GB/T 15716-1995 Method for evaluating the process performance of coal screening equipment
Some standard content:
National Standard of the People's Republic of China
Method for evaluating the process performance of coal sizing equipment-
Performance evaluation
1 Subject content and scope of application
GB/T 15716-1995
This standard specifies the evaluation indicators, data verification, curve drawing and form filling of the process performance of coal sizing equipment. This standard is applicable to the evaluation of the process performance of various screening equipment in the preparatory screening, inspection screening, final screening and desludging screening operations of coal.
2 Evaluation indicators
2.1 There are three indicators for evaluating the process performance of coal sizing equipment: screening efficiency, average distribution error and total mismatch content. 2.1.1 Screening efficiency
2.1.1.1 Screening efficiency is calculated according to formula (1)
7=E+E,-100
Wherein: —Screening efficiency, %;
Positive matching efficiency of coarse particles, %;
E——Positive matching efficiency of fine particles, %;
—Product yield on the sieve, %,
Fi -. × O
O—Content of coarse particles in the product on the sieve (percentage of this grade), %;F-Calculated content of coarse particles in the feed, %;
Fr---Calculated content of fine particles in the feed;%;O--Content of fine particles in the product on the sieve (percentage of this grade), %. (1)
·(3)
O. and O, can be obtained from the particle size characteristic curve of the product on the screen, while F and Fr can be obtained from the calculated particle size characteristic curve of the feed material (see 4.1). 2.1.1.2 When calculating the screening efficiency, the coarse particles and fine particles are generally divided by the specified particle size. When identifying the screening equipment, they are divided according to the distribution particle size.
2.1.2 Average distribution error
2.1.2.1 The average distribution error is calculated according to formula (4) State Administration of Technical Supervision approved on October 17, 1995 416
PE - PE + PE
（4）
Implementation on June 1, 1996
Where: PEm-
Average distribution error;
Upper distribution error;
Lower distribution error;
GB/T 15716--1995
The particle size value on the distribution curve corresponding to a distribution rate of 75%; the distribution particle size, that is, the particle size value on the distribution curve corresponding to a distribution rate of 50%; (5)
(6)
S25The particle size value on the distribution curve corresponding to a distribution rate of 25%: S75, S, and S25 are all obtained from the distribution curve (see 4.2). 2.1.2.2 When the distribution curve is very irregular and it is impossible to obtain S5 and S2s at the same time, PE. or PE. can be used instead of PEm. 2.1.3 Total mismatch content
2.1.3.1 The total mismatch content is calculated according to formula (7): ma= me+ mf
m = ×UX 100
m = YX 0X 100
Where: mo--total mismatch content, %,
m. —Content of coarse particle mismatch, i.e. the percentage of coarse particles in the undersize product to the input material, %; mi-Content of fine particle mismatch, i.e. the percentage of fine particles in the oversize product to the input material, %; undersize product yield, %;
U.-Content of coarse particles in the undersize product (percentage of this grade), %. U. Obtained from the particle size characteristic curve of the product under the screen (see 4.1. 2.1.3.2 When calculating the total mismatch content, the distribution particle size is generally used to divide the coarse particles and fine particles. (7)
(8)
2.2 Principles of indicator application: Screening efficiency and average distribution error should be used when technical appraisal of newly developed equipment, acceptance of newly put into production equipment or important production technology inspection. The total mismatch content can be used as a supplementary evaluation indicator. Routine inspection of screening equipment is not restricted by this standard. 2.3 Calculation of indicators
2.3.1 A set of evaluation indicators (screening efficiency, average distribution error and total mismatch content) can be calculated for each layer of screen surface. For a screening machine with n layers of screen surface, according to the needs At most n groups of indicators can be calculated: when calculating the i-th layer indicator, the feed, the product on the sieve and the product under the sieve of the i-th layer should be used separately.
