JB/T 9176-1999 Method for compiling process quotas for material consumption of stamping parts
Some standard content:
JB/T9176--1999
This standard is a revision of JB/Z282-87 Stamping Material Consumption_Process Quota Calculation Method. During the revision, the prefix was added, and the chapters were edited, but the main technical content remained unchanged. This standard replaces J1B3/Z282--87 from the date of implementation. Appendix A of this standard is the appendix of the standard.
Appendix B and Appendix C of this standard are both informative appendices. This standard was proposed and managed by the National Technical Committee for Forging Standardization. The responsible drafting unit of this standard: China First Tractor Group Corporation Stamping Plant. The main drafters of this standard: Wang Wenhui and Shi Dingyong. 218
1 Scope
Machinery Industry Standard of the People's Republic of China
Technological norm for stamping part material consumption
Compiling method
Compiling mcthod of technological normfor stamping part material consumption This standard specifies the compilation principles and methods for technological norm for stamping part material consumption JB/T 9176 - 1999
Replaces JB/Z 28287
This standard applies to ordinary blanking and stamping parts in batch production of plates, coils and strips. For materials used in electrical 1 silicon steel, you can refer to the technical elements of the process quota for material consumption of stamping parts. 2.1 Quota composition
2.1.1 Cutting loss
2.1.1.1 When the plate is cut into bad materials (strips), the residual material generated in the length and width direction of the plate; 2.1.1.2 For the shearing method of one piece of material, the residual material is the sum of all the scraps generated during the shearing process; 2.1.1.3 For coils and strips, the residual material also includes the cut head and tail of the material; 2.1.1.4 Cutting loss in plate cutting. 2.1.2 Stamping loss
2.1.2.1 Process loss: refers to the various process allowances required in the production process of stamping parts (such as: the overlap of blanking parts, the trimming allowance of drawing parts, etc.).
2.1.2.2 Design loss: refers to the structural waste of stamping parts (such as: various shapes of holes in stamping parts, etc.). 2.1.3 Net weight of parts
The net weight of parts refers to the weight of finished parts that meet the requirements of product drawings (excluding the weight of various coatings). 2.2 Calculation method
2.2.1 Material selection method
According to the rough size of the stamping parts, reasonable layout is carried out, and the material specifications that are suitable and economically reasonable are selected. The number of stamping parts that can be made is calculated according to the specifications, and the loss of scraps generated is spread over each stamping part to calculate the material consumption process quota. The material selection method is mainly suitable for enterprises engaged in batch production. 2.2.1.1 The material consumption process quota of sheet metal stamping parts is calculated according to formula (1): C
Wherein: C is the material consumption process quota of a single stamping part, kg, G is the weight of the sheet metal (calculated by the length and width of the sheet metal specified in the standard plus 1/2 of the tolerance), kg; N is the number of stamping parts that can be stamped out of the sheet metal, which depends on the layout of the unfolded material on the sheet metal surface. a) For single-row layout (see Figure 1), the number of stamping parts that can be stamped out of the sheet metal is calculated according to formula (2) to formula (7): B, - D + 2
Approved by the State Machinery Industry Bureau on June 24, 1999 (1)
Implemented on January 1, 2000
Wherein B,—strip width, mm;
D—blank diameter, mm;
6—edge overlap, mm.
Where: A
Feed, mm;
Overlap, mm.
Number of strips cut from sheet metal (nt):
Where: L--
Length of sheet metal, mm.
Where: B-Width of sheet metal, mm.
JB/T9176—1999
(Take integer)
(Take integer)
（5）
When B is less than the minimum edge width allowed by the shearing machine, a value equal to the minimum edge width must be subtracted from L or B, and then the number of strips is calculated.
Number of stamping parts that can be made from each strip (n2): n2
Where: L-length of strip metal, mm.
