A large hydraulic cylinder installation device and installation method in a confined space

Abstract

A large hydraulic cylinder installation device and installation method in a confined space, the installation device comprising a lifting ring, an adjustable support frame for installing the lifting ring, and a bridge type support for matching the cylinder and pressing the hinge shaft into two installation holes of the rotating frame; the adjustable support frame 1 comprises a support frame body, and a lifting ring is arranged on each of the front and rear sides of the support frame body; the bridge type support comprises a bridge type support frame body, a positioning seat for positioning the hinge shaft is arranged at the end of one arm, and a manual jack for pressing the bearing sleeve assembly is arranged at the end of the other arm. The installation device solves the problems of uncontrolled quality, low installation efficiency, and quality hidden dangers in long-term use caused by the assembly method of the large hinge shaft installation structure hydraulic cylinder in the confined space, no effective stress point, and artificial knocking. The cylinder installed by the method of the application reduces the phenomena of seepage and oil leakage in the use process, reduces the labor intensity during installation, improves the assembly efficiency, and reduces the safety hidden danger in the assembly process.

Description

Technical Field

[0001] This invention relates to hydraulic cylinders, and more particularly to a mounting device and method for installing large hydraulic cylinders. Background Technology

[0002] Hydraulic cylinders, as actuators in hydraulic systems, achieve reciprocating motion through the extension and retraction of piston rods. Hydraulic cylinders can be designed with different structures based on their motion mode, force application, and structural form, taking into account their application and installation environment. However, in practical use, the main installation methods for hydraulic cylinders include tie rod structures, clevis structures, foot structures, hinge shaft structures, and flange structures. The installation methods for hydraulic cylinders with different installation structures also differ depending on the actual installation environment.

[0003] The large landing platform measures 3.2m x 2.4m and has a load capacity of 8-10 tons. The rotating frame allows the platform to rotate in different orientations to meet specific requirements. The rotating frame is mounted on a structure approximately 1.7 meters above the ground. Two large hydraulic cylinders (referred to as cylinders 8) are installed inside the rotating frame. The cylinder barrels are mounted on the rotating frame 7 via hinges. Piston rod shackles 81 are mounted on the large landing platform 9. The lifting and lowering function of the large landing platform 9 is achieved through the extension and retraction of the piston rods (e.g.,...). Figure 7-11 To reduce the space occupied by the rotating frame, the overall structure is relatively compact. The hydraulic cylinder is installed in a confined space (i.e., the inner cavity) of about 1260mm x 252mm between two welded beams inside the rotating frame.

[0004] The large hydraulic cylinder measures 1580mm x 250mm and weighs approximately 360kg. With the piston rod fully extended, the cylinder's total length reaches 2600mm. Assigning the hinge shaft and bearing sleeve assembly of this large hydraulic cylinder to the mounting holes on the rotating beam has always been a challenge.

[0005] The current installation method is as follows: the hydraulic cylinder is lifted to the installation position by a gantry crane. The operator visually aligns the hinge shaft 82 and the mounting hole 71 by raising and lowering the gantry crane. Due to the large error of the gantry crane, repeated raising and lowering are required to achieve effective alignment. Then, the assembly is carried out by a relatively primitive hammering method. Specifically: First, install the bearing sleeve assembly on the outer beam of the rotating frame. The bearing is installed at the inner end of the bearing sleeve 65 via a retaining ring. The outer circle of the bearing sleeve 65 and the mounting hole on the rotating frame beam are interference fit. After the outer end of the inner cavity of the bearing sleeve 65 is clamped with a tooling plate, the tooling plate is struck with a sledgehammer to install the bearing sleeve 65 into the mounting hole. Then, use a gantry crane to lift the hydraulic cylinder to the installation position between the two beams on the rotating frame. The bearing sleeve assembly on the inner beam of the rotating frame is installed using the above method. One person strikes the tooling plate to gradually insert the bearing sleeve assembly into the mounting hole on the beam. When the bearing in the bearing sleeve assembly is about to contact the hydraulic cylinder hinge shaft, one person is responsible for observing the alignment of the hinge shafts at both ends of the hydraulic cylinder with the bearing holes in the bearing sleeve assembly on the inner and outer beams of the rotating frame and directing the lifting and lowering of the gantry crane to ensure that the hinge shafts at both ends of the hydraulic cylinder can be installed into the bearing holes in the bearing sleeve. Then, the tooling plate is struck to completely install the bearing sleeve assembly into the mounting hole, thereby pushing the hinge shafts at both ends of the hydraulic cylinder into the bearing holes.

