How Vulcan Extractors Work

Vulcan was generally not hesitant to include information on the cycle workings of its air/steam hammers, but for some reason never included similar information on its extractors.  Above is a diagram from 1940 which shows how this is done.

Basically we start with the view on the left.  Air or steam is admitted through inlet I and is passed through chamber C to the area below the piston.  The ram rises, since the large area at the ram bottom is pressurized.  During the ram rise/upstroke the middle piston rings close off chamber C (right view) and port P and the ram rises by the expansion of the air or steam below the ram.  The ram hits the anvil at the top of the stroke, which through the side bars jerks up whatever is attached to the extractor at the bottom.  Towards the top of the stroke the air or steam under the piston is exhausted through E, the ram comes to the bottom of the stroke, and the cycle begins again.

The drawing above shows a coil spring at the bottom of the stroke to soften the impact of the ram to the bottom of the extractor.  Later Vulcan extractors used a rubber spring and conversion from one to another is shown here.

The extractor’s cycle anticipated the Single-Compound hammer by its expansive use of air.  Specifications on Vulcan extractors can be found here.

Onshore Hammer Clearance Dimensions

Above is a clearance chart from 1979 of Vulcan’s onshore air/steam hammers.  The clearance chart is helpful in that it can show whether your Vulcan hammer can fit into a given set of leaders.

One thing to keep in mind is that, if your leaders have a low distance from the front to the back rail, small clearance may not be your only problem.  The distance from the front to the back rails on U-type leaders is a major part of their strength; the larger that distance, the higher the section modulus of the leaders for given front and back rail configuration.

Slide Bar Gripper

Main drawing for U.S. Patent 3,455,208, showing the basic layout for the original slide bar gripper.  Note that the hammer itself was held together with cylinder and base keys, something that was soon to disappear from Vulcan offshore hammers.

Once Vulcan got past designs such as this, the slide bar (the cam which turned the valve during operation) was retained in a ram using a key driven though the base of the slide bar.  The slide bar interfaced with the ram using a spherical block to allow rotation of the bar, necessary to compensate for alignment changes.  This worked until the advent of nylon slide bars, which became de rigeur for offshore hammer during the 1960’s and onshore a little while later.  These were more prone to split with driving the key.

The problem was solved by moving the key under the slide bar and using a gripper to hold the slide bar to the key interface.  It was invented by Campbell V. Adams, Vulcan’s long time chief engineer, and he was granted a patent on it in 1967 (it was Adams’ last patent for Vulcan.)

The gripper concept went through several variations; the last one was the design shown at the top.  This one was used in the 3100, 5100 and 5150 hammers.

An early layout of the slide bar gripper.


Vulcan Hammers: Specifications and Information

One thing Vulcan representatives got ask frequently for was a “spec sheet” for a particular hammer.  This is an online answer to that question.  Our pages include specifications, general arrangements of the hammers, photos and usually some history behind the hammer model.  We trust that this will be helpful to you in servicing your existing Vulcan hammer.  Remember you can contact us here if you have any questions.

Single-Acting Hammers (Onshore and Offshore)

Differential-Acting Hammers (Onshore and Offshore)

Raymond Hammers

  • 65C

    A explanation of differential hammer operation, from the Raymond Superintendent’s Handbook.
  • 80C

Vulcan 5150: Specifications and Information

Progressing from the 5100, the six (6) 5150’s produced were made in 1978-9 and delivered to four customers: McDermott, Brown & Root, Raymond and Santa Fe.  Their main purpose was to drive piles for the “mudslide” platforms at the mouth of the Mississippi River, which were suffering failures due to scour loads.

Specifications for the hammer are below.

The general arrangements are below.  The hammer was produced in two (2) versions: a 120″ jaw version for 96″ diameter pile, and a 144″ jaw version for 120″ pile.

Like the 040 and 060 hammers, the hammers had growing pains, in part due to their sheer size and in part to some changes Vulcan made to the basic design that didn’t work out.  Vulcan stood behind its products and remedied the faults.  The hammers successfully drove many piles in the Gulf of Mexico in the years immediately after they were produced and, forty years later, are still at work in the same Gulf today.

Vulcan 5110: Specifications and Information

The 5110 was the last new model that Vulcan “produced” and was the first beneficiary of Vulcan’s acquisition of Raymond technology in the early 1990’s.  The one and only 5110 came into being by a conversion of a 560 owned by Global Movible Offshore.  This resulted in a hammer that was considerably lighter than the 5100 with slightly larger energy.  The conversion was done by changing the ram, columns and a few other small parts.

Specifications for the 5110 are below.


A general arrangement is below.


Ram point installation by cooling the point. Breakage of ram points is a major repair job in a Vulcan hammer (caused, in some cases, by use of wire rope biscuit as you see above.) Getting the “stump” of the point out was half the battle; click here for Vulcan’s recommendations. Putting one in was the other (also important for new rams and points.) For the smaller hammers, a press would do, but for hammers such as the Vulcan 5110, the best way was to shrink the point through freezing the small end (the “stump” when broken,) lifting it up and lowering it into a ram turned upside down. Although Vulcan installed points in new and used rams using this procedure, this is a very delicate procedure, failure of which could result in a cracked ram, point, or having the point hung up in the ram, which ruins both. As they say, “don’t try this at home!”

