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NOTICE: This guide contains important information about the use and
characteristics of the Vulcan Pile Hammers. Because misuse of this
machinery may result in injuries to personnel and the loss of property,
this guide should be carefully reviewed by all maintenance, operating and
support personnel.
INTRODUCTION
Today's Vulcan Pile Hammer is the product of over one hundred years of
engineering and manufacturing experience. Every component of the machine
has been designed for maximum reliability and is fabricated from the most
suitable materials available. Although we feel this machine has earned a
reputation within the construction industry for both reliability and
safety, we also feel that it is our duty to convey to you potential
hazards associated with its use.
This User's Guide presents a discussion of each of the general types of
hazards which must be considered for the successful use of the Vulcan Pile
Hammer. Although considerable effort has been made to identify situations
which may involve risk to personnel or property and to suggest how these
risks may be avoided, nothing will substitute for good maintenance and
well trained operators.
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I. OPERATING TECHNIQUES
The pile hammer should be used only by well trained and experienced
personnel. Before using the hammer all instruction and safety manuals
should be thoroughly reviewed by all operating and maintenance personnel.
These references are an invaluable source of information and should be
retained by the owner for future study and to train new employees. Copies
of these manuals should be kept with the hammer at the construction site
for ready access. Additional copies are available from Vulcan.
Safe use of the pile hammer, as with any machine, is dependent upon the
skill, knowledge and concern of those who maintain and use it. Because of
the wide variety of environments and applications in which this machine
may be used, a comprehensive description of detailed rigging and operating
techniques within this booklet is not possible. (Specific requirements
should be addressed to Vulcan's engineering department.)
For reasons mentioned elsewhere, no one should be any closer to the
hammer during driving than is absolutely essential. All workmen should
wear safety clothing including hard hats, safety shoes, safety glasses and
hearing protection.
Before, and periodically during usage, a complete inspection should be
performed on the hammer and all associated equipment to insure operational
integrity. The associated equipment includes items such as the compressor
and/or boiler, hoses and hose couplings, leaders, support and lifting
equipment and all rigging, etc. On the hammer, particular attention should
be given to sheaves, pins, retaining bolts, hose couplings, the valve
mechanism, all keys, ram point, pile cap, and the lifting points.
Supervisors should be certain that all inspection and maintenance is
properly done.
During the driving operation and whenever the hammer is moved, constant
supervision and inspection should be provided. If abnormalities are
observed, driving should be stopped immediately. One example would be that
of the loss of one or more ram keys. If both keys are missing, then the
ram would obviously no longer be connected to the piston. Without the ram
to slow the acceleration of the piston on the up stroke, the piston may
impact into the cylinder head with catastrophic effects. Another dangerous
situation would be to continue hammer operation without a piling seated in
the pile cap. In this event, the entire force of the falling ram could be
absorbed by the hammer's columns, base and pile cap. Few such strokes
could be sustained without severe damage to the hammer. Obviously, such
destruction would be hazardous to anyone in the vicinity. Also, the
cylinder head lifting points (sheave, axle, pins, keys and nuts) should be
continuously checked for worn, loose or missing parts. Damaged or missing
components oif this assembly could cause hammer to disconnect from rigging
and fall.
The effects of unregulated steam or air pressure may also create a
risk. As noted elsewhere, failure of any of the hose couplings, while
under pressure, could be very dangerous. In addition, operation at
pressures either higher or lower than specified design should be avoided
since structural damage to the hammer or inefficient operation may result.
Obviously, all air or steam supply hoses must be properly sized to avoid
undue flow restrictions.
Damage to the pile, pile cap, ram point and piston can occur if the
alignment of the hammer and the pile is not correct. That is, the central
axis of the hammer should be in alignment with the central axis of the
pile and the pile end should be square and uniform. If the error in
alignment is great, the hammer will receive an unbalanced structural
loading which could result in either a fatigue failure in the hammer or a
significant shortening of its useful life. Obviously, this type of
condition could be both expensive and dangerous, but can be avoided with
reasonable care.
