TECHNICAL SPECIFICATIONS FOR PLASTIC INJECTION MOLDS
General specifications for thermoplastic molds 2.0 17/10/2005
CONTENTS CHAPTER “1” : Summary - Scope - Applicability - Responsibility - Revision document CHAPTER "2" : Definition of materials comprising the mold CHAPTER "3" : Mold standardization - Definition of mold CLASSES - Mold set-up and misc. - Papers and general technical notes - Mold general plates - Tolerances - Drawing numbering and issue CHAPTER "4" : Bill of materials CHAPTER "5" : Design methods – Mounting assemblies CHAPTER "6" : Standard – commercial parts CHAPTER "7" : Injection and Hot Runners CHAPTER "8" : Mold conditioning CHAPTER "9" : Hydraulic cylinders and Ejection CHAPTER "10" : Lifting eyebolts, Presses and misc. Calculations
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CHAPTER 1
SUMMARY SCOPE APPLICABILITY RESPONSIBILITY REVISION DOCUMENT
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CHAPTER 2
DEFINITION OF MATERIALS COMPRISING A THERMOPLASTIC INJECTION MOLD
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DEFINITION OF THE MATERIALS COMPRISING A THERMOPLASTIC INJECTION MOLD
SCOPE This DOCUMENT describes: - The types of steel normally used in mold construction. - The physical / mechanical requirements these materials must meet. METHODS Each type of steel must be identified according to EURONORM (EU) standard or, in the absence of EU correspondence, according to the standards for the individual CEN member states: UNI, DIN, (Werkstoff Nr.) or AFNOR. The following must be indicated for each material: - HEAT TREATMENT - PHYSICAL/MECHANICAL PROPERTIES: - CONDITION SUPPLIED (Forged, drawn, etc.) - Heat treatment with indication of hardness expressed in HB +/-5 tolerance - Tensile strain ( R, Rs ), with values expressed in daN/mm 2. IMPORTANT On parts requiring AMMONIA HARDENING, indicate “AMMONIA HARDENING TREATMENT TO BE CARRIED OUT AFTER FINISHING AND FITTING PART” on the part drawing On parts requiring SPECIAL SURFACE TREATMENTS (e.g.: PVD, TiN coating, etc..) mark these instructions on the drawing.
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RECOMMENDED MATERIALS STEL DENOMINATIONS
CONDITION SUPPLIED Werkstoff
numerical code
Alphanumerical code
(illegible)
HEAT TREATMENT MECHANICAL PROPERTIES
APPLICATIONS
FE 0B
(as per UNI EN 10025)
Ni Cr 1
(as per UNI EN 8550)
Cr NI Mo 4
(as per UNI EN 10083)
Cr Mo V5
(as per UNI EN ISO 4957)
Cr Mo 8
(as per UNI 2955)
Cr Mn Mi Mo 864
(as per UNI EN 4957)
C E
(as per UNI EN 10083)
C W
(as per UNI EN 10083)
HOT
LAMINATED
ANNEALED
PRE-TREATED
ANNEALED (HB=229)
PRE-TREATED
PRE-TREATED
NORMALIZED
NORMALIZED
ANNEALED
TEMPERED CASEHARDENED
HB=578/650
DEGASSED R = 80 daN/mm2
DEGASSED R = 100-115 daN/mm2
HB = 375-400
DEGASSED R = 100-110 daN/mm2
HB = 300-330
DEGASSED R = 110-110 daN/mm2
HB = 290-330
R = 65-74 daN/mm2
HB = 174-208
R = 65-70 daN/mm2
HB = 180-190
Brackets Support plates Expeller plates
Bracketing plates
Slideways Centring pins and
bushes Wear plates
Heads, Tie-bars, Tension organs, Support for extr.
Suports
Figure parts, carriages, male guides, sloping
columns
Figure parts, carriages,
inserted fixed blocks
Figure parts, carriages,
inserted fixed blocks
Figure parts for prototype molds, trestles, expeller
plates
Figure parts for prototype molds, trestles, expeller
plates
--------
Wr.1..5732
Wr.1.6511
Wr.1.2343
Wr.1.2311/1
2
Wr.1.2738
Wr.1.1191
Wr.1.1730
Materials with equivalent or superior characteristics are acceptable provided they are previously agreed with the Customer.
