Apparatus and method for providing a fluid sample in a well

A system for collecting a well sample from a well, comprising:

• a sampling device comprising a measuring device provided with at least one sensor;
• and
• an apparatus configured to bring a well-fluid sample in a well through the sampling device, wherein the sampling device is in fluid communication with the apparatus, and wherein the apparatus comprises:
• a dump chamber for receiving the well-fluid sample;
• a first hydraulic piston arranged in a first cylinder housing;
• a second hydraulic piston arranged in a second cylinder housing;
• a piston rod for mechanically connecting the first piston to the second piston to form a piston arrangement, characterized in that the dump chamber is defined by the first piston and a portion of the first cylinder housing, and that the apparatus further comprises at least one holding device which is arranged to switch between an active position, in which the piston arrangement is held fixed against movement, and an inactive position, in which the piston arrangement is allowed a movement relative to the cylinder housings, said movement of the piston arrangement being brought about by means of a well fluid which, in a position of application, is in fluid communication with the second hydraulic piston so that the movement brings about an increase in a volume of the dump chamber when the holding device is in its inactive position.

A method of bringing a well-fluid sample through a sampling device (3) in a well, comprising:

• providing an apparatus configured to bring the well-fluid sample in the well through the sampling device, wherein the sampling device is in fluid communication with the apparatus, and wherein the apparatus comprises:
• a dump chamber for receiving the well-fluid sample;
• a first hydraulic piston arranged in a first cylinder housing;
• a second hydraulic piston arranged in a second cylinder housing;
• a piston rod for mechanically connecting the first piston to the second piston to form a piston arrangement, characterized in that the dump chamber is defined by the first piston and a portion of the first cylinder housing, and that the apparatus further comprises at least one holding device which is arranged to switch between an active position, in which the piston arrangement is held fixed against movement, and an inactive position, in which the piston arrangement is allowed a movement relative to the cylinder housings, said movement of the piston arrangement being brought about by means of a well fluid which, in a position of application, is in fluid communication with the second hydraulic piston so that the movement brings about an increase in a volume of the dump chamber when the holding device is in its inactive position;
• arranging the dump chamber with a smallest possible volume and then activating the holding device of the apparatus;
• bringing the apparatus together with the sampling device to a desired location in the well;
• and
• initiating movement of the piston arrangement by deactivating the at least one holding device so that a well fluid sets the piston arrangement in motion in order thereby to increase the volume of the dump chamber and suck the well-fluid sample through the sampling device.