A common pile driving criterion is to drive until a certain number of
blows per foot of pile insertion is achieved. This measure is based on the
amount of energy delivered with each stroke of the ram. In a single acting
hammer, the energy is dependent upon the falling weight and stroke length.
Since falling weight is constant, only changes in stroke length can affect
the energy delivered. Therefore, if a variable stroke hammer is used, it
should be noted that the blow count taken is compared to the proper stroke
energy, i.e., the blow count criterion will vary with the stroke length
used. The supervisor should correlate the blow count criterion and the
stroke length. Otherwise, pile damage, added expense, or inadequate pile
installation could result. It should also be noted that significant
deviations in pressure delivered to the hammer from the recommended
pressure may affect the actual operating stroke length and thus influence
the energy in each blow of the hammer.
Since the pile hammer is such an extremely powerful machine, it is
conceivable that even with normal operation, surroundings at the driving
site could be damaged. Operators should take every precaution to see that
exhaust from the hammer and vibration of the earth are not a threat to the
area surrounding the driving site. Failure to do so could be unsafe and
possibly lead to expensive property damage.
As an additional precautionary measure, a pre-pile driving survey could
be made.
Given the respect it deserves, the pile hammer should provide years of
safe service. However, the ultimate safety and reliability of the hammer
rest in the hands of the user.
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II. FALLING OBJECTS AND PROJECTILES
The pile hammer is a relatively large and heavy machine which is
normally used in a suspended position. Consequently, gravity can propel
the hammer or any of its parts downward with great force. Therefore, every
effort should be made to see that neither the machine or any of the
hammer's component parts are permitted to fall.
Supporting and lifting tackle should be of sufficient capacity to
safely lift the weight of the hammer and to withstand the vibration of its
operation. (See gross weight label on machine.) Likewise, all rigging
should be heavy enough to handle the load safely and the entire system
should be thoroughly inspected to insure its integrity before it is used.
Refer to relevant standards-A.N.S.I. B-305; O.S.H.A. 1926.550 and 251;
P.S.C.A.#1.
Since the hammer may be suspended well above the work level, all
personnel should remain clear of the area. Barricades could be set up
around the area for additional safety. Even an object such as a stone,
bolt, or scrap may adhere to the hammer when laid down and if dropped from
the hammer's suspended height could cause harm. In addition to remaining
clear of the area, steps should be taken to prevent any parts from
dropping into the system. Such things as bolts, nuts, keys, fasteners,
wedges and couplings should be tightened and checked before each use and
after each drive during use. Good maintenance cannot be overemphasized in
promoting the safe and efficient use of the hammer.
In addition to free falling objects, it is possible that projectiles
can be thrown out during operation. Any foreign material in the lubricant,
supply hose or cylinder may be ejected through the exhaust at high
velocity. Personnel should therefore remain clear of the exhaust to avoid
this risk as well as to avoid being burned by the exhaust steam or air.
If the air or steam lines are either not properly secured by chain or
heavy rope, or if they fail in use they can become extremely dangerous. To
reduce the risk of this occurring, all couplings should be checked before
use and all hoses must be secured to the hammer just below the couplings.
Refer to O.S.H.A. Standards 1926.603 (a) (9) (10). This will prevent the
hose from whipping wildly over a great distance if the coupling should
fail.
The ram point and the pile cap take a lot of punishment during driving.
With use, fragments of metal may be broken or spalled off and ejected with
the speed of a bullet. The risk can be reduced by repairing or replacing
worn ram parts and pile caps, assuring that the pile is squarely cut,
seating the pile in the cap properly while driving, assuring that the
hammer is driving squarely, and using the appropriate pile cap. After each
drive, a visual inspection of the ram point and cap should be made,
staying well clear of the hammer when in use.
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III. PRESSURE AND WEAR FAILURES
Although unlikely to occur under normal operating conditions, hose
failure can cause substantial injuries to personnel and property since the
steam or air pressure used is typically over 100 PSI. This line pressure,
when distributed over a few square inches of area, generates a tremendous
force which will cause an unsecured broken hose to whip in a violent
unpredictable way. Since such a condition could produce a substantial
injury, precautions must be taken to see that this does not occur.
