VDMA Standard

Verband Deutscher Maschinen- und Anlagenbau e.V. (Association of German Machine and Plant Construction) is a German engineering association which publishes industry standards.

The VDMA guideline standards are used to describe the floor levelness and flatness in a defined movement VNA.

Although Face can check compliance with the VDMA guidelines, we do not currently endorse the recommendations as they have yet to be validated and peer reviewed.

The Specification

The VDMA Guidelines have three properties of surface regularity:

Table A.1 Limiting values of ZSLOPE

Top beam level (m)	ZSLOPE (mm/m)	dz = Z x Zslope
15	1,0	Z x 1,0 mm/m
10	1,5	Z x 1,5 mm/m
up to 6	2,0	Z x 2,0 mm/m

Table A.2 Limiting values along the tracks

Distance between measurement l	Gap under straight line t
1m	2mm
2m	3mm
3m	4mm
4m	5mm

Table A.3 Limiting values of Fx or Fx, avg

Top beam level (m)	Fx or Fx,avg
The values of FX or FX avg Waviness Numbers for all wheel tracks and all 2m sections shall exceed the values given below
15	525
10	400
up to 6	300

1.Transverse

The elevational difference in mm between the centres of the front load wheels of the forklift truck.

2. Longitudinal – In accordance with DIN 15185

The longitudinal property of DIN 15185 is derived from the DIN 18202 specification being based around a straight edge of variable lengths.

3. Longitudinal micro small wavelength – ‘Fx’ number.

The VDMA Guidelines have a surface regularity property that controls a micro short wavelength of the floor profile. This property controls the rate in change of slope over two elevation readings 50mm apart to fractions of a millimetre.

The device or ‘Fx’ meter incorporates 9 wheels on three axles and each wheel being 40mm diameter. The wheels are made of steel and the edge is tapered to a width of 0.5mm.

Face Digital ‘Fx’ meter

Photo 1: Face Digital ‘Fx’ meter – 40mm diameter wheels tapered to 0.5mm wide at rim.

Rate of change readings are taken every 50mm of travel down the wheel tracks and an ‘FX’ number is calculated from 38 such readings (total distance travelled being 2 metres). Every 2 metres travelled, an ‘Fx’ number is calculated for each wheel track. The higher the ‘Fx’ number the smoother the floor surface.

Test Instruments:

It is recommended that a continuous method of measurement should be adopted in all cases of defined traffic movement.

For continuous measurement, the Face DIN Profileograph is used. The DIN Profileograph is a self propelled wheeled instrument which travels along the centreline of the VNA aisle taking continuous measurements both transversely and longitudinally as it does so. The DIN Profileograph is
adjustable so that the skates run in the wheel tracks of the front load wheels of the MHE.

These readings are generated by the three sensors, which are set up to measure the longitudinal and transverse properties of the specification. These readings are collected on a data logger and are subsequently downloaded to a PC where our software generates the graphic traces and compliance results.

For the Longitudinal micro small wavelength measurement or ‘Fx’ number the Profileograph is fitted with the ‘Fx’ meter.