[0006] This method has the following problems: 1. The assembly process requires a high level of operator skill and responsibility, and is greatly affected by the operator's subjective factors, resulting in uncontrolled installation quality. 2. Oil cylinders may leak or bleed during use, requiring maintenance or replacement. 3. Due to the compact structure of the rotating frame, the outer beam is suspended without an operator's standing position, requiring the operator to use a ladder for installation, posing a safety hazard and requiring dedicated space for the ladder. 4. Due to the limited internal space of the rotating frame, there is insufficient space for the operator to use a sledgehammer, increasing the difficulty of striking the tooling plate. Summary of the Invention

[0007] The purpose of this invention is to overcome the above-mentioned shortcomings of the prior art and to provide a large hydraulic cylinder installation device and method for confined spaces. By ensuring the parallelism of the cylinder hinge shaft and the piston rod lug, the invention reduces the occurrence of oil leakage during the use of the cylinder, reduces the labor intensity during installation, improves assembly efficiency, and reduces safety hazards during assembly operations.

[0008] The technical solution of this invention is: a method for installing a large hydraulic cylinder in a confined space, comprising the following steps:

[0009] A) First, hoist the hydraulic cylinder to be installed using an adjustable support frame. When the hydraulic cylinder is hoisted by the adjustable support frame, it is in an inclined state. Then, hoist the entire adjustable support frame to the installation position on the rotating frame beam. After initially adjusting the hydraulic cylinder hinge shaft to be aligned with the installation hole, lock the adjustable support frame with a locking screw. The rotating frame beam forms the inner cavity of the rotating frame, and the hydraulic cylinder is placed in the inner cavity of the rotating frame.

[0010] The positioning seat and a bearing sleeve assembly to be installed are pre-installed in the mounting holes on the rotating beam;

[0011] The bridge support is hoisted onto the rotating beam. One arm of the bridge support is engaged with the positioning seat, and the jack at the other arm of the bridge support corresponds to the bearing sleeve assembly. There is a gap between the jack and the bearing sleeve assembly. The hand-operated jack preloads the bearing sleeve assembly. One arm of the bridge support is engaged with the cylindrical part at the outer end of the positioning seat, and the jack at the other arm of the bridge support is pressed onto the pressure plate at the outer port of the bearing sleeve assembly. Both arms of the bridge support are under load, and the bridge support is erected on the rotating beam. The purpose of preloading the bearing sleeve assembly is: 1. To ensure that the bridge support can stand upright after being loaded at both ends; 2. To initially determine whether the outer circle of the bearing sleeve assembly is aligned with the mounting hole.

[0012] Adjust the height adjustment screw on the adjustable support frame 1, so that one side of the hydraulic cylinder hinge shaft is completely lowered into the semi-circular sleeve of the positioning seat. After the other side hinge shaft is aligned with the center of the bearing hole, press the jack by hand to press the bearing sleeve assembly into place.

[0013] B) Remove the bridge support and positioning seat from below the adjustable support frame. Pre-install another bearing sleeve assembly to be installed at the mounting hole of the positioning seat in step A. Rotate the bridge support 180°. The end of one arm of the bridge support is engaged with the bearing sleeve assembly installed in step A. The jack at the end of the other arm of the bridge support corresponds to the bearing sleeve assembly to be installed. There is a gap between the jack and the bearing sleeve assembly to be installed. Use the hand jack to pre-press the bearing sleeve assembly to be installed. The two arms of the bridge support are under force. The bridge support is erected on the rotating beam. Use the hand jack to press the bearing sleeve assembly to be installed into place.

