112results about How to "Butt tight" patented technology

The invention relates to the technical field of mechanical data processing, in particular to a mechanical experiment data pre-processing method based on a mechanical model. The method comprises the following steps: acquiring a mechanical experiment setting condition and a mechanical experiment measurement target, and carrying out mechanical model calibration establishment to obtain a stress-strain experiment mechanical model; carrying out noise point radius circular filtering processing by recording mechanical experiment parameter data in real time, and carrying out interpolation compensation and standardization processing to obtain mechanical experiment parameter standardization data; performing mechanical experiment fitting processing on the stress-strain experiment mechanical model to obtain stress-strain mechanical experiment fitting output prediction data; performing model prediction error analysis on the mechanical experiment parameter data to obtain stress-strain mechanical experiment model prediction error data; and performing error correction optimization on the mechanical experiment parameter data to obtain mechanical experiment parameter error correction data. The method can improve the quality of mechanical data and the reliability of analysis results.

The invention discloses a double-sealed novel water pump which comprises a pump body and a pump shell, the pump shell is matched with the pump body, a motor is installed at the bottom end of the pump body, an impeller is installed at the top end of the pump body, the output end of the motor is fixedly connected with the impeller, an internal sealing ring is installed on the pump body, and a plurality of annular reserved cavities which are annularly arranged at equal intervals are formed in the pump body. According to the scheme, the cross section of the internal sealing ring is arranged to be in the L shape, the contact area between the internal sealing ring and the pump body and the contact area between the internal sealing ring and the pump shell are increased, and the service life of the internal sealing ring is prolonged; a gap generated between the inner sealing ring and the pump shell can be filled in time in a vibration environment through the arrangement of the annular expansion bag, second-layer sealing is achieved through the arrangement of the outer sealing assembly, the stability of the mounting hole is enhanced, leaked liquid is absorbed through the water absorption ring, and the threaded connection position between the extrusion ring and the pump shell is blocked.

The invention relates to the related technical field of metal welding, in particular to auxiliary butt joint equipment for pipeline welding, which comprises a base, a bearing frame, a folding module, an adjusting module, a middle bearing module, a sensing module, a welding module and a running-in module. The extrusion force between the pipelines is detected in a switching mode, flexible regulation and control are conducted according to the pressure detection result, the butt joint pressure of the pipelines is made to be in a proper range, gaps can be reduced through the proper extrusion force, the welding quality is improved, meanwhile, air holes generated in the welding process are reduced through extrusion, a better molten pool shape can be formed, and the welding quality is improved. In addition, in order to ensure uniform butt joint between the pipelines, the running-in modules are used for carrying out rotary butt joint between the pipelines, uniform attachment between planes of the pipelines is ensured, the relative positions between the pipelines can be adjusted more accurately by rotating the pipelines, non-uniform gaps on the butt joint faces can be eliminated easily, and the welding quality of the pipelines is improved. Therefore, the butt joint is tighter.

The invention discloses a precision detection device for valve gearbox gear production, and the device comprises a detection platform which comprises a detection structure and a lifting structure which are disposed on a platform surface, and a feeding assembly which is disposed at the front side of the detection platform and is used for intermittently conveying gears to the rear side, the feeding assembly comprises an electric conveying frame and a belt installed on the electric conveying frame, a plurality of spacing bars arranged at equal intervals are installed on the belt, and guide plates used for guiding a to-be-detected gear to be discharged backwards along the central axis are connected to the two sides of the electric conveying frame in an inserted mode. And the distance between the bottom of the guide plate and the top face of the belt is larger than the height of the spacing bar, and the conveying structure is arranged on the rear side of the feeding assembly. In the whole operation process, the manual intervention time can be effectively shortened, the detection period is shortened, meanwhile, safety is improved, in addition, bidirectional clamping and fixing can be conducted along the inner ring and the outer side of the gear to be detected, and the stability of follow-up rotation of the gear to be detected and the reliability of a detection result are guaranteed.

