WO2024072209A1

WO2024072209A1 - Movable bolting tool for manipulating nut and bolt assemblies of a bolted flange assembly

Info

Publication number: WO2024072209A1
Application number: PCT/NL2023/000009
Authority: WO
Inventors: Martin KRISTELIJN
Original assignee: Intomechanics B.V.
Priority date: 2022-09-26
Filing date: 2023-09-25
Publication date: 2024-04-04
Also published as: NL1044424B1

Abstract

A movable bolting tool comprises a toolhead 3 for manipulating nut and bolt assemblies 11 a-f, 12a-f and a trolley for moving the toolhead 3 along a circumference of a bolted flange assembly 10, which trolley comprises a frame 4 carrying a toolhead supporting assembly 1, 67, 9a, 9b for lifting the toolhead 3 from a manipulated nut and bolt assembly and, after circumferential movement, for engaging the toolhead 3 with a next to be manipulated nut and bolt assembly: wherein the toolhead supporting assembly 1, 67, 9a, 9b is arranged substantially parallel to the substantially vertical lifting direction of the toolhead 3, the toolhead 3 is connected to the toolhead supporting assembly with a pivotable connection 80 allowing rotation about multiple axes; and a toolhead rotation constraining device 95 is arranged at a distance from the pivotable connection 80, and configured to constrain the rotation.

Description

MOVABLE BOLTING TOOL FOR MANIPULATING NUT AND BOLT

ASSEMBLIES OF A BOLTED FLANGE ASSEMBLY

Background of the Invention

The invention relates to a movable bolting tool for manipulating a series of nut and bolt assemblies of a bolted flange assembly. The invention further relates to a method of manipulating a series of nut and bolt assemblies that are distributed along a circumference of a bolted flange assembly using a movable bolting tool according to the invention.

Manipulating a nut and bolt assembly can include, for example, tightening, inspecting, adjusting and/or releasing a nut, which is screwed on a bolt or wire end, also called stud of an already existing bolted flange connection, but aiso one or more steps in the placement of a bolted flange connection at the location of a bolt hole present for this purpose in a perforated flange.

When in the present specification and claims reference is made to a bolted connection it must be understood that, unless explicitly stated otherwise, this term also includes an intended bolt connection, which has not yet been realized, but for which, for example, a bolt hole has already been provided.

Accordingly, when used in this specification and claims, the term manipulating a nut and bolt assembly includes any rotation of the nut relative to the bolt, or bolt relative to the nut, for tightening, untightening and/or re-tightening of the nut and bolt assembly, as well as stretching the bolt.

When used in this specification and claims the terms bolt, and nut and bolt assembly also include assemblies where a nut is screwed on a threaded end of a cylindrical rod or stud which is at another end screwed into a female screw thread in a flange or otherwise rigidly secured to one of the interconnected flanges or components and which rod or stud does not comprise a bolt head that can be clamped and turned by a wrench head, tongue or other mechanical tool head.

Furthermore the terms bolt, and nut and bolt assembly also include assemblies where a pair of nuts is screwed at opposite threaded ends of a cylindrical rod or stud which passes through a pair of aligned bolt holes in adjacent flanges or other components of a mechanical structure.

Bolted connections for interconnecting components of a mechanical structure typically comprise nut and bolt assemblies that are spaced at regular circumferential intervals along the circumference of a circular or curved flange assembly and are generally used to clamp together flanged components of a mechanical structure, such as flanged components interconnecting successive hull parts of a mast, in particular a mast for a wind turbine, transmission tower, oil platform, watchtowers or similar tail structures, or interconnecting successive flanged tubular sections of a pipeline or interconnecting parts of swing bearings of crane housings. These are relatively heavy constructions that often require working in hard-to-reach places to establish, maintain, inspect and/or control the intended bolted connection.

Wind turbines also comprise bolted flange connections between the rotor blades and a central rotor hub that is rotatably connected to a nacelle which is rotatably mounted on a tower to swing the rotor blades towards the wind. The nut and bolt assemblies between the rotor blades and the central hub may be subject to extremely high loads, vibrations and fatigue due to centrifugal loads induced by spinning of the turbine. This requires precise tightening and regular inspection, retightening and replacement of the nut and bolt assemblies.

The nut and bolt assemblies between the wings and a central hub of a wind turbine, and all other nut and bolt assemblies such as between tower or pipeline sections, must be tightened at an accurate prestressing to prevent bolt fatigue. By mechanically checking and electronically registering the tightening process parameters and possibly checking the prestressing of the bolts ultrasonically, a conclusive and traceable registration of each bolt's tightening parameters in the flange connection can be obtained. Human errors such as, for example, skipping a bolt or inaccurate tightening has to be prevented. A more reliable connection assisted by a movable bolting tool also results in cost savings on maintenance because bolt checks can be saved during the service life. In addition, a mechanization of the realization and control of flange connections limits the manpower required to handle the often heavy tools and man-hours can be saved for what will often be repetitive work. Use of a movable bolting tool can therefore save on both installation costs and maintenance costs.

Movable bolting tools are known from European patent specifications EP2607685, EP3163071 , EP3195974, EP3195991 , EP3550139 , International patent applications WO2016193297, WO2019110061 and WO2020/212323, US patent application US2011/232071 , US patents 9,457,439 and 11 ,148,240, Korean patent application KR20130026039 and Japanese patent application JP H01 103240.

The movable bolting tools known from these prior art references generally are heavy and complex devices with complex robot motion mechanisms to move the machine along the circumference of the flanges, which mechanisms need to be adjusted to the curvature of the flanges and to the pitch or circumferential spacing between the circumferentially spaced nut and bolt assemblies.

