Measuring Principle
Dynamic Hardness Tester is an extremely light weight, portable, fast & reliable hardness tester based on a novel, dynamic & Rapid test procedure with widest measuring ranges for metals.
A carbide tipped shuttle with a definite kinetic energy is impacted on the specimen. A part of this energy absorbed by the specimen and is a function of the hardness of the specimen. A tubular device housing electrodynamic energy measuring device carries out the impacting of the shuttle. A measuring instrument receives the signal, equivalent to absorbed energy through a cable and displays with instant calculations. This displays Dynamic hardness (D) a three digit figure, which is proportional to the hardness of the specimen. The machine has built inconversion facility for given material to convert ‘D’ value to Vickers, Rockwell, Brinell scales which can be selected by pressing ▲▼keys.
Application
• In stores for Material identification.
• Measurement of Hardness in confined spaces.
• Variation in hardness over large work piece.
• Large & heavy components.
• Permanently installed parts.
• Surface hardened component or hardness on coatings.
Salient Features
• Sleek and handy design, comes in a slim briefcase, for carrying the machine.
• Alpha numeric display which indicates selected material & scale combination & hardness value.
• Average key to select average of 2 to 10 readings.
• Machine is having improved electronics with micro controller circuitry & user friendly software.
• 30 Hardness scales for different probes selectable by feather touch keys (PIs. ref. the table).
• Auto detection of probe facility is given.
• Automatic shut down facility is provided when machine is not in use for continously 10 minutes.
• This model operates on 2 numbers of pencil cells.
• Printing is possible with all types of ports i.e. Dot matrix (Centronic parallel port).
• Up to 100 readings can be stored in memory of the machine for printing purpose
(This facility is useful when operating the machine at site).
• Low test expenditure.
• Five numbers of probes can be given in different combinations. For eg. *Dl, D2, G1, G2 & C
*Dl, D2, D3, D4 & D5 . *Dl, D2, G1, SH &C
• Conversion of UTS facility is available on display by using side keys (◄). This is applicable for
only BHN scale for the range 226 to 634 BHN (hard steel & hard alloys only).
• Display last result (For eg. From Sr. No. 20 onward) facility is given by using upper arrow key (▲)
& down arrow key (▼). Also we can scroll through stored readings.
• The ON/OFF switch is provided with feather touch keyboard on front side.
• In this model both serial & printer interfaces are available on single port (serial interface is an extra accessory).
• Automatic calibration facility of probe is available through keyboard.
• Serial interface is possible with RS 232.
• Date entry & datewise printout facility is available.
• We can recall the readings one by one by using arrow keys (▼)(▲) on display, in display result mode.
Optional Features
1. Different types of probes are available
• Short (Suitable for checking hardness in holes, cylinders, etc.)
• Extended (Suitable for checking hardness in grooves, & recesses)
• Low Energy (Suitable for Surface Hardened Components, Coatings & Impact
Sensitive Components)
• Standard (Suitable for general application)
• Heavy (Suitable for Castings & Forgings)
2. Special conversion scales can be offered to suit different material.
3. Machine can be connected to computer for data loading
using our serial interface card which is an extra accessory.
Measuring Ranges
For Standard Probe (D) / Shot Probe (SH) / Extended Probe (EX) Scales( as follows )
Hardness
Material |
Test Range and Order Code |
Brinell |
Vickers |
Rockwell-C |
Rockwell-B |
|
|
