuges operated in intervals), it is recommended to determine their fatigue strength under 2×10* cycles of stress and conduct strength verification. 8.1 Determination of fatigue strength
Fatigue strength tests and sample preparation should comply with the provisions of GB3705. 8.2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1. The safety factor shall be at least 1.2. That is: (25)
Total hoop stress 9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.cop
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)2
When the material density is known, calculate according to formula (18): o
(ri-r)r
Lapori+
When the total mass of the material is known, calculate according to formula (19): 8.r
Gr,X10*，mr,X10*
kx10Lgp+
2 yuanhoz
For material loads with uneven mass distribution (such as textiles, fur, etc.): 2#hz
d,(o,+d, +o,)/K≤[
6. 1. 2. 1
When the total mass of the material is known, calculate according to formula (21), (15)
(16)）
JB/T 8051-96
+G(r)x10+mmx10≤[0]
\xioLapri+
3xh8z(=r)十
2元hoz
For a cylindrical drum without holes, the total annular stress can be calculated according to formulas (17) to (21), where g=1, K=K. 6.2 Total hoop stress of conical drum with hole 6.2.1 The total hoop stress of conical drum is calculated according to formula (22): o,=(a +o,+a,)/K≤[]-
6.2.2 When the material density is unknown, it is calculated according to formula (23): (ri-)r
aX1oLapi+p 2.p+
For conical drum without hole, the total hoop stress can be calculated according to formula (22) and formula (23), where g=1, K=K,. 6.3 Allowable stress of material
Due to factors not taken into account in this standard, the calculated hoop stress shall not exceed the smaller of the following two allowable stress values. [a]
d,≤0.50d..d,≤0.33d
wherein is the servitude point of steel with obvious servitude phenomenon; for steel with no obvious servitude point, 6, is replaced by the stress when 0.2% residual elongation is produced; for austenitic steel, 0, is replaced by the stress when 1.0% residual elongation is produced, which is determined by actual measurement of the sample. 7 Application of Finite Element Method to Calculate the Stress Distribution State of Centrifuge Drum For the calculation of the stress distribution state of the geometric shape
Finite Element Method
7.1 Transfer to each YeanPDF.PDFtox DLL, the axisymmetric finite element program or the three-dimensional finite element program can be used. 7.2 For drums with reinforced screens, when there is an interference plate, the finite element method should be used to calculate the sleeve force and the stress of the drum body wall under different interferences to determine the appropriate interference amount. 7.3 The bottom of the drum, the liquid blocking plate and other parts with complex geometric shapes do not need to be simplified in geometry, and can be directly calculated by the finite element method. 7.4 The three-dimensional finite element program can be used to calculate the stress of the entire drum with holes. 8 Determination and verification of fatigue strength under cyclic loads For materials used to manufacture centrifuges that withstand a high number of cyclic loads (such as top-suspended centrifuges for sugar production and tripod centrifuges operated in intervals), it is recommended to determine their fatigue strength under 2×10* cycles of stress and conduct strength verification. 8.1 Determination of fatigue strength
Fatigue strength tests and sample preparation should comply with the provisions of GB3705. 8.2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1. The safety factor shall be at least 1.2. That is: (25)
Total hoop stress 9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.cop
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)2
When the material density is known, calculate according to formula (18): o
(ri-r)r
Lapori+
When the total mass of the material is known, calculate according to formula (19): 8.r
Gr,X10*，mr,X10*
kx10Lgp+
2 yuanhoz
For material loads with uneven mass distribution (such as textiles, fur, etc.): 2#hz
d,(o,+d, +o,)/K≤[
6. 1. 2. 1
When the total mass of the material is known, calculate according to formula (21), (15)
(16)）
JB/T 8051-96
+G(r)x10+mmx10≤[0]
\xioLapri+
3xh8z(=r)十
2元hoz
For a cylindrical drum without holes, the total annular stress can be calculated according to formulas (17) to (21), where g=1, K=K. 6.2 Total hoop stress of conical drum with hole 6.2.1 The total hoop stress of conical drum is calculated according to formula (22): o,=(a +o,+a,)/K≤[]-
6.2.2 When the material density is unknown, it is calculated according to formula (23): (ri-)r
aX1oLapi+p 2.p+
For conical drum without hole, the total hoop stress can be calculated according to formula (22) and formula (23), where g=1, K=K,. 6.3 Allowable stress of material
Due to factors not taken into account in this standard, the calculated hoop stress shall not exceed the smaller of the following two allowable stress values. [a]
d,≤0.50d..d,≤0.33d
wherein is the servitude point of steel with obvious servitude phenomenon; for steel with no obvious servitude point, 6, is replaced by the stress when 0.2% residual elongation is produced; for austenitic steel, 0, is replaced by the stress when 1.0% residual elongation is produced, which is determined by actual measurement of the sample. 7 Application of Finite Element Method to Calculate the Stress Distribution State of Centrifuge Drum For the calculation of the stress distribution state of the geometric shape
Finite Element Method
7.1 Transfer to each YeanPDF.PDFtox DLL, the axisymmetric finite element program or the three-dimensional finite element program can be used. 7.2 For drums with reinforced screens, when there is an interference plate, the finite element method should be used to calculate the sleeve force and the stress of the drum body wall under different interferences to determine the appropriate interference amount. 7.3 The bottom of the drum, the liquid blocking plate and other parts with complex geometric shapes do not need to be simplified in geometry, and can be directly calculated by the finite element method. 7.4 The three-dimensional finite element program can be used to calculate the stress of the entire drum with holes. 8 Determination and verification of fatigue strength under cyclic loads For materials used to manufacture centrifuges that withstand a high number of cyclic loads (such as top-suspended centrifuges for sugar production and tripod centrifuges operated in intervals), it is recommended to determine their fatigue strength under 2×10* cycles of stress and conduct strength verification. 8.1 Determination of fatigue strength
Fatigue strength tests and sample preparation should comply with the provisions of GB3705. 8.2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1. The safety factor shall be at least 1.2. That is: (25)
Total hoop stress 9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.cop
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1, and the safety factor shall be at least 1.2. That is: (25)
Total hoop stress9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.cop
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)2 Check of fatigue strength
After the hoop stress in the weld area and the opening area is calculated, the fatigue strength shall be checked according to the fatigue strength limit of the drum material specimen under cyclic load obtained in 8.1, and the safety factor shall be at least 1.2. That is: (25)
Total hoop stress9
A1.1 Cylindrical drum
A1.1.1 Cylindrical drum without holes
Material by density:
Material by mass:
A1.1.2 Cylindrical drum with opening
Material by density:
Material by mass:
JB/T 805196
Appendix A
Summary of formulas for calculating drum strength
(suggested appendix)
(ri-r)
kx10Lori+0
Gr,X10°
xxiaeri+
nr,X10*
2 yuanh8z
(rt-ri)r
+ps 8z
YCanPDERDFtoXLTest
A1.2 Conical drum
A1.2.1 Circular shaped non-porous drum
Material density meter:
xo[eri+p: %c0p
A1.2.2 Conical perforated drum
Material by density:
kx10Lapri+p.20.copWww.bzxZ.net
Drum wall original thickness 5
A2.1 Cylindrical drum
A2.1.1 Cylindrical drum without holes
Material by density:
()+22,,
22(Lo.K2×10t)
Material by mass:
(Gr, +mr,Z)X10
=2xhZ([]K×10°-0,r)
A2.1.2 Cylindrical perforated drum
Material according to density:
P(rri)r,+2Ze,o,r
2z([oK×10gPr)
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