The known robot motion mechanisms also require electronic positioning and navigation sensors to accurately align the tool head or tool heads with the manipulated nut and bolt assemblies. Such electronic positioning and navigation sensors need regular calibration and are fragile and damage prone components that can easily cause malfunctioning or even inhibit any further utilization of the faulty bolting machine.

For example, the movable bolting tool known from EP 2607685 comprises a robot that allows a series of nuts to be tightened on a corresponding number of bolts of a bolted flange connection of a wind turbine. To this end, the robot is equipped with a drive to feed the robot over the flange connection along a series of bolt nuts and the robot has a tool with which a bolt nut can be tightened with a predefined tightening torque. By means of an optical position sensor, the robot must find its way to position the tool above the bolt nut in question. The position sensor exchanges such position information with a robot control system, which controls the tool and records bolt data.

Although this well-known movable bolting tool thus offers a step forward in further automation and standardization of such a flange connection, the position sensors used therein are sensitive to contamination and disturbance which can lead to wrong positioning of the tool head misaligned with a bolt nut and inhibit any further utilization of the faulty bolting machine. In addition, due to the stability of the applied wagon, the well-known robot device requires that a set of electromagnets from the drive system always together with a complicated roller assembly will be in contact with a wall of the relevant hull segment, which cannot always be achieved in practice.

The movable bolting tool known from US patent 11 ,148,240 and European patent EP3550139 comprises a travel controller to stop a traction drive that moves the rotatable tool head to a next to be manipulated nut and bolt assembly after reaching a predefined travel length along the circumference of a flange, which length is a target variable and the positioning accuracy is dependent on awheel, which may slip or be lifted from the flange if the flange has an irregular or slippery surface. In such case this known travel controller does not accurately align the tool head with the to be manipulated nut and bolt assembly and the tool cannot tighten the nut and bolt assembly.

The movable bolting tool known from WO2020/212323 comprises a tool head that can be maneuvered into alignment with a to be manipulated nut and bolt assembly by a lift and swing mechanism, on the basis of navigation and positioning data acquired by electronic navigation and positioning sensors, which are fragile and require frequent maintenance, inspection, recalibration and replacement.

This known movable bolting tool comprises a tool head lifting crane with a vertical tower that is clamped around a nut and bolt assembly and a curved crane arm with a guide rail from which the tool head carrier body and tool head are suspended, such that they can be lifted up and down to move the tool head from an already tightened to a nearby nut and bolt assembly that is to be tightened. This crane arm and guide rail have a curvature which has to be identical to the curvature of the ring of circumferentially spaced nut and bolt assemblies. If this known robot is to be used to manipulate nut and bolt assemblies that are arranged in a ring with another curvature, then the crane arm needs to be replaced by another arm with a guide rail that also has this other curvature.

This known crane is also a relatively tall structure since the tool head carrier body and tool head are suspended below the arm and need to be lifted up and down to successive nut and bolt assemblies that are to be manipulated.

European patents EP3195974 and EP3195991 disclose movable bolting tools with guide rails that slide along opposite sides of already tightened nut and bolt assemblies and a chain wheel that rolls over these assemblies to monitor the circumferential position of the tool head. The tool head has a frusto-conical alignment section that is lowered onto a to be manipulated nut and bolt assembly when the rotation of the guide wheel indicates that the tool head is located in the vicinity of the to be manipulated nut and bolt assembly. A disadvantage of these known robotic bolting machines is that the distance between the guide rails and their orientation needs to be adjusted to different sizes and radii of nut and bolt assemblies and that the guide wheel needs to be replaced by a differently dimensioned guide wheel if the radii of and/or pitches between and/or sizes of adjacent nut and bolt assemblies are changed. A further disadvantage of these known bolting machines is that if nut and bolt assemblies are arranged within oversized bolt holes, they are arranged at slightly different circumferential pitches and at slightly different radial distances from a central axis of the flange, in which case the guide rails and guide wheel will not accurately align the tool head with the next to be manipulated nut and bolt assembly.

European patent application EP 3677537 and US patent 9,364,946 disclose wheel supported bolting tool lifting and supporting devices which are provided with a lever that can be pulled up or down by an operator to lift or lower a bolt manipulation tool relative to each of a series of to be manipulated nut and bolt assemblies that are distributed along the circumference of a bolted flange assembly. Disadvantage of this known lever operated movable bolting tool is that lever takes considerable radial space which prevents traveling around the entire flange circumference when encountering obstacles such as stairs, elevators and mounting brackets. Furthermore, the operator gets fatigued by pulling and pushing the iever continuously when moving to a next to be manipulated nut and bolt assembly.

Website https://www.linkedin.com/posts/ast-industrial_gracias-a-a-su- dise%C3%Blo-ergon%C3%B3mlco-el-carro-ugcPost-6891475201130119168- fO_O/ discloses a movable toolhead lift frame wherein the toolhead is suspended from the frame by four chains, which inhibit lifting of the frame as a result of the descent of the toolhead onto the flange assembly and/or onto the to be manipulated nut and bolt assembly. Disadvantages of this known chain suspension of the toolhead are that it cannot be used on tilted or downward facing flange surfaces and that there is limited control over the toolhead’s motions since it can be uncontrollably tilted or misaligned relative to the to be manipulated nut and bolt assembly during the descent of the toolhead onto the flange assembly and/or onto the to be manipulated nut and bolt assembly.

Czech patent CZ283239 discloses a screw driving device for fitting, tightening and loosening self-tapping screws for fitting a lid of a shell vessel or tank, wherein a screw turning head is connected to a lift frame by a ball joint that provides the turning device with a horizontal degree of freedom of 3 mm in all directions to swing the screw turning head towards a head of the to be tightened or released self-tapping screw. The screw driving device known from CZ283239 is not mounted on a trolley and is not suitable to manipulate nut and bolt assemblies of a bolted flange assembly.

