Molift Rail System, Проектирование и установка устройства

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Requirements to materials
Requirements/conditions to be met by some know materials are stated below. If materials not
mentioned below are used, and if the materials for some reason have been weakened, these must
be evaluated specifically. At any rate the conditions for the strength of the securing device are
stated in Table 1 and Table 2 on page 15.
Concrete structures
The quality of the concrete to which attachment brackets are to be fitted, is a crucial factor in the
ability of the concrete to withstand the loads applied by the brackets. Molift specifies concrete in
accordance with the standard NS-EN 206-1 and underlying standards. Concrete must be minimum
of the following quality if the SWL and minimal fitting times for MRS systems are to be achieved:
• Wall : B20 (C20) or better - thickness minimum 150 mm
• Ceiling : B30 (C25) or better - the ceiling must be dimensioned to bear own the
loads applied by the ceiling hoist system.
It is possible to install the system in concrete of a lower quality; then installation of reinforcement
of the concrete to meet the system requirements of MRS should be expected. Molift Group AS is
not responsible for installation or evaluation of necessary reinforcement.
If in doubt about the concrete quality, Molift Group AS recommends that tensile stress tests be
made with the securing devices used and also test loads within the minimum specifications for
vertical loads according to the valid standard (see Table 1 on page 15).
Wood structures
Wood structures are essentially wooden beams. It is important that the beams be dimensioned
to carry the load of the ceiling hoist system (see Table 1 and Table 2) and that the rail system be
placed in a position as advantageous as possible in relation to the frequency of beams. If a ceiling
hoist system is to be mounted in an existing building, it can be vital for effective installation that
there is free access to beams and loft.
In most cases it is necessary to reinforce the ceiling structure to be able to use MRS telescope se-
curing devices. The type of reinforcement depends on how far apart the beams are situated. An
open beam layer will require reinforcement between the beams. In other cases it may require
quite some work to make the required reinforcement. Molift Group AS is not responsible for instal-
lation or evaluation of the necessary reinforcement.
Leca, Brick, Siporex, Light Bricks and Light Blocks
All of these materials are more or less porous. MRS fasteners require ceiling materials to have a
compressive strength of minimum 25 N/mm2 and wall materials to have a compressive strength
of minimum 3 N/mm2. 2-component chemical anchors with or without composite sleeves are pri-
marily used in these types of materials. Both result in longer fitting times than identical fitting in
concrete.
Molift requires the producers of the elements in which MRS is planned to be installed, to issue a
statement of whether the fitting of a ceiling hoist to the elements at a construction site is recom-
mended.
Page 16 of 106 Chapter 2 – Specification of ceiling hoist system Rev E 10/2011
How to plan and mount a rail system?