The achievable tolerances for parts produced through investment casting are established in an international norm: VDG P690. TCL produces castings according to this norm.
The tolerances specified below can be used as an indication, depending on the alloy and the part geometry
LINEAR TOLERANCES
General linear tolerances (in mm) according to VDG P690 D1
0-6 |
± 0.150 |
>6-10 |
±0.180 |
>10-18 |
± 0.220 |
>18-30 |
±0.260 |
>30-50 |
±0.400 |
>50-80 |
±0.450 |
>80-120 |
±0.550 |
>120-180 |
±0.800 |
>180-250 |
±1.200 |
>250-315 |
±1.300 |
>315-400 |
±1.800 |
>400-500 |
±2.000 |
FORM AND POSITION TOLERANCES
General form and position tolerances (in mm) according to VDG P690 D1
Nominal Dimension Range |
For Straightness / Flatness (mm) |
Roundness |
Parallelism/ Symmetry |
Coaxiallity |
0-6 |
0.15 |
0.20 |
0.25 |
0.30 |
>6-10 |
0.18 |
0.25 |
0.30 |
0.35 |
>10-18 |
0.25 |
0.40 |
0.40 |
0.50 |
>18-30 |
0.30 |
0.50 |
0.50 |
0.60 |
>30-50 |
0.40 |
0.60 |
0.70 |
0.80 |
>50-80 |
0.60 |
0.80 |
1.00 |
1.10 |
>80-120 |
0.80 |
1.00 |
1.30 |
1.30 |
>120-180 |
1.10 |
1.30 |
1.80 |
1.80 |
>180-250 |
1.50 |
1.80 |
2.50 |
2.40 |
>250-315 |
1.90 |
2.30 |
3.15 |
3.00 |
>315-400 |
2.40 |
2.90 |
3.80 |
3.80 |
>400-500 |
3.0 |
3.40 |
4.40 |
4.40 |
ANGLES
As cast tolerance of angels depends on their location in the casting. They range from ±0.5° for well supported positions to ±2° where inherent distortion could be expected. Inclusion of gussets and ribs often minimizes distortion and many sections can be mechanically straightened.
BLIND HOLES
Blind hole can be cast if length does not exceed the diameter.
SURFACE FINISH
Average Ra value generally ranges between 4.5 – 6.3 Ra.
From concept to finished drawing, TCL’s engineers are ready to assist customers at all stages of casting design. They can provide suggestions and guidance regarding tolerances and design details, alloy selection and even approximate pricing. Their aim is to help customers select the best manufacturing process, whether or not it is investment casting.
It is essential to ensure that all the details required to make an accurate feasibility study and cost estimation are specified.
The below list can be used as a guide for the information we require to prepare an accurate feasibility study and cost estimation:
- 2D Drawing
- Material Specification
- Heat treatment condition / Mechanical Properties
- Annual Quantity Requirement
- Part Weight
- 3D Model
- Application / Industry Sector
Steel Investment Castings/High Alloy Steel Investment Castings / Aluminum Investment Castings
TCL pours over 150 different alloys according to internationally accepted standards such as ASTM, DIN, JIS, IS and BS.
Our broad selection of alloys allow us to cater several industry sectors and meet their performance requirements.
MATERIAL SPECIFICATIONS
- CARBON STEEL
- ALLOY STEEL
- STAINLESS STEEL
- MARTENSITIC STAINLESS STEEL
- AUSTENITIC STAINLESS STEEL
- DUPLEX/SUPER DUPLEX STAINLESS STEEL
- PRECIPITATION HARDENING STEEL
- CAST IRON
- SG IRON (400 WITH 15% ELONGATION)
- PHOSPHOROUS BRONZE
- BRASS
- ALUMINIUM ALLOY
- COPPER ALLOY