TR34 2013 4th Edition (Table 3.2) Defined Movement Floor Classifications

In defined movement (DM) areas, Material Handling Equipment (MHE) travel along fixed paths. 

Defined movement areas are usually associated with high-level storage racking with very narrow aisles (VNA) in warehouses.

This section of TR34 2013 4th Edition (Table 3.2) provides guidance on controlling surface regularity in defined movement areas which takes into consideration the relationship between the front axle and read axle of the Material Handling Equipment (MHE).

Features Measured

Property dZ – Transverse permissible elevational difference in mm between the centres of the front load wheels of the MHE.

Property d2Z – Transverse permissible change in elevational difference (Rate of Change) for each 300mm of forward travel of the MHE.

Property dX – Longitudinal permissible elevational difference in mm between the front and rear axle of the MHE.

Property d2X – Longitudinal permissible change in elevational difference (Rate of Change) for each 300mm of forward travel of the MHE.

All above Properties are measured using DABROS Digital Floor Profiler, which can produce produces continuous or semi-continuous readings every 50mm with accuracy of 0.1mm. The interval between the readings can easily be adjusted to client’s requirements (for example, we can take readings every 10mm – 1000mm), however measurements taken every 50mm are sufficient enough to provide true profile of the path of the MHE.

 

Permissible limits on Properties dZ, d2Z, dX, d2X are shown in table below;

Table 3.2: Permissible limits on Properties dZ, d2Z, dX and d2X in defined movement areas.

Floor classification

MHE lift height

ZSLOPE

Property dZ

(mm)

Property d2Z

(mm)

Property dX

(mm)

Property d2X

(mm)

mm per 1m

ZSLOPE x Z

dZ x 0.75

Fixed Values

Fixed Values

DM 1

Over 13m

1.3

1.3 x Z

1.0 x Z

2.9

1.5

DM 2

8m – 13m

2.0

2.0 x Z

1.5 x Z

4.4

2.0

DM 3

Up to 8m

2.5

2.5 x Z

1.9 x Z

5.5

2.5

Z – (Transverse) distance in “m” between the centres of the front load wheels of the MHE.
X – (Longitudinal) distance in “m” between the front load wheels and the rear axle of the MHE. TR34 2013 sets it up as a fixed value of 2.0m (2000mm).

Limits Explained

Each of the properties (Property dZ, Property d2Z, Property dX and Property d2X) have 100% limit.

In order for the floor to comply with any required classification following criteria have to be met:

 

1. None of all the measurements for Property dZ, Property d2Z, Property dX and Property d2X in each individual aisle surveyed exceeds the 100% limit of the required classification;
Example:
Classification required = DM 2 with Transverse = 1300mm and Longitudinal =2000mm (fixed)
a)   100% of all Property dZ measurements recorded must have values of max. 2.6mm (2.0 x 1.3) or less in order to comply with that classification.
b)   100% of all Property d2Z measurements recorded must have values of max. 1.95mm (1.5 x 1.3) or less in order to comply with that classification.
c)   100% of all Property dX measurements recorded must have values of max. 4.4mm or less in order to comply with that classification.
d)   100% of all Property d2X measurements recorded must have values of max. 2.0mm or less in order to comply with that classification.

Static Lean

Below is an example of how truck lean increases with lifting height.

This is based on the truck with rigid mast, however due to the engineering tolerances in the mast and the dynamic forces when the VNA truck is in motion, values in the table could increase by up to 3 times.