The invention relates to the technical field of laser processing, in particular to a fully-sealed adjustable laser beam expander which comprises a sealing cover, an air inlet pipe is communicated with the peripheral wall of the sealing cover, a plurality of air outlet pipes are communicated with the peripheral wall of the sealing cover, and two sliding rods are welded to the side wall of an inner cavity of the sealing cover. Sliding blocks are arranged on the peripheral walls of the two sliding rods in a sliding mode, a beam expander body is welded between the two sliding blocks, a plurality of limiting rods are welded to the annular wall of an inner cavity of the sealing cover and circumferentially distributed on the annular wall of the inner cavity of the sealing cover at equal intervals, and telescopic air bags are arranged between the limiting rods; a sealing rubber strip adheres to the side wall of the sealing cover, a plurality of first air outlet holes are formed in the peripheral wall of the sealing rubber strip, the arranged telescopic air bag expands after absorbing heat, the expanded telescopic air bag can abut against the contact face of the sealing cover and the laser cutting machine, and therefore the sealing effect of the contact face of the sealing cover and the laser cutting machine is enhanced.

The invention discloses a rainwater collecting and recycling treatment device, and relates to the technical field of rainwater treatment.The rainwater collecting and recycling treatment device comprises a plurality of splicing mechanisms used for building a rainwater collecting pool, the splicing mechanisms are internally provided with joining mechanisms for improving the supporting strength of the splicing mechanisms, and the splicing mechanisms are internally provided with joining openings. The first mounting pipe and the first taper pipe are connected in an inserted mode, tight butt joint between two parts is ensured, the first mounting pipe is inserted into the first taper pipe, the contact area is increased, the stability of the joint is improved, and the connecting block is clamped with the clamping pipe and the second clamping groove, so that the clamping effect is improved through the clamping mechanism. According to the connecting structure, the connecting blocks can be firmly spliced together to form a supporting net rack with high integrity, and when a plurality of cross-shaped connecting blocks are spliced together, the supporting capacity of the butt joint position of the first taper pipe is greatly enhanced, and deformation or breakage caused by water pressure or external loads is prevented.

The invention discloses a device and a method for testing durability of a fuel automobile valve, and provides the following scheme for solving the problems that in the prior art, when a valve is repeatedly opened and closed through mechanical operation equipment, the mechanical operation direction needs to be continuously changed, and the mechanical operation equipment is likely to break down due to long-term adjustment, so that the test is interrupted. Comprising a detection table, lifting rods are fixedly connected to the four corners of the top of the detection table, the tops of the four lifting rods are fixedly connected with the same top frame, and a test assembly is arranged at the bottom of the top frame. According to the fuel automobile valve durability testing device and method, in the testing process, the driving motor rotates in one direction all the time, damage caused by excessive direction adjustment is avoided, the integrity of the device in the testing process is ensured, it is ensured that the testing process can be smoothly completed, and the testing efficiency is improved. And the accuracy of the test result is ensured.

The present invention discloses a multifunctional welding platform for automobile parts, which relates to the field of welding technology. Nowadays, welding is involved in the processing of automobile parts. Automobile parts are welded by welding platforms. Sparks are generated during the welding process. The generated sparks are small particles generated by arc or high-temperature molten metal splashing. Spark splashing can cause damage to the surrounding environment. Sparks contain various metal particles, which may drift and settle in the surrounding environment. If they fall to the area to be welded, it will cause welding spot pollution and affect the subsequent welding quality. The present invention not only isolates the welding area and prevents spark splashing through the combination of a hot air blower and a covering cover through the processing component, but also uses a wiping belt and a hot air flow to preheat the area to be welded, so as to clean it before welding and improve welding efficiency and quality. In summary, the platform significantly improves the fixity, precision and processing efficiency of the workpiece during welding, while effectively ensuring the welding quality.

The utility model is applicable to the technical field of sewage pipeline equipment, and provides a municipal sewage pipeline reinforcing device which comprises a fixing ring and a base, the fixing ring is fixedly arranged on a pipeline, the municipal sewage pipeline reinforcing device further comprises a reinforcing structure arranged on the base, the reinforcing structure comprises a butt joint seat used for connecting two pipelines and a tensioning assembly abutting against the fixing ring, and the tensioning assembly is arranged on the base. The reinforcing structure further comprises a positioning assembly used for positioning the tensioning assembly and a moving assembly used for driving the tensioning assembly to move. And the supporting seat is used for supporting the pipeline, and the supporting seat and the butt joint seat are connected with the base through adjusting assemblies. According to the pipeline butt joint device, tight butt joint of two pipelines can be achieved by arranging the reinforcing structure, the height of the support and the butt joint base is adjusted by arranging the adjusting assembly, and therefore the pipeline butt joint device is suitable for different terrains and high in flexibility.