European patent application EP0481284 discloses an apparatus for automatically tightening and untightening bolts of a cylindrical mold for centrifugal casting concrete products, which mold can be opened and closed by a hinging mechanism and nut and bolt assemblies that connect a pair of longitudinally split semi-cylindrical mold sections. The apparatus comprises a tilting device that rotates a nut manipulating head about an pivot axis which is parallel to the central axis of the cylindrical mold so that the manipulating head can be aligned with a to be manipulated nut and bolt assembly to manipulate the assembly and the nut manipulating head can subsequently be pivoted away from the mold.

Disadvantages of the known movable bolting tools are that they are complex and heavy pieces of equipment with fragile and fault prone components, which increase the chance of misalignment of the toolhead relative to a to be manipulated nut and bolt assembly, leading to inhibit any further utilization of the known movable bolting tools and wrongly tightened nut and bolt assemblies which may lead to collapsing of the bolted structure.

Thus, there is a need for a more robust, reliable, compact, light-weight, portable and damage proof improved movable bolting tool for manipulating a bolted flange connection, which tool is self-centering and can, without replacing components, be easily adapted to different flange diameters and pitches between adjacent nut and bolt assemblies and which tool can be easily steered to each of a series of nut and bolt assemblies that are to be manipulated and thereby alleviate disadvantages of the known bolting tools and which improved bolting tool can operate with a minimum of, and optionally without, position, navigation and other fragile wear and damage prone sensors.

Summary of the Invention

In accordance with the invention there is provided a movable bolting tool comprising a toolhead for manipulating nut and bolt assemblies and a trolley for moving the toolhead along a circumference of a bolted flange assembly, which trolley comprises a frame carrying a toolhead supporting assembly to lift or support lifting the toolhead from a manipulated nut and bolt assembly and, after circumferential movement of the movable bolting tool, to engage or support engaging the toolhead with a next to be manipulated nut and bolt assembly; wherein the toolhead supporting assembly is arranged substantially parallel to a substantially vertical lifting direction of the toolhead, the toolhead is pivotably connected to the toolhead supporting assembly with a pivotable connection allowing rotation of the toolhead relative to the toolhead supporting assembly about multiple axes; and a toolhead rotation constraining device is arranged at a distance from the pivotable connection, and configured to constrain the rotation of the toolhead about the multiple axes

Suitable embodiments of the movable bolting tool according to the invention are claimed in the accompanying sub-ciaims 2-14. The pivotable connection preferably allows rotation of the toolhead relative to the toolhead supporting assembly about an x-axis and an y-axis, which x- and y-axes are substantially horizontal, and more preferably about the x-axis, y-axis and a substantially vertical z-axis.

The toolhead rotation constraining device according to one embodiment may be a series of clamps at a small distance, that is typically in the range from 0.1 to 2 cm from the pivotable connection. According to a preferred embodiment, the toolhead rotation constraining device may be at a vertical distance from the pivotable connection. The preferred vertical distance depends on the size of the toolhead, the size of the nut and bolt assemblies to be manipulated, the location of the pivotable connection, etc., but for a toolhead suitable for manipulating nut and bolt assemblies of a bolted flange assembly typically used in wind turbines, typically, the vertical distance will be more than 2 cm, and typically less than 30 cm, for example in ths range of from 3 to 20 cm.

The toolhead rotation constraining device is configured to constrain rotation of the toolhead about multiple axes of the pivotable connection relative to the tooihead supporting assembly. The term ‘constrain’ is used herein to define that on the one hand rotation of the tooihead about multiple axes of the pivotable connection is more limited than would otherwise be possible with the pivotable connection without the presence of the toolhead rotation constraining device, but on the other hand is not so limited to effectively reduce the ability of the toolhead to rotate about multiple axes of the pivotable connection to zero. It is an aspect of the invention that the rotation is constrained but not locked.

The invention further provides a method of manipulating a series of nut and bolt assemblies that are distributed along a circumference of a bolted flange assembly using a movable bolting tool of any one of claims 1-14. According to one embodiment, the bolted flange assembly to be used according to the method of the invention is configured to interconnect flanges of adjacent components of a wind turbine. The movable bolting tool to be used according to the method of the invention may be configured to be moved along the circumference of the bolted flange assembly by an operator or by a robotized control system.

Detailed description of the invention

The toolhead supporting assembly comprised in the movable bolting tool of the invention is configured to lift or support lifting the toolhead from a manipulated nut and bolt assembly and, after circumferential movement of the movable bolting tool, to engage or support engaging the toolhead with a next to be manipulated nut and bolt assembly; wherein the toolhead supporting assembly is arranged substantially parallel to the substantially vertical lifting direction of the toolhead.

The toolhead supporting assembly may according to one embodiment comprise a toolhead lift mechanism and a lift actuator with a motor which is powered by a power source, which motor is configured to activate the toolhead lift mechanism to lift the toolhead from a manipulated nut and bolt assembly and, after circumferential movement of the movable bolting tool, to engage the toolhead with a next to be manipulated nut and bolt assembly wherein a releasable coupling is arranged between the power source and the toolhead, which releasable coupling is configured to let the toolhead engage with the next to be manipulated nut and bolt assembly without actuation of the lift actuator by the motor.

An advantage of the toolhead supporting assembly is that the free engaging motion of the toolhead with the to be manipulated nut and bolt assembly without actuation of the lift actuator creates an impact that promotes a quick axial alignment between the toolhead and the to be manipulated nut and bolt assembly, thus obviating the need for complex positioning and axial alignment tools.

