MULTI GRIT TESTER 508 Select
Multi-Blow Test Instruments for reproducible Test Results
Modular system with removeable bombardment attachment (VDA / SAE)
Optionally for VDA module: Attachment for tests in accordance with :
- PSA D24 1312
- Daimler DBL 5416
Purpose and Application
The MULTI GRIT TESTER 508 Select is a multi-blow test instrument, and its special feature is the good repeatability and comparability of the test results obtained.
The instrument is used to assess the ability of single and multiple layers of paints and similar coating materials to stand with the impacts caused by small bodies of low mass hitting the specimen at high speed as experienced on road and rail vehicles and other equipment used in the transport field.
Design and Mode of Operation
With the modular MULTI GRIT TESTER 508 Select, the user only needs a basic device which can be converted with little effort for bombardment tests "according to VDA" or "according to SAE".
The clear arranged menu navigation via the touch panel has password-protected levels, which protect against unauthorized access (such as program changes). Depending on the application, a VDA module (with manual or pneumatic specimen applying device) or a SAE module is selected. A change between the different modules designed as attachments is quick and easy, without spending lots of time.
Principle of the Test with VDA Module
The stone hammer blow tests according to VDA corresponds to the requirements of national and international standards.
The specimen is subjected to impacts by sharp-edged steel shot accelerated by compressed air.
An air accumulator in the system eliminates effects of momentary pressure variations in the external compressed air supply.
The shot is entered automatically using an adjustable vibratory feed.
To facilitate working, the VDA module is optionally available with a pneumatic specimen applying device.
Principle of the Test with SAE Module
In contrast to the VDA module, work is not carried out with steel shot, but usually with river gravel “water- eroded gravel”.
A defined number of impact bodies of specified properties is made to impinge for a given period of time and with a defined energy at a determinate angle of impact onto the specimen.
The bombardment of the test panels is carried out with determinate grit (according to ASTM D 3170) which is accelerated by compressed air.
Dependent of the specifications of further standards (mostly of car manufacturers) other shot materials can be used, too.
The shot is entered automatically using an adjustable vibratory feeding device.
An upstream compressed air reservoir compensates for fluctuations in the external compressed air network. The SAE module is equipped with a specimen holding device with an adjustable impact angle. The adjusting unit for the impact angle allows to adjust the orientation of the test panel relative to the direction of impact in the range from 30° to 90° in steps of 15°.
In contrast to the "VDA" version, the sample to be tested is located completely within the test room, during the whole bombardment process.
508 Select (VDA module)
DIN EN ISO 20567-1
FORD FLTM BI 157-06
RENAULT D24 1702
PSA D24 1312
DAIMLER DBL 5416
508 Select (SAE module)
- SAE J 400
- ASTM D 3170
Dimensions (W x D x H) :
Basic instrument approx. 1150 x 550 x 1350 mm
Net weight (approx.) :
Basic instrument approx. 125 kg
- VDA-Module-Select-M approx. 19 kg
- VDA-Module-Select-P approx. 22 kg
- SAE-Module-Select approx. 34 kg
Compressed air connection:
(VDA) min. 6 bar / max. 10 bar, requires connecting hose with ID 13 mm
(SAE) min. 8 bar / max. 10 bar, requires connecting hose with ID 19 mm Volume flow: min. 3 m3/min
Filling pressure control:
- approx. 5 bar (VDA),
- 7.8 bar overpressure (SAE),
automatic switching depending on the module
Working pressure: (0 - 6) bar / adjustable
Time for feeding shot: adjustable
Display: Touch Panel
Power supply: 85-264 VAC / 47-63 Hz (control circuit volt. 24 V)
Order Information 1
101-29040131 Stone Hammer Blow Instrument MULTI GRIT TESTER 508 Select Basic instrument with pressure vessel