2.3.2 The product yield should be directly determined by the metrological method as much as possible. When measurement is difficult, it can be calculated according to the method provided in Appendix A. 2.3.3 The numerical value of the evaluation index is rounded to two decimal places. 3 Data verification
3.1 Mean square error test
Whether the product yield is obtained by metrological method or calculation method, the mean square error shall be used to verify the correctness and regularity of the product yield and screening data.
3.1.1 Mean square error is calculated according to the following formula
Where: α—mean square error;
(10 )
GB/T 15716—1995
△ is the difference between the calculated content of each particle size in the input material and the measured content in the input material; N is the number of particle sizes in the screening data used;
M is the number of products in the screening operation.
3.1.2 The critical value of the mean square error is generally 3.0, and it is qualified if it is less than 3.0. When the input particle size is greater than 25mm, or is coal slime, the critical value can be relaxed to 4.0.
3.1.3 If the △ values of two adjacent particle sizes are both greater than 3.0 and have opposite signs, the two grades can be merged before calculating α, but the combined particle size grades should still meet the requirements of C in Article 3.2. 3.1.4 If the △ values are neatly divided into two groups near the allocated particle size, with one positive and one negative sign, it may be caused by unreasonable product yield values (for example, one group greater than the allocated particle size). If one group is positive and the other group is negative, it may be that the on-screen product rate is too large; otherwise, it may be too small). The product yield should be further verified. If no error in the yield can be found after verification, the assessment result is considered invalid. 3.2 If one of the following situations occurs during the assessment process, the assessment result is considered invalid. a. The product yield is negative;
b. Except for the edge particle size, there is no monotonous increasing or decreasing sequence relationship between the distribution rate and the particle size. c. The number of sieved particle sizes of the feed and product are all less than 6, or the number of particle sizes of individual products is less than 4. 4 Curve drawing
4.1 Particle size characteristic curve
The particle size characteristic curve includes the measured feed particle size characteristic curve, the calculated feed particle size characteristic curve and the particle size characteristic curve of each screened product. 4.1.1 Generally, only the cumulative particle size characteristic curve from fine to coarse is drawn. 4.1.2 Particle size characteristic curves are generally drawn using rectangular coordinates, with the horizontal axis representing the particle size value, and the scale value can be determined according to the particle size distribution range of the feed material; the vertical axis represents the cumulative value of the content of each particle size; generally a constant scale is used. 4.1.3 The particle size characteristic curve should be drawn as smooth and unidirectionally inclined as possible. 4.2 Particle size distribution curve
4.2.1 Generally, only the product distribution curve on the sieve is drawn. 4.2.2 Calculation of distribution rate
Single-layer screen:
Double-layer screen: The distribution rate of the first layer of screen surface is the same as that of the single-layer screen, and the distribution rate of the second layer of screen surface is E2
Multi-layer screen: Calculate the distribution rate of the first layer, the second layer, and the nth layer of screen surface respectively, where the distribution rate of the i-th layer of screen surface is 0
Where. E\.2,*...,E,
is the distribution rate of the 1st layer, the 2nd layer,...the nth layer of screen surface, %,: (11)
·( 12)
（13）
O,O2.，O--is the distribution of a certain particle size in the screen products of the 1st and 2nd i-th screen surfaces (accounting for the total input), %;
Fi,F2,..\,Fr--
is the content of a certain particle size in the calculated material of the 1st and 2nd i-th screen surfaces (accounting for the total input), %; the input of the i-th screen surface is the residual value after deducting the screen products of the i-1th screen surface from the i-1th layer input.
4.2.3 The rectangular coordinates are generally used to draw the distribution curve. Its horizontal axis represents the geometric mean particle size value, and its scale value can be determined according to the particle size distribution range of the input material; its vertical axis represents the distribution rate; %; generally a constant scale is used. 4.2.4 If the upper limit of the particle size is S1 and the lower limit is S2, then the geometric mean particle size is √s1×S2; when the upper and lower limits of the edge level are unclear, it can be estimated empirically based on the specific conditions of the feed. GB/T15716—1995
5 The distribution curve should be drawn according to the principle of minimizing the sum of the squares of the distances from each data point to the curve in the ordinate direction, and should maintain a smooth 4.2.5
S\ shape.
