MULTI FUNCTION HEAVE COMPENSATOR

摘要

A heave compensator with adjustable dampening properties includes a length extension device having an inner space divided by a slide-able piston into a vacuum chamber and a liquid filled chamber, a gas accumulator divided by a slide-able piston into a gas filled chamber and a liquid filled chamber, and a gas tank having an expansion chamber. The liquid and gas chamber are fluidly connected to each other with valve controlled conduits. Further, the device includes pressure and temperature sensors that register pressure and temperature in the gas and liquid phases. The device further includes a control unit having a signal receiving unit, a writeable computer memory, a data processing unit, and a signal transmitting unit. The data processing unit contains computer software that calculates suited amounts of gas and gas pressure in the gas accumulator and/or gas tank based on the information of which lifting operation is going to be performed. The data processing unit further engages activation means such that the suited amount of gas and gas pressure are achieved and maintained during the different phases of the lifting operation.

主权项

1. A device for compensating for heave movements between a lifting device and a load lifted by the lifting device, the device comprising:
an elongated length extension device comprising:
a closed upper end;a lower end having an opening for a piston rod and a liquid outlet;an inner space divided by a slide-able first piston into an upper vacuum chamber and a first lower liquid filled chamber;a piston rod of length at least equal to the length of the length extension device, wherein a first end of the piston rod is attached to the first piston, and wherein the piston rod stretches through the first liquid filled chamber and further out through the opening in the lower end of the length extension device;means arranged at a second end of the piston rod for releasable attachment of the load; andmeans arranged at the upper end of the length extension device for releasable attachment of a lifting device; an elongated cylindrical gas accumulator comprising:
an upper end having a first adjustable gas outlet, the first adjustable gas outlet having a first valve;a lower end having a liquid outlet; andan inner space divided by a slide-able second piston into an upper chamber and a second lower liquid filled chamber, an adjustable liquid transferring device fluidly connected to the liquid outlet of the lower end of the length extension device and the liquid outlet of the lower end of the cylindrical gas accumulator, the adjustable liquid transferring device having a second valve; activation means for selective opening or closing of one or both of the first valve and the second valve; a first and second measuring means for measuring a temperature and/or pressure of the liquid in at least one of the first lower liquid filled chamber and the second lower liquid filled chamber and the gas in the upper chamber of the cylindrical gas accumulator, respectively; a third measuring means for measuring the position of the first piston; and a control unit comprising:
means for registering the measured temperatures and/or pressures of the liquid in one of or both of the first lower liquid filled chamber and the second lower liquid filled chamber, the gas in the upper gas filled chamber of the cylindrical gas accumulator, and the position of the first piston;means for calculating a real equilibrium position of the first piston from the registered temperatures and/or pressures and the registered positions of the first piston;means for calculating an amount of gas that needs to be ventilated out of the first adjustable gas outlet in order to obtain an intended equilibrium position of the first piston; andengaging means for engaging the activating means of the first valve and/or the second valve such that the intended amount of gas exits through the first adjustable gas outlet and such that the first piston obtains the intended equilibrium position.