[0014] C) After pre-aligning the cylinder piston rod clevis with the installation position of the large lifting platform, use a tensioning and centering shaft to pre-install the cylinder piston rod clevis with the installation position. The installation direction of the tensioning and centering shaft is opposite to that of the shaft required by the product. Insert the cold-installed shaft into the installation position of the large lifting platform from the chamfered end of the tensioning and centering shaft, and push out the tensioning and centering shaft to complete the cylinder assembly.

[0015] The adjustable support frame includes a support frame body, which comprises two frames connected as a whole by a lifting beam. Each of the two frames has a mounting base at its upper end, and a height adjustment screw is mounted on the outer side of the mounting base. The end of the height adjustment screw is connected to a rotating lifting ring for lifting the cylinder barrel to be installed in a confined space. The front and rear lifting straps are connected to the rotating lifting ring. Two upright plates are welded to one side of each frame's support leg, and locking screws are mounted on the outer upright plates.

[0016] The bridge support includes a bridge support frame, with a positioning seat for positioning the hinge shaft at one end of one arm and a jack for pressing the bearing sleeve assembly at the other end of the other arm. The positioning seat includes a cylindrical part at the outer end and a semi-circular sleeve part connected to the inner end of the cylindrical part, the inner cavity of the semi-circular sleeve part forming a positioning cavity for positioning the hinge shaft. A radially arranged partition is provided between the cylindrical part and the semi-circular sleeve part, and a small screw for disassembling the positioning seat is installed on the partition. A positioning step is provided at the end of the support arm, and the cylindrical part of the positioning seat is engaged with the positioning step.

[0017] The bearing sleeve assembly includes a bearing sleeve and a bearing whose inner cavity is centered by a bearing positioning sleeve. The bearing is installed at the inner port of the bearing sleeve via a retaining ring, and a pressure plate is clamped at the outer port of the bearing sleeve; the pressure plate cooperates with a jack.

[0018] Two hydraulic cylinders are installed inside the rotating frame, which is mounted on a frame 1.7 meters above the ground. The large lifting platform measures 3.2m x 2.4m. The cylinder barrels are mounted on the rotating frame via hinges, and piston rod shackles are installed on the mounting points of the large lifting platform. The lifting and lowering function of the large lifting platform is achieved by extending and retracting the piston rod. The hydraulic cylinder weighs 360kg and has a total length of 2600mm when the piston rod is fully extended.

[0019] In step B, the bridge support is erected on the rotating beam. Observe whether the inner wall of the bearing bore is aligned with the outer circle of the hinge shaft. If they are not aligned, fine-tune the height adjustment screw until the inner ring of the bearing is aligned with the hinge shaft. After alignment, use a hand jack to press the bearing sleeve assembly to be installed into place.

[0020] A large hydraulic cylinder mounting device for confined space includes an adjustable support frame and a bridge support for mating with the cylinder, which is press-fitted into two mounting holes of a rotating frame 7.

[0021] The adjustable support frame includes a support frame body, which includes two frames connected as a whole by a hoisting beam. The upper ends of the two frames are respectively equipped with mounting seats, and the outer side of the mounting seats is equipped with height adjustment screws. The ends of the height adjustment screws are connected to a rotating lifting ring for lifting the cylinder barrel of the hydraulic cylinder to be installed in a confined space. The front and rear lifting straps are connected to the rotating lifting ring.

[0022] The bridge support includes a bridge support frame, with a positioning seat for positioning the hinge shaft at one end of one arm and a jack for pressing the bearing sleeve assembly at the other end of the other arm.