101-29040431 Stone Hammer Blow Instrument MULTI GRIT TESTER 508 Select Basic instrument without pressure vessel
101-29060132 VDA-Module-Select-M with manual specimen applying device, 1 kg steel shot
101-29060232 VDA-Module-Select-P with pneumatic specimen applying device, 1 kg steel shot
101-29070132 SAE-Module-Select with adjusting unit for the impact angle , 1 kg shot (grit)
101-29630132 Equipment of basic instrument for operation at low temperatures up to -30 °C (climatic cabinet/cooling chamber)
101-30000132 Remote initiation with cable (6 m)
101-07060132 Attachment for tests in accordance with PSA D24 1312
101-17060132 Attachment for tests in accordance with Daimler DBL 5416
101-24080132 Impact Cabinet RIMpact II VDA
101-22710232 Impact Cabinet RIMpact I VDA
101-22710132 Impact Cabinet RIMpact I SAE
S p a r e P a r t s (for Model 508 Select VDA)
101-920002941 Steel shot (2.0 - 2.8 mm) GH-K-Diamant (acc. to Daimler DBL 5416) 1kg / 2 kg /5 kg / 10 kg
101-920002741 Steel Shot (3,55 – 5 mm) GH-K-Diamant, (acc. to VDA und DIN EN ISO 20567-1) 1kg / 5 kg / 10 kg
101-04860114 Accelerating Tube
S p a r e P a r t s (for Model 508 Select SAE)
101-920002841 Grit (shot) Gravel Shot acc. – (in acc. with SAE J400/ASTM D 3170) 1 kg / 5 kg / 10 kg
101-20860114 Accelerating Tube
Order Information 2
101-19990132 Set of Calibration Sandwiches for Model 508 VDA consists of: 10 calibration sandwiches 100 mm x 200 mm (each 1 x white cardboard with already preprinted legend form, carbon paper and clear PVC foil ~150 µm) and 1 plate of stainless steel (100 mm x 200 mm x 1 mm)
Please note, that the execution of the Calibration Sandwich differ a little bit from the recommendations of the EN ISO 20567-1:2006 (E) standard:
- - we use some white cardboard instead of the recommended white paper
- - we use some PVC foil (~150 µm) instead of the recommended PE foil (150 - 200 µm
)But, however, as you know we are since a lot of years the manufacturer of this kind of testing machine and the current specification of the Calibration Sandwich is a result of our long lasting experience in this field.
101-19990232 Set of Calibration Sandwiches for Model 508 SAE consists of: 10 calibration sandwiches 100 mm x 200 mm (each 1 x white cardboard with already preprinted legend form, carbon paper and clear PVC foil ~150 µm) and 1 plate of stainless steel (100 mm x 200 mm x 1 mm)
Please note, that the execution of the Calibration Sandwichdiffer a little bit from the recommendations of theEN ISO 20567-1:2006 (E) standard:
- - we use some white cardboard instead of the recommended white paper
- - we use some PVC Foil (~150 µm) instead of the recommended PE foil (150 - 200 µm)
But, however, as you know we are since a lot of years the manufacturer of this kind of testing machine and the current specification of the Calibration Sandwich is a result of our long lasting experience in this field.
For capture and analysis at impact images in accordance to VDA we recommend our new analysis system GRITSCAN.
Evaluation of results by camera system vs. manual result evaluation
• Any visual or manual evaluation, y ranking or classifying of the results is suffering
of the following:
– Visual evaluation & judgment trough the users‘ eyes include the “human error“– Individual impression by the user is time-limited in his mind & remembrance.– No digital documentation.
• An automatic evaluation by a digital vision system can provide the following advantages:
– Exclusion of the “human error“.– “Impression” is exchanged against measurement and the validity & access to the values is not time-limited.
– Objective, precise and repeatable results.– Digital communication
• EN ISO 21227-2 is making a good approach to describe a standard vision system to achieve reliable results.
• Design parameters of EN ISO 21227-2 as the following:
– Pixel resolution: min 6 pixel / mm
– Illumination: Diffuse bright field (recommended)
– Area of Interest (AOI): 70 mm x 70 mm (recommended)
– Threshold setting: by means of reference samples according ISO 20567-1