The air/steam supply hose should be secured to the hammer by heavy
chain or rope of adequate strength (refer to O.S.H.A. Standards 1926.251),
attached to the anchor point on the hammer with a shackle. Inspection of
this connection should be made at the beginning of each shift and after
the driving of each pile.
Another critical point of the hammer is its valve mechanism and as
such, requires regular inspection and maintenance. With normal
functioning, air or steam is admitted to the cylinder and released in
alternating cycles. After release, the ram falls and impacts with the pile
cap. If steam or air is not permitted to enter the cylinder freely or if
it is not relieved, there is a possibility that a major structural problem
could occur.
The valve mechanism could be jammed by foreign material or it could be
broken through misuse or improper handling. However, regular inspection,
cleaning and lubrication will reduce the likelihood of trouble.
Nevertheless, special attention should be given to the slide bar and
wedges, the valve, and the actuating levers at each opportunity. At all
times, personnel should stay clear of the hammer until the ram is resting
on the base.
Complete inspection and maintenance should be performed at the
beginning of each shift and/or after the hammer has been inoperative for
over an hour. Cylinder head nuts, the head itself, the cylinder and
columns should be given attention. All keys wear and loosen with use and
should therefore be checked and secured after each drive. Since they are
heavy, a key could be dangerous if it should be dislodged and fall from
the hammer. In addition, if both ram keys should be lost during use, the
ram would not be secured to the piston and without the inertia and weight
of the ram to retain it, the piston could be driven through the cylinder
head. Therefore, key condition is obviously very important for safe
operation and should be carefully maintained.
Because of wear that occurs during prolonged use, the ram point and
pile cap may fragment from metal fatigue. This fragmentation will be
accelerated by improper use, such as by misalignment of the hammer axis
with the pile and by using a pile cap of inappropriate size. The fragments
may be violently ejected during driving and could be a threat to personnel
safety. Therefore, both the ram point and pile cap should be checked after
each drive and if excessive spalling or cracking is found, should be
repaired or replaced. It is essential that the axis of the hammer be
closely aligned with the axis of the pile and that the pile cap should be
matched to the size of the pile being used. All personnel should remain
well clear of the hammer during use, reducing the risk of being struck if
fragmentation should occur.
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IV. EXPOSED MECHANICAL HAZARDS
Probably the most obvious danger in working around the pile hammer is
that of its exposed mechanical parts. Crushing, pinching or shearing can
occur if workmen contact moving or movable parts of the hammer. Even the
small parts of the hammer are heavy and can cause serious injury if they
shift position. Workmen should remain well clear of the exhaust, valve
mechanism and slide bar, columns, supporting rig, the ram, pile cap, and
the ram point during the operation of the hammer. These areas should be
avoided at all times. Failure to do so may result in serious injury or
death. If it becomes necessary to work on the hammer, it should be cooled
after use, the ram should be blocked, residual air or steam in the
cylinder and steam or air lines should be relieved, after having been shut
off. Steam or air pressure lines should be disconnected and the hammer
should be in a secured position.
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V. HIGH TEMPERATURE HAZARDS
Although the pile hammer is constructed of non-flammable materials, the
high temperature generated during use can pose a threat to the user if
caution is not used. The types of hazards that may be produced are, first,
the combustion of materials associated with the use of the hammer and,
second, burns from contacting the heated parts of the machine. During use,
the hammer will get hot as a result of the tremendous energy that is
expended with the expansion of steam or air in the cylinder and with each
blow of the ram. Although it is unlikely, it is possible that the heat
will be sufficient to ignite some lubricants that may be used on or around
the hammer. Information regarding the combustibility of the lubricants can
be found either on the container or can be obtained from the manufacturer.
Keeping the machine reasonably clean and avoiding the build-up of dirt
that could absorb oil and grease will reduce the risk of fire.
Cushion material, having been subjected to impact of the ram does
experience very high temperatures. There is little chance of most
materials actually flaming during use if they are the ones recommended by
Vulcan and used in the recommended manner. However, when the material is
removed and has access to open air, some materials may burn or come in
contact with another material that will burn. Therefore, used cushion
material should be stored or disposed of in a place and in such a way that
it will not create a risk as a source or transmitter of fire.