Vulcan 5100: Specifications and Information

With the success of the 560 the 5′ stroke concept was taken upward with the 5100, an extension of the 3100.  In addition to the longer stroke, it was Vulcan’s first hammers with 120″ jaws, to accommodate 96″ piling.  The first 5100 was sold to Brown & Root (Western Hemisphere Marine, to be formal about it) in 1977 and, like the 3100, was assembled in the customer’s yard, in this case at Green’s Bayou in Houston.

Specifications are here:

General arrangement is here:

The 5100 saw active service in the Gulf of Mexico and elsewhere.

The biggest problem Vulcan had with the 5100 was its sheer size.  The territory into which Vulcan was venturing was stretching its own capabilities along with those of the U.S. foundry industry.  Nevertheless, once these problems were resolved, the 5100 did well in service.

Vulcan 560 Hammer: Specifications and Information

The Vulcan 560 hammer became the “#1 of Vulcan offshore hammers,” and the most popular of its offshore hammers from the 1970’s onward.  Yet, although today the logic of a 5′ stroke hammer (especially when compared to the diesel hammers) is obvious, at the time it took a little persuading.

Vulcan had adhered to the “heavy stroke/low striking velocity” concept since the beginning, but by the early 1970’s the “race to the top” for hammer size–driven by the larger and deeper conventional platforms–was getting ahead of the barge capabilities of Vulcan’s largest customers.  In the Gulf of Mexico that principally meant McDermott and Brown and Root, but also Santa Fe, Teledyne Movible Offshore and (a little later) Raymond.  Basically when facing the need for a 300,000 ft-lb hammer, Vulcan’s “traditional” choice would be one like a 3100, which would weigh around 200,000 lbs. (100 US tons) plus cap and leaders.  For many of the barges in the Gulf, that would necessitate the use of the main block to pick up the hammer and follow it as it drove the pile.  The main block was okay for topsides and pile lifts, but in the constantly moving situation with a hammer, it was too slow.

A lighter hammer would allow the contractor to drop to the secondary block on the crane, the traditional block to use for hammers.  This block could raise and lower the hammer faster, and give the crane operator more control over the hammer during both lift and operation.  Vulcan “bit the bullet” and proposed the 560, which lowered the ram weight (and thus the frame weight) to around 30 US tons while preserving the striking energy with the 5′ stroke.

Vulcan presented the 560 to its customers, to mixed reviews.  McDermott stuck with the 3′ stroke concept with the 3100.  Its larger bench of barges–with the crane capacity to go with it–made the 3100 a more viable option for McDermott.  But others–specifically Brown and Root–found the idea attractive, and B&R ordered the first 560 in early 1973.  It was delivered later that year (a delivery which beat McDermott’s 3100 by almost two years!) and proved successful without too many “growing pains” such as were experienced with the 040 and 060.

Specifications are shown below.

Some general arrangements–including later CAD ones from the 1990’s, showing the durability of the model–are shown below.

Some photographs of the hammer are shown here:

The 560 became the “standard” for offshore hammers, not only for Vulcan’s American customers but for its foreign ones as well, such as Micoperi, ENAP, Petrobras, Hyundai, Daelim, Jardine and of course CNOOC, the sale to which of two (2) 560’s is documented here.  It also found onshore use with such customers as Manson Construction.

The irony of Vulcan’s “gamble” with the 5′ stroke is that it turned out to be an advantage.  All other things equal (especially the cushion stiffness,) for a given energy a lighter ram with a higher impact velocity will produce an impact pulse with a higher peak force and shorter duration.  With steel piles, this is something of an advantage; their ability to withstand the higher stresses allows higher impact forces and stresses.  With concrete piles, a heavier ram and lower impact velocity is favoured, as it results in lower compressive and tensile stresses during driving.  The stage was set for more 5′ stroke hammers, and the 560 not only was the first to try the concept but was its most popular example offshore.

Vulcan 540 Hammer: Specifications and Information

With the success of the first 5′ stroke hammer, the 560, Vulcan proceeded to do the same to its successful 040/340 hammers with the 540.  The first 540 was produced and sold to Conmaco and delivered in 1974.  Specifications are below.

The hammer benefited from the many improvements in the 040 and the introduction went smoothly.  Some general arrangements (all of which are two-sheet versions, normal for Vulcan offshore hammers at the time) are below.

Vulcan 540 at the plant in Chattanooga. Standing next to it is Norris Tremmier, Vulcan’s field service representative based in Chattanooga.

Although never as popular as the 560, the hammer saw extensive service in the oilfield.

Vulcan 520, 530 and 535 Hammers: Specifications and Information

This series of hammers, an outgrowth of the 020 and 030 hammers, had a complicated history, as its development alternated between onshore and offshore configurations and applications.  Because of this they have proven versatile hammers applicable in both fields.

The first of the series was the 530, which was first developed and sold in 1978-9 to Teledyne Movible Offshore and Santa Fe Engineering.  It was an offshore hammer, with the male jaws and larger (22″) ram point.  The 530 could be equipped with either 54″ jaws (for 48″ piling) or 80″ jaws (for 72″ piling.)  Offshore and onshore specifications are below.

Some general arrangements are below.  The onshore 530 was never built.

The 520 was strictly an onshore hammer, although it could be configured as an offshore one. The first one was sold in 1984 to Jensen and Reynolds Construction Company.  Specifications are above and general arrangements are below.

The 535 was the last in the series to be developed.  It was an offshore hammer but its one and only application (in 1994) was to drive concrete cylinder piles onshore.  On the job, equipment difficulties were manageable by themselves but became disastrous to both the contractor and Vulcan due to mandated overdriving of the hammer. General arrangements and specifications are below.

Photos of the 530 and 535 are below.