[0023] Two upright plates are welded to one side of the two support legs of the adjustable support frame, and locking screws are installed on the outer upright plates; the cylinder barrel is tilted when lifted by the front and rear slings; the front and rear slings are connected to the rotating lifting rings by hooks.

[0024] The mounting base has a bayonet on its inner side, and the lifting beam that is locked in the two bayonet points is welded to the two frames to form a whole; the end of the height adjustment screw is connected to the sling via a rotating ring, and the sling is hooked to the rotating ring via a hook.

[0025] The positioning seat includes a cylindrical part located at the outer end and a semi-circular sleeve part connected to the inner end of the cylindrical part. The inner cavity of the semi-circular sleeve part forms a positioning cavity for the positioning hinge shaft. There is a radially arranged partition between the cylindrical part and the semi-circular sleeve part, and a small screw for disassembling the positioning seat is installed on the partition.

[0026] The end of the support arm is provided with a positioning step, and the cylindrical part of the positioning seat is engaged with the positioning step.

[0027] The bearing sleeve assembly includes a bearing sleeve and a bearing whose inner cavity is centered by a bearing positioning sleeve. The bearing is installed at the inner port of the bearing sleeve via a retaining ring, and a pressure plate is clamped at the outer port of the bearing sleeve. The pressure plate cooperates with a jack. The bearing positioning sleeve is detachably installed inside the bearing sleeve. The bearing positioning sleeve has a radial partition in the middle, and a small screw for disassembling the bearing positioning sleeve is installed on the radial partition.

[0028] The inventors discovered through research that the existing installation methods cause the above problems as follows: 1. When the bearing sleeve is pre-installed with the mounting hole, if the bearing sleeve and the mounting hole on the beam are not aligned, and the operator does not correct it in time, it is easy for the mounting mating surface of the bearing sleeve and the hole to be squeezed and chipped, resulting in an increased assembly clearance. This makes the outer diameter of the bearing sleeve and the inner diameter of the mounting hole on the beam unable to meet the design interference fit requirements. 2. Even slight deformation of the bearing sleeve will cause the center of the hydraulic cylinder hinge shaft to be non-parallel to the center of the piston rod mounting hole, resulting in poor coaxiality between the hydraulic cylinder piston rod and the cylinder barrel. After the hydraulic cylinder is used, the friction between the piston rod, piston, and cylinder barrel causes wear on the seals and the inner wall of the cylinder barrel, leading to seepage and oil leakage in the hydraulic cylinder. 3. At the same time, due to the compact structure of the rotating frame, one end of the outer side of the hydraulic cylinder mounting beam is suspended, requiring the operator to use a ladder for installation. Due to the limited space inside the rotating frame, there is not enough space for the operator to use a sledgehammer at the other end, resulting in uneven force when striking the tooling plate, causing the inner bearing sleeve and the inner hole of the outer bearing sleeve to be misaligned. 4. The bearing inner ring lacks positioning. When the hinge shaft is installed into the bearing inner ring, the inner ring rotates slightly axially, causing the following problems: the hinge shaft cannot be aligned during installation, and the bearing experiences excessive axial impact force, which can damage the internal structure (e.g., damage to the bearing, or loosening of the bearing). If damage to the bearing's internal structure is not detected and replaced in time, the hinge shaft will shift during cylinder use, resulting in poor coaxiality between the cylinder piston rod and cylinder barrel. Over long-term use, friction between the piston rod, piston, and cylinder barrel causes wear on the seals, leading to oil leakage and other problems in the hydraulic cylinder. 5. Because different operators perform assembly work simultaneously during the assembly process, there are varying degrees of safety hazards when using ladders and sledgehammers (e.g., the ladder is accidentally bumped, the sledgehammer falls off during swinging, or other operators pass by).