An alternative embodiment is where the toolhead supporting assembly comprises a toolhead lift mechanism and a lift actuator with a motor which is powered by a power source, which motor is configured to activate the toolhead lift mechanism to lift the toolhead from a manipulated nut and bolt assembly and, after circumferential movement of the movable bolting tool, to engage the toolhead with a next to be manipulated nut and bolt assembly, not equipped with a releasable coupling . in this embodiment, the operator typically ensures that the motor is configured and operated such that engagement of the toolhead with the to be manipulated nut and bolt assembiy is still capable of creating an impact that promotes a quick axial alignment between the toolhead and the to be manipulated nut and bolt assembly, thus again obviating the need for complex positioning and axial alignment tools.

According to another embodiment, the toolhead supporting assembly is configured to support lifting the toolhead from a manipulated nut and bolt assembly, but is unable to lift the toolhead in vertical direction sufficiently to allow movement of the movable bolting tool along a circumference of a bolted flange assembly without exerting additional force.

According to yet another embodiment, the toolhead supporting assembiy is configured to support engaging the toolhead with a next to be manipulated nut and bolt assembly, but is unable to engage the toolhead with a next to be manipulated nut and bolt assembly without exerting additional force.

The additional force according to these embodiments, is preferably manual force by an operator of the movable bolting tool.

Where the toolhead supporting assembly is configured to support lifting the toolhead from a manipulated nut and bolt assembly, but is unable to lift the toolhead in vertical direction sufficiently to allow movement of the movable bolting tool along a circumference of a bolted flange assembly without exerting additional force, gravitational force will work alongside the force exerted by the toolhead supporting assembly to engage or support engaging the toolhead with a next to be manipulated nut and bolt assembly. Engagement of the toolhead with the to be manipulated nut and bolt assembly also according to this embodiment is capable of creating an impact that promotes a quick axial alignment between the toolhead and the to be manipulated nut and bolt assembly, thus again obviating the need for complex positioning and axial alignment tools. In one preferred embodiment, gravitational force and the force exerted by the toolhead supporting assembly is sufficient to engage the toolhead with a next to be manipulated nut and bolt assembly, in another preferred embodiment, gravitational force and the force exerted by the toolhead supporting assembly is sufficient to support engaging the toolhead with a next to be manipulated nut and bolt assembly but an additional force, suitably manual force, is additionally required to ensure the toolhead engages with a next to be manipulated nut and bolt assembly, for example to overcome a drag resistance force.

Where the toolhead supporting assembly is configured to support engaging the toolhead with a next to be manipulated nut and bolt assembly, but is unabie to engage the toolhead with a next to be manipulated nut and bolt assembly without exerting additional force, such additional force may typically be provided manually.

According to a preferred embodiment, the toolhead supporting assembly comprises a lift actuator or spring contractible and extendible in a substantially vertical lifting direction directly or indirectly connected to a lift arm, wherein the toolhead is pivotably connected to the lift arm with a pivotable connection allowing rotation of the toolhead relative to the lift arm about multiple axes; and a toolhead rotation constraining device arranged at a distance, preferably vertical distance, from the pivotable connection, and configured to constrain rotation of the toolhead relative to the lift arm about multiple axes.

Preferably, the frame comprises a lift tower, more preferably one lift tower, which extends substantially parallel to the lifting direction of the toolhead and wherein the lift arm of the toolhead supporting assembly is substantially vertically slidably connected to the lift tower. The slidable connection may suitably include guidewheels or guiderails. Where the frame comprises one lift tower, preferably one toolhead supporting assembly, in particular one lift arm of a toolhead supporting assembly is used.

According to one embodiment, use is made of drag resistance to ensure the toolhead remains balanced in the same vertical position if no additional force, such as manuai force, is exerted. Thus, according to one preferred embodiment of the movable bolting tool, the toolhead supporting assembly further comprises a pulley connected to the lift tower, and a flexible connection, such as a chain, cord or cable, connecting the lift actuator or spring via the pulley with the lift arm substantially vertically slidably connected to the lift tower.

Typically the pivotable connection is configured to allow rotation of the toolhead about at least the x and y axis to align the toolhead’s central axis with the central axis of the next to be manipulated nut and bolt assembly. If the pivotable connection is not able to allow rotation of the toolhead about the z-axi$, then it may be more difficult to accommodate nut and bolt assemblies that are irregularly placed in a bolted flange assembly due to oversized bolt holes. In one embodiment, the pivotable connection comprises a pin in an oversized joint hole. According to another embodiment, the pivotable connection comprises an universal joint.

According to a preferred embodiment, the pivotable connection allows rotation of the toolhead relative to the toolhead supporting assembly about three axes (that is the x, y and z axis). This can be achieved by for example a combination of a vertical hinge and an universal joint.

Optionally, the pivotable connection is one pivotable connection and not a plurality of pivotable connections. In such case the pivotable connection may comprise a single ball joint.

The toolhead rotation constraining device according to one embodiment comprises a pin slotted in an oversized joint constraint. Preferably, the pin is connected to the toolhead and the oversized joint constraint connected to the toolhead supporting assembly, in particular the lift arm.

It will be appreciated that the space inside the oversized joint constraint, the distance, in particular the vertical distance, from the pivotable connection, the diameter of the pin relative to the space inside the oversized joint constraint all contribute to the amount of play of the pin in the slot and thereby the amount of rotation available for the toolhead. The play should be sufficient to enable (axial) alignment of the toolhead with irregularly positioned to be manipulated nut and bolt assemblies. On the other hand, the play should not be such as to allow undesired rotation, swinging etc., of the toolhead when the movable bolting tool is moved along a circumference of a bolted flange assembly.