Number of stamping parts that can be made from each sheet (N):
α(take integer)
b) For multi-row parallel layout (see Figure 2), the number of stamping parts that can be made from the sheet is calculated according to formula (8) and formula (9): Strip width:
B, = nD+2b + (n- 1)a
Where: np
Number of rows of blanking parts layout.
The calculation method for the number of strips cut into sheets (nl) is the same as that for single-row layout, calculated according to formula (4) or formula (5). 220
·（6）
(7）)
Number of stamping parts that can be made from each strip (n2):
JB/T 9176--1999
Number of stamping parts that can be made from each steel plate (N) is calculated according to formula (7). L
c) Multiple rows of staggered layout (see Figure 3), the number of stamping parts that can be stamped from the sheet is calculated according to formula (10) to formula (13): Figure 3
B, =D + 26+(D +a)cosα(np
-1/2 of the interior angle of the equilateral triangle, (°); before the other symbols. In the formula, α-
The number of strips cut into the sheet
The number of stamping parts that can be made from each strip (n2): When the decimal part of the second \ is less than 0.5:
ng =n,
When the decimal part of the second \ is greater than 0.5:
（11）
（12）
LTwo~ take the integer.
In the formula:
JB/T 9176--1999
The number of stamping parts (N) that can be made from each steel plate is calculated according to formula (7)nr
d) For more complex layout (see Figure 4), the number of stamping parts that can be made from the plate is calculated according to formula (14): The number of strips cut into the plate (nt) is calculated according to formula (4) or formula (5). The number of stamping parts that can be made from each strip (n2):n2
In the formula: 1-... refers to the distance between the center of the first stamping part and the feed end face B, mm; the other symbols are before. Figure 4
The number of stamping parts (N) that can be made from the plate is calculated according to formula (7). 2.2.1.2 The material consumption process quota for coil and strip stamping parts shall be calculated according to formula (15): C = g(1 + K)
Wherein: (- material consumption per single stamping part.T process quota, kg; g gross\- gross weight of a single stamping part (calculated according to the size of the stamping part).kg; K- the percentage of coil (strip) head and tail losses that should be shared by the stamping part. 13)
·(14)
(15)
2.2.1.3 Calculation method for material consumption process quota, surplus material utilization rate, waste material utilization rate and guarantee rate of stamping parts produced using surplus materials and structural waste materials.
a) Calculation method for material consumption process quota: Based on the shearing pattern drawing, the single-piece consumption process quota of the stamping part is calculated according to formula (1), but it is not included in the material consumption process quota of the whole machine product. b) Calculation method of surplus material utilization rate: surplus material utilization rate refers to the percentage of surplus material generated by sheet metal stamping parts (see Figure 5) that is utilized. Calculate according to formula (16):
K tea-
surplus material utilization rate, %;
where: K spring-
N--the number of type A stamping parts that can be made from sheet metal; Nnh
× 100%
.The remaining material of type A stamping parts can be used to make the number of type B stamping parts n. -The number of type A parts required for a single product
The number of type B parts required for a single product.
（16）
c) Calculation method of waste utilization rate: The waste utilization rate refers to the percentage of parts punched with structural waste of stamping parts that are utilized, and is calculated according to formula (17):
K凌一
× 100%
Wherein: K
Waste utilization rate, %;
JB/T 91761999
…The number of pieces required for a single product to punch another type of stamping part with waste: The number of pieces of another type of stamping part that can be punched with waste; The number of stamping parts required for a single product,
d) Calculation method of surplus and waste guarantee rate: The surplus guarantee rate and waste guarantee rate refer to the degree to which stamping parts using surplus or waste can meet the material needs of the product, expressed as a percentage, as shown in Figure 5. "A"—the waste material generated in the length direction of the plate; "B"—the waste material generated in the width direction of the plate; Jia—the main stamping part produced by the plate; Yi—the stamping part produced by using the waste material "A" generated by the production of part A is calculated according to formula (18) and formula (19): Kxiangbao-
Kfubai
wherein: Kmiscellaneousbao-waste guarantee rate;
Kdegreebao"
waste guarantee rate.
