Abstract: Downhole drilling vibration analysis uses an angular rate sensor on a drilling assembly. During drilling operations, the sensor measures the angular rate of the drilling assembly. Processing circuitry is operatively coupled to the angular rate sensor and is configured to determine whether torsional type vibrations are occurring during drilling based on the angular rate data. Drilling operations can then be modified to overcome or mitigate the torsional type vibrations.

Abstract: A downhole drilling vibration analysis involves measuring orientation data in at least two orthogonal axes downhole while drilling with a drilling assembly. For example, two orthogonal magnetometers can be used. A toolface of the drilling assembly is determined using the measured sensor data, and velocity (RPM) values for the toolface for a plurality of revolutions of the drilling assembly are determined. From these determined values, a coefficient of variation for the toolface velocity (RPM) values for the revolutions of the drilling assembly is calculated. When a pattern in found in the toolface velocity (RPM) and/or the calculated coefficient of variations exceed one or more thresholds, the processing device determines that detrimental vibrations are occurring in the drilling assembly.

Abstract: A downhole drilling vibration analysis involves measuring orientation data in at least two orthogonal axes downhole while drilling with a drilling assembly. For example, two orthogonal magnetometers can be used. A toolface of the drilling assembly is determined using the measured sensor data, and velocity (RPM) values for the toolface for a plurality of revolutions of the drilling assembly are determined. From these determined values, a coefficient of variation for the toolface velocity (RPM) values for the revolutions of the drilling assembly is calculated. When a pattern in found in the toolface velocity (RPM) and/or the calculated coefficient of variations exceed one or more thresholds, the processing device determines that detrimental vibrations are occurring in the drilling assembly.

Abstract: There is described a crushing plant and a method for controlling the same. The crushing plant involves a gyratory crusher (1) with means for controlling a minimum gap in a crushing chamber, and is driven by a diesel engine (18). A load value is retrieved from the diesel engine e.g. by means of a J1939 interface. If the retrieved value exceeds a predetermined threshold value, the minimum gap is increased. Thereby it can be avoided that the diesel engine stalls; such that continuous operation of the crushing plant may be ensured.

Abstract: A downhole drilling vibration analysis involves measuring orientation data in at least two orthogonal axes downhole while drilling with a drilling assembly. For example, two orthogonal magnetometers can be used. A toolface of the drilling assembly is determined using the measured sensor data, and velocity (RPM) values for the toolface for a plurality of revolutions of the drilling assembly are determined. From these determined values, a coefficient of variation for the toolface velocity (RPM) values for the revolutions of the drilling assembly is calculated. When a pattern in found in the toolface velocity (RPM) and/or the calculated coefficient of variations exceed one or more thresholds, the processing device determines that detrimental vibrations are occurring in the drilling assembly.

Abstract: There is described a crushing plant and a method for controlling the same. The crushing plant involves a gyratory crusher (1) with means for controlling a minimum gap in a crushing chamber, and is driven by a diesel engine (18). A load value is retrieved from the diesel engine e.g. by means of a J1939 interface. If the retrieved value exceeds a predetermined threshold value, the minimum gap is increased. Thereby it can be avoided that the diesel engine stalls; such that continuous operation of the crushing plant may be ensured.

Abstract: An inner shell, which is intended for use in a gyratory crusher and which during crushing will rotate around its own center axis in a first direction, has at least one additional crusher surface. The additional crusher surface has, in horizontal projection and as seen in the first direction, a decreasing distance to the center axis. Large objects can be introduced between the additional crusher surface and an outer shell near a first end of the additional crusher surface in order to, near a second end of the additional crusher surface, be squeezed between the additional crusher surface and the outer shell and be crushed.

Abstract: An inner shell, which is intended for use in a gyratory crusher and which during crushing will rotate around its own center axis in a first direction, has at least one additional crusher surface. The additional crusher surface has, in horizontal projection and as seen in the first direction, a decreasing distance to the center axis. Large objects can be introduced between the additional crusher surface and an outer shell near a first end of the additional crusher surface in order to, near a second end of the additional crusher surface, be squeezed between the additional crusher surface and the outer shell and be crushed.

Abstract: A crusher includes a replaceable first crushing member having a first crusher surface and a replaceable second crushing member having a second crusher surface. The co-operation of the crusher surfaces is defined by at least one crusher setting parameter. From measurements of a quality parameter, which relates to the nature of the crushed material, on at least two different occasions during the service life of a set of replaceable first and second crushing members and on each occasion for at least two different settings of the crusher setting parameter, a control function can be determined that describes a value, of the at least one crusher setting parameter, which on a given occasion gives a crushed material the quality parameter of which is substantially optimal.

Abstract: A crusher includes a replaceable first crushing member having a first crusher surface and a replaceable second crushing member having a second crusher surface. The co-operation of the crusher surfaces is defined by at least one crusher setting parameter. From measurements of a quality parameter, which relates to the nature of the crushed material, on at least two different occasions during the service life of a set of replaceable first and second crushing members and on each occasion for at least two different settings of the crusher setting parameter, a control function can be determined that describes a value, of the at least one crusher setting parameter, which on a given occasion gives a crushed material the quality parameter of which is substantially optimal.