| Steel and Cast Steel unalloyed / Low alloyed |
80-647 ST/BHN |
80-940 ST/ VPN |
20-68
ST/HRC |
38.4-99.5 ST/HRB |
32.5-99.5 ST/HSD |
| High Carbon, High Chromium (12% & above) Cold Work tool steel |
- |
80-898
HC/VPN |
20.4-67.1
HC/HRC |
- |
- |
| S. G. Iron ( CI with spheroided and nodular,graphite)(GG-40-80) |
131-387 SG/BHN |
- |
- |
- |
- |
| Grey Cast Iron Grade 15-40 (GG) |
93-334 Cl/BHN |
- |
- |
- |
- |
| Cast Al. Alloys non heat treated and quenched & tempered condition |
30-159
AL / BHN |
- |
- |
- |
- |
| Copper Zinc Alloys (Brass) |
40-1 73 BS/BHN |
- |
- |
13.5-95.3 BS/HRB |
- |
| Copper Al. and Copper Tin alloy (Bronze) |
60-290 BZ/BHN |
- |
- |
- |
- |
| Wrought Copper Alloys (Low alloyed) |
45-315 Cu/BHN |
- |
- |
- |
- |
| Stainless Steel &high temp. resistant Steel |
85-655 SS/BHN |
85-800 SS/VPN |
19.6-62.4
SS/HRC |
46.5-101.7 SS/HRB |
- |
For Heavy Probe (G) scales (as follows) -
|
Brinell |
Rockwell-B |
| Steel & cast steel/ Unalloyed and low allowed |
90-640 ST/BHN-G |
47-99
ST/HRB-G |
| Grey Cast Iron Grade 15-40 (GG) |
90-315
Cl/BHN-G |
- |
| S.G. Iron (Cl with spheroided and nodular graphite) (G.G.-40-80) |
125-350 SG/BHN-G
|
- |
For Low Energy Probe (c) scales (as follows) -
|
Brinell |
Vickers |
Rockwell-C |
ShoreD |
| Steel & Cast Steel/ Unallowed & Low Allowed |
80 - 683 ST/BHN-C |
80 - 996
ST/VPN - C |
20-69.5 ST/HRC-C |
31.9-99.6
ST/HSD-C |
DIMENSIONS
| Probes- |
Standard |
(D) |
- |
Dia. 25 x 150 mm |
| Short |
(SH) |
- |
Dia. 25 x 100 mm |
| Extended |
(EX) |
- |
Dia. 25 x 150mm |
| Heavy |
(G) |
- |
Dia. 30 x 255 mm long |
| Low energy |
(C) |
- |
Dia. 25 x 145 mm long |
Digital Display Unit - 188(L) X 105(W) X 64(H) mm
MEASURING ACCURACY
Average Measuring deviation +/-1% referred to D = 800 on 'D' scale standard test block at a particular test location.
OPERATING TEMPERATURE RANGE
0°C to 50°C
WEIGHT (Approx.)
Probe (standard) - 150 gms.
display Unit - 325 gms.
Standard Test block - 3000 gms.
Total Weightof Machine- 7 kg.
(with all accessories & carry case)
Field of Application
Field |
For D/SH/EX Probe |
For G Probe |
For C Probe |
Prepration of the surface to be tested
|
N7 (▼▼) |
N9 |
N5 |
| Max. roughness depth RL |
10 microns |
30 microns |
2.5 microns |
| Av. roughness depth Ra=Cla=AA |
2 microns |
7 microns |
0.4 microns |
Min. weight of the test piece
- of compact shape
- on solid support
- coupled |
5 KG
2.5 KG
0.1 - 2 KG |
15 KG
5-15 KG
0.5 - 5 KG |
1.5 KG
0.5 - 1.5 KG
0.02 -0.5 KG |
| Min. thickness of test piece coupled |
5 mm |
15 mm |
2 mm |
| Min. thickness of layer with surface hardening |
0.8 mm |
- |
0.2 mm |
Indentation of the test tip with 300 HB specimen hardness - Diameter
Depth
|
0.6 mm
13 micrones |
- |
- |
| Min. bore dia. of the specimen (only for short probe) |
100mm |
- |
- |
POWER SUPPLY CONDITIONS
Model: DHT- 6 - Dry cell batteries (1.5 VDC x 2 Nos.) Size - AA, Type R6.
STANDARD ACCESSORIES
• Probe (Normally 'D', if specified
other Probe can be supplied in place of ‘D) - 1 NO.
• Digital display unit - 1 NO.
• Standard test block calibrated in D Scale - 1 NO.
• Brush for cleaning probe - 1 NO.
• Carry case for Machine - 1 NO.
• Instruction manual - 1 NO.
• Coupling Jelly - 50 gms
EXTRA (OPTIONAL) ACCESSORIES
> StandardTest Block of any hardness
> Support rings Smaller radius for -
• (SR 1) Convex, Concave, Cylindrical, Spherical radius 30 to 60 mm
• (SR 2) Convex cylindrical radius 14.5 to 30 mm
• (SR 3) Convex cylindrical radius 10 to 15 mm
• (SR 4) Concave cylindrical radius 16.5 to 30 mm
• (SR 5) Concave cylindrical radius 12.5 to 17 mm
• (SR 6) Concave cylindrical radius 11 to 13 mm.
> Serial Interface (Windows 98 Based).
>
80 Col. Dot Matrix Printer.
> Different types of Probes -
1. Standard(D)
2. Short (SH)
3. Extended (EX)
4. Heavy (G)
5. Low Energy (C)
|
Model - DHT 6
