Patent Application
20140097960
Embodiments within the present disclosure relate, generally, to systems and methods for preventing improper lifting of tubular members through use of alarms responsive to the weight applied during a lifting operation, the position of a tubular member within a lifting device, or combinations thereof.
When assembling a string of tubular members, such as a drill string or casing string, a lifting device, such as an overshot-type casing running tool, normally in conjunction with an elevator or similar gripping apparatus, is engaged with an individual tubular member, then used to move and/or rotate the tubular member to engage the tubular member with an adjacent portion of the tubular string. The lifting device is then disengaged from the tubular string, and the process is repeated. Similarly, when disassembling a string of tubular members, a single member of a tubular string can be engaged by a lifting device, rotated to disengage the tubular member from the string, then lifted and/or otherwise moved.
Conventionally, when engaging a lifting and/or running tool with a tubular member, one or more individuals on a rig floor and/or one or more other visual indicators are used to provide a signal to an operator when the tubular member reaches the correct position within the lifting device for engagement. If an operator continues to move the lifting device after this position has been reached, an improper engagement can result, and/or the lifting device can forcibly contact the tubular member, causing damage to the lifting device and/or the tubular member.
When performing assembly and/or disassembly operations, operators must repetitively perform a sequence of steps that include engaging tubular members with a lifting device, lifting and/or moving the tubular members, torquing the tubular members, disengaging the lifting device, then repeating the process with subsequent tubular members. Due to the repetitive nature of such an undertaking, it is common for an operator to inadvertently skip one or more of these steps, or to lose awareness of the most recent action that was performed. Incomplete torquing of a tubular connection during disassembly can also create difficulty. As a result, it is possible to exceed the maximum lifting capacity of a lifting device by inadvertently attempting to lift multiple connected tubular members at one time. While some systems include visible signals that are provided when an improper lifting operation is undertaken, these signals are often overlooked, especially during situations in which the initial error resulted from operator inattention.
For example, during casing running procedures, a single common load is handled by two operators: a driller responsible for the rig, and the operator of the casing running tool. During casing running operations, the load must be transferred from an elevator or similar lifting apparatus having a limited capacity to the casing running tool. If any miscommunications occur between operators, or if any operations are performed improperly, loads exceeding the capacity of the equipment can be inadvertently applied.
A need therefore exists for systems and methods for preventing improper lifting of tubular members that instantly and effectively alerts operators, and other personnel at a work site, before damage can be incurred through an improper lifting operation.
In the detailed description of various embodiments useable within the scope of the present disclosure, presented below, reference is made to the accompanying drawings, in which:
One or more embodiments are described below with reference to the listed Figures.
Before explaining the described embodiments useable within the scope of the present disclosure in detail, it is to be understood that the present invention is not limited to the particular embodiments described herein and that the present invention can be practiced or carried out in various ways.
Embodiments described herein relate to alarm systems and methods for preventing improper lifting of tubular members, and particularly audible alarm systems.
In one embodiment, an audible alarm system can be used in conjunction with a lifting device usable to engage and maneuver a tubular member. For example, a casing running tool, such as the CRT-350, produced by National Oilwell Varco, can be provided for engagement with and assembly or disassembly of one or more segments of casing. While any type of lifting device is usable within the scope of the present disclosure, in an embodiment, the lifting device can include an internal bore for receiving the tubular member, and a slip or similar gripping member for engaging the tubular member once it is received and properly positioned within the internal bore.
A sensing device can be disposed within the internal bore or otherwise secured to the lifting device, for detecting the tubular member when the tubular member achieves a selected position suitable for engagement by the lifting device. For example, the tubular member can contact a mechanical member positioned within the lifting device. Alternately or additionally, a laser device, electronic position sensor, motion detector, or similar device known in the art can be used to determine when the tubular member reaches a selected position relative to the lifting device.
Responsive to detection of the tubular member by the sensing device, an audible device, such as a pneumatic horn and/or an air horn, can be actuated to produce an audible sound, to immediately alert the operator of the lifting device, and/or other personnel at a work site. It should be appreciated that other types of alarm devices are also readily usable with various embodiments of the present invention, such as by way of example, lights. Continued motion of the lifting device can thereby be immediately ceased, preventing improper contact between the lifting device and the tubular member, an improper engagement therebetween, or other potential sources of damage.