5 Form filling
5.1 The evaluation results should be filled in the screening equipment process performance evaluation report form, and its format is shown in Appendix B. 5.2 The calculation table format used in the assessment process can refer to Appendix C. 419
A1 General algorithm
GB/T 15716-
—1995
Appendix A
Algorithm for the yield of screening products
(Supplement)
The problem of calculating the yield of screening products can be expressed as an optimization problem, that is, the objective function constraint condition
In the formula; M the number of screening products
x,G,/100)2 = Mim
N the number of particle size grades of screening tests on human materials and products; Goi-the output of the jth particle size grade in the actual input material, %; G,-the output of the i-th particle size grade in the i-th product, %. (A1)
·(A2)
Wherein, the product numbers are arranged from large to small according to the particle size, i=1 represents the largest screen product, i=N represents the smallest screen product, and the rest represent intermediate products.
The yield of the first product, %.
Using the Lagrange multiplier method, (A1) and (A2) can be transformed into an unconstrained optimization problem. Y,G,/100)2 + A(
Where: ^—
-Lagrange multiplier.
Introduce the vector expression of the unknown number
100'100,
100)— Min
100＇2
·（A4）
Taking the partial derivatives of the left and right sides of (A3) with respect to the elements of vector X and setting them equal to zero, we obtain a linear equation system of order M+1, whose matrix expression is:
where the elements of the coefficient matrix A are
(MIiM)
(k=M+1 and i=M+1)
(1 ≤M and i=M+l,k=M+1 and l≤i≤M) the elements of the right-hand side vector B are
·（A5）
GB/T15716—1995
(≤k≤M)
·（A7)
Solve X from equation (A5) and substitute the first M elements into the corresponding elements on the right-hand side of equation (A4) to obtain the yield Y(i -1,2,....M) of the screening product
The general algorithm described above is suitable for solving by programming an electronic computer. A2 Two-product screening
For two-product screening (i.e., M=2), the solutions to the optimization problems (A1) and (A2) are go1×100
= 100 —
(A8)Where:
A3 Three-product screening
G2i)(Gli — G2i)
For three-product screening (i.e., M-3), the solutions to the optimization problems (A1) and (A2) are go1822 - go2g12 × 100
g11g22—g12g12
g01812
g11g22 — g12g12
× 100
, = 100 2
In formulas (A12) and (A13), go and gu are substituted into formulas (A10) and (A11) respectively according to M=3, and the remaining go2
— G3i)(G2; — Gai）
— G3i)(Gzi — Gsi)
Appendix C gives an example of calculating the product yield of two products screening. .(A8)
（A9）
（A10）
（A1）
（A12）
·（A13）
·（A14）
·（A15）
（A16)
（A17)
Test No.
Technical characteristics of screening equipment
Equipment name
Model, specification
Effective area, m2
Number of vibrations, r/min
Amplitude, mm
Inclination angle of screen surface,.
