1、UDC 621.96 : 001.4 DEUTSCHE NORMEN October 1972 Begriffe der Stanztechnik; Fertigungsverfahren und Werkzeuge zum Zerteilen The severing processes mainly used in stamping practice are those of shear cutting and wedge-action cutting. The tools used for severing in stamping practice are thus grouped in
2、to shear cutting tools, wedge-action cutting tools and special tools. The process mainly used is shear cutting which, according to DIN 8588, is described in brief as cutting, so that the shear-action cutting tools are referred to for short as cutting tools. The terms adopted from DIN 8588 for the pr
3、oduction processes are identified by the process code number appended each time in brackets. The definitions adopted from DIN 8588 concerning these terms are marked by a vertical bar at the left-hand edge. Contents Page Page 1. Individual processes and individual process tools 1 1.2 Wedge-action cut
4、ting 6 1.1 Cutting (shear cutting) 1 1.2.1 Knife cutting 6 . . . 1.1.1 Blanking 1 1.2.2 Incising 7 1.1.2 Cropping 2 1.3 Special processes 7 1.1.3 Piercing 3 1.3.1 Plunging 7 1.1.4 Releasing 4 2. Processes tied to a special type of tool 7 1.1.5 Notching 4 2.1 Cutting against elastic pad 7 1.1.6 Trimm
5、ing . 4 2.2 Fine-edgeblanking 8 i .1 .7 shaving . 5 3. 5 3.1 Progressive cutting 8 1.1.8 Parting 3.2 Combination blanking and piercing 9 1.1.9 Nibbling 6 . . . Multiple processes using multiple process tools . 8 . . 1. Individual processes and individual process tools 1.1 Cutting (shear cutting) (3.
6、1.1 1 Cutting means the severing of work- pieces by two cutting edgeswhich move I past one another. The cut part is either the intermediate shape or the finished shape of a work- piece. 1.1.1 Blanking (3.1.1.1) Blanking is complete cutting along a cutting line closed in itself for produc- I ing the
7、external shape of the cut part. Tool: Blanking tool 1.1.1.1 Blanking with blanking tools Blanking with blanking tools produces congruent cut parts (Fig. 3). Congruent cut parts are termed blanks. With blanks the burr is on the side of the workpiece facing the punch. Scrap through blanking Figure 1.
8、Figure 2. Figure 3. Starting shape Production sequence Final shape (Cut part) Continued on pages 2 to 9 Explanations on page 1 O I DIN 9870 Teil 2 engl. Preisgr. 7 Vertr.-Nr. 0107 Sole sale rights of German Standards (DIN-Normen) are with Beuth Verlag GrnbH. Berlin 30 and Kln 1 07.80 Page 2 DIN 9870
9、 Part 2 V Feed scrap strip . rl seivdqe i Figure 4. Starting shape (Strip cut from strip or rolled strip) Figure 7. Starting shape (Strip cut from strip or rolled strip) Figure 10. Starting shape (Strip cut from strip or rolled strip) Figure 13. Starting shape (Strip cut from strip or rolled strip)
10、Fiqure 5. Production sequence Figure 6. Final shape (Blank) Cutting line Cropping Figure 8. Production sequence Figure 9. Final shape (Cropping) Figure 11. Figure 12. Production sequence Final shape (Single cropping (Cropping) without scrap) Cutting line Il/ o U Scrap at starr of strip Figure 14. Pr
11、oduction sequence (Double cropping without scrap) Figure 15. Final shapes (Croppings) Only such cut parts whose congruence is guaranteed (Fig. 6) are entitled to be termed blanks. Dimensional deviations of the blanks among themselves depend on the stock, the type of tool and tool wear. They must lie
12、 with- in the tolerance assigned to the cut part. 1 .I .2 Cropping (3.1.1.3) Cropping is complete cutting in which a semi-finished part or finished part is separated from unfinished or semi- finished parts along an open-ended cutting line. Tool: Cropping tool 1.1.2.1 Cropping with cropping tools Cro
13、pping with cropping tools produces croppings the width of which depends on the stock (Fig. 9) unless the selvedges are additionally trimmed in the cropping tool. These cut parts are termed croppings (Figs 9, 12, 15, 18 and 21). The dimensional deviations of the cropped lengths depend on the accuracy
14、 of feed (Figs 8, 11 and 14). The croppings are therefore not absolutely congruent. 1.1.2.1.1 Cropping without scrap Cropping without scrap is complete cut- ting of the croppings from the stock without loss of material. The production process termed cropping without scrap can only be applied if the
15、croppings can be linked together without any gap. A distinction is made between single (Fig. 11) and multiple (Fig. 14) cropping. Tool: Cropping too1 for cropping without scrap Single-cropping tool for crop- ping without scrap or Mutiple-cropping tool for crop ping without scrap 1.1.2.1.1.1 Cropping
16、 without scrap, The burr on these croppings is on opposite sides (Fig. 12). 1 .I .2.1.1.2 Cropping without scrap, multiple With multiple cropping tools a distinction has to be made between those with multi- row blanked strip and double-cropping tools. The burr on the croppings from multi- row croppe
17、d strip is on opposite sides (Fig. 15). single DIN 9870 Part 2 Page 3 ,Punched cropping Scrap at start of strip Double cropping is complete cutting of croppings from the stock without loss of material by a punch having the same shape as the cropping (Fig. 17). Tool: Double cropping tool for cropping