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STEEL APPLICATION STANDARDS
Knurled
Not knurled
PUNCH FINISH DIE
In the case of abrasive raw materials (glass fiber or flame resistant plastic), contact the Customer to define the materials to use. Do not use blocks in bronze and/or aluminum. If it is necessary to weld the punch or die, use the correct welding electrodes, making certain the mold is preheated and tempered as required, following current procedures for obtaining the best result. Welds must always be authorized by Customer. Carriages, moving parts and all fixed inserts must be realized in pretreated steel and subsequently ammonia hardened at sliding parts. Guides, slideways, mold guide/exp. Plate/incl column bushes, including the respective guide columns must be fully surface hardened to HB = 578-650. Where specifically required by customer, all the above parts must be commercially available in self-lubricating material (steel/bronze with graphite inserts). Injection bushes, slideways and mold positioning and centering plates must be fully surface hardened to HB=578-650. All steels for mold construction must be certified, proving physical/mechanical characteristics and heat treatments applied.
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CHAPTER 3
THERMOPLASTIC INJECTION MOLD STANDARDIZATION DEFINITION OF MOLD CLASSES MOLD SET-UP GENERAL MOLD PLATES - TOLERANCES TITLE BOXES AND GENERAL TECHNICAL NOTES DRAWING NUMBERING AND ISSUE
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MOLD STANDARDIZATION PURPOSE This DOCUMENT serves to unify molds with similar dimensions, in order to standardize parts comprising the molds. DEFINITION OF MOLD CLASSES Mold standardization is based on dimensions/weight, which determines the following "THREE CLASSES ":
SMALL
CLASS MOLDS MOLD WEIGHT (Kg)DIE
MEDIUM
LARGE
Where the dimensions of the molds are near to the upper limit of its class, We suggest passing to the next class up. For class “1” molds, preferably use commercially available normalized Mold Kit. The following is a list of the standard thicknesses of the parts in the table and annexed diagram:
Mobile side slab
PART CLASS “3” THICKNESS (mm)
CLASS “2” THICKNESS (mm)
Fixed side slab
Expeller slap
Exp counter-slab
Exp. monoslab
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STANDARD PLATE THICKNESSES
MOVING SIDE SLAB Class 2 = 48 Class 3 = 58
FIXED SIDE SLAB Class 2 = 48 Class 3 = 58
EXPELLER COUNTER-PLATE Class 2 = 58 Class 3 = 88
EXPELLER COUNTER-PLATE Class 2 = 22 Class 3 = 22
PUNCH DIE
EXPELLER MONOPLATEPLATE Class 2 = 75 mm Class 3 = 105 mm
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MOLD SET-UP Always mark the dimensions necessary for the start of the figure on drawings as MANDATORY (distance between grid or centre of rotation, with shakeout axis and corresponding angle) with respect to the mold axes / references. These dimensions must be CIRCLED (for the angles) and SQUARED (for linear dimensions) highlighted and clearly legible. Always indicate the centre of rotation of the figure. The above indications must be given on the main CROSS-SECTION drawing. EXAMPLE CROSS-SECTION A-A
FIGURE CENTRE OF ROTATION
INJECTION MOLD AXIS
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IMPORTANT: Always indicate grids and mold axes on all drawings (mold design drawings), and related written references. When necessary, indicate various shakeout axes with corresponding angle, include the following boxed note to the side of the dimension (degrees): EXAMPLE
FIRST ROTATION
SECOND ROTATION
THIRD ROTATION
Always mark MANDATORY on drawings (plan and cross-sections) the positions and dimensions of reference pins on die and punch for executing the starting points for cutting and machining Mold Path starting points. The dimensions of pin positions must be inserted in rectangular boxes, highlighted and clearly legible. Indicate the pin seat on the drawing with the note: REFERENCE PIN. EXAMPLE CROSS-
SECTION A-A
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On perimeter profiles, where possible execute the out of figure at 15 mm constant radius as shown in the EXAMPLE
SH
AK
EO
UT
AX
IS
For molds for elements with profiles coupled with other parts (e.g. knurled dashboard), thus subject to elongation or shortening, if possible execute out of figure as shown below in the EXAMPLE
SH
AK
EO
UT
AX
IS
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In setting up the mold highlight the missing or critical rakes above all in relation to the type of knurling (photo incision). We recommend rake angles always oversized by circa 2° with respect to the requirements of knurler / customer. EXAMPLE
TOO NEAR
For larger molds, such as those for rear fenders with deep side fins, provide seats for bracketing the piece to the cutter as shown in the EXAMPLE
PUNCH DIE
N.B.= This operation must be agreed with Tech. Office and Production before implementation. RECOMMENDED SPHERICAL CUTTERS: R.20 - R.16 - R.12,5 - R.10 - R.8 - R.6 - R.4 - R.3 - R.2 RECOMMENDED TORIC CUTTERS: R.18 - R.12,5 (with R.0.5 insert on bottom) R.10 (with R.1.6 insert on bottom) R.8 (with R.1.3 insert on bottom) R.6 (with R.1 insert on bottom) R.37,5 - R.26 - R.20 (with R.6 insert on bottom) R.40 (with R.8 insert on bottom) N.B. The drawn representations of radii for working out of figure, seats of moving parts, inserted fixed blocks and other Numerical Control processes, must be as per Customer technical specifications and agreed with TAG.