Screen surface material
Screen surface structure
Screen hole shape
Opening rate, %
Screen hole size
Form filling instructions
GB/T15716—1995
Appendix B
Format of the report on the evaluation of the process performance of screening equipment (reference)
Test location
Feed characteristic index
Material name
Feed particle size (upper limit—lower limit)
(S), mm
Feed quantity (Q), t/h
Feed ash content (Aa), %
Feed moisture
(dry screening)
Flushing amount
(wet screening)
(external Mt).%|| tt||(Total M), %
(W), m/h
Content of hard-to-screen particles, %
Product yield under the screen
Test date
Year, month, day
Evaluation index and calculation parameters
Screen surface level
Screening efficiency
Average distribution error
Total mismatch content
(mo), %
Distribution particle size
(S,), mm
Specified particle size
(Sa), mm
Screening test data
Mean square error (o)
Three layers Three layers
Except the two evaluation indexes of screening efficiency and average distribution error, other items can be filled in as much as possible according to the specific situation. If the number of screen layers exceeds three, the relevant content can be appropriately added in the table. When PE. When PE and PE cannot be obtained at the same time, only PE or PEI can be filled in, and the name of the "average distribution error" column should be changed accordingly. B1.3
The moisture content of the feed should be filled in as much as possible as the external moisture, rather than the full moisture; when the external moisture value is lacking, the full moisture value can be filled in. B1.4
B1.5 Some other relevant information that is considered necessary can be recorded after the table. B2
Content of difficult-to-screen particles
B2.1 Definition of difficult-to-screen particles
With S (1+0.25) as the upper limit and S. (1-0.25) as the lower limit, the particle size with these upper and lower limits is called difficult-to-screen particles. B2.2 Determination of the content of difficult-to-screen particles
Respectively with S. With S (1+0.25) and S (1-0.25) as the horizontal coordinate values, look up the calculated feed curve in the particle size characteristic curve diagram (such as Appendix C Figure C1), and get two vertical coordinate values - cumulative content. Subtract these two values, and the difference is the percentage of difficult-to-screen particles. 422
GB/T 15716—1995
Appendix C
Example of calculation of process performance of coal screening equipment (reference)
C1In May 1983, the performance of XY type vibrating screen was measured at ×× Coal Preparation Plant of ×× Mining Bureau. The screen specification was B×L=1200mm×7300mm, the effective screen area was 7.7m2, the vibration frequency was 830r/min, the amplitude was 5.5mm, the screen plate inclination was 15°, the screen surface was punched steel plate, the screen hole was circular, the aperture was 13mm, and the opening rate was 40.4%; the feed was anthracite raw coal, the feed rate was 200t/h, the ash content was 23.6%, the particle size was 50~0mm, and the total moisture content was 8.5%. Table C1 Particle size composition of feed and product
Particle size mm
25～13
Calculate product yield
Feed output
Cumulative output
Oversize product
Cumulative output
Table C2. 2. Product yield calculation table
Oversize product outputUndersize product output
Goj—Gzi
Gri-- Gzi
=Z(G =Ga) × (Gu
- G22 × 100%
(G— G2)2
Undersize product
Cumulative output
(Gli--G2)2
(Goj -G2;) × (Gi—
.= 100% -—% = 57.69%
C3 Calculate the feed particle size composition and distribution rate
× 100%
25～13
GB/T15716—1995
Table C3 Calculation of feed size composition and distribution rate calculation table Geometric mean particle size Actual feed
(/s,xs,)
Output (F)
Output of oversize products
Accounting for this level
Accounting for input
Output of undersize products
Accounting for this level
Accounting for input
Calculating the output of input
Accounting for this level
Cumulative level
Distribution rate
Note: 1. The upper limit of the +50mm level is considered to be 75mm, which is considered to be caused by the excessively large pieces in the undersize products when the 50mm mesh screen surface is screened, s,xS=75×50-61.2mm. The Sz of the 3~0mm level is taken as 0.08mm. 2. The content of each particle size in the input is calculated as the sum of the content of the particle size in each product (accounting for the input), that is, F (accounting for this level)-O (accounting for the input)+U (accounting for the input). 0 (accounting for input material)
3. Distribution rate ε-
X100%.
