For over 70 years, Metro Hydraulic Jack Company, a third-generation, family-owned and operated business, has been providing industrial hydraulic parts and equipment services to commercial, automotive, marine, refuse, and construction industries.More About Our Company
Mechanical Jacks vs. Hydraulic JacksWhat is the difference between a mechanical jack and a hydraulic jack? With the number of jack types that are available, it is important to understand the difference between the two. Additionally, each type of jack offers its own benefits and drawbacks. Knowing which jack type to use involves understanding the differences in the two types of lifting devices.
Mechanical JacksIn contrast to hydraulic jacks, mechanical jacks use only physical means of raising and lowering their loads. Using mechanical advantage, these jacks are commonly seen in the automotive industry for lifting vehicles and other loads. A common type of mechanical jack is known as a “screw jack.” With the use of a motor, or a lever that is cranked by an operator, a screw uses the shape of its threads to raise or lower the jack. Depending on the type of jack, the screw itself may raise or lower the load, or a traveling nut does the raising while the screw turns in place. These jacks have many applications that include moving platforms on stages, changing settings on woodworking machinery, and adjustments of radio telescopes. Other applications also involve the use of mechanical jacks and they provide some advantage over hydraulic systems. Mechanical systems are normally self-locking. This means that when power is removed from the jack, the screw remains in the same position until power is reapplied. Self-locking properties make these jacks safer to use than hydraulic units, since operators need not worry about loss of power. Drawbacks of a mechanical system include the fact that they are not capable of lifting the same loads as hydraulic lifts. Additionally, levers that provide mechanical advantage for manual operations can only reach a certain length before bending and becoming useless.
Hydraulic JacksHydraulic jacks apply force through hydraulic cylinders to lift heavy loads. This makes them instrumental to many industrial, construction, storage, and shipping processes. Because hydraulic jacks play such an important role in lifting heavy objects, finding the right system for your needs is essential to creating a well-running facility. We at Metro Hydraulic Jack Co. know a thing or two about hydraulic jacks—we’ve been delivering hydraulic lifting systems for nearly 80 years! We design jacks capable of lifting loads as heavy as 200 tons, and our team of experts is willing and eager to find the best lifting system for your facility.
How Do Hydraulic Jacks Work?Hydraulic systems operate based on the principle that pressure applied to a fluid in a closed system distributes equally to all points of the system’s volume. For our purposes, this means that any force applied to a closed hydraulic system gets multiplied throughout that system as it compresses, generating a much stronger lifting motion than other applications that apply force directly to the object being lifted. To describe this process in more detail, hydraulic jacks operate via the following procedures:
- A pump plunger moves oil through two cylinders, creating pressure
- The system pulls the pump plunger back, causing the suction valve to draw oil into the pump chamber
- The system pushes the plunger down again, transporting oil through an external discharge valve and into the cylinder chamber
- The suction valve closes, which causes pressure to build within the chamber
- The pressure buildup causes the piston to rise, lifting your heavy object
Types of Hydraulic JacksHydraulic jacks usually take one of two forms:
- Bottle jacks are vertically mounted systems that push weight upwards. Their straightforward design allows them to lift heavy loads within compact spaces, but since they’re smaller and narrower than floor jacks, they offer less stability for wide or unwieldy loads.
- Floor jacks are horizontal cylinders that lift weight parallel to their power source. Many floor jacks sit low to the ground, allowing operators to insert them into tight spaces and also to mount them on tractors and crawlers. However, because of their bulky design, they’re hard to effectively operate in close quarters.
Providing Quality Hydraulic Jacks for Almost 80 YearsSince 1941, Metro Hydraulic Jack Co. has led the field in supplying quality hydraulic lifting systems to clients across the country. Our full line of hydraulic jacks, tools, and add ons benefit a diverse range of industries. We offer products including:
- Mechanical jacks
- Hydraulic cylinders
- Hydraulic pumps
- Air jacks
- Material handling equipment
- Hydraulic lifts
- Construction equipment
- Heavy cranes
- Automotive manufacturers and car shops
- Earth-moving equipment
- Power equipment
- Material-handling equipment
- Lifting platforms
- Aerospace manufacturing and assembly
- Thermal power plants
- Waste removal
- Mining applications