A concrete nondestructive testing device comprises a supporting base, a lifting part is arranged on the supporting base, a middle rotating part is rotatably arranged on the upper portion of the lifting part, a reciprocating feeding part is arranged on the middle rotating part, an ultrasonic supporting table is arranged on the reciprocating feeding part, and a plurality of ultrasonic testing heads are arranged on the ultrasonic supporting table. According to the ultrasonic testing head, the lifting part is adopted to realize actions in the height direction, the middle rotating part is adopted to realize angle adjustment, and the reciprocating feeding part is adopted to realize actions in the front-back direction, so that the ultrasonic testing head can be tightly propped against a concrete part to be measured.

The utility model provides an outdoor anti-freezing plastic pipe, which relates to the technical field of plastic pipes and comprises a plastic pipe body, a plurality of protective heat preservation devices are arranged on the outer surface of the plastic pipe body, each protective heat preservation device comprises two protective blocks and two screw hole blocks, splicing devices are arranged on the outer surfaces of the protective blocks, and the splicing devices are connected with the screw hole blocks. According to the plastic pipe, the protection and heat preservation device is arranged, the outer surface of the plastic pipe body can be completely wrapped with two protection blocks, an aluminum foil piece and heat preservation cotton, the temperature of the outer surface of the plastic pipe body is increased, and when the external temperature of the plastic pipe body is reduced, the plastic pipe body is prevented from being damaged. The outer surface of the plastic pipe body is not easy to freeze, dry, crack and damage, so that the maintenance and replacement frequency can be reduced, the cost and the replacement time are saved, and meanwhile, the thermal insulation cotton and the aluminum foil can lock the temperature of the outer surface of the plastic pipe body, so that water flow in the plastic pipe body is smooth, and the plastic pipe is convenient to use.

The invention belongs to the technical field of insulators, particularly relates to a cylindrical head suspension insulator, and aims to solve the problems that in the prior art, oil stains and dust are easily accumulated on the surface of an insulator after the surface of the insulator is exposed outside for a long time, flashover phenomena are easily generated, and then the insulator is easily damaged. Comprising a suspension mechanism fixed to the lower surface of the end of a mounting channel steel, the suspension mechanism comprises a first clamping piece fixed to the lower surface of the mounting channel steel, a second clamping piece is clamped to the lower surface of the first clamping piece, a knob insulator body is fixed to the lower surface of the second clamping piece, and a plurality of large discs with the same diameter are arranged in the middle of the knob insulator body. The cleaning device can cooperate with the arrangement of an arc-shaped plate in wind and rain to enable a brush rod in the cleaning mechanism to brush on the surface of the large disc in a swinging manner, so that the surface of the large disc at the position can be cleaned up, surface disruptive discharge caused by formation of a discharge loop on the surface of an insulator is prevented, and the service life of the insulator can be prolonged; and the maintenance period can be greatly reduced.

The invention provides an electrical connection structure, a preparation method thereof, medical wearing equipment and a use method thereof, the electrical connection structure comprises a connection seat, a conductive connection piece and a conductive switch, the connection seat comprises a first connection base and a second connection base which are rotatably connected with each other, so that the connection seat is in an unfolded state or a closed state; the conductive connecting piece and the conductive switch are both embedded in the first connecting base, and the connecting base is used for placing the second electronic element in an unfolded state; the connecting base abuts against the circuit board and the second electronic element in the closed state, one end of the conductive connecting piece is used for being electrically connected with the circuit board, the other end of the conductive connecting piece is used for being electrically connected with the second electronic element, and the conductive switch is used for being electrically connected with the circuit board. The requirements of electrical connection, sealing and waterproofing, circuit starting and the like can be met at the same time.

The utility model relates to the crimping technical field, concretely relates to a crimping structure, include: the department of inserting, is used for inserting in the department of inserting hole of PCB board, force department is as the force point of providing pressure, when force department force carries out crimping operation, the department of inserting moves along its axial motion and pin needle contact in the department of inserting hole, produces extrusion to pin needle, simultaneously, the department of inserting occurs perpendicular to its department of inserting direction's deformation, makes the department of inserting fixed on the PCB board personally, and pin needle crimping is fixed in the PCB board, in the utility model, pin needle is installed on the PCB board through the mode of crimping, and the influence of whisker caused by soldering to the stability of equipment is eliminated.

