1.GENERAL

Deviations from the nominal dimension can not e avoided in the fabrication of plastics mouldings.

Dimensional deviations occurring in the production process may result from a number of causes:

a.     Dispersion in the results of the processing. This is dependent on:

·         Uniformity of the moulding material;

·         The machine setting;

·         The mould temperature;

·         Deformation of the mould under pressure.

b.    Condition of mould:

·         Manufacturing tolerances for the dimension of the mould

·         Wear on the mould;

·         Variations in the position of movable parts of the mould.

The tolerances in this standard are specified on the basis of the above considerations and a large number of measurements derived from practical applications.

2.   FIELD OF APPLICATION

The tolerances in this standard:

are applicable – to the dimensions of plastics mouldings produced from thermoplastic and thermosetting moulding materials by compression moulding, transfer mould, compression injection moulding or injection mould or injection moulding;

are not applicable – to extrusions, blow-moulded or foamed mouldings, deep drawn parts, sintered parts and parts produces by a chip removal machining process. Table 1 gives the appropriate tolerance groups to be applied to the various moulding materials.

3. CONCEPTS

Moulding shrinkage VS

Moulding shrinkage means the difference between the dimensions of the mould  L_W  at (23±2)°C and those of the mouldingL_F, the letter having been stored for 16 hours after manufacture in standard atmosphere and then measured immediately after:

Radial moulding shrinkage VSR

The radial moulding shrinkage is the moulding shrinkage in the direction of injection.

Tangential moulding shrinkage VSR

The  tangential moulding shrinkage is the moulding shrinkage perpendicular to the  direction of injection.

Moulding shrinkage DVS

The moulding shrinkage difference is the difference between the radial and tangential moulding shrinkage

4.   Tolerances

The tolerances shall apply to mouldings at the time of acceptance; see clause 5.

Unless otherwise agreed, a reference must be made on the drawing to the acceptance conditions as specified in clause 5.

4.1. General tolerances [1]

The numbers specified in table 1, column 4, refer to the appropriate tolerance group in table 2.

If the deviations are not specified against the number for the dimension in production documents, order documents, ect. a note must be included referring to this standard, by specifying                            ALRI 00-01-750-2002 and the tolerance group given in table 2.

Example for specifying tolerance group 140:

DIMENSIONS WITHOUT TOLERANCE

See Norm

ALRI 00-01-750-2002 (140)

4.2. Deviations specified against dimensions [2]

In table 1, columns 5 and 6, two series are given for specifying tolerances against dimensions. The figures in these refer to the appropriate tolerance group in table 2. Series 1 tolerances can be complied with without special measures in production,

The series 1 and 2 tolerances shall be divided into upper and lower deviations in accordance with technical requirements.

Example showing division of tolerance 0,8 :

+ 0,8	or	0	or	± 0,4	or	+ 0,6	or	+ 0,3
0		– 0,8				–  0,2		–  0,5

Note:          If it is required that the tolerances be maintained in respect of effect acting on the moulding from the environment or caused by the condition of the moulding during the production process [3] , this shall be expressly  agreed between the supplier and the customer and specified in drawings, order documents, ect.

4.3. Dimensions related to the mould (see figure 1)

Dimensions in table 2 related the mould are in each case dimensions in the same part of the mould.

4.4. Dimensions not related to the mould (see figure 2)

Dimensions in table 2 not related to the mould are dimensions determined by the interaction of movable elements of the  mould, e.g. wall thickness dimensions and bottom by the shims or mould slides.

Note:          the tolerances on these dimensions are greater than those on the mould-related dimensions because the movable parts of the mould do not always reach the same final position when the mould is closed.

When the permissible deviations are entered against the dimension, take care to ensure that dimensions lying in the closing direction of the mould all vary in the same direction, i.e. that the bottom thickness for example increases when the overall height of the moulding increases.

For non-mould-related dimensions in the direction of closing of the mould, the values specified in table 2 can be increased if necessary in the case of compression moulding. In such a case the dimensions shall be marked with these increased tolerances.

4.5. Reduction of tolerances

For perpendicular dimensions tolerances narrower than those specified in table 2 may be obtainable by special measures.

For precision engineering at the present time the last two line in table 2 apply.

4.6. Drafts

Since all deviations apply to the nominal dimensions entered on the drawing, the drawing must clearly show the point on the draft taper to which the nominal dimension applies.

The size of the required draft tapers must be specified in the drawing.

4.7. Tolerances of and position

Deviations of form and position occurring alter removal from the mould are dependent on the shaper of the mould among other things.

