EMHT-20

Technical Specifications

Hardness Parameter	HL, HRC, HRB, HV, HB, HS
Measuring Range/ metallic materials	Table enclosed
Display Size	128 x 64mm LCD Screen
Display Functions	Hardness Scale, Hardness Value, Times, Average Indicator, Average Value Impact direction, Type of Impact Device connected, Memory Reference, Date, Time, Battery Power consumption.
Accuracy	Within 0.5% (HLD=800)
Statistics	Average Value
Memory	1250 groups
Output	RS 232 interface.
Impact Device	Sold with type D as Standard
Optional Impact Devices	DC/D+15G/C/E (see data sheet for Spec.)
Workpiece max. hardness value	940HV
Workpiece radius (convex/concave)	Rmin=50mm (with support ring Rmin=10mm)
Workpiece minimum weight	2Kg on solid support (0.1kg with couplant paste)
Workpiece min. thickness coupled	3mm (except with impact device G:10mm)
Workpiece min. case hardened depth	0.8mm
Indentation depth	see data sheet
Power	2 x AAA batteries 1.5V
Operating Temperature	5 to 50ºC (Impact device:120ºC max. briefly)
Overall Dimensions	108 x 62 x 25mm
Weight	180gr including impact device and printer

Standard Package	Optional Accessories

Main Unit	Special Impact Devices
Impact Device Type	UKAS certified Test Blocks in a range of hardnesses.
Testblock HLD-value	Support rings for convex-concave surfaces.
2 AAA Batteries	Mini-Printer and cable.
Cleaning Brush	Software and cable
Coupling Paste
Certificate of Cal.
Manual

IMPACT DEVICES FOR SPECIAL APPLICATIONS TM#

Impact devices:	D/DC/DL	D+15	C	G	E

Impact Energy:	11Nmm	11Nmm	3Nmm	90Nmm	11Nmm
Mass of Impact body:	5.5g	7.8g	3.0g	20g	5.5g
	DL: 7.3
Test Tip
Hardness	1600HV	1600HV	1600HV	1600HV	5000HV
Diameter	3mm	3mm	3mm	5mm	3mm
Material		Tungsten carbide			Diamond
Impact Body
Diameter	20mm	20mm	20mm	30mm	20mm
Length	147/86mm	162mm	141mm	254mm	155mm
Weight	75/50g	80g	75g	250g	80g
Max. Hardness of sample:	940HV	940HV	1000HV	650HB	1200HV
Preparation of surface;
Roughness class ISO	N7	N7	N5	N9	N7
Ax. Roughness depth Rt	10µm	10µm	2.5µm	30µm	10µm
Average roughness Ra	2µm	2µm	0.4µm	7µm	2µm
Min. Weight of sample
Compact shape	5kg	5kg	1.5kg	15kg	5kg
On solid support	2kg	2kg	0.5kg	5kg	3kg
Coupled on plate	0.1kg	0.1kg	0.02kg	0.5kg	0.1kg
Min. Thickness of sample
Coupled	3mm	3mm	1mm	10mm	3mm
Min thickness of hardened layers	0.8mm	0.8mm	0.2mm		0.8mm
Indentation of test tip With 300 HV
Diameter	0.54mm	0.54mm	0.38mm	1.03mm	0.54mm
Depth	24µm	24µm	12µm	53µm	24µm
With 600HV
Diameter	0.45mm	0.45mm	0.32mm	0.90mm	0.45mm
Depth	17µm	17µm	8µm	41µm	17µm
With 800HV
Diameter	0.35mm	0.35mm	0.305mm		0.35mm
Depth	10µm	10µm	7µm		10µm

Easy to Use Dynamic Metal Hardness Tester including external Probe and Calibration Block

Wide measurement range in Hi value. Direct display of converted values
Rockwell HRB . HRC . Vickers HV . Brinell HB . Shore HS
Quick , reliable and simple operation.
High Accuracy + or - 0.5%
Impact device which can be used at any angle, even upside down
Data Output RS232 and internal memory in a batch of 1250 average readings
For most metals
Date and time display
Lower and Upper limits setting with Low-High display
judge
Conforms to ASTM A956
Works on standard AAA batteries ; Auto-off power saver
after two minutes.
Optional Impact devices for specialist applications

Materials versus range for impact device D (HLD 200-900)
Material	HRC	HRB	HRA	HB	HV	HS

Steel and Cast Steel	20-68	60-100	59-86	80-650	80-940	32-100
Cold work tool Steel	20-68				80-940
Stainless Steel		46-100		80-650	80-800
Grey Cast Iron				90-380
Nodular Cast Iron				90-380
Cast Aluminium alloys				20-160
Brass		13-95		40-170
Bronze				60-290
Copper				45-315

The ranges are stipulated by the application limits of the relevant static procedure




Johnson & Allen Ltd. Neocol Works, Smithfield, Sheffield, S3 7AR Tel: Head Office: +44 (0) 114 273 8066 \| Fax: +44 (0) 114 272 9842 Tel: Scotland Office: +44 (0) 1506 882371 \| Fax: +44 (0) 1506 882371 Email: sales@johnsonandallen.co.uk