During use, for reasons previously mentioned, the hammer can become hot
and this heat can be retained for a long while after use. Consequently,
during or just after the use of equipment, workmen should exercise caution
when in the vicinity of the hammer to avoid being burned by contact with
hot metal parts.
When steam is being used, special caution should be used. High pressure
steam is extremely dangerous if not treated with respect. Also, condensed
steam may drip off the hoses or the hammer and could cause serious burns.
Since there is some chance of fire, an approved type fire extinguisher
should be kept on hand at all times and a burn treatment kit should be
kept with first aid materials. Being alert and aware of the hazards is a
good defense against them.
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VI. AIR CONTAMINATION
When working in the vicinity of an operating pile hammer, some
consideration should be given to the possibility of air contamination.
Almost without exception, the exhaust of a hammer will contain
contaminants. The most common of these are traces of lubricant emitted in
the form of oil droplets or vapor. Two hazards are associated with this
emission. First, the contaminant may be harmful to the respiratory system
and second, it may cause damage to material that it contacts if the
contamination is very great. Consequently, one should not get into the
exhaust stream, and steps should be taken to avoid letting the exhaust
spray get onto surrounding buildings, vehicles, etc.
Since the exhaust is merely the release of air or steam that is used to
drive the hammer, any contaminants associated with the generating of
compressed air or steam and transporting it to the hammer may be present
in the exhaust. This system should be checked,maintained,and cleaned to
prevent such contamination. The system includes the air compressor or
steam boiler and the hoses running to the hammer.
Possibly the least likely source of air contamination is the cushion
material that is used beneath the ram point. Because of the tremendous
energy that must be transmitted by this material, it tends to fragment,
decompose and sometimes burn. For most materials, this should not be a
significant problem, but there are exceptions. One material that is
commonly used by cushion manufacturers contains asbestos. When the
material decomposes in use, the asbestos fibers are free to become
airborne. If the asbestos fibers are inhaled, permanent lung damage known
as asbestosis may occur. The material should be inspected and if there is
any suspicion that the asbestos or the fibers are becoming airborne, an
approved filter mask should be worn by all workmen in proximity of the
material. WARNING: Use in "confined spaces" may be hazardous to
health. Refer to O.S.H.A. Standards 1910.1000, Air Contaminants, and
1910.134, Respiratory Protection.
For each cushion material, lubricant, or other fluid used, the health
hazards should be identified by the user and appropriate precautions
should be taken. If the hazards are not readily identifiable, the user
should consult with the manufacturer of the material or with a certified
Industrial Hygienist.
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VII. HEARING DAMAGE
There are two primary types of noise which are produced by any pile
hammer. The first is impact noise produced by the ram striking the pile.
The second type of noise is produced by the operating steam or air as it
is exhausted from the cylinder. In both cases, depending upon hammer size,
it is possible to produce noise levels which are potentially damaging to
the auditory mechanism in the ear.
At present, there are not too many practical ways to reduce these noise
levels. In the case of impact noise, cushion material can be used to
reduce the noise levels as well as modify the impulse duration as required
by soil type and piling composition. The exhaust noise can also be reduced
through the use of an exhaust muffler. However, if it is impractical to muffle the
exhaust, there are other alternatives which will provide
construction personnel with adequate hearing protection. Because sound
intensity decreases rapidly as the distance from the hammer increases,
simply keep all personnel as far from the hammer as is practical.
Obviously, there are many other safety reasons why no one should be near
the hammer when it is in use. However, if personnel cannot be stationed
far enough from the hammer to adequately reduce the noise, earmuffs or
earplugs should be used. If there is concern about the noise level at any
job site, it is advisable to use a sound level meter to establish what
abatement procedure is needed. It is obvious that the user must give more
attention to the noise problem as ever more stringent environmental safety
restrictions are imposed by government authorities. Refer to O.S.H.A.
Standards 1910.95 and 1926.52, Occupational Noise.
