RCF nx series, Руководство пользователя

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NX L23-A SUSPENDED
GENERAL RIGGING WARNINGS AND SAFETY PRECAUTIONS
- Suspending loads should be done with extreme caution.
- When deploying a system always wear protective helmets and footwear.
- Never allow people to pass under the system during the installation process.
- Never leave the system unattended during the installation process.
- Never install the system over areas of public access.
- Never attach other loads to the array system.
- Never climb the system during or after the installation.
- Never expose the system to extra loads created from the wind or snow.
WARNING: The system must be rigged in accordance with the laws and regulations of the Country where the system is
used. It is responsibility of the owner or rigger to make sure that the system is properly rigged in accordance with Country
and local laws and regulations.
WARNING: Always check that all the parts of the rigging system that are not provided from RCF are:
- appropriate for the application;
- approved, certified and marked;
- properly rated;
- in perfect condition.
WARNING: Each cabinet support the full load of the part of the system below. It is very important that each single cabinet
of the system is properly checked.
“RCF SHAPE DESIGNER” SOFTWARE AND SAFETY FACTOR
The suspension system is designed to have a proper Safety Factors (configuration dependent). Using the “RCF Shape Designer” software
it is very easy to understand safety factors and limits for each specific configuration. To better comprehend in which safety range the mechanics
are working a simple introduction is needed: NXL23-A mechanics are built with certified
UNI EN 10025-95 S 235 JR Steel. RCF prediction
software calculates forces on every single stressed part of the assembly and shows the minimum safety factor for every link.
S 235 JR is a structural steel and has a stress-strain (or equivalent Force-Deformation) curve like the following:
The curve is characterized by two critical points: the Break Point and the Yield Point . The
tensile ultimate stress is simply the maximum stress attained. Ultimate tensile stress is
commonly used as a criterion of the strength of the material for structural design, but it should
be recognized that other strength properties may often be more important. One of these is
for sure the Yield Strength. Stress-strain diagram of S 235 JR exhibit a sharp break at a stress
below the ultimate strength. At this critical stress, the material elongates considerably with
no apparent change in stress. The stress at which this occurs is referred to as the yield point.
Permanent deformation may be detrimental, and the industry adopted 0.2% plastic strain as
an arbitrary limit that is considered acceptable by all regulatory agencies. For tension and
compression, the corresponding stress at this offset strain is defined as the yield.
Ultimate
Strength
N/mm
2
Yield
Strength
SF = 4
Working
Conditions
%