[0029] This invention solves the problems of uncontrolled quality, low installation efficiency, and potential quality hazards in long-term use caused by the assembly method of large hinge shaft mounting structures in confined spaces, lack of effective force points, and reliance on manual hammering. Compared with existing technologies, it has the following obvious and substantial features and significant advantages:

[0030] 1. By adopting a separate design for the high and low positioning adjustment and the pressing mechanism, the operability of the present invention is improved, while solving the problems of the difficulty in adjusting the high and low positioning of the hydraulic cylinder and the quality problems caused by the non-alignment pressing of the hydraulic cylinder hinge shaft and the bearing sleeve and the bearing.

[0031] 2. In confined workspaces, by providing effective force points and changing the original transitional assembly method, manual jack pressing is adopted to reduce labor intensity, improve assembly efficiency, and reduce safety hazards during assembly operations.

[0032] 3. Different installation devices can be designed based on this principle, depending on the size of the hydraulic cylinder. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of the present invention;

[0034] Figure 2 This is a structural schematic diagram of the support frame;

[0035] Figure 3 This is a schematic diagram of a bridge-type support structure;

[0036] Figure 4 for Figure 3 Enlarged view of Part I;

[0037] Figure 5 for Figure 3 Enlarged view of Part II;

[0038] Figure 6 This is a diagram showing the usage state of the installation device of the present invention;

[0039] Figure 7 This is a schematic diagram showing the installation of the hydraulic cylinder, rotating frame, and large lifting platform.

[0040] Figure 8 for Figure 7 AA section view;

[0041] Figure 9 for Figure 7 BB section view;

[0042] Figure 10 for Figure 7 Perspective view;

[0043] Figure 11 for Figure 7 Top view. Detailed Implementation

[0044] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0045] Figure 1-5 The device of this invention mainly comprises: an adjustable support frame 1, a bridge support 2, a contoured semi-circular sleeve (i.e., a positioning seat) 3, a manual jack 4, and a bearing sleeve assembly 6. The bearing sleeve assembly 6 includes a bearing sleeve 65 and a bearing 61 whose inner cavity is centered by a bearing positioning sleeve 63. The bearing 61 is mounted on the inner port of the bearing sleeve 65 via a retaining ring, and a pressure plate 64 is clamped on the outer port of the bearing sleeve 65. The pressure plate 64 cooperates with the jack 4. The bearing positioning sleeve 63 is detachably mounted inside the bearing sleeve 65. The bearing positioning sleeve 63 has a radial partition in the middle, and a small screw 66 for disassembling the bearing positioning sleeve is mounted on the radial partition.

[0046] Adjustable support frame mainly includes Figure 2 The system comprises a front sling 12, a rear sling 13, a rotating lifting ring 14, a height adjustment screw 15, a locking adjustment screw 16, and two frame bodies 11. After assembly, the front sling 12 and rear sling 13 lift the hydraulic cylinder 8, allowing for precise height adjustment and positioning of the cylinder 8. The adjustable support frame is then locked in place using the locking screw 16. One end of each frame body 11 rests directly on the rotating beam, while the other end is secured to the beam via a vertical plate. The locking screw 16 on the rotating plate ensures the frame body 11 remains vertical. The support frame itself is constructed by welding the front and rear frame bodies 11 to the lifting beam. The front and rear frame bodies 11 are made of rectangular steel pipes and plates, minimizing weight while ensuring load-bearing capacity. The front and rear lifting rings are connected by slings via locking buckles.

[0047] The above Figure 3 The bridge support 2, the contoured semi-circular sleeve 3, the manual jack 4, and the bearing positioning sleeve 63 are used together to form a press-fitting device for the hydraulic cylinder hinge shaft and the bearing sleeve. The contoured semi-circular sleeve 3 and the bearing sleeve 65 containing the bearing 61 are pre-installed in the mounting holes of the rotating frame 7. One side of the hydraulic cylinder 8 is adjusted so that the contoured semi-circular sleeve 3 is inserted, and the other side is aligned with the bearing center hole. The bridge support 2 provides a support point in the confined space, and the manual jack 4 presses the bearing sleeve 65 into place. The bearing positioning sleeve 63 is mainly used to ensure that the center holes of the bearing 61 and bearing sleeve 65 are coaxial. The bridge support 2 is mainly welded from steel plates, and weight is reduced by opening holes while ensuring sufficient strength.