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For larger molds, such as those for rear fenders with deep side fins), evaluate the need to adopt an inserted type central punch block according to the mechanical and copying processes. In calculating the shakeout of the undercuts always take account of the shrink factor. In the mold set-up phase, highlight the out of figure zones to reject, since not indispensable for mold closure. (To be agreed with TAG). All inserted fixed blocks for ribbing, daters, markings, various captions, T hinges, must be fixed from figure side in order to be removed from press if necessary. (To be agreed with TAG). On inserted blocks for deep ribbing always assure perfect polish executed in the direction of part shakeout, and provide vents and calibrations. Fit bocks in HA ELMEDUR (or equivalent material) for zones difficult to condition, to be agreed with the TAG manager. Fit tempered inserted blocks (where required) on mold positioning points, which are indispensable on the heels of carriages to permit adjustments, with lubrication channels. The length of the mold guide columns must be such that the columns engage the opposite part (punch/die) when between at the maximum points between punch and die there is a clearance of > 20 mm. Fit extensions in case of excessive overhang. Avoid pointed fitting zones, crests of steel, weak coupling surfaces. When setting up the mold, or better during the product feasibility phase, it is very important to verify the kinds of problems that could be encountered in building the mold, identify any electrodes, zones of difficult access for milling and copying, any undercuts that require complex movements, suitable injection points, mold divisions with minimum inclination, to eventually improve solution performance both of the mold and production. Where the mold requires figure divisions with rakes less than 5°, fit positioning plates in the mold at 1° to prevent these zones from colliding when closing the mold.
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MOLD PLATES POSITIONING DIAGRAM Operator side view of mold in press
MOVING SIDE FIXED SIDE
PUNCH DIE
MICRO P.E CIRCUIT D.
COOLING CIRCUIT DIAGRAM
HYDRAULIC C.D
PNEUMATIC CIRCUIT DIAGRAM
CIRCUIT DIAGRAM
MICRO
HYDRAULIC C.D
HOT RUNNER DIAGRAM
ELECTRICAL CONNECTIONS
COOLING CIRCUIT DIAGRAM
PNEUMATIC CIRCUIT DIAGRAM INJECTION
The plates can be in plastic coated paper form (standard) or in aluminum and screen printed (if specifically required by customer). All plates must be clearly visible by the operator and must be dimensionally standardized according to the class of mold: For class 1 molds = according to available area; For class 2 molds = 100 x 100; For class 3 molds = 100 x 200.
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DRAWINGS AND TOLERANCES Drawings must conform to UNI standards (base system H8) The system adopted for dimensioning is starting point from mold axis. Always indicate on drawings the dimensions necessary for starting the figure with respect to the mold axis (see Chap.3 Pg.3 of 21) Indicate on drawings the position and dimensions of the starting pins both on punch and on die (see Chap.3 Pg.4 of 21) Include the following note in the title box of each individual drawing: Dimensions without tolerance indications as per Table ISO 2768-m Said table lists the allowed deviation limits for: Linear dimensions Linear dimensions of bevels, connections Angular dimensions For our type of equipment the tolerance class used is: Mean designation For other tolerances, machining marks, etc., see attached examples. TABLE AS PER ISO 2768 - m Values in mm
Tolerance class Deviation limit for nominal dimensions ranges
Desig- nation
Denomi- nation
fr. 0.51) to 3
over 3 to 6
over 6 to 30
over30 to 120
over 120 to 400
over 400 to 1000
over 1000 to 2000
over 2000 to 4000
f fine ± 0.05 ± 0.05 ± 0.1 ± 0.15 ± 0.2 ± 0.3 ± 0.5 --
m medium ± 0.1 ± 0.1 ± 0.2 ± 0.3 ± 0.5 ± 0.3 ± 1.2 ± 2
c coarse ± 0.2 ± 0.3 ± 0.5 ± 0.3 ± 1.2 ± 2 ± 3 ± 4
v v. coarse -- ± 0.5 ± 1 ± 1.5 ± 2.5 ± 4 ± 5 ± 6
1) For nominal dimensions less than 0.5 mm, deviation must be indicated after the nominal dimension
National note – the table is also valid for internal connections Table II – Admissible deviation limits for linear dimensions and connections