It belongs to the skill of the skilled person to select the appropriate size, dimensions and distance, in particular vertical distance relative to the pivotable connection, for the pin and oversized joint constraint. It further belongs to the skill of the skilled person to vary the appropriate size, dimensions and/or distance, in particular vertical distance relative to the pivotable connection, for the pin and oversized joint constraint in case a different toolhead and/or a different size nut and bolt assemblies and/or a more or less irregularly positioned nut and bolt assemblies in a bolted flange assembly are to be manipulated. Preferably, the toolhead rotation constraining device is configured such that the appropriate size, dimensions and/or distance, in particular vertical distance relative to the pivotable connection, for the pin and/or oversized joint constraint can be easily varied, for exampie by adjustment means.

Brief Description of the Drawings

The invention will be explained in more detail below by a number of execution examples and accompanying drawings.

In the drawings:

Figure 1 shows a first embodiment of the movable bolting tool comprising a toolhead supporting assembly (1,67₍9a,9b), arranged parallel to the substantially vertical lifting direction of the toolhead, the toolhead is pivotably connected to the toolhead supporting assembly with a pivotable connection (80) allowing rotation of the toolhead relative to the toolhead supporting assembly about three axes; and a toolhead rotation constraining device (95) arranged at a vertical distance (BB) from the pivotable connection.

Figures 2 and 3 show the toolhead and a bolted flange assembly viewed in the direction of the y~axis.

Figure 4 shows the movable bolting tool with pivotable connection at a horizontal distance from the central axis through the toolhead.

Figure 5 shows the same moveable bolting tool of figure 4, but with the toolhead aligned and engaging with the to be manipulated nut and bolt assembly.

Figure 6 shows an alternative embodiment of the movable bolting tool in which the pivotable connection is positioned at the top of the toolhead, substantially at the central axis of the toolhead.

Figure 7 shows the toolhead and the toolhead rotation constraining device (in the form of a pin slotted in an oversized joint constraint) in horizontal cross-section while the toolhead is rotating about the X-axis.

Figure 8 shows the toolhead and the toolhead rotation constraining device (in the form of a pin slotted in an oversized joint constraint) in horizontal cross-section, while the toolhead is rotating about the Y-axis.

Figure 9 shows a toolhead of a movable bolting tool made and operated in accordance with the invention.

Detained Description of the Depicted Embodiments

Figure 1 shows an exemplary embodiment of the movable bolting tool for manipulating nut and bolt assemblies according to the invention. The movable bolting tool comprises a trolley with a L-shaped lift frame 4 and wheels 2a, 2b that are connected to the bottom section of the L-shaped lift frame 4, which wheels 2a, 2b rest on a bolted flange assembly 10. The bottom section of the L-shaped lift frame 4 is configured such that it can be positioned aside and below the bolted flange assembly 10 to provide space for the toolhead. Toolhead 3 is pivotably connected to lift arm 67 by bail joint 80. At a distance BB from the ball joint, toolhead rotation constraining device 95 is provided in the form of a pin 85 slotted in an oversized joint constraint 90. Spring 86 connects lift arm 67 and toolhead 3. In one embodiment spring 86 is configured to reduce pressure on pin 85 and oversized joint constraint 90 when pin 85 is pressed against a side of oversized joint constraint 90. However, in the embodiment of Figure 1 , spring 86 is configured such that toolhead 3 remains in a substantially vertical position and does not substantially rotate about the x-axis (arrow 27) and/or about the y-axis (arrow 28), despite ball joint 80 being connected to toolhead 3 at a distance from the toolhead’s central vertical axis E. Gas spring 1 is connected with frame 4 and with lift arm 67. Lift arm 67 is provided with wheels 9a, 9b which guide lift arm 67 over a vertical lift tower 4b of the L-shaped frame 4.

The movable bolting tool is driven along the bolted flange assembly 10 by wheels 2a and 2b to bring toolhead 3 substantially above the to be manipulated nut and bolt assembly 12d, 11d, which forms part of a series of nut and bolt assemblies, of which assemblies 12a-f and 11a-f are shown, that are distributed at regular pitches along the circumference of the bolted flange assembly 10. The nut and bolt assemblies present in bolted flange assembly 10 are manipulated by toolhead 3 to tighten, release, or check the required tension in the bolt. Toolhead 3 may comprise torque wrench (not shown) formed by a socket wrench with a hexagonal inner surface to tighten or release nut 12d and optionally also comprise a bolt tensioning device as depicted in the figure that is screwed around an upper end of, and tightens bolt 11d by pulling with the bolt tensioning device such that bolt 11d is tensioned before the nut 12d is rotated by the torque wrench (not shown), such as a hydraulic bolt tensioning device known from European patent EP 3894138 of Tentec Ltd.

In the embodiment shown in Figure 1 , as a result of the bolt tensioning by the bolt tensioning device, the lower end of toolhead 3 is pressed against the upper surface of the bolted flange connection 10, which inhibits other parts of toolhead 3 to rotate relative to the bolted flange connection 10 when the torque wrench (not shown) is rotated within toolhead 3 to tighten or reiease the to be manipulated nut 12d. After unscrewing the bolt tensioning device and lifting toolhead 3 from the manipulated nut and bolt assembly 12d, 11d the movable bolting tool is moved to a next to be manipulated nut and bolt assembly 12e, 11e by rolling wheels 2a, 2b over the bolted flange assembly 10.

