David Ellis Co., inc. is a leader in the manufacture of metal hardness blocks, combining 125 years of experience in the maintenance, calibration and service of various types of durometers to produce all scale sizes of cloth, rockwell, Knoll and vickers blocks. David Ellis Co., inc. has passed NAVLP's ISO/IEC 17025:2005 laboratory certification, and all the hardness blocks meet the requirements of ASTM standard, international ISO standard and military standard, etc. They can be traced to NIST national metrology institute in the United States, and are now sold from stock.
The ASTM e-18 Rockell hardness block originally imported from the United States and an authoritative test report can be traced to the NIST national institute of measurement
ASTM e-18 rockwell hardness block specification table |
scale | head | load | The scope of | The material |
A Scale | C Diamond | 60 Kg | A60 - A84 | Steel |
A Scale | C Diamond | 60 Kg | A20 - A59 | Brass |
A Scale | A Diamond (Carbide) | 60 Kg | A88 & up | Carbide |
B Scale | 1/16" Ball | 100 Kg | B10 - B92 | Brass |
B Scale | 1/16" Ball | 100 Kg | B90 - B130 | Steel |
C Scale | C Diamond | 150 Kg | All | Steel |
D Scale | C Diamond | 100 Kg | All | Steel |
E Scale | 1/8" Ball | 100 Kg | All | Brass |
F Scale | 1/16" Ball | 60 Kg | All | Brass |
G Scale | 1/16" Ball | 150 Kg | G2.5 - G64 | Brass |
G Scale | 1/16" Ball | 150 Kg | G66 & up | Steel |
H Scale | 1/8" Ball | 60 Kg | All | Brass |
K Scale | 1/8" Ball | 150 Kg | All | Brass |
L Scale | 1/4" Ball | 60 Kg | All | Brass |
M Scale | 1/4" Ball | 100 Kg | All | Brass |
P Scale | 1/4" Ball | 150 Kg | All | Brass |
R Scale | 1/2" Ball | 60 Kg | All | Brass |
S Scale | 1/2" Ball | 100 Kg | All | Brass |
V Scale | 1/2" Ball | 150 Kg | All | Brass |
NOTE: Aluminum Test blocks are available in "B", "E", "F", "G", "H", "K" Scales, but ranges are more limited. |
ASTM e-18 surface rockwell hardness block specification table |
scale | head | load | The scope of | The material |
15N Scale | N Diamond | 15 Kg | All | Steel |
30N Scale | N Diamond | 30 Kg | All | Steel |
45N Scale | N Diamond | 45 Kg | All | Steel |
15T Scale | 1/16" Ball | 15 Kg | All | Brass |
30T Scale | 1/16" Ball | 30 Kg | All | Brass |
45T Scale | 1/16" Ball | 45 Kg | All | Brass |
15W Scale | 1/8" Ball | 15 Kg | All | Brass |
30W Scale | 1/8" Ball | 30 Kg | All | Brass |
45W Scale | 1/8" Ball | 45 Kg | All | Brass |
15X Scale | 1/4" Ball | 15 Kg | All | Brass |
30X Scale | 1/4" Ball | 30 Kg | All | Brass |
45X Scale | 1/4" Ball | 45 Kg | All | Brass |
15Y Scale | 1/2" Ball | 15 Kg | All | Brass |
30Y Scale | 1/2" Ball | 30 Kg | All | Brass |
45Y Scale | 1/2" Ball | 45 Kg | All | Brass |