DESIGN CRITERIAS:

*It is recommended to contact us to ensure that the dimensional details are healthier.

General Linear Tolerances
Linear tolerances
steels 1 steels 2 Al. Alloys 1 Al. Alloys 2
6 0,30 0,24 0,30 0,24
6-10 0,36 0,28 0,36 0,28
10-18 0,44 0,34 0,44 0,34
18-30 0,52 0,40 0,52 0,40
30-50 0,80 0,62 0,80 0,62
50-80 0,90 0,74 0,90 0,74
80-120 1,10 0,88 1,10 0,88
120-180 1,60 1,30 1,60 1,30
180-250 2,40 1,90 1,90 1,50
250-315 2,60 2,20 2,60 2,20
315-400 3,60 2,80 2,80 2,40
400-500 4,00 3,20 3,20 2,60
500-630 5,40 4,40 4,40 3,40
630-800 6,20 5,00 5,00 4,00
800-1000 7,20 5,60 4,60
1000-1250 6,60
Surface Roughness
steels Al.Alloys
CLA
(inch)
RA
(mm)
CLA
(inch)
RA
(mm)
N8 125 3,2 125 3,2
N9 250 6,3 250 6,3
Holes, blind holes and channels
open blind
2-4 ~ 1*d ~ 0,6*d
4-6 ~ 2*d ~ 1*d
6-10 ~ 3*d ~ 1,6*d
10 ~ 4*d ~ 2*d
Not: It is advised to use Standard Linear Tolerances for functional part dimensions

Special Linear Tolerances
Advised Techniques iflinear tolerances are required:
i ) Re-design the product with additional bars, brackets and gussets
ii) Adjusting wax injection wax to the nominal dimensions after the prototype
iii) Flatness and Straightness
iv) Jigging and manual straightening
v) Machining
vi) Other secondary treatments

Premium tolerance practicability should be checked for each diemension of each part.

Straightness-Flatness
Depending on the lenght, Parts can be casted straight and flat within 0.10 mm tolerance.
For thicker parts this tolerance can be up to 0.25 mm.

Roundness
Hole profile is within Standard Linear Tolerances. When required, Premium Linear Tolerances can be applied.
If possible, it is advisable to apply General Linear Tolerances.

Concentricity
The gap between the centers of two cylindrical surfaces -which are sharing a common point or an axis as their center-, is not more than the gap between their diameters multiplied by 0.10 mm.
If the height of a cylinder is more than two times of its diameter Straightness Tolerance should be added to eccentricity.

Angularity
As a standard rule, +/- 0.5 degrees or +/- 0.02 of the length is a normal tolerance for production.
For some cases, Angular Tolerance can go down to +/- 0.25 degrees or go up to +/- 1.0 degrees

Angularity
Nominal Dimensions Precision
1 2
Tolerance
Angularity(min) mm/100mm Açı(Dakika) mm/100mm
-30 mm 30 0,87 30 0,87
30 mm – 100 mm 30 0,87 20 0,57
100 mm – 200 mm 30 0,87 15 0,44
200 mm’den fazla 20 0,58 15 0,44

By using ceramic core, hole length can be increased to 30 x hole diameter.

Blind Holes 
Hole Length=Hole Diameter

Counterbores / Grooves 
Blind grooves can be casted up to 1.5 x width

Wall Thicknesses / Corner Radius (Radii) 
Minimum Wall thikness and Corner Radius depends on the configuration and the dimensions of the part. In some casts, it is possible to have 0.3mm Wall Thicknesses and R 0.3mm Corner Radius.

Surface Roughness 
Standart Surface Roughness in Investment casting is 125 RMS (Ra3.2-6.0). It is possible to improve Surface Roughness by using secondary methods and treatments.

Runners
For each section, one or more Runners with a thicker cross-section are used. After solidification, these Runners are removed by Grinding.

Internal Radii, Fillets
Internal radii and fillets improve the strength and integrity of the casting and minimise internal stresses. It is advisable to increase Internal Radii

Engraving 
Engraving should be raised letters on a recessed pad, so the top of engraving is below the surface of the part which is easier, more economical and without any defects.

Metallurgical and Visual Quality Requirements
Design, Material Type, Heat Treatment and Visual details should be discussed and decided between Customer and Cevik Technical Metallurgy.

Specific Requirements
All other requirements should be discussed and clarified together with our Technical Team before Order and Production


Dont hesitate to contact us about dimensions tolerances.