2.2.1.4 Calculation method of material utilization rate:
X 100%
refers to the percentage of the net weight of parts to the material consumption process quota, which indicates the degree of material utilization. It is calculated according to formula (20): net × 100%
Where: Kli—material utilization rate of a single stamping part, %; gnet—net weight of a single part, kg,
—material consumption of a single stamping part. 1. Process quota, kg. C
*（20）
When Kli represents the material utilization rate of a product, gnet should be the sum of the net weights of the parts of a product, and C should be the material consumption process quota of a product.
2.2.2 Coefficient method
JB/T 9176-1999
The method of calculating the material consumption process quota according to the material utilization rate or the residual rate of the material during the blanking process of the stamping parts. 2.2.2.1 The material consumption process quota is calculated by the blanking utilization rate method (K, coefficient method) according to formula (21): C-
Where: C-—the material consumption process quota of a single stamping part, kg, g gross———the gross weight of a single stamping part, which includes the blanking cut, kg; K1—the blanking utilization rate, %.
The blanking utilization rate is calculated according to formula (22):
Where: G gross
X 100%
·The total weight of the various stamping parts produced during the feeding period;
-The total weight of the materials required during the feeding period. W
2.2.2.2 The material process quota is calculated by using the material waste utilization rate method (K coefficient method) according to formula (23): c=fk
Where: g gross—the gross weight of a single stamping part, kg; K material waste rate, %.
The material waste rate is calculated according to formula (24):
Where: G Wei—
-the total weight of waste generated during the feeding period, kg. 2.2.2.3 The calculation method of material utilization rate K Li is the same as formula (20). 224
（21）
·（22）
（23）
...( 24 )
JB/T9176--1999Www.bzxZ.net
Appendix A
(Appendix to the standard)
Detailed list of material consumption and process quotas for stamping parts The basic contents of the detailed list of material consumption and process quotas for stamping parts are shown in Table A1. Table A1
Material name
Part number
Part name
Instructions for filling in the form:
Part net weight
Single piece rough
Sheet material or residual material
Single piece consumption
Number of stamping parts that can be madeProcess quota
(pieces)
Utilization rate
Number of pieces per machineConsumption per machine
(pieces)
Utilization rate
A1Under the same brand, same specification, and same standard, parts punched with raw materials are arranged in the first order according to the sequence number, and parts punched with residual and waste materials are arranged in the last order according to the sequence number.
A2Due to different calculation methods for material consumption process quotas, you can fill in the form according to your own needs. For example: using the material selection method to calculate material consumption If the process quota is consumed, the "material utilization rate" column does not need to be filled in. A3 For parts produced using surplus or scrap materials, the surplus or scrap materials of a certain part, the utilization rate and the guarantee rate should be indicated in the remarks column. A4 How to fill in this table:
Columns 1 to 2: Fill in according to the provisions of the parts list. Column 3: Can be determined by calculation or weighing.
Column 4: Refers to the rough size of the unpunched or the width of the stamping strip multiplied by the feed distance. Column 5: Calculate the weight according to the dimensions in Column 4. Column 6: Refers to a sheet or a piece of surplus material, and the number of stamping parts that can be made according to the layout drawing. Column 7: The weight of the standard sheet divided by the number of stamping parts that can be made from the sheet or surplus material. Column 8: Model refers to the product model. This column can be added as needed, and the number of pieces per unit should be filled in according to the parts drawing list. Column 9: Use the single-piece consumption process quota multiplied by the number of pieces per unit. Use surplus , parts produced from scrap materials are not filled in. Column 10: Divide the gross weight of a single piece by the process quota for consumption of a single piece. Column 11: Divide the net weight of the part by the process quota for consumption of a single piece. Column 12: Fill in as needed.
