Basic
Rigging Concepts
Working
within the oil and gas exploration and producing industries requires a commitment
to safe work practices due to the volatile forces that employees face on a daily
basis; high pressures, extreme temperatures, the fury of the oceans, and complex
equipment on the cutting edge of technology! The complexity of the varied multitude
of procedures undertaken by these dedicated men and women, often working in
harsh and remote environments, leaves little margin for error.
The nature of the energy
industry requires moving equipment, tools, supplies, and even personnel to and
from isolated locations. Usually there are no roads leading to a loading dock
where you work.
A great deal of this responsibility
lies with the crane operator and the assisting riggers. It is their job to safely
and efficiently utilize the lifting machinery and rigging gear available to
them in order to support all ongoing operations. Cranes, rigging, and the personnel
who harness and control their power are some of the most essential players on
the energy exploration and production team. 14 min.
| Questions
to Insure Safe Rigging Operations |
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Who
are the competent persons responsible for rigging the load and establishing
lines of communication?
* Are the rigging gear and crane components in acceptable condition, suitable
for lifting and properly identified?
* Are the working load limits adequate, taking into account the following
conditions: |
weight of
the load?
sling angle?
capacity of the gear?
need for padding slings against sharp corners?
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Will the load be under control? |
Is the hitch
appropriate?
Is the load rigged to the center of gravity?
Is a tag line available?
Is there any possibility of fouling or snag- ging of the load
on nearby obstructions?
Will the suspended load be clear of all personnel?
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* Do any
unusual side loading or environmen- tal conditions such as excessive wind,
waves or temperature exist?
* And are there special requirements imposed by the customer or local regulations?
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| Before
Starting A Lift |
| Before starting a lift
the following conditions must be verified so that the load is free to be
lifted from the deck or ground. |
- If a slack rope
condition exists, check that the wire rope is properly seated on the
drum and in the sheaves. No fewer than 5 full wraps of rope should remain
on the drum in any operating condition.
- Position the hook
directly over the load in such a manner as to minimize swinging upon
lifting. No external forces should be applied to loads which will create
side loading of the boom. Cranes are not to be used for dragging loads!
- Care should be
taken when swinging the crane in order to minimize the pendulum action
of the hook and suspended load.
- Select appropriate
slings and hardware checking their rated capacity and making sure they
are sufficient for the weight of the load to be lifted.
- The hoist rope
is never to be wrapped around the load. The load must always be attached
to the hook by means of slings or other suitable devices.
- Be sure to untangle
any multiple part lines that would not separate upon application of
the load.
- Attach a tag line
to control the swing of the load.
- Make certain that
the load is secured and properly balanced in the sling or lifting device
before it is lifted. If the load shifts, set it back down and adjust
the rigging.
- Always check that
the lift and swing paths are clear of obstructions and personnel. The
Operator should avoid moving loads over personnel.
- The operator will
not hoist, lower or swing while any personnel are on the load or hook.
A certified Personnel Basket or carrier is required for transporting
personnel.
- The hook latch
must be closed to secure loose slings. All hooks used for support of
personnel must be of the type that can be closed and locked including
a safety latch with a redundant locking method.
- When making personnel
lifts, the load must be under control in both the up and down directions.
No Free Fall. All personnel to be lifted will use approved personal
flotation devices and should stand on the outer rim facing inward.
- Loads which are
suspended by use of slings or hoists should be blocked or cribbed before
personnel are permitted to work beneath or between them.
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| Hand
Signals |
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When signals are required
to control operations, a designated signal person will be assigned to
work with the crane operator. Reliable radio communication protocols and
the use of standard hand signals are encouraged.
Shown here is a hand
signal chart published within the API offshore standard RP2D. These standardized
signals are recommended for all crane operations regardless of location.
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