MARINE CRANES Regulations, tougher operating conditions drive crane design
Michael R. Slaton Contributing Editor Titan Industries 12,000-B modular deck crane lifts a 33-ton load in yard tests. Table: Deck Crane Survey - 1995. The following [table] is a compilation of some of the deck based lifting equipment offered by major manufacturers in the marine crane business. This listing attempts to provide an initial base for comparing the various models on the market, but because of customization, the survey does not represent a complete or comprehensive listing.
Offshore deck crane cost and complexity growing
Michael R. Slaton
Titan Industries 12,000-B modular deck crane lifts a 33-ton load in yard tests.
- Table: Deck Crane Survey - 1995. The following [table] is a compilation of some of the deck based lifting equipment offered by major manufacturers in the marine crane business. This listing attempts to provide an initial base for comparing the various models on the market, but because of customization, the survey does not represent a complete or comprehensive listing.
Building a marine crane is getting more complicated and more expensive. Manufacturers say world markets are adding technology, a wider range of operating conditions and layers of regulations to crane design and construction.
Simply working in the world market means dealing with a wide and sometimes perplexing variety of regional, national and institutional standards and regulations. That overhead adds to the cost of a crane.
Computerized systems for monitoring crane lifts, higher strength steels and new modular designs add sophistication and capabilities but at a cost. Building cranes to operate across a world-wide range of environmental and operational conditions often requires the added expense of customization. Modifications due to the customer's own standards and practices also adds expense, say manufacturers.
While crane prices appear to be headed up, used cranes sales may also be growing. One manufacturer, who notes a growing trend in used equipment sales over the last year, cautions that safety and economics are not always best served by acquiring such a critical component on the used market.
"In general, the regulatory bodies have created a nightmare for crane manufacturers," says Robert Bray, deck crane manager for Manitex of Georgetown, Texas. "The market dictates that as a manufacturer you have to be a world player. This requires knowing all the rules of API, ABS, Lloyds, DnV, PSLA, HSE, and a host of others."
Manufacturers also have to keep up with a dynamic situation. Rules change. Lately, the crane industry has been adapting to API revisions this summer for Specification 2C, "Specifications of Offshore Cranes," and Specification 2D, "Recommended Practice for operations and Maintenance of Offshore Cranes."
Customers often add their own special requirements to the mix, says Bray. Some examples include inspection hold points, paint requirements and tests, special welding, heat treating and steel composition. The problem is compounded if the customer is a consortium of engineering firms and oil companies.
"All this is neatly wrapped into a 500-page specification for a single crane which may sell for a half million dollars." Building a crane is getting to be a more expensive business, says Bray.
Meeting the design and specification standards of the international market is also an expensive process. Sophisticated load/moment indicator systems are becoming more prevalent in the cranes being supplied to the world market, says Bray.
Operator comfort has become a major factor with ergonomic designs to help reduce fatigue and stringent noise control in the operator cab. High pressure, piston-operated hydraulic drives are being employed for greater efficiency and less noise. All of this means that the price of cranes must inevitably increase, says Bray.
However, operators may be searching for ways to keep costs down. "In the past, international energy companies have been very prescriptive in their crane specification requirements," points out Alan Schaefer of Weatherford's American Aero Cranes.
"One company has begun evaluating alternatives to cut equipment, project, and operating costs," Schaefer said. "The intent is to no be as prescriptive with the crane specifications. Basic requirements will be supplied and vendors will be allowed to propose their standard crane most closely meeting the requirements.
"This move is a result of prior project specifications being too detailed and the resulting equipment purchased was costly and extended service life was not realized. Hence, the associated cost to maintain did not justify the extra expense in meeting the specialized requirements," he added.
Addressing the market
Crane manufacturers are responding to market demands in many ways, including new designs and technologies and through new methods such as quality control programs.
Gary Hutchinson, sales administrator for Applied Hydraulics Systems of Houma, Louisiana, says the general challenge of today's market is to design a product line which has higher dynamic lifting capacities with lower initial cost, lower maintenance cost and higher safety factors.
The company is using higher strength steels for box boom cranes in order to reduce the crane dead weight while still increasing lift capacity. And it is employing new methods and adding capabilities. Applied Hydraulic Systems was recently awarded ISO 9001 certification and has enhanced its quality control and production time with the addition of a machine shop that provides new in-house capabilities.
Titan Industries, Covington, La., recently unveiled and tested the first of three 150,000-lb lift capacity units for Sundowner, a Nabors Industries operating unit. The first crane is slated for installation on new generation modular platform drilling rig to be operated offshore Trinidad for the Dolphin Field development project, a joint venture of British Gas and Texaco.
The Titan 12,000-B, one of the company's largest cranes, is a modular package designed for easy relocation, but stout enough to handle the harsh environment conditions in which it will be employed.
Manitex recently completed two new designs to round out the top end of its product line, says Steve Griffin, sales coordinator. The company's ML-7200 is rated at 185,000 lb static at 30 ft radius with 100-ft boom and the ML-10000 is rated at 220,000 lb static at 30-foot radius with a 100 ft boom. Two 7200 cranes were delivered in September to Bollinger Shipyard and installed on Halliburton's new service vessel, the Irish Sea Pioneer.
At EBI Techcrane in Houston, Fahad Shad says that the cost of new cranes is causing some large and small operators to acquire used cranes for marginal platforms. The trend has grown in the last year.
The economics of keeping older facilities in operation is supporting a growing trend in the use of used equipment, says Shad. But buying used equipment for something as critical as a crane can be a false economy in several ways, including safety, the potential downtime and loss due to a simple or catastrophic failure, and the cost of refurbishing and operating a used crane versus a new one.
Some of these cranes are 10-20 years old, says Shad. Their history and the kinds of lifts they have made is unknown. With some of the older models, the manufacturer may no longer be in business, specifications may not be available, and component replacements may only be available used or not at all.
The short term savings afforded by buying a used crane is minimal in some cases, says Shad. "On a 30-ton crane, it may be as little as 10%. True refurbishment is expensive due to replacement of parts, rewelding, disassembling and inspecting... it's a very labor intensive process. It can take longer to do than building a new crane."
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