Elevator manufacturers can offer a variety of different drive elevators. Now, Elevator Manufacturers Fuji takes you through the difference between hydraulic and traction elevators.
The hydraulic lift pumps hydraulic oil to the cylinder/plunger assembly, causing the piston to move vertically, moving the lift up and down. Conventional cylinder/plunger assemblies are located in the wellbore directly below the elevator, and many years ago these components were installed with little or no protection for underground components. If the parts on the lower surface cannot be inspected, the damage to the hydraulic cylinder that eventually causes the hydraulic oil to leak will be ignored. When this happens, it usually causes soil and groundwater pollution.
Any maintenance contract does not include maintenance of the elevator. The cost of the cylinder/plunger assembly (including the required contaminant repair) can be as low as $30,000 and in some cases can exceed $100,000.
Keep in mind that hydraulic elevators need to be provided in a controlled environment where additional heating is required, and in some cases air conditioning is required. Remote pipelines operating underground are another potential problem for temperature control and potential leaks.
The traction lift is driven by a machine that includes a steel sling that rides on a drive pulley and is typically attached to a counterweight assembly and a car crosshead. For overhead traction elevators, you need to provide a top floor structure that surrounds the elevator equipment and supports the elevator load. MRL elevator equipment is usually mounted on rails and transfers loads to elevator pits. MRL elevator designs typically have lower overhead requirements and allow designers to provide the desired smoother roof line appearance.