Port crane: purpose, description, modifications

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Having been in any port city, paying attention directly to the port, you can always see the so-called port crane on the horizon. Without these lifting machines, it is simply unrealistic to imagine not only sea or river "gates", but also the construction site of hydraulic structures, shipbuilding enterprises. We will talk about these units in more detail in the article.

Marking

Let's note right away that the expression "port crane" is not completely correct, since cranes of a wide variety of systems and types can be used in the port. The correct phrase would be "portal crane", the name of which comes from its based structural element - the portal.

Port gantry cranes have the following designations:

• The K stands for faucet.
• "P" - portal.
• D/M/P - dock, assembly, reloading.
• K/G - hook, clamshell (these letters refer to the old designation system).

The meaning of the numerical indices is:

• 1 is the maximum capacity on the main hook or at maximum reach.
• 2 - maximum departure.
• 3 – gauge of the portal.

Whenthe carrying capacity will be different depending on the departure, the designation of the departure itself and the carrying capacity indicator occurs in two digits - through a fraction.

Responsibilities

Now consider port cranes depending on their purpose:

Overload. This is the most popular type of port loaders. Its carrying capacity ranges from 5 to 30 tons. A grab (for loose materials), a magnetic washer for reloading scrap metal or a hook suspension for piece cargo can be used as a load gripping body

• Mounting is most often used in shipbuilding and ship repair yards, in ports. Its body is almost exactly the same as that of the reloading "brother", and the difference lies only in the presence of a gooseneck on the trunk. It is also characterized by a low speed of movement of the hook. There can be two traction winches (for the main and auxiliary lifting). Load capacity ranges from 12.5-60 tons.
• Slipway - this is perhaps the smallest type of portal units. In fact, it is an assembly machine, which has found its application only in enterprises involved in the construction of various ships. A characteristic feature of the crane is a high portal and a trolley-type current lead. Able to hold a load close to the maximum carrying capacity for a very long period of time (assembly of the hull of ships takes more than one day). Load capacity is 30-160 tons.
• Dock. This harbor crane, due to itsthe specifics of the work has a very small carrying capacity. Of the design features, it is worth highlighting a narrow portal and the presence of anti-theft grips (in addition to rollover protection). Also, the operation of the mechanism is limited by the degree of excitement of the sea or river.

Main structural elements

Port cranes in most cases consist of the following basic parts:

• Portal. Its main purpose is to reduce the mass of counterweights by increasing the platform. Due to this design of the center of gravity, the possibility of overturning of the crane is excluded. In addition, between the legs of the portal, a rail or road transport pass is carried out. It also allows the crane itself to pass over any structure.
• Leg - part of the portal, the bottom of which ends with carts (driven or idle).

• Head of the portal. It connects the legs. In addition, it perceives the loads from the turning part. The electrical equipment of the crane movement mechanism is installed in the head.
• Slewing ring.
• Power supply.

Technical data

Port cranes, the characteristics of which may vary, are generally produced and operated taking into account the following indicators:

• Capacity.
• Arrow reach and rate of change of its reach.
• Crane travel speed.
• Turn speed.
• Wheel load indicator.
• Trolley travel speed (if any)available).

Also, when studying a port crane, special attention must be paid to the mechanism for changing the boom reach, which, in turn, can be of a hydraulic, rod, pulley or crank type.