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VIII. SHIPPING PRECAUTIONS
The foremost source of difficulty in shipping or moving the pile hammer
is its size and weight. Whether the hammer is laid on a platform, vehicle,
or a vessel, it should be determined that its support is adequate and that
the hammer is well secured. Likewise, the hammer should be lifted only by
equipment of sufficient capacity and all rigging should be thoroughly
inspected beforehand. Before lifting, check gross weight label, located on
machine. If any tilting, vibration or accelerative loading is
anticipated, such as on a vessel or vehicle, the hammer should be secured
in position. This can be more easily done with the aid of a shipping skid
which can be supplied by Vulcan. Of course, it is essential that the
ropes, chains or fasteners used for securing the hammer be sized
adequately to withstand the load. If the hammer will be subjected to any
tilting, vibration or accelerative loading, it is necessary to block the
ram in order to prevent the ram from sliding and impacting without a
piling to absorb the shock. A sliding ram can transmit a large impulse or
shock to the securing devices that hold the hammer in place which may
cause the hammer to break free and thus pose a threat to the safety of the
crew, transporting vehicle or vessel. At all times, when not in use,
secure the ram at the lower extremity of its travel and shim or brace it
in place with wood or steel blocks and wedges. If a Vulcan designed
shipping skid is used, it will provide proper support areas and a secure
relationship between ram, base and piston.
Another consideration is that the carrier, whether vessel or vehicle,
must be of sufficient capacity to handle the load and that the carrier
should observe the operating limitations of the vessel or vehicle with
that load (more than one flatbed trailer has been collapsed from improper
loading of a hammer). Always refer to the gross weight label on the
machine before attempting to move, load or transport.
If it is expected that the shipment will take an extended period of
time, the same precautions should be taken as for storage.
These include inspection, lubrication, rust proofing and sheltering of
the hammer. After shipment and before being placed in operation, a
thorough inspection should again be performed to assure that no shipping
damage was done and that the hammer is in operable condition. This will
preclude the possibility of placing a damaged or defective hammer into use
and thereby creating a hazardous situation.
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IX. STORAGE PRECAUTIONS
If the pile hammer is to be stored or out of service for an extended
period of time, certain precautions should be taken to prevent damage to
the hammer and risk to personnel.
A storage or resting place should be selected which will adequately
support the weight of the hammer. The site should be level, firm, and a
protected area. Keep the hammer off the ground. This can be done by using
the original shipping skid or resting the hammer on two 8" x 8"
wood beams. In addition, because of the hammer's great weight it should be
secured to preclude damage from unexpected movement. The ram should be
properly blocked in the down position. This is accomplished by using a
4" x 4" timber wedged between the cylinder and the ram and
securing the timber to a column with banding iron. The 4" x 4"'s
should be used on diagonally opposite columns.
After its use, a thorough inspection should be performed. If any
defects are found, they can be repaired during the storage period,thus
preventing malfunction, danger or on the job downtime.
Before storage, a complete lubrication and rust proofing should be done
in order to protect the hammer from the elements and subsfequent
corrosion. For further protection, a cover of canvas or plastic can be
used to provide shelter, and thus reduce the effects of exposure to the
environment.
When the storage period has ended and it is time to put the machine
back into service, another thorough inspection, cleaning and lubrication
will assure that the hammer is ready for service.
By taking these few precautions, the life of the hammer can be
extended, its efficiency can be maintained, and its safety greatly
enhanced. Detailed instructions on preparation for storage including
inspection procedures and lubrication requirements are given in the Field
Service Manual, supplied with each hammer by Vulcan.
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X. MAINTENANCE AND REPAIRS
Repairs by anyone other than Vulcan Foundation Equipment
Inc. or its authorized
representatives or use of replacements parts other than Vulcan Foundation Equipment
Inc. parts will void all warranties covering the hammer.
By closely following the Owner's Field Service Manual and the User's
Guide, many years of reliable operation will be possible. However, the
manufacturer will not be responsible for improper maintenances or use not
in accord with recommendations given here or in the Vulcan Field Service
Manual.
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