The utility model relates to an air tightness detection device for a corrugated hose, which comprises a detection pool and is characterized in that the detection pool is connected with a plurality of groups of detection devices which are uniformly distributed along the longitudinal direction; each group of detection devices comprises two end sockets which are oppositely arranged left and right and are fixedly connected with the side wall of the detection pool, one end, located in the detection pool, of each end socket is a conical joint, each end socket on the left side is integrally and coaxially provided with an air inlet pipe, the inlet end of each air inlet pipe is fixedly connected with the outlet end of a guide pipe, and the outlet end of the guide pipe is fixedly connected with the air inlet pipe. The inlet end of each guide pipe is fixedly communicated with the outlet end of an electric air pump; a driving device fixedly connected with the inner wall of the detection pool is arranged on the rear side of each conical joint, each group of driving devices drives two fastening clamps which are oppositely arranged up and down relative to the conical joint on the corresponding side, each fastening clamp is arranged in an arc shape, and the inner edge of each fastening clamp is fixedly connected with an arc-shaped sealing soft lining.

The present invention relates to the technical field of underground pipelines, and in particular to a prefabricated pipe gallery for water conservancy projects, comprising a supporting component, including two pipeline bodies, a first flange arranged on the pipeline body at the left end, a second flange arranged on the pipeline body at the right end, an annular groove arranged on the first flange and the second flange, and a sealing ring arranged on the annular groove; a closing component, including a plugging component arranged on the first flange and the second flange, a rotating component arranged on the first flange and the second flange, a transmission component arranged on the rotating component, and a limiting component arranged on the rotating component; a reinforcing component, including a pushing component arranged on the rotating component, and an elastic component arranged on the pushing component. The device described in the present invention can directly move a block on the flange to close the pipeline without finding a valve to close, and is easy to use.

The present invention relates to a power battery module separation device, including a processing table, a U-frame, a tweezer component and a limiting component; a storage cavity is reserved in the processing table, the limiting component is arranged on the storage cavity, the U-frame is telescopically arranged on the processing table, the inner edge of the U-frame is multi-directionally arranged with a carrier, and the tweezer component is telescopically arranged at the lower position of the carrier. After the linkage pad is squeezed with the side of the battery, under the action of the inclined part, the linkage pad can be retracted into the storage cavity, at this time, the rack will link the gear to rotate, and the gear will link the piston to telescopic movement upward through the linkage rod when rotating. The piston can drain the gas in the suction cup into the hollow table under the action of negative pressure. At this time, the suction cup and the upper surface of the battery are more closely docked, so as to ensure the stability of the battery when it is taken out in a suspended state.

The utility model belongs to the technical field of door locks, and particularly relates to a stable door lock which comprises a device body, a mounting plate mounted on the device body, a door handle bearing rotationally connected to the device body, a door handle rotationally connected with the door handle bearing and a first bearing mounted in the device body. One end of the first gear is fixedly connected with the door handle, the other end of the first gear is supported on the first bearing, the second gear is in meshed transmission connection with the first gear, the switch bolt is fixedly connected with the second gear and can be rotatably plugged, and the third gear is in meshed transmission connection with the second gear; rotation of the door handle is converted into insertion and extraction motion of the bolt through the gear mechanism, operation is easy and convenient, no complex power source is needed, the bolt can be driven to be locked or released only by manually rotating the door handle, the exquisite gear transmission design is adopted, rotation of the door handle can be accurately converted into linear motion of the bolt, and the safety performance of the door handle is improved. Therefore, the door handle and the bolt move accurately and are operated accurately and reliably.

The tunnel cable groove construction device comprises a machine shell and a chiseling mechanism, openings are formed in the periphery of the machine shell, and driving wheels are installed at the bottom of the machine shell; the scabbling mechanism comprises a first scabbling assembly and a second scabbling assembly. A lifting plate is installed in the machine shell in an up-down sliding mode. The first scabbling assembly is installed at the bottom of the lifting plate, and a lifting driving assembly is installed on the machine shell. Moving plates are symmetrically arranged on the top surface of the lifting plate left and right, the two moving plates are horizontally and slidably mounted at the ends of the two sides of the lifting plate, and a horizontal driving assembly is arranged between the moving plates; the outer edge of the moving plate is rotationally connected with a rotating plate, the second chiseling assembly is installed on the outer end face of the moving plate, and a supporting assembly for supporting and fixing the rotating plate is installed on the moving plate. The device can be used for scabbling cable grooves with different specifications and sizes, and can effectively perform scabbling construction on the tunnel side wall and the groove base at the same time, so that the construction efficiency of the cable grooves is remarkably improved, and the construction period is greatly shortened.

