NDT DLH-330 Pen Type Hardness Testers

NDT DLH-330 Pen Type Hardness Testers


The DLH-330 is the new, improved version of the DLH-300

The DLH-330 is a pen type design, self-contained (Impact device display integrated) hardness tester, which means no cables and increased portability. It offers a  unique 1.77" large-screen OLED color display and is easy to operate with 4 soft keys above the screen achieve various functions. Interchangeable D impact device (standard) / DL impact device (optional) can be used for a dual purpose unit; it can also be used in restricted area measurements such as gear roots. Highly accurate (±6HLD) in any impact direction 360° and automatically identifies impact direction and gravity compensation.


  • Wireless pen type
  • Impact probe and display are fully integrated
  • 1.77” OLED color display
  • Replaceable batteries - instrument life is not limited by battery life
  • 1000 groups of tested data can be stored
  • Equipped with communication software
  • Optional DL & D type impact probes, dual purpose instrument.
  • DL type impact probe is efficient at testing:
    • Gear Roots
    • Confined Spaces


How Does It Work?

A spring in the probe projects the tungsten carbide ball tipped indenter at the test piece. Impact velocity is measured immediately prior to impact and then on rebound. The quotient is computed and displayed as the Leeb Hardness Value. On hard materials, the rebound velocity will be higher than that from softer materials, which will absorb more of the impact energy.

For a correct and repeatable measurement, certain conditions must be met:

  • The material must be smooth and free of paint, rust, oxide, etc.
  • The grain size of the test part must be small in relation to the indentation size.
  • The material cannot move or be deflected by the impact of the indenter.
  • Correction factor must be applied for the material's elastic modulus.
  • Correction for the effect of gravity must also be made.

Testing Parameters


The test piece surface needs preparation by filing, sanding or grinding. As a general rule, if you drag your thumbnail across the surface and it drags, the surface is too rough.

Grain Structure

Materials such as cast iron, that have a coarse (large) grain structure, will cause inconsistent measurements. The use of a much large indenter "G" probe will often correct for this condition.

Thickness & Mass

Test parts that have a low mass or thickness need to be supported to prevent movement or deflection.


Selection of the material corrects for material type. The following materials can be selected: Steel / Cast Steel, Gray Cast Iron, Nodular Cast Iron, Cast Aluminum, Brass, Bronze, Copper, Stainless Steel, Forged Steel and Tool Steel*

*Leeb measurements are affected by the material elasticity. To a large degree this is taken care of by selecting the most similar material type from the Material list. If you find that your measurements are a bit high or low, it is because the built-in correction factor does not match your material. You can try a different material to see if this gets you closer to a correct measurement. You can also use a known hardness sample of your test material (having enough mass and thickness) to determine the +/- error and then adjust the reading to match using the Calibration facility.

Probe Position

Set; Up, Down, Sideways, 45° up or 45° down

Technical Specifications

DLH-330 Specifications

Display 1.77 inch OLED with resolution 160*128 pixels
Hardness Scale HL, HB, HRB, HRC, HV, HS, Strength (σb)
Measuring Range HLD (200-960), HRC (19.8-68.5), HRB (13.5-100), HB (30-651), HV (80-976), HS (26.4-99.5), σb (375-2639)
Impact Devices D type impact device (Standard); Interchangeable DL type impact device (Optional)
Accuracy Measuring Error:±6HLD (HLD=800), Repeatability:±6HLD (HLD=800)
Measuring Direction
360 degree
Material Steel & Cast Steel, Stainless Steel, GC IRON, NC IRON, Cast Aluminum alloy, Copper-zinc alloy, Copper-tin alloy, Brass, Forged Steel, Alloy Tool Steel
Resolution 1HL, 1HV, 1HB, 0.1HRB, 0.1HRC, 0.1HS
Calibration Automatic
Language Multiple languages
Power Lithium battery (Capacity of 600 MA/H, voltage: 3.7 V) or Alkaline battery
Data Memory 1000 groups (each group includes 2-6 testing values and 1 average value)
Communication USB 2.0, Used for charging or data transfer
Software LMView software for transmission, storage and printing
Shut-off Auto off after 3 minutes of inactivity
Temperature -10℃~ +50℃
Net Weight 110g with Dtype impact device, 125g with DL type impact device

Kit Includes

  • Instrument
  • D Type Impact device
  • Test Block with HLD value
  • Small Supporting Ring
  • Charger
  • Cleaning Brush
  • Instruction Manual
  • Warranty Card
  • Certificate of Conformity
  • Instrument Case

Optional Accessories

  • DL Impact device
  • LmView Software
  • USB Communication Cable
Description Part # Saved Price Select Option Add to
DLH-330 Pen Type Hardness Tester HT-SY-DLH330 $1,050.00
DL Probe for the DLH-330 Hardness Tester HT-SY-DLH330-PROBE-DL $210.00