In the embodiment of Figure 1, toolhead supporting assembly 1 , 67, 9a, 9b, comprises a gas spring 1 which is configured to maintain lift arm 67 and toolhead 3 pivotably connected to lift arm 67 in a position where the movable bolting tool can be moved along the bolted flange assembly 10 without engaging nut and bolt assemblies 11 a-f, 12a~f. The force required for the toolhead to engage a next to be manipulated nut and bolt assembly may be manual force by an operator of the movable bolting tool, or may be provided by an actuator (not shown) driven by a motor (not shown) pulling lift arm 67 down against the gas spring 1 , and thereby toolhead 3 towards nut and bolt assemblies 1 la-f, 12a-f. In the embodiment of Figure 1 , gas spring 1 pushes toolhead 3 in upward direction and effectively reduces the weight with which toolhead 3 is engaging with a to be manipulated nut and bolt assembly 11 a-f, 12a-f, when toolhead 3 is forced down by manual force or an actuator driven by a motor. Spring 86, dimensioned and configured according to this embodiment, keeps toolhead 3 in a vertical position by balancing the weight of toolhead 3. This allows toolhead 3 to be axially aligned with a to be manipulated nut and bolt assembly. This axial alignment prevents having to fully rely on the weight of toolhead 3 creating an impact promoting a quick axial alignment between the toolhead and the to be manipulated nut and bolt assembly, in this embodiment, the force, in particular the manual force, with which toolhead 3 is moved down towards the nut and bolt assembly is not particularly critical. As spring 86 keeps toolhead 3 balanced, limited additional force, if any, is required to align toolhead 3 with a to be manipulated nut and bolt assembly. Therefore, also in this embodiment, the need for complex positioning and axial alignment tools is avoided.

Figures 2 and 3 depict a toolhead 3 pivotably connected to a ball joint 80 and a bolted flange assembly 10 with a to be manipulated nut and bolt assembly 11f, 12f. The toolhead and bolted flange assembly in Figures 2 and 3 are shown in the plane provided by the x- axis and the z-axis, unlike Figure 1 , which was shown in the plane provided by the y~axis and z~axis. For simplicity, frame 4 , wheel 2a, 2b and any part of lift arm 67 or spring or actuator 1 that may be visible when viewed in the plane provided by the x-axis and z-axis, have been omited from Figures 2 and 3. Arrow 27 depicts rotation about the x-axis, represented by dashed line B. Arrow 28 depicts rotation about the y-axis (represented by dashed line C in Figure 1). Dashed line E is the axial line through toolhead 3 and as ball joint 80 is located at a horizontal distance from axial line E, it will be appreciated that rotation about the z-axis is not represented by dashed line E. Rotation about the z-axis of the ball joint 80 allows toolhead 3 to move about laterally, substantially along the x- axis, as depicted by distance XX. This allows the movable bolting tool to accommodate random variation of the positions of nut and bolt assemblies 11a-f, 12a-f. Boit holes in flange assembly 10, to receive the nut and bolt assemblies

11a-f, 12a-f as shown in Figure 1 , are typically oversized relative to the outer circumference of the screw threads of the bolts 11 a-11f to facilitate smooth insertion of the bolts 11 a-11f into these bolt holes. This may cause this random variation relative to a pitch circle at which bolt holes are drilled through the flange assembly 10. Figure 3 shows an embodiment where spring 86 in Figure 1 is either not present or not dimensioned such that the toolhead remains substantially vertical along axial line E. Ball joint 80 at a horizontal distance from central axis E causes toolhead 3 to rotate under the influence of gravitational force, about the y- axis, represented by angle 8 in Figure 3, and about the x-axis, represented by angle a in Figure 4.

Figure 4 shows an embodiment where spring 86 is not present and toolhead supporting assembly 1 , 9a, 9b, 67 comprises a lift actuator 1 powered by a power source (not shown) and lift arm 67 guided by wheels 9a,9b. In another embodiment lift actuator 1 may be replaced by a combination of a lift actuator 1 and a spring, preferably a gas spring. Where a lift actuator and a (gas) spring are to be used in combination, preferably, the (gas) spring does not provide more than 80% of the upward force needed to keep toolhead 3 in a lifted position, to allow the movable bolting tool to move along bolted flange assembly 10 without the toolhead 3 bumping into or otherwise engaging nut and bolt assemblies 11 a~f, 12a-f. Typically, where a lift actuator and a (gas) spring are to be used in combination, the (gas) spring will provide at least 10% of the upward force required. According to a preferred embodiment the (gas) spring and the lift actuator to be used in combination are dimensioned such that the (gas) spring provides in the range of from 30 to 70% of the upward force required. In the embodiment of Figure 4, rotation about ball joint 80 is restricted by pin 85 pressing against a side of the oversized joint constraint 90 of toolhead rotation constraining device 95. As shown in Figure 7, oversized joint constraint is suitably provided with v-shaped recess 91 to receive the pin 85, represented by dashed line 85a. This recess 91 further restricts movement of toolhead 3, in position represented by dashed line 3a when pin 85 is in position 85a, when the movable bolting tool is moved along bolted flange assembly 10. As shown in Figure 7, oversized joint constraint 90 may in one embodiment be provided with a spring 92, for example to assist in dampening of swinging motions when toolhead 3 is moved along bolted flange assembly 10 and to keep pin 85 substantially in position 85a, and accordingly toolhead 3 substantially in position 3a.

Figure 5 shows the movable bolting tool as shown in Figure 4, but with lift actuator 1 in a more contracted position and toolhead 3 engaging with bolt 11d of nut and bolt assembly 11d, 12d. The toolhead 3 comprises a bolt tensioning device that is screwed around an upper end of, and tightens bolt 11d by pulling with the bolt tensioning device such that bolt 11d is tensioned before the nut 12d is rotated by a torque wrench (not shown) incorporated in toolhead 3. Toolhead 3 has been aligned axially with the to be manipulated nut and bolt assembly 11 d, 12d by the impact of the toolhead 3 on bolt 11d created by the contraction of lift actuator 1. As a result of the alignment of toolhead 3, pin 85 is no longer positioned in v- shaped recess (91 in Figure 7) of the oversized joint constraint 90 of toolhead rotation constraining device 95.