The utility model discloses a special-shaped plate chamfering wheel and relates to the technical field of chamfering wheels, the special-shaped plate chamfering wheel comprises a chamfering wheel body and a flange plate, a shaft sleeve penetrates through the middle of the chamfering wheel body, a lower shell is arranged below the chamfering wheel body, and inserting rods are annularly distributed on one side, close to the lower shell, of the chamfering wheel body at intervals. An inserting groove is formed in the side, close to the inserting rod, of the lower shell, the outer side of the shaft sleeve is sleeved with a threaded sleeve in a threaded mode, and a cutter block is arranged above the chamfering wheel body. According to the special-shaped plate chamfering wheel, when the chamfering wheel is abraded and needs to be replaced, a threaded sleeve is rotated firstly, the threaded sleeve is detached from a shaft sleeve, then a limiting rod is pulled towards one side, the limiting rod drives a reset spring to contract, one end of the limiting rod is driven to be separated from a mounting hole, then a chamfering wheel body is pulled upwards, and an inserting rod is separated from an inserting groove; and the chamfering wheel body can be quickly detached and replaced without detaching the flange plate, so that the convenience of the chamfering wheel is improved.

The utility model discloses a coupler cavity fastening screw tool, which relates to the technical field of coupler cavity fastening screws, and comprises a fastening screw tool main body, the upper end of the fastening screw tool main body is connected with a U-shaped limiting frame, the right side of the U-shaped limiting frame is connected with a coupler, and the left side of the U-shaped limiting frame is provided with an output port jack. The coupler cavity fastening screw tool comprises a fastening screw tool body, a U-shaped limiting frame is arranged at the upper end of the fastening screw tool body, a first output port through groove is formed in the back face of the U-shaped limiting frame, a clamping assembly is arranged at the upper end of the fastening screw tool body, a vertical plate is arranged at the upper end of the U-shaped limiting frame, a fixing assembly is arranged at the upper end of the vertical plate, and supporting legs are connected to the lower end of the fastening screw tool body. The clamping plate is arranged on the screw fastening tool body, the clamping plate can be driven to move front and back through stretching or compression of the spring, the coupler can be clamped, a worker can conveniently screw a screw, couplers of different sizes can be fixed, the applicability is high, and the flexibility is high.

The invention discloses a management coordination method and system based on labor demand analysis, and relates to the technical field of management coordination, and the method comprises the steps: carrying out the analysis based on historical labor demand information, and outputting a first labor prediction result; performing analysis based on the technical change information of the labor personnel, and outputting a technical change prediction result of the labor personnel; performing analysis based on the enterprise development information, and outputting an enterprise development prediction result; performing analysis based on the market demand change information, and outputting a market demand change prediction result; and in combination with the first labor force prediction result, the labor personnel technology change prediction result, the enterprise development prediction result and the market demand change prediction result, outputting a comprehensive labor force demand prediction result of each prediction stage, further outputting a management coordination scheme, and performing adjustment response on the labor force demand change of each stage. Accurate prediction and flexible management coordination of enterprise labor demands are realized, and enterprise operation efficiency and resource utilization efficiency are significantly improved.

The utility model relates to a membrane bag which comprises a filtering part and a peripheral packaging part arranged on the peripheral side of the filtering part in a wrapping mode, and the filtering part comprises a screen and a filtering membrane which are arranged at intervals. The screen is provided with a through hole and a packaging hole, the peripheral packaging part is provided with two oppositely arranged peripheral packaging part end faces, at least one side end face of the peripheral packaging part is provided with an abutting area, and the abutting area protrudes out of the peripheral packaging part end faces; the projection area of the abutting area on the end face of the peripheral packaging part is smaller than the area of the end face of the peripheral packaging part, so that a receding area can be formed between the side wall of the abutting area and the end face of the peripheral packaging part, and the packaging structure has the advantages that the sealing effect is good, and the supporting strength of the peripheral packaging part is not affected.

