Tolerances: Casting and Other Processes

Tolerances are affected by a number of factors including the process, the design and the material. Dean Group work to the international CT standard ISO 8062-3: 2007, with linear dimensional casting tolerances (DCT) ranging from DCTG 4 to DCTG 12.

All our manufactured parts are covered by the CT standard ISO 8062-3: 2007 and our processes generally fall between the tolerance bands DCTG 3 and DCTG 10. The achievable tolerances vary from process to process and always depend on design complexity and material specification involved. MIM, pressure die casting and premium grade investment casting are the most accurate processes involving the tightest tolerances.

Tolerances may vary depending on the process, design, material etc.

The achievable tolerances vary from process to process and always depend on design complexity and material specification involved.

We have included linear dimentional tolerances for dimensional casting tolerance grade (DCTG) for our processes below (please select the relevant tab):

  • Investment casting – premium grade
  • Investment casting – commercial grade
  • Die casting
  • Forging
  • Metal injection moulding (MIM) – please contact us for details

For the full list and other type of tolerances please see the full CT standard ISO 8062-3:2007 (available from www.iso.org).

Linear dimensional tolerances applicable to our premium grade investment casting process. This tolerance table is to be used as a design guide only as each project will need to be reviewed individually.

Dimensions in mm

Nominal dimensions related to the moulded part Linear dimentional tolerance for dimensional casting tolerance grade (DCTG)
DCTG
4
DCTG
5
DCTG
6
DCTG
7
DCTG
8
DCTG
9
DCTG
10
DCTG
11
DCTG
12
? 10 0.26 0.36 0.52
> 10 ? 16 0.28 0.38 0.54
> 16 ? 25 0.3 0.42 0.58
> 25 ? 40 0.32 0.46 0.64
> 40 ? 63 0.5 0.7
> 63 ? 100 0.78 1.1
> 100 ? 160 1.2 1.8
> 160 ? 250 1.4 2 2.8
> 250 ? 400 2.2 3.2 4.4
> 400 ? 630 5 7 10

As the default conditions for the dimensions, the casting tolerance shall be symmetrically disposed with respect to the nominal dimension, i.e. with one half on the positive side and one half on the negative side.

For the full list and other type of tolerances please see the full CT standard ISO 8062-3:2007 (available from www.iso.org).

Linear dimensional tolerances applicable to our commercial grade investment casting process. This tolerance table is to be used as a design guide only as each project will need to be reviewed individually.

Dimensions in mm

Nominal dimensions related to the moulded part Linear dimentional tolerance for dimensional casting tolerance grade (DCTG)
DCTG 9
? 10 1.5
> 10 ? 16 1.6
> 16 ? 25 1.7
> 25 ? 40 1.8
> 40 ? 63 2
> 63 ? 100 2.2
> 100 ? 160 2.5
> 160 ? 250 2.8
> 250 ? 400 3.2
> 400 ? 630 3.6
> 630 ? 1000 4
> 1000 ? 1600 4.6
> 1600 ? 2500 5.4
> 2500 ? 4000 6.2
> 4000 ? 6300 7

As the default conditions for the dimensions, the casting tolerance shall be symmetrically disposed with respect to the nominal dimension, i.e. with one half on the positive side and one half on the negative side.

For the full list and other type of tolerances please see the full CT standard ISO 8062-3:2007 (available from www.iso.org).

Linear dimensional tolerances applicable to our die casting process. This tolerance table is to be used as a design guide only as each project will need to be reviewed individually.

Dimensions in mm

Nominal dimensions related to the moulded part Linear dimentional tolerance for dimensional casting tolerance grade (DCTG)
DCTG 5 DCTG 6 DCTG 7
? 10 0.36 0.52 0.74
> 10 ? 16 0.38 0.54 0.78
> 16 ? 25 0.42 0.58 0.82
> 25 ? 40 0.46 0.64 0.9
> 40 ? 63 0.5 0.7 1
> 63 ? 100 0.56 0.78 1.1
> 100 ? 160 0.62 0.88 1.2
> 160 ? 250 0.72 1 1.4
> 250 ? 400 0.78 1.1 1.6
> 400 ? 630 0.9 1.2 1.8
> 630 ? 1000 1 1.4 2
> 1000 ? 1600 1.1 1.6 2.2
> 1600 ? 2500 2.6

As the default conditions for the dimensions, the casting tolerance shall be symmetrically disposed with respect to the nominal dimension, i.e. with one half on the positive side and one half on the negative side.

For the full list and other type of tolerances please see the full CT standard ISO 8062-3:2007 (available from www.iso.org).

Linear dimensional tolerances applicable to our forging process. This tolerance table is to be used as a design guide only as each project will need to be reviewed individually.

Dimensions in mm

Nominal dimensions related to the moulded part Linear dimentional tolerance for dimensional casting tolerance grade (DCTG)
DCTG 6 DCTG 7
? 10 0.52 0.74
> 10 ? 16 0.54 0.78
> 16 ? 25 0.58 0.82
> 25 ? 40 0.64 0.9
> 40 ? 63 0.7 1
> 63 ? 100 0.78 1.1
> 100 ? 160 0.88 1.2
> 160 ? 250 1 1.4
> 250 ? 400 1.1 1.6
> 400 ? 630 1.2 1.8
> 630 ? 1000 1.4 2
> 1000 ? 1600 1.6 2.2
> 1600 ? 2500 2.6

As the default conditions for the dimensions, the casting tolerance shall be symmetrically disposed with respect to the nominal dimension, i.e. with one half on the positive side and one half on the negative side.

For the full list and other type of tolerances please see the full CT standard ISO 8062-3:2007 (available from www.iso.org).