Appendix B
(Suggested Appendix)
Example of calculation method for process quota for material consumption of sheet metal stamping parts: There is a stamping part, the part number is 15.47.119, the part name is "shield guard", 2 pieces per car, steel grade Q215, material thickness is B
1.5mm, outer diameter is $228mm±2mm, other dimensions are shown in Figure Bl, calculate the process quota for material consumption of a single stamping part. 225
JB/T9176—1999
228±2
B1.1 According to the process calculation, no Finally, trim the edges, and the blanking diameter D is $267mm. Perform layout (see Figure B2) to confirm the strip width. According to formula (2), the strip width Bl is calculated to be 271mm. 2
2 Select a plate with a length L of 1700mm and a width B of 850+°mm for layout, and calculate the number of stampings that can be made from each plate B1.2
.
1700+15
According to formula (4) and formula (6), each plate can produce 3 strips, each strip can produce 6 stamping parts, and the number of stamping parts that can be made from each plate N is 3×6=18 pieces.
B1.3 The process quota of single-piece material consumption is calculated according to formula (1), that is: C=%G
The calculation of the weight of the steel plate is calculated by considering 1/2 of the tolerance of the length and width, that is: G 1 707. 5 X 855 X 1. 5 X 7. 85 X 106 17. 19 kgC
B2 Calculation of surplus material utilization rate and guarantee rate
In addition, stamping part 15.32.456, part name "locking plate", 3 pieces per car, using the surplus material "A\87>850" shown in Figure B3. The part graphic size is shown in Figure B4.
JB/T 9176--1999
After layout (see Figure B5), according to formula (6), the surplus material can be made into 12 pieces of 15.32.456\locking plates. According to formula (16), the surplus material utilization rate can be calculated as:
18×100%
12 × 2
225% (>100% means 100% is used)
According to formula (18), the guarantee rate of the remaining material for 15.32.456\locking piece" is calculated as follows: Kmiscellaneous guarantee"
X100%=44.4%
This means that the remaining material "A" of 15.32.456\locking piece after using up 15.47.119 "protective tile" can only meet 44.4% of its required amount, and the remaining insufficient part must be found separately.
B3 structural waste Calculation of utilization rate and guarantee rate 15.47.119\protective tile" has a structural waste with a diameter of 130, which can be used for 15.32.456\locking piece". Each piece of structural waste can be used to punch one piece.
According to formula (17), the utilization rate of structural waste is calculated as: 12×100%=150% (>100% means 100% is utilized) K degree-
According to formula (19), the guarantee rate of structural waste for 15.32.456\locking piece\ is calculated as: K degree guarantee
X 100% = 66.6%
B4 Fill in the stamping parts material consumption process quota list Based on the above data, after calculation, the data in the list can be obtained: Material name Cold steel plate, steel grade Q215 Specification (15±0.12)×850*°×1700~15 Standard GB/T11253-1989
Part number
15.47.119 Protective tile
15.32.456 Locking piece
Single piece rough
271 X268. 50. 86
0.02972x69.5
JB/T9176—1999
Single piece consumption of sheet or surplus
Can be stamped
(pieces)
Process quota
Appendix C
(suggestive appendix)
(pieces)
Overlap and edge values of blanking and stamping parts
Utilization rate
Utilization rate
Use 15.47.119
Residue ~A\100%
Utilization, guarantee rate
Use its structural waste
$130100% utilization
Utilization, guarantee rate
The overlap value (a) and the overlap value along the edge (b) of ordinary steel plate blanking parts are shown in Table C1. Other materials need to multiply the coefficient Kyd, see table (2 Table C1
Material thickness
Non-circular
1>100~200
1>200~~300
Reciprocating feeding
Automatic feeding
Material name
High carbon hard steel plate
Medium carbon semi-hard steel plate
Brass plate
Coefficient Kyd
JB/T 9176—1999
Material name
Copper plate
Coefficient Kyl
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