Figure 6 shows another embodiment of the present invention in which the toolhead supporting device 1, 67, 9a, 9b comprises a lift actuator 1 powered by a power source (not shown) and a gas spring (not shown). The gas spring provides about 50% of the upward force needed to keep toolhead 3 in a lifted position. As compared with the embodiments shown in figures 1 , 4 and 5, lift arm 67 is extended to a position above toolhead 3. Ball joint 80 connects lift arm 67 with toolhead 3 substantially at the axial line E through toolhead 3. Toolhead rotation constraining device 95 in the form of pin 85 slotted in oversized joint constraint 90 connects lift arm 67 and toolhead 3 at a distance from ball joint 80. If the weight distribution in toolhead 3 is substantially homogenous, as in the toolhead 3 shown in Figure 6, pin 85 does not abut against one side of oversized joint constraint 90 when toolhead 3 is in the lifted position. Bolt play as shown in Figure 2 by distance XX may be more difficult to accommodate. Therefore, ball joint 80 is preferably slidably connected in the X-direction to toolhead 3 to allow toolhead 3 to travel distance XX in the X-direction. Figure 8 shows the toolhead 3 and the toolhead rotation constraining device, in the form of a pin 85 slotted in an oversized joint constraint 90 in horizontal crosssection, while the toolhead 3 is rotating about the y-axis. Rotation about the y-axis may for example move toolhead 3 to position 3b. This rotation causes pin 85 to move to position 85b, where pin 85 in position 85b abuts oversized joint constraint 90 and further rotation is restricted. Figures 7 and 8 show how the pin 85 slotted in oversized joint constraint 90 is effective in constraining rotation of toolhead 3 about the x-axis and the y-axis. If desired, the toolhead rotation constraining device of figures 7 and 8 can also be provided with means to constrain rotation about the z-axis. For example, by an L~shaped pin 85 positioned between two protruding struds (not shown) extending vertically from oversized joint constraint 90 and rotation about the z-axis of L-shaped pin 85 constrained by the protruding studs. Especially in the embodiment shown in Figure 6, where the ball joint is not positioned directly vertical above the toolhead rotation constraining device, but at an angle relative to the vertical, rotation about the z-axis of ball joint 80 will result in a movement of pin 85 in the horizontal x-y plane. Pin 85 will therefore abut oversized joint constraint 90 effectively constraining rotation about the z-axis of ball joint 80.

Figure 9 shows an embodiment of the movable bolting tool in which a frame 4 is provided with a toolhead supporting assembly comprising lift actuator 1. A toolhead 3 is connected by means of ball joint 80 to a lift arm (not shown) encompassed in the vertical lift tower 4b of frame 4. At a vertical distance from ball joint 80, pin 85 slots into an oversized joint constraint (not shown). Similarly to the embodiment shown in Figure 1, a spring 86 is provided. In the embodiment shown in Figure 9, spring 86 is positioned between frame 4 and toolhead 3. The lift tower 4b of frame 4 is further provided with wheel 87. In operation, wheel 87 may rest against a pipe (not shown) to prevent tilting of the movable bolting tool. The pipe is provided with a flange that is part of the bolted flange assembly with nut and bolt assemblies to be manipulated by the movable bolting tool. Frame 4 is further provided with wheels 2a, 2b and wheels 2d, 2e. In operation, wheels 2a, 2b rest on bolted flange assembly 10, as shown in Figure 1, and wheels 2d, 2e prevent the movable bolting tool from rotating forward and falling off the bolted flange assembly. Bolt guides 31a, 31b guide the movable bolting tool along the path of the to be manipulated nut and bolt assemblies. A prototype of the movable bolting tool shown in Figure 9 was made and successfully tested. Although in the embodiments shown in Figures 1-9, the toolhead rotation constraining device 95 is in the form of a pin 85 slotted in an oversized joint constraint, it is to be understood that other toolhead rotation constraining devices may be used in accordance with the invention. For exampie, according to one embodiment, the toolhead rotation constraining device is configured to releasably constrain rotation of the toolhead about multiple axes, in particular the x and y axes, relative to the trolley during circumferential movement of the movable bolting tool. The toolhead rotation constraining device in this embodiment operates to restrict rotation of the toolhead relative to the trolley during circumferential movement of the movable bolting tool. The pin slotted in an oversized joint constraint depicted in Figures 7 and 8 is one such embodiment but many variants are possible. Preferably, the oversized joint constraint is at least on one side an ellipsoid or oval-shaped oversized joint constraint, or contains on at least one side a V or U-shaped recess, where the at least one side is arranged to receive the pin during circumferential movement of the movable bolting tool.

In one embodiment, as depicted in Figures 4-6, the pin 85 is connected to the toolhead 3 and the oversized joint constraint 90 to the lift arm 67, but it is equally possible to connect the oversized joint constraint 90 to the toolhead 3 and the pin 85 to the lift arm 67.

In another embodiment, the toolhead rotation constraining device is an electromagnet, which electromagnet is in operation during circumferential movement of the moveable bolting tool.

The toolhead rotation constraining device according to one embodiment may be a plurality of constraining devices where each constraining device is configured to constrain rotation about one axis of the pivotable connection. According to another preferred embodiment, one constraining device is configured to constrain rotation about two axes, such as the x-axis and the y-axis, and another constraining device is configured to constrain rotation about the remaining axis, such as the z-axis, rotation of which is not constrained by the one constraining device configured to constrain rotation about two axes. According to yet another preferred embodiment, one constraining device is configured to constrain rotation about three axes.