Angular tolerances, tolerances of form and position shall be specified in accordance with DIN 7184 Part 1 directly against the dimension or (where applicable) as general tolerances in accordance with DIN 7168 Part 1 and Part 2.

Example showing method of specifying general tolerance:

Angular tolerances, tolerances of  form and position

DIN 7168 – mT

 

4.8. Tolerances of parts produced by chip removal marching processes

For parts produced by chip removal machining processes, DIN 7160, DIN 7161 and DIN 7172 Part apply.

4.9. Tolerances for threads

The following shall be used as a guideline: tolerance class “coarse” for metric threads, in accordance with DIN 13 Part 14 and tolerance class “B” for pipe threads in accordance with

DIN ISO 228 Part1.

5.   Acceptance conditions

Acceptance shall not take place earlier than 16 hours after manufacture of plastics moulding or after any required post-moulding treatment.

The atmosphere used for acceptance shall be standard atmosphere DIN 50014-23/50-2. For other temperatures and relative humidity’s the measured values must be corrected by taking into account the appropriate coefficients of linear expansions.

Post-moulding treatments (conditioning or hart treatment) shall be agreed between the supplier and the customer.

For plastic parts made of moulding materials for which the change in dimensions- e.g. through moisture absorption or re-crystallization – has to be taken into account in making the measures for acceptance, the type of between to supplier and the customer. It is advisable also to agree that the specified treatment conditions shall apply also to the measurement.

[1] Formerly designed as: “Dimensions without specified tolerance”

[2] Formerly designed as: “Dimensions with specified tolerance”

[3] These could be for example, temperature, atmospheric humidity, gases and vapours, liquids

[4] In the case of unreinforced, partly crystalline, non-hardening moulding materials (thermoplastics) the next highest tolerance group shall apply for wall thicknesses over 4 mm

[5] See page 8

TABLE 1 – CORRELATION OF TOLERANCE GROUPS WITH MOULDING MATERIALS

1	2			3	4	5	6
Symbol for basic material	Mouldings made from			Moulding materials in accordance with DIN	Tolerance  group
					For general tolerances	For dimensions where the deviations are indicates against the dimensions
						Series 1	Series 2
EP	Epoxy resin moulding materials				130	120	110
EVA	Ethylene vinyle acetate copolymer moulding materials			16778         Part 1	140	130	120
PF	Phenolic plastic moulding materials	Whit inorganic fillers	Type: 11.5-12-13-13.5-13.9-15-16	7708 part 2	130	120	110
		Whit organic fillers	Type: 30.5-31-31.5-31.9-32-51-51.5-51.9-52-52.9-71-74-75-83-84		140	130	120
UF MF	Aminoplastic moulding materials and Aminoplastic / Phenolic plastic moulding materials	Whit organic fillers	Type: 131-131.5-150-152-152.7-153-154-180-181-181.5	7708 part 3	140	130	120
		Whit inorganic fillers	Type: 155-156-158		130	120	110
		Whit organic and inorganic fillers	Type: 157-182-183		140	130	120
UP	Polyester resin moulding materials		Type: 801-802-803-804	16911	130	120	110
UP	Polyester resin mats		Type: 830-830.5-831-831.5-832-832.5-833-833.5	16913         Part 3	140	130	120
	Compounds for cold moulding		Type: 212-214	7708 Part 4	140	130	120
ASA	Moulding materials based on acrylonitrile-styrene acrylester copolymers				130	120	110
ABS	Moulding materials based on acrylonitrile-styrene acrylester copolymers			16772    Part 1	130	120	110

CA	Cellulose acetate moulding materials		7742      Part 1	140	130	120
CAB	Cellulose acetate butyrate moulding materials		7742      Part 1	140	130	120
CAP	Cellulose acetate propionate moulding materials			140	130	120
CP	Cellulose propionate moulding materials			140	130	120
PA	Polyamide moulding materials (amorphous, whit or without filler)			130	120	110
PA 6	Polyamide 6 [1] moulding materials (amorphous, whit or without filler)			140	130	120
PA 66	Polyamide 66 4moulding materials (amorphous, whit or without filler)			140	130	120
PA 610	Polyamide 610 4moulding materials (amorphous, whit or without filler)			140	130	120
PA 11	Polyamide 11 4moulding materials (amorphous, whit or without filler)			140	130	120
PA 12	Polyamide 12 4moulding materials (amorphous, whit or without filler)			140	130	120
	Glass fibre reinforced polyamide 6 – 66-610-11 and 12 moulding materials			130	120	110
PB	Polybutylene moulding materials			160	150	140
PBTP	Polybutylene terephthalate moulding materials	without filler		140	130	120
		with filler		130	120	110
PC	Polycarbonate moulding materials (whit filler, without filler)		7744      Part 1	130	120	110
PDAP	Polydiallyl phthalate moulding materials (with inorganic filler)			130	120	110
PE	Polyethylene moulding [2]  (without filler)		16776    Part 1	150	140	130
PESU	Polyether sulphone  moulding materials  (without filler)			130	120	110