[0048] The above Figure 1 , Figure 4 The central tensioning mandrel 5 is mainly used for positioning the piston rod lug 81 of the hydraulic cylinder and the mounting part 91.

[0049] During installation, first hoist the hydraulic cylinder 8 to be installed using the adjustable support frame 1 (note the installation direction of the hydraulic cylinder), then hoist the adjustable support frame 1 as a whole to the installation position. After initially aligning the hydraulic cylinder hinge shaft with the mounting hole, lock the adjustable support frame 1 with the locking screw 16.

[0050] The contoured semi-circular sleeve 3 and the bearing sleeve 65, which contains the bearing 61 and is centered using the bearing positioning sleeve 63, are pre-installed in the mounting hole 71. The bridge support 2 is then hoisted to... Figure 3 The installation mating surface is shown, with the pressure plate 64 at the end of the preload bearing sleeve 65 of the jack 4 pressed first.

[0051] Adjust the height adjustment screw 15 on the support frame 1 until one end of the hydraulic cylinder hinge shaft is fully inserted into the arc of the contour semicircular sleeve 3. After aligning the other end of the hinge shaft with the center of the bearing hole, press the jack 4 by hand to press the bearing sleeve assembly 6 into place. Remove the bridge support 2 and the contour semicircular sleeve, rotate the bridge support 180°, and press the other end of the hydraulic cylinder hinge shaft into place with the bearing sleeve, which is centered using the bearing positioning sleeve, following the above method.

[0052] like Figure 6 As shown, after pre-aligning the piston rod lug 81 of the hydraulic cylinder with the mounting part 91 of the large lifting platform 9, the piston rod of the hydraulic cylinder 8 is pre-installed with the mounting part 91 of the large lifting platform 9 using the tensioning centering shaft 5 (note that the installation direction of the tensioning centering shaft is opposite to that of the shaft required by the product). The shaft, which has been cold-installed, is then inserted sequentially from the chamfered end of the tensioning centering shaft 5 to complete the assembly of the hydraulic cylinder 8. The mounting part 91 is the support point of the large lifting platform 9.

[0053] The examples described above are merely preferred methods and implementation methods of the present invention. Those skilled in the art can understand the content and technical principles of the present invention and implement it accordingly. However, any improvements and modifications derived from this invention should be considered within the scope of protection of the present invention.