F\ (accounting for this grade)
C4 Mean square error calculation table of the difference between the actual input material and the calculated input material content of each gradeC4 Mean square error calculation table
Actual input material output
Calculated input material output
NN-M+1
Because. It is less than the critical value of 3.0, so it is considered qualified. C5 Drawing particle size characteristic curve and distribution curve 41.76
6—2+1
AFY—F
C5.1 Taking the particle size in Table C1 as the horizontal coordinate, the cumulative output of the feed, the cumulative output of the oversize product and the cumulative output of the undersize product as the vertical coordinate, the cumulative particle size characteristic curve of the measured feed, the oversize product and the undersize product can be drawn; taking the calculated cumulative output of the feed in Table C3 as the vertical coordinate, the calculated cumulative particle size characteristic curve of the feed can be drawn. The drawn cumulative particle size characteristic curve is shown in Figure C1. C5.2 Taking the "geometric mean particle size" in Table C3 as the horizontal coordinate and the distribution rate e as the vertical coordinate, draw the distribution curve. The drawn distribution curve is shown in Figure C2.
C6 Calculation of screening efficiency
C6.1 Determine the relevant data
GB/T15716—1995
Take the specified particle size S. =13mm, from Figure C1 (or Table C1), we can find O,=6.71%, so 0.=100%-0,=93.29%; from Figure C1 (or Table C3), we can find H=44.58%, so F=100%-Fr=55.42%; from C2, we know that =57.69%. C6.2 Calculation steps
E. = *x × 100% = 57.69%x3 29% × 100% = 97.11%,F
EL = -×0 × 100% = 44. 58%-57:69% ×6.71% × 100% = 91.32%,
so n=E. +E-100%=97.11%+91.32%-100%=88. 43%. C7 Calculate the distribution error
C7.1 Determine the relevant data
From Figure C2, we know that S.=12.00mm, Sz513.40mm, S2s=10.00mmC7.2 Calculation steps
Ses = 13. 4
= 1. 12, PE, =
PE.+PE1.12+1.20=1. 16.
Therefore PEm
C8 Calculate the total mismatch content
C8.1 Determine the relevant data
From Table C3, we know that %=42.31%, %=57.69%; and with S,-12.0mm, we can check Figure C1 to get U =6. 8%, O=5. 5%. C8.2 Calculation steps
m = × U. × 100% - 42.13% × 6.8% × 100% 2.88%,m = %. × 0 × 100% = 57.69% × 5.5% × 100% = 3.17%, so m = m. + mr = 2.88% + 3.17% = 6.05%. C9 Calculation of difficult-to-screen particle content
C9.1 Determine the upper and lower limits of the difficult-to-screen particle grade
The upper limit is S, × (1 + 0.25) = 12.0 × 1.25 = 15.0 mm, and the lower limit is S, × (10.25) = 12.0 × 0.75 = 9.0 mm. C9.2 Calculation steps
Use the upper and lower limits of the difficult-to-screen particle size to check the calculated feed particle size characteristic curve in Figure C1, and get ≥F(-15)=47.5%, ≥F(-9)35.0%, so ZF(-15) - ZFr-9) =47.5% -35.0% =12.5%. C10 Fill in the form
Fill in the screening equipment process performance evaluation table according to Appendix B. 425
Test No.
Technical features of screening equipment
Equipment name
Model.Specifications
Effective area, m
Vibration times.r/min
Breadth, mm
Screen surface inclination, (\)
Screen surface material