Once the lifting device has been engaged with a tubular member, one or more operators, such as for example a cylinder, secured to or otherwise provided in operative association with the lifting device can also be engaged with the tubular member. Thus, when a lifting operation is performed, the weight of the lifting operation is applied to the operator. For example, two fluid and/or gas cylinders, which can include hydraulic or pneumatic cylinders, can be provided on opposing sides of the lifting device, or alternately, a spring or other mechanical biasing member can be used. A collar, single joint elevator, or similar gripping device secured to the one or more operators can be placed around the tubular member. The cylinders or other operators can be provided with a preselected force and/or a known load corresponding to the weight of a single tubular member, the maximum weight capacity of the lifting device, or the maximum weight capacity of an elevator or spider used in conjunction therewith.
When a lifting operation is performed, the weight of the tubular member is first provided to the one or more operators. The preselected force of the one or more operators resists the weight of the lifting operation, such that if the weight of the lifting operation is less than the preselected force, the lifting operation can occur uninterrupted. If the weight of the lifting operation exceeds the preselected force, which can readily occur if multiple connected tubular segments are inadvertently lifted, an audible device, such as an air horn and/or a pneumatic horn, engaged with the operator, can provide an audible alarm to alert the operator of the lifting device and/or other personnel at the work site. The improper lifting operation can thereby be immediately halted before damage is incurred to the tubular members or lifting equipment.
Referring now to
A first operator (14) and a second operator (16) are shown secured to opposing sides of the lifting device (10). The first operator (14) is also secured to the tubular member (12) using a first pivotable arm (20), which is engaged with a collar (18) that is disposed about the tubular member (12). Similarly, the second operator (16) is shown secured to the tubular member using a second pivotable arm (22) secured to an opposing side of the collar (18). During typical operations, the collar (18) can include any manner of gripping and/or lifting device, including without limitation a single joint elevator or other type of elevator, a spider, a tong, or other similar devices.
The operators (14, 16) are shown as fluid cylinders, which can include hydraulic, pneumatic, and/or other fluid or gas cylinders, as known in the art, enclosed within a movable housing, which is described in greater detail below. The operators (14, 16) can be adjustable or otherwise able to be provided with a preselected force, or alternatively, the operators can have a known load and/or force, such that when weight is applied to the operators (14, 16) during lifting of the tubular member (12), if the weight exceeds the preselected force or known load of the operators (14, 16), the movable housing will be pulled toward an extended position, and an internal or external sensor (not shown) will be actuated. It should be understood that the sensor within or otherwise associated with the operators (14, 16) can include any manner of contact switch, position detector, electric, hydraulic, pneumatic, or mechanical switch or detector, or combinations thereof, as known in the art. An audible device (24), shown as an air horn, can be provided in operative communication with the sensor, such that responsive thereto, the audible device (24) will produce an audible alarm to attract the immediate attention of the operator and/or other personnel at a work site.
For example, the preselected force and/or known load of the operators (14, 16) can correspond to the weight of a single tubular member, such that if a single tubular member is lifted, the preselected force is not exceeded, and the sensor within or otherwise operatively associated with the operators (14, 16) is not actuated. However, if multiple connected tubular members are inadvertently lifted, the preselected force will be exceeded, causing the sensor to actuate the audible device (24), such that the improper lifting operation can be immediately halted.
Referring now to
Referring now to
However, due to the possibility that a user may inadvertently maneuver the lifting device (10) and/or the tubular member (12) after the tubular member (12) reaches a position suitable for engagement, potentially causing an impact between the lifting device (10) and the tubular member (12), and/or allowing for an improper engagement, the system can also include a sensing device (not visible in
Referring now to
An operator (14) is also shown engaged to the lifting device (10), as described previously, the operator (14) being operatively connected to a single joint elevator (32) or similar lifting device by a pivotable arm (20). A sensing device (36) is disposed on the operator (14) for determining when a weight applied to the operator (14) during lifting of a tubular member engaged by the lifting device (10) and/or the single joint elevator (32) exceeds a preset force or known weight of the operator (14). Responsive to output from the sensing device (36), an audible device (24) can provide an audible alarm when the preselected force of the operator (14) is exceeded, as described previously, such that an operator can immediately halt an improper lifting operation that could potentially damage the tubular member, lifting device (10), single joint elevator (32) or other equipment.
Each of the depicted audible devices (24, 34) can include separate pneumatic and/or air supplies, and can produce sounds that are readily able to be differentiated, such that operators and/or other individuals at a work site can remain contemporaneously aware when a tubular member reaches a selected position within the lifting device (10) and/or when a lifting operation that exceeds the preselected force of the operator (14) is initiated.
While various embodiments useable within the scope of the present disclosure have been described with emphasis, it should be understood that within the scope of the appended claims, the present invention can be practiced other than as specifically described herein.