to eliminate sharp edges (for external connections and bevel heights) Values in mm
Tolerance class Deviation limit for nominal dimensional ranges
Designation Denomination fr. 0. 51) to 3
over 3 to 6 over 6
f fine
m medium ± 0.2 ± 0.5 ± 1
c course
v v.coars ± 0.4 ± 1 ± 2
1) For nominal dimensions less than 0.5 mm, deviation must be indicated after the nominal dimension
Table III – Deviation limit for angular dimensions
Tolerance class Deviation limit according to length ranges,
in millimeters, with shortest side of corner considered
Designation Denomination to 10 over 10
to 50 over 50 to 120
over 120 to 400
over 400
f fine
m medium ± 1 ± 0°30’ ± 0°20’ ± 0°10’ ± 0°5’
c course ± 1°30’ ± 0°10’
v v.coars
± 3 ± 2 ± 1° ± 0°30’ ± 0°20’
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TOLERANCES AND MACHINING MARKS ON MOLD EXAMPLE 1
Screw max M16
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EXAMPLE 2
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EXAMPLE 3 SEC. A-A SEC. B-B VIEW C
Housing detail
BEVEL/RADIUS BEVEL
RADIUS
DETAIL D
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TITLE BOX
- All drawing sheet must have a title box to the lower right. - The title box must be completed in full from the beginning, in the first issue. - The vertical lines to the right must be filled in each time a modification is made. The criterion for compilation is as follows: indicate the modification (M1) the impact (addition of ribbing block), the modification date (25-02-04) and the draftsman. - Fill in the lines concerning the modification only on the drawing the modification has been effectively introduced.
MOLD TECHNICAL NOTES On Dwg. I / fg.A (Punch plan view) of the project, above the title box, include the mold technical notes table . EXAMPLE
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STAMP FOR PARTS Each individual part, in addition to the tolerances and roughness/machine marks must have the stamp positioned to the right of the drawing, giving the part N°, the construction material and heat treatment, quantity of parts to construct and the drawing number. . EXAMPLE
Quantity 1
Part N° 115
Drawing N° 115
Material and treatment 16NiCr11 UNI 8550
Casehardened and tempered HB = 578-650
carriage positioning plate
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DRAWING NUMBERING The following table lists the standard drawing numbering system to adopt for each project. NOTE: the list of drawings below must be adapted to each specific project, eliminating and/or addition drawings and maintaining sequential numbering.
DWG.N°1 DWG.N°1 DWG.N°1 DWG.N°1 DWG.N°1 DWG.N°1 DWG.N°1 DWG.N°1 DWG.N°1
Assembly plan view - punch side Assembly plan view – die side Assembly cross-section A-A Assembly longitudinal section B-B Assembly cross-section C-C Assembly cross-section D-D Assembly misc. partial cross-sections Assembly Head and Long. View
DIE PUNCH PUNCH CARRIER MOVING TRESTLE FIXED TRESTLE EJECTOR PLATE HOT RUNNER MISC. PARTS (carriages, blocks,) CUT LATHED MISC. DIAGRAMS PLATES
ASSEMBLIES DWG.N° 1 Sheet A, B, C
EXAMPLE
PARTS
DWG.N°2 DWG.N°3 DWG.N°4 DWG.N°5 DWG.N°6 DWG.N°7 DWG.N°8 DWG.N°9 DWG.N°10 DWG.N°11 DWG.N°12 DWG.N°13
Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;…. Sheet A, B, C;….
Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…Sheet A, B, C;…
Drawing format shall be as per UNI 923-924 the following pages list the format of drawings and the methods for trimming copies. Always square work sheet as per attached formats. Non-format squaring is not acceptable for any reason. When possible, render drawings in scale 1:1.
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DRAWING FORMATS AND FOLDING
PAPER AND DRAWING FORMATS
NORMAL PAPER AND DRAWING FORMATS (Std. UNI 923-924) Paper formats have been internationally unified into a range offundamental sizes (A series), in which each size is the result of doublingthe previous one, while the ratio between the sides is always 1: ? 2.The base format (A0) has an area of 1 m2. There are also theadditional B and C series, use of which is reserved to specialcartographic applications. From the normal formats listed in the table, elongated formats can beobtained by multiplying the shorter side by a preferably whole numberor a number that if necessary includes a net fraction ½ , ¼ , ¾ , .