Screen surface structure
Screen hole shape
Opening rate, %
Screen hole size
Vibrating screenbzxZ.net
xY1200mm
X7300mm
Ordinary steel plate
Steel plate punching
GB/T 15716—1995
Screening Equipment Process Performance Evaluation Report
Test Location
×× Mining Bureau×× Coal Preparation Plant
Feed Characteristics Index
Feed Name
Feed Particle Size (Upper and Lower Limit)
(S), mm
Feed Quantity (Q), t/h
Feed Ash (Aa), %
Feed Moisture
(Dry Screening)
Water Quantity
(Wet Screening)
(External M)), %
(Total M.), %
(W), m/h
Content of Hard-to-Screen Particles, %
Product Yield of Underscreen Products
Screening Products
Anthracite Raw coal
Test date
July 3, 1988
Evaluation index and calculation parameters
Screen surface level
Screening efficiency
Average distribution error
Total mismatch content
(mo),%
Distribution particle size
(Sp),mm
Specified particle size
Screening test data
Mean square error (o)
[Screen] product
Figure C1 Particle size characteristic curve
Two-layer and three-layer
Additional instructions:
GB/T15716-1995
Figure C2 Distribution curve
This standard is proposed by the Ministry of Coal Industry of the People's Republic of China. This standard is under the jurisdiction of the National Coal Standardization Technical Committee. 30
This standard was drafted by the Coal Preparation Design Institute and the Tangshan Branch of the China Coal Research Institute. The main drafters of this standard are Xu Jun, Li Xuekun, Wang Mianxuan, Liu Zhaowo and Liu Chenglin. The Coal Preparation Design Institute is entrusted with the interpretation of this standard. 4271 Determine the relevant data
GB/T15716—1995
Take the specified particle size S. =13mm, and find out O.=6.71% from Figure C1 (or Table C1), so 0.=100%-0.=93.29%; and find out H=44.58% from Figure C1 (or Table C3), so F=100%-Fr=55.42%; and know from C2 that =57.69%. C6.2 Calculation steps
E. = *x × 100% = 57.69%x3 29% × 100% = 97.11%,F
EL = -×0 × 100% = 44. 58%-57:69% ×6.71% × 100% = 91.32%,
so n=E. +E-100%=97.11%+91.32%—100%=88. 43%. C7 Calculation of distribution error
C7.1 Determine relevant data
From Figure C2, we can find S.=12.00mm, Sz513.40mm, S2s=10.00mmC7.2 Calculation steps
Ses = 13. 4
= 1. 12, PE, =
PE.+PE1.12+1.20=1. 16.
Therefore PEm
C8 Calculation of total mismatch content
C8.1 Determine relevant data
From Table C3, we know that %=42.31%, %=57.69%; and with S,-12.0mm, we can check Figure C1 to get U =6.8%, O=5.5%. C8.2 Calculation steps
m = × U. × 100% - 42.13% × 6.8% × 100% 2.88%, m = %. × 0 × 100% = 57.69% × 5.5% × 100% = 3.17%, so m=m.+mr=2.88%+3.17%=6.05%. C9 Calculate the content of hard-to-screen particles
C9.1 Determine the upper and lower limits of the hard-to-screen particle size
The upper limit is S,×(1+0.25)=12.0×1.25=15.0mm, and the lower limit is S,×(10.25)=12.0×0.75=9.0mm. C9.2 Calculation steps
Use the upper and lower limits of the hard-to-screen particle size to refer to the calculated feed particle size characteristic curve in Figure C1, and obtain ≥F(-15)=47.5%, ≥F(-9)35.0%, so ZF(-15) - ZFr-9) =47.5% -35.0% =12.5%. C10 Fill in the form
Fill in the screening equipment process performance evaluation table according to Appendix B. 425
Test No.