Claims

1. A method for installing a large hydraulic cylinder in a confined space, characterized in that: Includes the following steps: A) First, the cylinder (8) to be installed is hoisted using the adjustable support frame (1). The cylinder (8) is in an inclined state when hoisted by the adjustable support frame (1). Then, the adjustable support frame (1) is hoisted as a whole to the installation position on the rotating frame beam. After the initial adjustment of the cylinder hinge shaft and the mounting hole (71) are aligned, the adjustable support frame (1) is locked with the locking screw (16). The rotating frame beam forms the inner cavity of the rotating frame, and the cylinder (8) is placed in the inner cavity of the rotating frame. The positioning seat (3) and a bearing sleeve assembly (6) to be installed are pre-installed in the mounting holes (71) on the rotating beam. The bridge support (2) is hoisted onto the rotating beam. One arm of the bridge support (2) is clamped to the positioning seat (3). The jack (4) at the other arm of the bridge support (2) corresponds to the bearing sleeve assembly (6). There is a gap between the jack (4) and the bearing sleeve assembly (6). The jack (4) is pressed by hand to preload the bearing sleeve assembly (6). The two arms of the bridge support (2) are subjected to force. The bridge support (2) is erected on the rotating beam. Adjust the height adjustment screw (15) on the adjustable support frame (1) to completely lower one side of the hydraulic cylinder (8) into the semi-circular sleeve (62) of the positioning seat (3). After aligning the other side of the hydraulic cylinder with the center of the bearing hole, press the jack (4) by hand to press the bearing sleeve assembly (6) into place. B) Remove the bridge support (2) and positioning seat (3) from below the adjustable support frame (1), pre-install another bearing sleeve assembly to be installed at the mounting hole of the positioning seat (3) in step A, rotate the bridge support (2) 180°, and clamp one arm end of the bridge support (2) with the bearing sleeve assembly (6) installed in step A. The jack (4) at the other arm end of the bridge support (2) corresponds to the bearing sleeve assembly to be installed. There is a gap between the jack (4) and the bearing sleeve assembly to be installed. Press the jack (4) to pre-press the bearing sleeve assembly (6) to be installed. The two arms of the bridge support (2) are under force. The bridge support (2) is erected on the rotating beam. Press the jack (4) to press the bearing sleeve assembly (6) to be installed into place. C) After pre-aligning the piston rod clevis (81) of the hydraulic cylinder (8) with the mounting part (91) of the large lifting platform (9), use the tensioning centering shaft (5) to pre-install the piston rod clevis (81) of the hydraulic cylinder (8) with the mounting part (91). The installation direction of the tensioning centering shaft (5) is opposite to that of the shaft required by the product. The shaft after cold installation is inserted into the mounting part of the large lifting platform (9) from the chamfered end of the tensioning centering shaft (5) in sequence, and the tensioning centering shaft (5) is pushed out to complete the assembly of the hydraulic cylinder (8).

2. The method for installing a large hydraulic cylinder in a confined space according to claim 1, characterized in that: The adjustable support frame (1) includes a support frame body, which includes two frames (11). The two frames are connected as a whole by a hoisting beam. The upper ends of the two frames are respectively equipped with mounting seats. The outer side of the mounting seats is equipped with a height adjustment screw (15). The end of the height adjustment screw (15) is connected to a rotating lifting ring (14) for lifting the cylinder barrel of the hydraulic cylinder (8) to be installed in a confined space. The front lifting strap (12) and the rear lifting strap (13) are connected to the rotating lifting ring (14). Two upright plates are welded to the support legs on one side of the two frames. Locking screws (16) are installed on the upright plates on the outer side. The bridge support (2) includes a bridge support frame, with a positioning seat (3) for positioning the hinge shaft at one end of one arm and a jack (4) for pressing the bearing sleeve assembly (6) at the other end of the arm; the positioning seat (3) includes a cylindrical part at the outer end and a semi-circular sleeve part (62) connected to the inner end of the cylindrical part, the inner cavity of the semi-circular sleeve part forming the positioning cavity for positioning the hinge shaft; there is a radially arranged partition (67) between the cylindrical part and the semi-circular sleeve part, and a small screw (66) for disassembling the positioning seat is installed on the partition; a positioning step is provided at the end of the support arm, and the cylindrical part of the positioning seat (3) is locked at the positioning step; The bearing sleeve assembly (6) includes a bearing sleeve (65) and a bearing (61) whose inner cavity is centered by a bearing positioning sleeve (63). The bearing (61) is installed at the inner port of the bearing sleeve (65) via a retaining ring, and the pressure plate (64) is clamped at the outer port of the bearing sleeve (65). The pressure plate (64) cooperates with the jack (4).

3. The method for installing a large hydraulic cylinder in a confined space according to claim 1, characterized in that: Two hydraulic cylinders (8) are installed in the inner cavity of the rotating frame (7). The rotating frame (7) is installed on a frame 1.7 meters above the ground. The large lifting platform (9) is 3.2m*2.4m in size and has a load capacity of 8-10 tons. The rotating frame (7) is mounted on the large lifting platform (9). The cylinder barrel of the hydraulic cylinder (8) is mounted on the rotating frame (7) through the hinge shaft (82). The piston rod clevis (81) is mounted on the mounting part (91) of the large lifting platform (9). The lifting function of the large lifting platform (9) is realized by the extension and retraction of the piston rod. The hydraulic cylinder weighs 360kg and the total length of the hydraulic cylinder is 2600mm when the piston rod is fully extended.