TECHNICAL DRAWINGS (See. Std. UNI 938-940)
Arrangement of title box: for A4 format or larger drawings, the title and other information must be arranged in a box of 185 mm maximum width situated in the lower right corner of the sheet (see figure). Folding: Copies of drawings must be folded into A4 format as shown in the diagrams. Folding with leading edge is foreseen for collation into dossier or insertion into ring binders. In these cases, especially for large format drawings, the leading edge should be reinforced by gluing on a reinforcing strip.
Fundamental series Additional series
Symb. Symb. Symb. Dimensions Dimensions Dimensions
Folding with leading edge Folding without leading edge
Short edge Short edge
Shor
t edg
e
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ISSUE OF DRAWINGS TO PRODUCTION / CUSTOMER Denomination
INTERNAL TOOLS
EXTERNAL TOOLS
CUSTOMER
1st delivery
1 copy assemblies 1 copy parts
1 copy assemblies 1 copy parts
1 copy assemblies 1 copy parts
2nd delivery
1 copy assemblies 1 copy parts
1 copy assemblies 1 copy parts
1 copy assemblies 1 copy parts
3rd delivery 1 copy assemblies
1 copy assemblies 3 copies parts
1 copy assemblies 1 copy parts
1 copy assemblies 1 copy parts
ISSUE OF BILL OF MATERIALS 1ST DELIVERY N°1 COPY FOR MAJOR STEELS 2ND DELIVERY N°1 COPY FOR MAJOR PARTS (CARRIAGES, SLICES, ETC.) 3RD DELIVERY N°1 FINAL DESIGN COPY 100% COMPLETE
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CHAPTER 4
BILL OF MATERIALS THERMOPLASTIC INJECTION MOLDS
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BILL OF MATERIALS COMPILATION
When compiling the bill of materials, proceed as follows: Parts to order in advance: These parts shall be attributed a number between 1 and 99 preceded by 0/ , example: 0/1 . . . . . . . . .0/99. “Shot-peened” parts: The numbering of these parts starts from n°100, following the intervals given below: from 100 to 299 for constructed parts from 300 onwards for commercially available parts Each part must maintain the original numbering. This is also valid for parts ordered in advance, on drawings marked “shot-peened” as per the BILL OF MATERIALS. If a part is cancelled, it must still appear on the updated BILL OF MATERIALS, barred, with “PART CANCELLED” written on the corresponding line. The number of a cancelled part must not be attributed to any other part.
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For welded parts consisting of several pieces, indicate: A) the part number B) the part dimensions and material C) note: welded, see drawing D) Quantity EXAMPLE
Part Name Finished dimensions MAT. Q.TY
BRACKET
BRACKET
BRACKET
Finished dimensions 40x180x300 welded See drawing
Finished dimensions 40x80x60 welded See drawing
Finished dimensions 25x180x80 welded See drawing
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As regards the conditioning fountains, the shot-peening system and the Bill of materials: EXAMPLE
Part Name Finished dimensions MAT. Q.TY
ROD See drawing
ROD
ROD
BAR
BAR
BAR
See drawing
See drawing
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Moreover, in the drawing of the part, a recognition table must be created for the fountains, including measurements, quantities and mounting references for the fountain itself, indication which are the Die fountains and which are the Punch fountains. EXAMPLE
FOUNTAIN DIM A DIM B Q.ty
Plug ¾ gas conn.
Braze Braze
Bar Fe 430
PUNCH
rod
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CHAPTER 5
Design methods Mounting assemblies ( under preparation )
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CHAPTER 6
Standard – commercial parts ( under preparation )
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CHAPTER 7
MOLD AND INJECTION SYSTEM RHEOLOGY
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INJECTION The geometry and technology of the injection system and, in particular, the number and position of injection points, the geometry and dimensions of the feed channels, type of Hot Runner and corresponding sizing, must be agreed with the TAG. The mold manufacturer must in any case perform a complete analysis using specific Mold-Flow software. The degree of precision required of this analysis must be agreed with the TAG according to the Mold characteristics. The injection points and fittings must be positioned such as to meet the technical and appearance requirements of the part. Injection points are not allowed in positions that may compromise part appearance and/or function (e.g.: visible surfaces, contact faces for seals, etc.). The channels and any flow tunnels must conform the specifications subject to approval both by production and by Customer. Always check (very important) the filling balance. In the case of multiple figure molds, unbalance between the figures is not allowed. Later on there are some examples of application taken from practical experience. The use of the systems shown in these examples in no case exonerates the builder of the mold from responsibility for its correct function. EXAMPLES OF INJECTION SYSTEMS FILM INJECTION SIDE INJECTION
FAN OR FISHTAIL INJECTION TUNNEL INJECTION ON WALLS
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TUNNEL INJECTION ON
EJECTOR
CURVED OR CATS CLAW TUNNEL INJECTION
CAPILLARY INJECTION SPOKED INJECTION
TAB INJECTION
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EXAMPLES OF INJECTION CHANNELS A) CIRCULAR SECTION INJECTION CHANNEL ( IN PUNCH AND IN DIE)
B) CIRCULAR SECTION CHANNEL INJECTION CHANNEL (ONLY FROM DIE OR PUNCH SIDE)
C) TYPICAL SECTION INJECTION CHANNEL (ONLY FROM DIE OR PUNCH SIDE)
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EXAMPLES OF PLUG-RETAINER FOR INJECTION CHANNELS
Trapezoid
Drop or tab
Petal
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HOT RUNNERS The following are a number of examples, giving the project specifications for correctly design and building the hot runners . Basics: HEAT TREATMENTS TO USE SHOT-PEENING ELECTRICAL CIRCUIT DIAGRAM - PLATE MAPPING OF ZONES TO HEAT AND TO CHECK CONSTRUCTION TOLERANCES CONSTRUCTION MATERIALS FOR THE VARIOUS PARTS ASSEMBLY OF PARTS LIST OF COMMERCIAL PARTS (screws, clamps, pins, etc...) PLANT WIRING The adoption of the systems shown in these examples in no case exonerates the mold builder from responsibility for its correct function.