Technical features of screening equipment
Equipment name
Model.Specifications
Effective area, m
Vibration times.r/min
Breadth, mm
Screen surface inclination, (\)
Screen surface material
Screen surface structure
Screen hole shape
Opening rate, %
Screen hole size
Vibrating screen
xY1200mm
X7300mm
Ordinary steel plate
Steel plate punching
GB/T 15716—1995
Screening Equipment Process Performance Evaluation Report
Test Location
×× Mining Bureau×× Coal Preparation Plant
Feed Characteristics Index
Feed Name
Feed Particle Size (Upper and Lower Limit)
(S), mm
Feed Quantity (Q), t/h
Feed Ash (Aa), %
Feed Moisture
(Dry Screening)
Water Quantity
(Wet Screening)
(External M)), %
(Total M.), %
(W), m/h
Content of Hard-to-Screen Particles, %
Product Yield of Underscreen Products
Screening Products
Anthracite Raw coal
Test date
July 3, 1988
Evaluation index and calculation parameters
Screen surface level
Screening efficiency
Average distribution error
Total mismatch content
(mo),%
Distribution particle size
(Sp),mm
Specified particle size
Screening test data
Mean square error (o)
[Screen] product
Figure C1 Particle size characteristic curve
Two-layer and three-layer
Additional instructions:
GB/T15716-1995
Figure C2 Distribution curve
This standard is proposed by the Ministry of Coal Industry of the People's Republic of China. This standard is under the jurisdiction of the National Coal Standardization Technical Committee. 30
This standard was drafted by the Coal Preparation Design Institute and the Tangshan Branch of the China Coal Research Institute. The main drafters of this standard are Xu Jun, Li Xuekun, Wang Mianxuan, Liu Zhaowo and Liu Chenglin. The Coal Preparation Design Institute is entrusted with the interpretation of this standard. 4271 Determine the relevant data
GB/T15716—1995
Take the specified particle size S. =13mm, and find out O.=6.71% from Figure C1 (or Table C1), so 0.=100%-0.=93.29%; and find out H=44.58% from Figure C1 (or Table C3), so F=100%-Fr=55.42%; and know from C2 that =57.69%. C6.2 Calculation steps
E. = *x × 100% = 57.69%x3 29% × 100% = 97.11%,F
EL = -×0 × 100% = 44. 58%-57:69% ×6.71% × 100% = 91.32%,
so n=E. +E-100%=97.11%+91.32%—100%=88. 43%. C7 Calculation of distribution error
C7.1 Determine relevant data
From Figure C2, we can find S.=12.00mm, Sz513.40mm, S2s=10.00mmC7.2 Calculation steps
Ses = 13. 4
= 1. 12, PE, =
PE.+PE1.12+1.20=1. 16.
Therefore PEm
C8 Calculation of total mismatch content
C8.1 Determine relevant data
From Table C3, we know that %=42.31%, %=57.69%; and with S,-12.0mm, we can check Figure C1 to get U =6.8%, O=5.5%. C8.2 Calculation steps
m = × U. × 100% - 42.13% × 6.8% × 100% 2.88%, m = %. × 0 × 100% = 57.69% × 5.5% × 100% = 3.17%, so m=m.+mr=2.88%+3.17%=6.05%. C9 Calculate the content of hard-to-screen particles
C9.1 Determine the upper and lower limits of the hard-to-screen particle size
The upper limit is S,×(1+0.25)=12.0×1.25=15.0mm, and the lower limit is S,×(10.25)=12.0×0.75=9.0mm. C9.2 Calculation steps
Use the upper and lower limits of the hard-to-screen particle size to refer to the calculated feed particle size characteristic curve in Figure C1, and obtain ≥F(-15)=47.5%, ≥F(-9)35.0%, so ZF(-15) - ZFr-9) =47.5% -35.0% =12.5%. C10 Fill in the form
Fill in the screening equipment process performance evaluation table according to Appendix B. 425
Test No.