4. The method for installing a large hydraulic cylinder in a confined space according to claim 1, characterized in that: In step B, the bridge support (2) is erected on the rotating beam. Observe whether the inner wall of the bearing bore is aligned with the outer circle of the hinge shaft. If they are not aligned, finely adjust the height adjustment screw (15) until the inner ring of the bearing is aligned with the hinge shaft. After alignment, press the jack (4) by hand to press the bearing sleeve assembly (6) to be installed into place.

5. A large hydraulic cylinder mounting device for confined spaces, applicable to the mounting method as described in claim 1, characterized in that: Includes an adjustable support frame (1) and a bridge support (2) for the hinge shaft of the hydraulic cylinder (8) to be press-fitted into the two mounting holes of the rotating frame (7); The adjustable support frame (1) includes a support frame body, which includes two frames (11). The two frames are connected as a whole by a hoisting beam. The upper ends of the two frames are respectively equipped with mounting seats. The outer side of the mounting seats is equipped with a height adjustment screw (15). The end of the height adjustment screw (15) is connected to a rotating lifting ring (14) for lifting the cylinder barrel of the hydraulic cylinder (8) to be installed in a confined space. The front lifting strap (12) and the rear lifting strap (13) are connected to the rotating lifting ring (14). The bridge support (2) includes a bridge support frame, with a positioning seat (3) for positioning the hinge shaft at one end of one arm and a jack (4) for pressing the bearing sleeve assembly (6) at the other end of the arm.

6. The large hydraulic cylinder installation device in a confined space according to claim 5, characterized in that: The adjustable support frame (1) has two upright plates welded to one side of the two frame legs, and a locking screw (16) is installed on the outer upright plate; the oil cylinder (8) is in an inclined state when lifted by the front sling (12) and the rear sling (13); the front sling (12) and the rear sling (13) are connected to the rotating ring (14) by hooks.

7. The large hydraulic cylinder installation device in a confined space according to claim 5, characterized in that: The mounting base has a bayonet on the inside, and the lifting beam that is locked at the two bayonet points is welded to the two frames as a whole; the end of the height adjustment screw (15) is connected to the sling via a rotating ring (14), and the sling is hooked to the rotating ring (14) via a hook.

8. The large hydraulic cylinder installation device in a confined space according to claim 5, characterized in that: The positioning seat (3) includes a cylindrical part located at the outer end and a semi-circular sleeve part (62) connected to the inner end of the cylindrical part. The inner cavity of the semi-circular sleeve part forms a positioning cavity for the positioning hinge shaft. There is a radially arranged partition (67) between the cylindrical part and the semi-circular sleeve part. A small screw (66) for disassembling the positioning seat is installed on the partition.

9. The large hydraulic cylinder installation device in a confined space according to claim 5, characterized in that: The end of the support arm is provided with a positioning step, and the cylindrical part of the positioning seat is engaged with the positioning step.

10. The large hydraulic cylinder mounting device in a confined space according to claim 5, characterized in that: The bearing sleeve assembly (6) includes a bearing sleeve (65) and a bearing (61) whose inner cavity is centered by a bearing positioning sleeve (63). The bearing (61) is installed in the inner port of the bearing sleeve (65) via a retaining ring, and a pressure plate (64) is clamped in the outer port of the bearing sleeve (65). The pressure plate (64) cooperates with the jack (4). The bearing positioning sleeve (63) is detachably installed in the bearing sleeve (65). The bearing positioning sleeve (63) has a radial partition in the middle, and a small screw (66) for disassembling the bearing positioning sleeve is installed on the radial partition.

Images