PSU	Polysulphone moulding materials  (with filler, without filler)		130	120	110
PETP	Polybutylene terephthalate moulding materials (amorphous)		130	120	110
	Polybutylene terephthalate moulding materials (crystalline)		140	130	120
	Polybutylene terephthalate moulding materials (with filler)		130	120	110
PMMA	Polymethyl  methacrylate moulding materials	7745      Part 1	130	120	110
POM	Polyoxymethylene (polyacetal) moulding materials 5 (with filler), length of moulding < 150 mm		140	130	120
	Polyoxymethylene (polyacetal) moulding materials 5(without filler), length of moulding  ≥ 150 mm		150	140	130
	Polyoxymethylene (polyacetal) moulding materials 5 (with filler)		130	120	110
PP	Polypropylene mould materials 5  (without filler)	16774             Part 1	150	140	130
	Polypropylene mould materials 5  (glass fibre reinforced, reinforced with talcum or asbestos fibre)		140	130	120
PP/EPDM	Mixture of polypropylene and rubber (without filler)		140	130	120
PPO	Polyphenylene  oxide  moulding materials		130	120	110
PPS	Polyphenylene  sulphide  moulding materials (with filler)		130	120	110
PS	Polystyrene moulding materials	7441             Part 1	130	120	110
PVC-U	Unplasticized polyvinyl chloride moulding materials	7448             Part 1	130	120	110
PVC-P	Plasticized polyvinyl chloride moulding materials	7449             Part 1	No data available at present
SAN	Styrene acrylonitrile moulding materials (with filler, without filler)	16775          Part 1	130	120	110
SB	Styrene butadiene  moulding materials	16771         Part 1	130	120	110

	Mixture of Polyphenylene oxide and polystyrene (with filler, without filler)			130	120	110
	Fluorinated polyethylene-polypropylene moulding materials			150	140	130
	Thermoplastic polyurethane	Products with 70 to 90 Sh A [1]		150	140	130
		Products with over 50 Sh D 6		140	130	120