18、 without scrap In double cropping the croppings passing through the die are of equal length, the dimensional variations of the offcut crop pings however depend on the accuracy of the feed. The burr is one-sided and is on the side of the workpiece facing the punch in the case of the punched cropping,
19、 and on the side remote from the punch in the case of the offcut cropping. 1 .I 2.1.2 Cropping with scrap Cropping with scrap is complete cutting of a cropping from the stock by a punch, the shape of which determines the scrap (Fig. 20). The burr on these croppings is one-sided and is on that side o
20、f the workpiece remote from the punch (Fig. 21). Tool : Cropping too1 for cropping with scrap Cropping tools for cropping with scrap are used when the croppings cannot be linked together without a gap or when the burr on the cropping is required on one side only. 1 .I .3 Piercing (3.1 .I .2) I workp
21、iece. Piercing is complete cutting along a cut- ting line closed in itself for the purpose of producing an inner shape in the Tool : Piercing tool 1.1.3.1 Piercing with piercing tools Piercing with piercing tools produces internal shapes (Figs 23,26 and 29). The burr is on the side of the workpiece
22、remote from the punch. Punch with two/ offcut Punch Workpiece punchI,T Punch -FI Figure 74. Production sequence (Knife cutting using a wedge-shaped cutting edge against a support) 1.1.8.1 Parting with parting tools Parting with parting tools produces several final shapes from a single starting shape
23、 (Figs 62,65,68 and 71). With parting without scrap (Figs 62 and 65) the burr is on the workpiece-side facing the punch in the case of the work- piece lying below the punch. In the case of the workpiece which is moved past the punch the burr is on the opposite side. With parting with scrap (Figs 68
24、and 71) the burr on both workpieces is on the side remote from the punch. 1.1.9 Nibbling (3.1.1.9) Nibbling is complete cutting in which parts of the material are cut off piece by piece along an open-ended cut line with the feed motion of the tool or workpiece chosen at will. Tool: Nibbling tool 1.1
25、.9.1 Nibbling with nibbling tools Nibbling with nibbling tools results in fresh, partially limited changes of form in the outer or inner boundaries of start- ing shapes (Fig. 73). The burr is on the workpiece side remote from the punch. 1.2 Wedge-action cutting (3.1.2) Wedge-action cutting is the se
26、vering of workpieces by means of one or two wedge-shaped cutting edges which force the workpiece material apart. 12.1 Knife cutting (3.1.2.1 ) Knife cutting is wedge-action cutting with a cutting edge of which the wedge forcesthe material apart along a cutting line which is open-ended or closed in i
27、tself. I Tool : Knife cutting tool (Fig. 74) DIN 9870 Part 2 Page 7 1.2.2 Incising (3.1.2.2) Incising is wedge-action cutting between two cutting edges which move towards each other so that their wedges force the material apart along a cutting line which is open-ended or closed in itself. Tool: Inci
28、sing tool (Fig. 75) 1.3 Special processes 1.3.1 Plunging (3.1.3.4) I bosses, serrations etc. 1.3.1.1 Plunging without scrap Plunging without scrap is used for making a hole combined with deformation of the rim to produce a plunged boss plus serra- tions. Plunging entails rupturing of the ma- terial
29、to form a hole combined with deforming of the rim to produce plunged Tool: Plunging tool for plunging without scrap (Fig. 76). 1.3.1.2 Plunging with scrap Plunging with scrap is used for producing a hole combined with deformation of the rim to make a plunged boss. To prevent the formation of serrati
30、ons on the boss, a slug is punched out when plunging with scrap. Tool: Plunging tool for plunging with scrap (Fig. 77). 2. Processes tied to a special type of tool 2.1 Cutting against elastic pad Cutting against elastic pad is complete cut- ting along a cutting line open-ended or closed in itself fo
31、r producing external and/or internal shapes by a form-related punch acting against an elastic pad. The parts produced are blanks (see Clause 1.1 -1.1) with or without internal shapes. The burr is on the workpiece side remote from the elastic pad. Tool: Cutting tool with elastic Pad (Fig. 78) Figure
32、75. Production sequence (Incising by two wedge-action cutting edges) Plunging punch r“i- Figure 76. Plunging tool Workpiece Bottom part of Figure 77. Plunging tool for plunging with scrap tool Ot tool (Rubber or elastic plastic material) Figure 78. Cutting tool with elastic pad Page 8 DIN 9870 Part
33、2 Pressure Plate (Blank holder) acting also as stripper Indentation Workpiece i Pressure pad acting also as knockout Figure 79. Fine-edge blanking tool Scrap through piercing Burr from blanking Punch Figure 80. Figure 81. Starting shape Production sequence (Strip or band) (Single-stage piercing prio