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EXAMPLE OF ASSEMBLY TO ATTACH WITH DOCUMENTATION:
TOOL AXIS
NO
ZZLE
2
NO
ZZLE
1
OPERATOR SIDE
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EXAMPLE OF BILL OF MATERIALS TO ATTACH WITH DOCUMENTATION: MOLDS BILL OF MATERIALS
Denomination Plastic injection mold
Element: FENDERS TYPE 188 M FRONT VAN VERS.
Injection bush
Spacer
Electrical box plate
Grub screw
Lower thrust plate
Switcher plug
Nozzle 1
Nozzle 2
Nozzle 3
Nozzle 4
Hot runner body RH side
Hot runner bodyLH side
Denomination Finished dimensions
Material and treatment
Customer
Dwg. N°
Code NEW DEL.
Part N°
Dwg.
Date
Qt.y
Updat
e
R.dA N°
Deliver date
Job N° sheet
Order numbe Supplie
Compiled: App:
Mod
ific
atio
n
MOLDS BILL OF MATERIALS Denomination
Plastic injection mold Element: FENDER TYPE 188 MY FRONT VAN VERS.
Finished dimensions
Material and treatment
customer
Dwg. N°
Code New del.
Part. N°
Dwg.
Date:
Updat
e
R.d.A N°
Job N° Sheet
N° Supplie
Compiled App:
Delivery date
Order Denomination Qt.y
Hot runner body, central
Centering plate
Nozzle 5
Bush thrust plate Spacer
“U” profile Th. 2 mm Thrust plate
Mod
ific
atio
n
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CHAPTER 8
MOLD CONDITIONING THERMOSTATIC CIRCUITS MOLD COOLING
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MOLD CONDITIONING All water circuits for Punch, Die, Moving Parts, etc., must be suitable for controlling the temperature of the Mold in relation to the material being molded, the production cycle/times required by Customer and the critical zones of the figure. On large molds (Fenders, Dashboard, etc.) the average distance between one hole and the next must be circa 80-100 mm and the average distance from the figure tangent of circa 30-35 mm (minimum distance permitted by figure 10 mm). On medium sized molds (grills, ribbing, conduits, etc.) the average distance between one hole and the next must be circa 60-80 mm and the average distance from figure tangent of circa 25-30 mm (minimum distance permitted by figure 10 mm). The connector holes must be cut away from zones where critical cracks may occur, or tensions that could cause failures) for example near to the radii of positioning points or near to divisions under pressure. Assure a minimum flow rate of 10 lt/min at a pressure of 15 Atm. Use the fountains only where strictly necessary, always avoid water traps.
