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[IMAGE]MET11Lifts.jpg[/IMAGE]Vehicle lifts enable service technicians or mechanics to work under vehicles with ease. There are many types of lifts available, but due to restrictive environmental laws and new technologies, the popularity of lift types has swung from one side of the spectrum to the other and, perhaps, back again.
The first types of vehicle lifts, designed for cars, were in-ground, single-post lifts that required excavation and significant investment to install. These lifts use hydraulic oil and attach to the axle of the car, leaving the wheels free.
In-ground lifts were the most popular types of lifts for about half a century, but with increasing environmental awareness in the 1980s, they were attacked as being harmful to the environment, as hydraulic oil buried underground sometimes leaked into the water supply. According to Roger Perlstein, director of heavy-duty lifts for Rotary Lift Inc., in Madison, Ind., "The EPA was being aggressive about the impact of petroleum products on the environment and on ground water. People who had lifts in the ground found they were contaminating the ground and potentially the drinking supplies of surrounding neighborhoods."
Significant technological improvements have been made in recent years that have reduced the negative environmental impact of in-ground lifts. Today, many types of lifts are available, including multi-post runway, mobile, parallelogram, scissor, in-ground and surface-mounted.
Steve Perlstein, sales and marketing manager for Mohawk Lifts, based in Amsterdam, N.Y., emphasizes that having the right type of lift makes a big impact on the safety and productivity of technicians as well as the safety of the vehicles being lifted. Each type of lift has its advantages and disadvantages, and Mohawk offers both in-ground and surface-level lifts. However, Perlstein says the wide variety of styles, types and capacities of surface-mounted lifts make them more popular for Mohawk transit clients.
One of the reasons surface-mounted lifts are popular is the environmental factor. While above-ground lifts also use hydraulic oil, leaks above ground are more easily detected and taken care of. Perlstein says if an underground leak results in contaminating the ground soil, the agency is then responsible for cleaning it up, a costly process. "In an above-ground lift, if any oil that was in a lift ever leaked, it's on top of the concrete floor," he says, which is easy to see and clean. In addition, being able to fix the leak is much easier if it is easier to access. "There's no tearing up of concrete to diagnose what the problem might be," he adds.
Perlstein explains that surface-mounted lifts may last longer because of possible complications with ground water seeping into the steel of the hydraulic cylinders buried in-ground.
Also, price estimates for an in-ground lift are always significantly more expensive than above-ground lifts, usually due to the installation process involved for an in-ground lift. Perlstein says above-ground lifts do not require a compressor, but instead run on an electric motor.
Mohawk's mobile column lifts are the least expensive option in its lift offerings and, according to Perlstein, an MP-18 would be sufficient for most transit vehicles. The columns sit above ground, require little to no installation and lift the vehicle from its wheels. Adjustable, long lifting forks grab both the inner and outer tire and can accommodate a wide range of wheel sizes. An MP-18 column has the lifting capacity of 18,000 pounds.
A simple control system, with just the necessary options (up, down, park), make controlling the lift easy.
MP-18 safety features include 19 safety lock positions spaced every three inches starting at 12 inches, locking pins that prevent the movement of the adjustable lifting forks and low-mounted power units for easier-to-move columns. A manual safety override allows columns to be lowered in a power outage without using hand cranks. A weight gauge reads how much weight the hydraulic pressure is holding, which helps ensure that mechanics use the safety locks.
For smaller paratransit vehicles, Perlstein recommends the TP-16, a two-post lift with 16,000-pound capacity. Unlike the mobile columns, this surface-mounted lift is attached to the ground. Hydraulic fluid is pumped between the two cylinders through the overhead steel hydraulic lines, which are synchronized and can be set at any height to accommodate for tall vehicles. Five-inch low-profile swing arms fit under most cars. According to Mohawk, the self lubricating steel ball bearing rollers that it uses last longer than plastic slide blocks.
The cost of four MP-18 mobile column lifts is about $30,000, while the TP-16 is about $13,000
Rotary Lift's Roger Perlstein says in the last five years, he has seen resurgence in the popularity of in-ground lifts due to improving technology that has taken away the environmental risks of in-ground hydraulic lifts.
One of the advantages of the in-ground lift is its physical footprint. With the hydraulic system buried underground, only a piston rises that clamps to the axle of the vehicle. According to Perlstein, the railroad-like track or runways of most above-ground lifts require more space to store and operate, meaning that an agency could be using a 15-foot-wide bay to pick up a vehicle that is only eight feet wide.
"The carbon footprint of a transit facility is impacted by the size of its service bays," says Perlstein. The smaller the bay needed, the less heating, lighting, air conditioning and space required for the same service, an important factor to consider in green building design.
Rotary Lift's in-ground MOD30 lift uses the same technology as tanks at modern gas stations. For its in-ground, Rotary uses inert materials that don't react with corrosives and don't conduct electrical current, taking away the environmental hazards. The underground portion is encased in containment housing so that in case of a leak, the fluids are contained. Monitoring and alarm systems also let technicians know if there are leaks. "Now, what we're seeing is a tremendous swing from the alternative design to the in-ground, because they save a whole lot of space, are environmentally more progressive than even the above-ground designs and reduce the carbon footprint," says Perlstein.
The MOD30 can also save technician labor. The fact that in-ground lifts raise vehicles by its axles means that the tires are accessible at all times, important when dealing with vehicles that drive in urban environments with more road hazards. With the MOD30, everything can be easily accessed and serviced quickly.
Its most popular mobile column lift, the MACH4, is faster to use and easier to install, but does lift the vehicle by its wheels. Its ease of use makes it convenient for some maintenance procedures but, to do work on tires, a technician would need to put a jack stand underneath the bus and lower it onto the jack stand to take off the tires and pull the columns out of the way, a process that could add up to significant loss of employee time, according to Perlstein.
However, it takes more time to position the in-ground pistons to match the axles of a vehicle than it does to use simple, drive-in mobile columns. In order to maximize technician time, the type of lift used should be based on the type of service being performed.
Perlstein says many agencies choose a combination of lift types for their various needs. "There isn't a single design out there that's perfect," he says. "Every one of them, to some degree, forces its user to make some sacrifice." A smaller transit facility may choose only mobile columns, but usually larger agencies will have both, and other designs as well.
Rotary's MOD30 is estimated at $100,000 to $160,000 installed and $30,000 for a four-column MACH4 set.