Although the invention has been explained in more detail on the basis of only a few execution examples, it is clear that the invention is in no way limited to these examples. On the contrary, many variations and appearances are still possible for an average craftsman within the framework of the invention. For example, the implementation examples are based on a linear step mechanism, but a curved step mechanism can also be used for this purpose that follows the contour of the flange connection. Also, bolt pre-tension measuring, inspection, manipulation and other tools other than those mentioned can similarly be self-centered with the nut and bolt assembly, including intended bolted connections and cavities. Furthermore, it is observed that features and embodiments shown in the accompanying drawings and/or described in this specification, abstract and claims may be combined in several ways.

Claims

Claims A movable baiting tool comprising a toolhead for manipulating nut and bolt assemblies and a trolley for moving the toolhead along a circumference of a bolted flange assembly, which trolley comprises a frame carrying a toolhead supporting assembly to lift or support lifting the toolhead from a manipulated nut and bolt assembly and, after circumferential movement of the movable bolting tool, to engage or support engaging the toolhead with a next to be manipulated nut and bolt assembly; wherein the toolhead supporting assembly is arranged substantially parallel to a substantially vertical lifting direction of the toolhead, the toolhead is pivotably connected to the toolhead supporting assembly with a pivotable connection allowing rotation of the toolhead relative to the toolhead supporting assembly about multiple axes; and a toolhead rotation constraining device is arranged at a distance from the pivotable connection, and configured to constrain the rotation of the toolhead about the multiple axes. The movable bolting tool of claim 1 , wherein the toolhead supporting assembly is configured to support lifting the toolhead from a manipulated nut and bolt assembly, but is unable to lift the toolhead in vertical direction sufficiently without exerting additional manual force by an operator of the movable bolting tool, The movable bolting tool of claim 1 or 2, wherein the toolhead supporting assembly comprises a lift actuator or spring, which is, when in use, contractible and extendible in a substantially vertical lifting direction and which is directly or indirectly connected to a lift arm, wherein the toolhead is pivotably connected to the lift arm with a pivotable connection allowing rotation of the toolhead relative to the lift arm about multiple axes; and the toolhead rotation constraining device is arranged at a distance from the pivotable connection, and configured to constrain the rotation of the toolhead relative to the lift arm about the multiple axes. The movable bolting tool of claim 3, wherein the frame comprises a lift tower, which extends substantially parallel to the lifting direction of the toolhead and wherein the lift arm of the toolhead supporting assembly is substantially vertically slidably connected to the lift tower. The movable bolting tool of claim 4, wherein the frame comprises a single lift tower. The movable bolting tool of any one of the preceding claims, wherein the bolted flange assembly has a substantially cylindrical circumference and a substantially vertical central axis, and the toolhead contains an internal rotating device to engage with and manipulate the nut and bolt assembly by rotating the internal rotating device relative to the toolhead about a substantially vertical axis of rotation, and the toolhead is configured to extend, when in use, substantially vertically and substantially parallel to the central axis of the flange assembly and the pivotable connection is connected to the toolhead at a substantially horizontal distance from the substantially vertical axis of rotation of the internal rotating device. The movable bolting tool of any one of the preceding claims, wherein the pivotable connection comprises a pair of substantially orthogonal tubular pivots that allow the toolhead to pivot relative to the toolhead supporting assembly about two mutually orthogonal pivot axes. The movable bolting tool of any one of claims claim 1-6, wherein the pivotable connection comprises a ball joint that allows the toolhead to pivot relative to the toolhead supporting assembly about three substantially orthogonal pivot axes. The movable bolting tool of any one of the preceding claims, wherein the toolhead rotation constraining device comprises a pin slotted in an oversized joint constraint. The movable bolting tool of claim 9, wherein the pin is connected to the toolhead and the oversized joint constraint connected to the toolhead supporting assembly, in particular the lift arm. The movable bolting tool of claim 9 or 10, wherein the pivotable connection is connected to the toolhead at a distance below the top of the toolhead and one element of the pin slotted in the oversized joint constraint assembly is connected to the toolhead at a vertical distance from the pivotable connection and at a distance below the top of the toolhead. The movable bolting tool of claim 11 , wherein the oversized joint constraint contains an u-shaped or v-shaped recess equipped to receive the pin when the toolhead is lifted from the to be manipulated nut and bolt assembly for moving along a circumference of a bolted flange assembly. The movable bolting tool of claim 12, wherein a spring connecting the toolhead and the toolhead supporting assembly or frame is configured to reduce pressure on the pin and oversized joint constraint when the pin is slotted in the u-shaped or v-shaped recess. The movable bolting tool of claim 6, wherein the trolley comprises vertical guide wheels that are configured to engage a disk-shaped upper surface of the bolted flange assembly and lateral guide wheels that are configured to engage the cylindrical outer circumference of the bolted flange assembly, and wherein the trolley further comprises lateral guide elements, such as bolt guide plates, that are configured to slide along the nut and bolt assemblies at an inner circumference thereof, such that the lateral guide wheels and the lateral guide elements are arranged at opposite sides of the series of the circumferentially spaced nut and bolt assemblies to guide the trolley in a substantially circumferential direction along the bolted flange assembly and to inhibit rotation of the trolley relative to the bolted flange assembly when the torque wrench is rotated relative to the toolhead for tightening or releasing a to be manipulated nut and bolt assembly. A method of manipulating a series of nut and bolt assemblies that are distributed along a circumference of a bolted flange assembly, wherein use is made of the movable bolting tool of any one of claims 1-14.