[6] For Shore hardness tests A and D see DIN 53505
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TABLE 2 – GENERAL TOLERANCES AND TOLERANCES ON DIMENSIONS WHIT DEVIATIONS ETERED AGAINST THE DIMESION
Tolerance group from Table 1	Code Letter(1)	NOMINAL DIMENSION RANGE (in mm)
		over	0	1	3	6	10	15	22	30	40	53	70	90	120	160	200	250	315	400	500	630	800
		Up to	1	3	6	10	15	22	30	40	53	80	90	120	160	200	250	315	400	500	630	800	1000
General tolerances
160	A		± 0,28	± 0,30	± 0,33	± 0,37	± 0,42	± 0,49	± 0,57	± 0,66	± 0,78	± 0,94	± 1,15	± 1,40	± 1,80	± 2,20	± 2,70	± 3,30	± 4,10	± 5,10	± 6,30	± 7,90	± 10,00
	B		± 0,18	± 0,20	± 0,23	± 0,27	± 0,32	± 0,39	± 0,47	± 0,56	± 0,68	± 0,84	± 1,05	± 1,30	± 1,70	± 2,10	± 2,60	± 3,20	± 4,00	± 5,00	± 6,20	± 7,80	± 9,90
150	A		± 0,23	± 0,25	± 0,27	± 0,30	± 0,34	± 0,38	± 0,43	± 0,49	± 0,57	± 0,68	± 0,81	± 0,97	± 1,20	± 1,50	± 1,80	± 2,20	± 2,80	± 3,40	± 4,30	± 5,30	± 6,60
	B		± 0,13	± 0,15	± 0,17	± 0,20	± 0,24	± 0,28	± 0,33	± 0,39	± 0,47	± 0,58	± 0,71	± 0,87	± 1,10	± 1,40	± 1,70	± 2,10	± 2,70	± 3,30	± 4,20	± 5,20	± 6,50
140	A		± 0,20	± 0,21	± 0,22	± 0,24	± 0,27	± 0,30	± 0,34	± 0,38	± 0,43	± 0,50	± 0,60	± 0,70	± 0,85	± 1,05	± 1,25	± 1,55	± 1,90	± 2,30	± 2,90	± 3,60	± 4,50
	B		± 0,10	± 0,11	± 0,12	± 0,14	± 0,17	± 0,20	± 0,24	± 0,28	± 0,33	± 0,40	± 0,50	± 0,60	± 0,75	± 0,95	± 1,15	± 1,45	± 1,80	± 2,20	± 2,80	± 3,50	± 4,40
130	A		± 0,18	± 0,19	± 0,20	± 0,21	± 023	± 0,25	± 0,27	± 0,30	± 0,34	± 0,38	± 0,44	± 0,51	± 0,60	± 0,70	± 0,90	± 1,10	± 1,30	± 1,60	± 2,00	± 2,50	±  3,00
	B		± 0,08	± 0,09	± 0,10	± 0,11	± 0,13	± 0,15	± 0,17	± 0,20	± 0,24	± 0,28	± 0,34	± 0,41	± 0,50	± 0,60	± 0,80	± 1,00	± 1,20	± 1,50	± 1,90	± 2,40	±  2,90
Tolerances on dimensions with deviations entered against the dimension
160	A		0,56	0,60	0,66	0,74	0,84	0,98	1,14	1,32	1,56	1,88	2,30	2,80	3,60	4,40	5,40	6,60	8,20	10,20	12,50	15,80	20,00
	B		0,36	0,40	0,46	0,54	0,64	0,78	0,94	1,12	1,36	1,68	2,10	2,60	3,40	4,20	5,20	6,40	8,00	10,00	12,30	15,60	19,80
150	A		0,46	0,50	0,54	0,60	0,68	0,76	0,86	0,98	1,14	1,,36	1,62	1,94	2,40	3,00	3,60	4,40	5,60	6,80	8,60	10,60	13,20
	B		0,26	0,30	0,34	0,40	0,48	0,56	0,66	0,78	0,94	1,16	1,42	1,74	2,20	2,80	3,40	4,20	5,40	6,60	8,40	10,40	13,00
140	A		0,40	0,42	0,44	0,48	0,54	0,60	0,68	0,76	0,86	1,00	1,20	1,40	1,70	2,10	2,50	3,10	3,80	4,60	5,80	7,20	9,00
	B		0,20	0,22	0,24	0,28	0,34	0,40	0,48	0,56	0,66	0,80	1,00	1,20	1,50	1,90	2,30	2,90	3,60	4,40	5,60	7,00	8,80
130	A		0,36	0,38	0,40	0,42	0,46	0,50	0,54	0,60	0,68	0,76	0,88	1,02	1,20	1,50	1,80	2,20	2,60	3,20	3,90	4,90	6,00
	B		0,16	0,18	0,20	0,22	0,26	0,30	0,34	0,40	0,48	0,56	0,68	0,82	1,00	1,30	1,60	2,00	2,40	3,00	3,70	4,70	5,80
120	A		0,32	0,34	0,36	0,38	0,40	0,42	0,46	0,50	0,54	0,60	0,68	0,78	0,90	1,06	1,24	1,50	1,80	2,20	2,60	3,20	4,00
	B		0,12	0,14	0,16	0,18	0,20	0,22	0,26	0,30	0,34	0,40	0,48	0,58	0,70	0,86	1,04	1,30	1,60	2,00	2,40	3,00	3,80
110	A		0,18	0,20	0,22	0,24	0,26	0,28	0,30	0,32	0,36	0,40	0,44	0,50	0,58	0,68	0,80	0,96	1,16	1,40	1,70	2,10	2,60
	B		0,08	0,10	0,12	0,14	0,16	0,18	0,20	0,22	0,26	0,30	0,34	0,40	0,48	0,58	0,70	0,86	1,06	1,30	1,60	2,00	2,50
Precision engineering	A		0,10	0,12	0,14	0,16	0,20	0,22	0,24	0,26	0,28	0,31	0,35	0,40	0,50
	B		0,05	0,06	0,07	0,08	0,10	0,12	0,14	0,16	0,18	0,21	0,25	0,30	0,40
(1)           A = for non – mould –  related dimensions
B = for mould related dimensions

Está disponível para consulta um artigo de referência com a numeração e designação dos diferentes componentes de moldes para matérias plásticas.