Accuracy Standards

Futaba inspection criteria for die set are compliant with "JIS B 5031 Die sets for press dies-Accuracy and measuring method." Since our die sets are manufactured in compliance with more accurate internal standards, even high precision die can deliver full performance.

Parallelism between upper and lower surfaces of punch holder and die holder

Long side length of nominal dimension (a×b) Up to 100 100 or more and up to 200
Standard 0.008 0.008 per 100
Precision* 0.004 0.004 per 100
Long side length of nominal dimension(a×b) More than 200 and up to 300 More than 300 and up to 600 More than 600 and up to 1000
Standard 0.015 0.025 0.040
Precision* 0.010 0.015 0.025

Squareness between post and lower surface of die holder

・ Press fit post (guide type BO, RO, WO, RT and WT)
  Up to 0.02 per 100
・Removable post (other guide types than the above)
 Up to 0.01 per 100

Parallelism after assembly

Long side length of nominal dimension (a×b) Up to 100 100 or more and up to 200
Standard 0.012 0.012 per 100
Precision* 0.008  0.006 per 100
Long side length of nominal dimension (a×b) More than 200 and up to 300 More than 300 and up to 600 More than 600 and up to 1000
Standard 0.025 0.035 0.060
Precision* 0.020 0.025 0.040

Squareness of shank to the upper surface of punch holder

Product type Stud shank Flange shank
Tolerance Up to 0.01 per 50

Shank

・Diameter

-0.05  0
 
・Cylindricity
 0.05

Squareness of reference plane (steel die set, aluminum alloy die set)

Long side length of holder (A×B) Up to 300 More than 300 and up to 600 More than 600 and up to 1000
Tolerance 0.03 0.05 0.10

Deviation of reference plane of punch holder/die holder (steel die set, aluminum alloy die set)

 Up to 0.05 per 300

Holder external dimension

±0.5  (steel die set, aluminum alloy die set) 

Holder thickness

Long side length of holder (A×B) Up to 300 More than 300 and up to 600 More than 600 and up to 1000
Standard ±0.20 ±0.25 ±0.30
Precision* ±0.10 ±0.15 ±0.25

Holder surface roughness (arithmetic mean roughness Ra)

  Reference plane Upper and lower planes Other plane
Standard 3.2 3.2 6.3
Precision* 3.2 1.6 6.3

Post/bush hardness

 59-64HRC (post is quenched by high frequency )

Post straightness

Length Up to 150  More than 150 and up to 250 More than 250 and up to 300
Tolerance 1.5μm 2μm 3μm

Circularity/cylindricity of post

・Circularity
   2μm
・Cylindricity 
   3μm

Circularity/cylindricity of bush

Circularity

Bush inner diameter Tolerance
19~30 2μm
31~58 3μm
60~70 3μm

Cylindricity

Bush inner diameter Tolerance
19~30 2μm
31~58 3μm
60~70 5μm

Clearance of plain guide (Bush inner diameter) - (Post diameter)

Post diameter 19~25 27~32 36~38 40~56
Clearance 5±2μm 8±2μm 10±2μm 12±2μm

Preloaded amount of ball guide (Post diameter) + (Ball diameter) × 2 - (Bush inner diameter)

Post diameter 19~25 27・28 31~36 37・38 40~56
Preloaded amount 22±2μm 24±2μm 28±2μm 31±2μm 34±2μm

* "Precision" is applied to the following products.
  - Aluminum alloy die set
  - BM/RM/WM/RK/WK/RR/HS/HY in US series and PS series of steel die set
 In the case of the following products, "pecision" can be specified.
- BS/RS/WS/RY/WY in US series and PS series of steel die set.
 "Standard" is applied to the other die sets.