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In designing cooling circuits always indicate the length of each hole, the hole number and the circulation, and whether it is an Input or Output hole, on each project drawing illustrating the circuit, following the lines below: Hole 6, Fountain 1, Circuit 1, Output 1
NO!! CONNECTOR HOLES AT
CRITICAL POINTS AND NEAR TO POSITIONING
POINTS
NO TRAPPED WATER
OK CONNECTOR
FOUNTAIN 1
EXIT 1
Hole and thread diameters for tapered gas connectors on Tools
1) Ø 15 hole – with 3/8 G.con – Ø 22 fountain – with ¾ G.con
2) Ø 11 hole – with ¼ G.con – Ø 18 fountain – with ½ G.con
3) Ø 8 hole – with 1/8 G.con – Ø 15 fountain – with 3/8 G.con
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O-RINGS FOR CONDITIONING HOLES When it is necessary to by-pass the cooling circuit from one block to another block, use O-rings to assure hermetic circuit seal. The O-rings may differ according to the diameter of the holes used. List of O-rings according to hole: 1) Ø8 hole OR 3056 Nr.ANGST+PFISTER 2) Ø11 hole OR 3068 Nr.ANGST+PFISTER 3) Ø15 hole OR 128 Nr.ANGST+PFISTER 4) Ø22 hole OR 3112 Nr.ANGST+PFISTER Other OR used in the case of SHAFTS are OR 3100 (Ø30), OR 3118 (Ø35), OR 3137 (Ø40) and lastly OR 147 (Ø50). EXAMPLES
OR for HOLES
ALSO VALID FOR Ø 6 holes
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DRILLING PROF /ADMISSIBLE ANGLES AND TEMPERATURES TABLE
DRILLING WITH ANGLE 0°
DRILLING WITH ANGLE FROM 1° to 15°
DRILLING WITH ANGLE FROM 15° to 30°
Hole Depth
Hole Depth
Hole Depth
Hole Depth
DRILLING WITH ANGLE FROM 30° to 45°
INJECTED MATERIAL RECOMMENDED °C FOR TOOL MAX MOLTEN °C
If these materials are filled with glass fiber, add approx. 10/20° to the values given above
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General specifications for thermoplastic molds 2.0 17/10/2005
QUICK CONNECTOR SYSTEMS FOR CONDITIONING INPUTS-OUTPUTS EXAMPLE 1
Basic type with JIFFY MATIC – DME connectors
ONLY IF REQUIRED BY CUSTOMER
ONLY IF REQUIRED BY CUSTOMER
Externally bridge (if internal tool connection is not foreseen) with 3/8” male rubber hose connector plus PVC pipe with pipe clamp.
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EXAMPLE 2 PUSH LOK type system and delivery to general distributor
INPUT/OUTPUT DIAGRAM TOOL
TOOL DISTRIBUTOR
Externally bridge (if internal tool connection is not foreseen) with 3/8” male rubber hose connector plus PVC pipe with pipe clamp. If necessary, insert a flow regulator valve on outputs
OUTPUT DIAGRAM WITH VALVE TOOL
TOOL
DISTRIBUTOR
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EXAMPLE 3 PUSH LOK type system and delivery to general distributor
With the same system of connectors, it is possible to directly reach the tool edge in a distributor that brings together all the Inputs and Outputs of the various moving parts with delivery and return via columns inclined on Expeller Plates. The system shown here is the ¼ type for Ø 6 water holes, normally used for columns inclined by Ø 30/35, in the case that the columns are larger (slice guide columns) and water passage dimensions more ample, use the 3/8 type previously illustrated as Tool I/O system.
ZONE TO RE-CUT TO FACILITATE WATER PASSAGE
BLACK
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CHAPTER 9
HYDRAULIC CYLINDERS EXPULSION
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HYDRAULIC CYLINDERS In the absence of special Customer requirements or specifications, the following cylinders shall be used: DEMA Series TS maximum working pressure = 300 Kg/cm2
Where possible position the cylinders on the mold sides /heads) or mold lower sides. Avoid positioning them on the mold upper side (oil leakage problems in figure). Cylinders operating plungers and/or carriages shall be arranged to assure perfect function, both in terms of movement and stability. Always use cylinders with VITON seals. Moving plungers subject to return thrust must be hydraulically or mechanically damped. A cylinder must be represented in each project, indentified by, in addition to recognition code and technical specifications, the thrust or traction load of the cylinder itself. The hydraulic system must be made with “PARKER” flexible connectors and pipes, adequate for the required characteristics and working pressures. General Input and Output connections, positioned on the MOLD LOWER SIDE OPPOSITE OPERATOR (alternatively mold lower side), use Nippli male-male 1/2 G.con. Type: Parker 8HMK4. Minimum spacing between Output and Input 70 mm, with maneuverability clearance of 50 mm, see EXAMPLE
SECTION A-A
TOOL
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Where possible make bracketing plates sufficiently large to contain the cylinders mounted around the mold perimeter. If this is not possible, the mold must be fitted with guards or spacers to protect the cylinders. In building the hydraulic system, at the design stage, consider clearance for fitting connectors and pipes, as well as minimum curve radii of both flexible and rigid piping. All cylinders must be fitted with limit switches at both ends. Lastly, all hydraulic circuits must be tested and verified for seal and sequence prior to delivery to the test and/or production establishment.
