Devices for fastening and adjustment of technological equipment. Methods and means for aligning equipment during installation with a given accuracy. Examples of some projects completed by ngky in the industrial alignment and alignment segment
LAYOUT OF SUPPORT STRUCTURES. INSTALLATION AND ALIGNMENT OF THE EQUIPMENT
Before installing the equipment, perform markup axes and equipment position on building structures in accordance with the project. Then the equipment is installed on the supporting structures.
Installation equipment is called the process of moving it by lifting means or rigging equipment from the equipment storage location at the installation site to the location on the supporting structures provided for by the project. The equipment is mounted on wooden beams, on metal pads, on jacks or screws, or directly on support structures. After installation, the equipment is verified.
reconciliation called determining the position of the equipment relative to the axes, supporting structures and adjacent equipment according to the markings made and bringing it into line with tolerances for deviations that do not exceed the requirements of the installation instructions. Sometimes equipment alignment is combined with its installation.
Marking of supporting structures.
It is driven relative to the mounting axes.
Mounting axes coincide with the horizontal projections of the axes of machines and devices and are located in the same plane 100-200 mm above the installation area. Mounting axes are horizontal projections of the axes of shafts, rotors, drives, axes of symmetry of machines, cylinders, electric motors, etc. intersecting with them. Mounting axes are designated by string tension. The projections of the axes, shafts and rotors of the main equipment are called the main mounting axes. The main mounting axes usually coincide with the axes of the foundation and the same strings are used to designate them as in the manufacture of foundations.
The position of the axes on the foundations is fixed by installing dies (slats), and elevation marks - by installing benchmarks.
die is a metal plate measuring 80 X 150 mm with an anchor rod welded to it. The anchor rod during the installation of the plate is welded to the reinforcement of the foundation and concreted. On the die, a point is applied with a core with an accuracy of at least ± 1 mm and circled with a triangle with red paint.
Benchmark is a rod with a semicircular head, which is also welded to the reinforcement of the foundation and concreted. The top point of the benchmark head corresponds to the design height mark with an accuracy of ±0.5 mm. Dies and benchmarks are placed in places where they would be available for measurements and after installation of equipment and communications. All markings relative to the axes on the structures are done with strokes of a scriber or lines of paint.
Tool for marking and reconciliation.
When marking and aligning equipment, a variety of tools and fixtures are used. When checking verticality, plumb lines are used, horizontalness - locksmith (bar) levels with a division value of 0.1 or 0.2 mm per 1 m. When checking slopes, levels with an adjustable position of the ampoule are used. Frame levels are used to check the horizontal and vertical. To measure linear dimensions, metal rulers with a division value of 1.0 and 0.5 mm and a length of up to 1000 mm are used, and tape measures are used to measure large distances. The error of the rulers should not exceed ± 0.2 mm with a length of 1 I. To measure the gaps, probes with a length of 50, 100 and 200 mm are used with a set of plates with a thickness of 0.003 to 2 mm and an error of not more than 0.01 mm. Calipers and depth gauges are used to measure external and internal linear dimensions with an error of not more than 0.05 mm. For accurate linear measurements with an error of not more than 0.01 mm, micrometers are used with measurement limits from 0 to 600 mm (after 25 mm to 300 mm and then after 100 mm), and for internal measurements - calipers (inside gauges). When measuring the runout of rotating parts, the deformation of parts when tightening bolts, when aligning shafts and couplings, indicators with a dial-type scale with a division value of 0.01 and 0.002 mm are used. When checking the height difference of remote points, transferring elevations in adjacent rooms, marking the slopes of pipelines being laid, hydrostatic levels are used with a measurement error of up to 1 mm, and with the use of a hydrostatic measuring head, no more than 0.02 mm. When marking work on installation, as well as when aligning large equipment, geodetic (optical) instruments are widely used - theodolites and levels.