Technical features of screening equipment
Equipment name
Model.Specifications
Effective area, m
Vibration times.r/min
Breadth, mm
Screen surface inclination, (\)
Screen surface material
Screen surface structure
Screen hole shape
Opening rate, %
Screen hole size
Vibrating screen
xY1200mm
X7300mm
Ordinary steel plate
Steel plate punching
GB/T 15716—1995
Screening Equipment Process Performance Evaluation Report
Test Location
×× Mining Bureau×× Coal Preparation Plant
Feed Characteristics Index
Feed Name
Feed Particle Size (Upper and Lower Limit)
(S), mm
Feed Quantity (Q), t/h
Feed Ash (Aa), %
Feed Moisture
(Dry Screening)
Water Quantity
(Wet Screening)
(External M)), %
(Total M.), %
(W), m/h
Content of Hard-to-Screen Particles, %
Product Yield of Underscreen Products
Screening Products
Anthracite Raw coal
Test date
July 3, 1988
Evaluation index and calculation parameters
Screen surface level
Screening efficiency
Average distribution error
Total mismatch content
(mo),%
Distribution particle size
(Sp),mm
Specified particle size
Screening test data
Mean square error (o)
[Screen] product
Figure C1 Particle size characteristic curve
Two-layer and three-layer
Additional instructions:
GB/T15716-1995
Figure C2 Distribution curve
This standard is proposed by the Ministry of Coal Industry of the People's Republic of China. This standard is under the jurisdiction of the National Coal Standardization Technical Committee. 30
This standard was drafted by the Coal Preparation Design Institute and the Tangshan Branch of the China Coal Research Institute. The main drafters of this standard are Xu Jun, Li Xuekun, Wang Mianxuan, Liu Zhaowo and Liu Chenglin. The Coal Preparation Design Institute is entrusted with the interpretation of this standard. 427%
Sieve hole size
Vibrating screen
xY1200mm
X7300mm
Ordinary steel plate
Steel plate punching
GB/T 15716—1995
Screening Equipment Process Performance Evaluation Report
Test Location
×× Mining Bureau×× Coal Preparation Plant
Feed Characteristics Index
Feed Name
Feed Particle Size (Upper and Lower Limit)
(S), mm
Feed Quantity (Q), t/h
Feed Ash (Aa), %
Feed Moisture
(Dry Screening)
Water Quantity
(Wet Screening)
(External M)), %
(Total M.), %
(W), m/h
Content of Hard-to-Screen Particles, %
Product Yield of Underscreen Products
Screening Products
Anthracite Raw coal
Test date
July 3, 1988
Evaluation index and calculation parameters
Screen surface level
Screening efficiency
Average distribution error
Total mismatch content
(mo),%
Distribution particle size
(Sp),mm
Specified particle size
Screening test data
Mean square error (o)
[Screen] product
Figure C1 Particle size characteristic curve
Two-layer and three-layer
Additional instructions:
GB/T15716-1995
Figure C2 Distribution curve
This standard is proposed by the Ministry of Coal Industry of the People's Republic of China. This standard is under the jurisdiction of the National Coal Standardization Technical Committee. 30
This standard was drafted by the Coal Preparation Design Institute and the Tangshan Branch of the China Coal Research Institute. The main drafters of this standard are Xu Jun, Li Xuekun, Wang Mianxuan, Liu Zhaowo and Liu Chenglin. The Coal Preparation Design Institute is entrusted with the interpretation of this standard. 427%
Sieve hole size
Vibrating screen
xY1200mm
X7300mm
Ordinary steel plate
Steel plate punching
GB/T 15716—1995
Screening Equipment Process Performance Evaluation Report
Test Location
×× Mining Bureau×× Coal Preparation Plant
Feed Characteristics Index
Feed Name
Feed Particle Size (Upper and Lower Limit)
(S), mm
Feed Quantity (Q), t/h
Feed Ash (Aa), %
Feed Moisture
(Dry Screening)
Water Quantity
(Wet Screening)
(External M)), %
(Total M.), %
(W), m/h
Content of Hard-to-Screen Particles, %
Product Yield of Underscreen Products
Screening Products
Anthracite Raw coal
Test date
July 3, 1988
Evaluation index and calculation parameters
Screen surface level
Screening efficiency
Average distribution error
Total mismatch content
(mo),%
Distribution particle size
(Sp),mm
Specified particle size
Screening test data
Mean square error (o)
[Screen] product
Figure C1 Particle size characteristic curve
Two-layer and three-layer
Additional instructions:
GB/T15716-1995
Figure C2 Distribution curve
This standard is proposed by the Ministry of Coal Industry of the People's Republic of China. This standard is under the jurisdiction of the National Coal Standardization Technical Committee. 30
This standard was drafted by the Coal Preparation Design Institute and the Tangshan Branch of the China Coal Research Institute. The main drafters of this standard are Xu Jun, Li Xuekun, Wang Mianxuan, Liu Zhaowo and Liu Chenglin. The Coal Preparation Design Institute is entrusted with the interpretation of this standard. 427
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.