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EXPULSION Expulsion refers to the part of the mold consisting of the trestle, expeller plates, expellers and parts associated with these groups. The expellers are subdivided into basic type (cylindrical, standard) and Pavè type expellers. In general basic expellers are used, positioned in figure in areas difficult to shakeout, steeply inclined walls, retained zones, perimeter flanges, and also according to conditioning. The diameters are determined by the spaces suitable for thrust and the molded material. Pavè expellers are used on walls that require very ample thrust areas and in some cases when the element to mold requires accompanying and support when being expelled. The diagram below graphically represents the method for positioning expellers and levelers, this definition applies to all punches, expeller plates and plates with expeller and leveler seats. The plan view of the punch or expeller plate must show the position of all expellers and levelers, , as well as the perimeter measurements of the mold, all expellers and levelers must be numbered. The positions must be dimensioned traditionally starting from the mold axes. In additional to traditional dimensioning, draft a summary table of the positions, numbering all expellers and levelers in a clockwise direction, indicating the coordinates (+/-X and +/-Y) as in the EXAMPLE
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CHAPTER 10
MISC. CALCULATIONS EYEBOLTS FOR LIFTING PRESSES
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LIFTING EYEBOLTS Each Molds must have eyebolts for lifting, of suitable capacity, to facilitate movements, lifting and mounting on the press . For Molds over 30 Tons, if not required by Customer, check the possibility of using own lifting gear . Molds with weight less than 30 tons must have their own eyebolts. All parts comprising the mold that exceed 20 kg must be equipped with threaded holes for lifting during manufacture and maintenance. Paint eyebolts or lifting rings and the transport harnesses in RAL 3001 red.. Each Mold must bear the plate COMAU STAMPI PLASTICA applied to Operator side. Punch the Ø of the eyebolt and the gauge near to the seat on the Mold. Punch the total weight of the mold on the Mold upper side near to the eyebolts and the weight of each half-mold at the centerline . All Molds must have 2 transport straps mounted diagonally, one Operator side toward the Mold upper side and one on the opposite side toward the Mold lower side. Check that it is possible to fit eyebolts or lifting rings on the Mold base plate to bracket it, whether for maintenance or for mold opening. Check that the eyebolts or lifting rings allow for balanced lifting of the complete Mold as well as for the two separate halves. Check that the eyebolts or lifting rings do not interfere with the press columns, gates and various linkages when mounting the Mold into presses, as well as with the pipes and electrical boxes aboard the mold. Check that the eyebolts or lifting rings can be mounted at least from two opposite sides of the Mold, plates, blocks, die and punch.
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EXAMPLE DIN 580 Eyebolts or lifting rings
Straight pull 45° pulll
DIN 580 EYEBOLTS Designation Geometry Max load
Allowed * (N) Weight (kg)
ID N°
For straight pull
For 45° pull **
MATERIAL C15 UNI 5331 SAFETY COEFFICIENT * = VALUE VALID FOR FULLY SCREWED-IN EYEBOLTS ** = VALUE REFERRED TO A PAIR OF EYEBOLTS
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EXAMPLE LAT Eyebolts or lifting rings
LAT EYEBOLTS
Designation
Geometry
Max load Allowed * (N) Weight
(kg)
ID N°
For straight pull
For 45° pull **
Key
N°
* = VALUE VALID FOR FULLY SCREWED-IN EYEBOLTS. ** = VALUE REFERRED TO A PAIR OF EYEBOLTS.
Tightening
torques
(Nm)
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PRESSES Presses for Mold test and/or sample pieces On drawings, always show all mold to press mounting instructions foreseen for the sampling test . Check and show: - SIDE CLEARANCE WITH GATES AND COLUMNS - PIECE EXPULSION (recommended for operator side) - "MOLD UPPER PART” - MOLD MOUNTABILITY FROM ABOVE PRESS - MOLD THICKNESS - MOLD DIAGONAL MEASUREMENTS (for rotation between columns and press plates) On mold construction drawings, show all centering rings of all foreseen presses. Indicate the diameter and type of press on the centering rings. Indicate the foreseen spherical radius on the injection bush. On mold construction drawings show the four columns of all foreseen presses. When knockout bars are foreseen, on mold constructions drawings show their positions with relative spacing and dimensions, and reference to the press . Production presses All the above conditions are also valid for production presses. Check two other critical points very carefully: - INPUT AND OUTPUT OF "ROBOT" OR MANIPULATOR (if foreseen) - WATER, OIL CONNECTIONS, ELECTRICAL SOCKETS (interfaces with press)
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