The utility model relates to the field of electronic cigarette discloses an air switch air channel structure of preventing condensate, including zinc alloy shell, PCB assembly, air adjusting device, POD oil storehouse base and data line storage mechanism, data line storage mechanism includes fixed box, the fixed box in top end fixed setting has micro motor, the micro motor output fixedly covers and sets up one no. In the utility model, the data line does not need to be carried additionally, the problem that traditional data line is lost or forgotten can be effectively avoided, after charging, the micro motor can be started to wind the data line neatly back to the outer end of the first binding roller.

The utility model relates to the technical field of hydraulic tongs, in particular to an intelligent interlocking safety device which comprises a hydraulic tong body, a height adjusting mechanism is arranged below the hydraulic tong body and comprises a bottom plate arranged below the hydraulic tong body, and the top end of the bottom plate is fixedly connected with a base. An adjusting rod is slidably connected to the top of the base, a plurality of limiting holes are formed in one side of the adjusting rod, an inner groove is formed in one side of the base, a linkage block is arranged in the inner groove, a plurality of protruding blocks are fixedly connected to the side, facing the adjusting rod, of the linkage block, and the protruding blocks are matched with the limiting holes. According to the hydraulic clamp, the hydraulic clamp body is matched with the height adjusting mechanism, so that an operator adjusts the height of the hydraulic clamp body through the adjusting rod when using the hydraulic clamp body, and pushes the linkage block into the limiting hole in a mode of treading the pedal to enable the linkage block and the limiting hole to be clamped with each other; therefore, the height of the adjusting rod is limited, the output of an operator is reduced, and the operator is prevented from fatigue.

This utility model relates to a rod positioning and bonding fixture for processing hemispherical resonators, including a fixture base. The fixture base is equipped with a side frame, a rod support assembly, and an automatic glue applicator. The side frame has a clamping member for holding a reference rod. The rod support assembly supports the molten quartz rod and has a drive mechanism for aligning the end of the molten quartz rod with the end of the reference rod. The automatic glue applicator is located between the clamping member and the rod support assembly and is used to apply glue to the end of the reference rod. In this utility model, the clamping member on the side frame fixes the reference rod to provide a stable processing reference; the rod support assembly supports the molten quartz rod and achieves precise alignment with the reference rod through the drive mechanism, ensuring coaxiality and contact accuracy between the two; the automatic glue applicator, located between the two, can accurately apply glue to the end of the reference rod, ensuring reliable and consistent bonding.

This invention provides a structural template positioning device, comprising at least two multi-sided frames, support members, and locking members. Each side of the multi-sided frame has a groove protruding outward along its length for positioning and inserting template panels, allowing multiple template panels to be flat against the inner walls of the multi-sided frame. The support members are detachably installed between two adjacent multi-sided frames, providing support between them at fixed intervals. The locking members are disposed on the grooves and have a movable end that moves along the length of the groove, for abutting against the side end face of the template panel. This invention forms a positioning base for the structural template through the construction and fixing of the frame. Template panels are then inserted into the grooves for rapid insertion into the positioning positions, forming a flat, box-like structure. Tightening the locking members ensures a tight fit between the template panels, achieving rapid positioning, assembly, and reinforcement, saving labor and improving construction efficiency.

The utility model discloses automatic welding equipment for metal components, which comprises two supports and a turnover horizontal frame, mounting blocks are mounted at two ends of the turnover horizontal frame, the mounting blocks are fixedly connected with the tops of the supports through bearings, a first positioning mechanism for positioning a first metal piece is arranged on the turnover horizontal frame, and a second positioning mechanism for positioning a second metal piece is arranged on the turnover horizontal frame. A second positioning mechanism for positioning a second metal piece is arranged on the overturning horizontal frame; the turnover horizontal frame is provided with a welding window at the joint of the first metal piece and the second metal piece; the first metal piece and the second metal piece which need to be welded are fixed through the first positioning mechanism and the second positioning mechanism, and then the welding window is formed in the butt joint position of the first metal piece and the second metal piece, so that a worker and a welding robot can operate conveniently; and in addition, the overturning horizontal frame can be overturned, so that the welding position is rotated, and welding is facilitated.