34、r to blanking) Figure 82. Final shape (Blank) Scrap through piercing I Figure 83. Figure 84. Starting shape Production sequence (Strip or band) (Two-stage piercing prior to blanking) Figure 85. Final shape (Blank) 2.2 Fine-edge blanking Fine-edge blanking is complete cutting for producing internal a
35、nd external shapes with cut surfacesof low surface roughness square to the face of the workpiece. Fine- edge blanking requires the material to be held in a manner suited to the blanking operation. Fine-edge blanking can be limited to given portions of the internal and external shapes. The position o
36、f the burr is dependent on the blanking process used. Tool: Fineedge blanking tool (Fig. 79) 3. Multiple processes using If the production of a workpiece requires two or more cutting processes to be per- formed by a single tool, consideration must be given to the sequence of cutting operations requi
37、red for producing the workpiece. The sequence givesrise to the terms pro- gressive cutting and combination blanking and piercing. The corresponding tools are multiple process tools which are termed progressive tools and combination blanking and piercing tools respectively. multiple process tools 3.1
38、 Porgressive cutting Progressive cutting is complete cutting of any desired internal and external shapes along a cutting line which is open-ended or closed in itself by the application of different cutting processes successively in direct sequence. Severing is effected in two or more steps (Figs 81,
39、84,87 and 90). Tool: Progressive cutting tool 3.1.1 Progressive cutting with progressive cutting tools Progressive cutting with progressive cutting tools requires strip or band as the starting shape. The external shape of the workpiece is imparted in the final stage by blanking (Figs 81 and 84) or c
40、ropping (Figs 87 and 90). All internal shapes and releasings are produced in one or more preceding stages. Since internal and ex- ternal shapes are produced successively, all feed discrepancies react on their relative position. In thecase of blanks produced by progres- sive cutting the burr is on al
41、ternate sides, .e. the inner shapes and releasings pro- duced in the preceding stages have their burr on the opposite side to that of the external shape (Fig. 82). DIN 9870 Part 2 Page 9 Scrap through piercing Scrap through releasing Figure 86. Figure 87. Starting shape Production sequence (Single-s
42、tage piercing and releasing prior to “cropping without scrap” The position of the burr in the case of croppings produced by progressive cutting depends on the cropping process used. The burr of internal shapes is on the work- piece side remote from the piercing punches. When cropping without scrap (
43、see Section 1 .I .2.1 .I .l) the burr on the external shape is on alternate sides. With double cropping (see Section 1 .I .2.1.1.2) the burr in the case of the punched croppings is on alternate sides, whilst in the case of the offcut croppings it is on the same side as that of the in- ternal shapes.
44、 When cropping with scrap (see Section 1 .I .2.1.2) the burr of the internal and external shapes is on the same side. 3.2 Combination blanking and piercing Combination blanking and piercing is complete cutting to produce blanks with internal shapes in such a manner that the external shape and intern
45、al shape(s) are produced in a single stroke along a cut- ting line which is either open-ended or closed in itself (Fig. 93). Figure 88. Final shape (Cropping) Scrap through piercing Scrap through cropping Punch with two cutting lines Figure 89. Figure 90 Starting shape Production sequence (Single-st
46、age piercing prior to ”cropping with scrap”) Tool: Combination blanking and _. - with combination blanking and - piercing tools I piercing tool 3.2.1 Combination blanking and piercing Combination blanking and piercing with combination blanking and piercing tools produces cut parts (Blanks) with con-
47、 gruent internal and external shapes. The burr of theexternal shapeand internal shape(s) is on the same side of the work- piece, which is the side facing the blanking punch. Figure 92 shape (Strip from strip Or rolled strip) Figure 91. Final shape (Cropping) Scrap through piercing Scrap strip Figure
48、 93. Figure 94. Production sequence Final shape (Blank) Further Standards Terms for stamping practice tools classification, see DIN 9869 Part 1 Terms for stamping practice tools, cutting tools, see DIN 9869 Part 2 Terms for stamping practice, production processes and tools for forming by bending, se
49、e DIN 9870 Part 3 Severing; classification, subdivision, terms, see DIN 8588 (New edition in course of preparation) Page 10 DIN 9870 Part 2 Explanations The laying down of standard nomenclature and corresponding definitions for these terms was started as long ago as 1950 with the setting up of the “Stamping tools“ Advisory Committee in the DIN. This coordination, which was essential for stamping practice, led, following the appearance of relevant publications, to the formation of the Advisory Committee entitled “Terms of production processes“ in the DIN. The systematic gro