Installation of equipment on the foundation
Before installing the equipment, the upper cleaned surface of the foundation is cut with a chisel, the walls of the wells are thoroughly cleaned and washed with water, oily places are cut down. They mark the places for laying metal linings or installing jacks and carefully align them: make an additional notch and rub in with a level check (no more than 3 divisions at a division price of 0.1 mm per 1 m). The places where the frame adheres to the linings are cleaned with a file or a cleaning machine.
Then, beams or rollers are laid on the foundation in such a way that the ends of the foundation bolts do not interfere with the movement of the equipment frame and the alignment of the axes of the holes in the frame with the axes of the blind bolts or the axes of the wells, after which the equipment is lowered onto the beams or rollers by a crane.
Equipment alignment. When reconciling equipment, installation bases are used, which are divided into support and calibration bases.
Support bases are the surfaces of frames and housings, beds and legs of the equipment, on which the equipment rests when installed on support structures or attached to vertical or ceiling support structures.
Calibration bases are used for instrumental verification of the position of equipment. Verification bases are equipment surfaces specially processed and specified in the manufacturer's documentation. In most cases, shaft surfaces, housing connectors, end surfaces of pulleys, couplings, etc. are used as verification bases.
In the process of alignment, the deviations of the position of the equipment from the design elevation, from horizontality or verticality, as well as deviations from the alignment, parallelism or perpendicularity of its axes with the drive are measured.
Equipment reconcile for compliance with the height mark and horizontal on flat or wedge pads (Fig. 9, a) or unlined method.
Number of linings in a package
The number of linings in the package should be minimal, but not more than five. The slope of the wedge pads is 1: 10 or 1: 20. Before installing the equipment, the pads are checked with a control ruler with a bar level. Linings are placed as close as possible to the foundation bolts, without blocking the wells. After alignment for horizontal (deviation no more than 0.3 mm per 1 m), the linings in the packages are tacked to each other by electric welding.
The unsupported method involves the use of screw, wedge or hydraulic jacks, adjusting (adjusting) forcing screws, adjusting (adjusting) nuts, and when installing equipment with machined mounting surfaces - by installing it on rigid supports.
Jacks for alignment are installed in four places of the frame. After alignment between the frame and the supporting surface of the jacks or pads, a probe 0.05 mm thick should not pass.
The use of set screws allows you to combine the installation and alignment of equipment. Before lowering the equipment onto the foundation, the screws are screwed into the frame so that they protrude beyond its supporting surface by the same amount (10-30 mm). Having lowered the equipment with a crane onto the foundation, alternately adjust its position with screws, achieving horizontalness with a deviation of no more than 0.3 mm per 1 m, if there are no more stringent requirements in the technical documentation.
After the equipment is aligned, the position of the set screws is fixed with lock nuts and the foundation is poured. Before gravy, the threaded part of the screws is fenced off with formwork or wrapped with thick paper. After pouring and setting of the concrete, the set screws are unscrewed 1-2 turns before tightening the foundation bolts.
When installing equipment of a large mass, the frame is aligned with the help of set screws, stacks of plates are placed near the foundation bolts, they are checked with a probe to fit them to the frame and then they are seized by electric welding.
Similarly, align the equipment with set nuts with or without Belleville washers if the foundation bolts are embedded in the foundation array.
When installing equipment on rigid supports, horizontal alignment is not carried out, since the mounting plates of the supports are aligned when embedded in the foundation.
Centering
Alignment(centering) of machines is carried out different ways depending on the design of the coupling, as well as on the speed and power of the machine. When centering, they take the car for the base and, after aligning its frame, checking the end and radial runout of the shaft and the coupling half, the electric motor is centered with rack-mount indicators. Usually, the electric motor is mounted on a frame on a skid, which allows it to be moved in a horizontal plane in two directions. In a vertical position, when aligning the alignment, the electric motor is moved with set screws. The tolerance for radial runout is 0.01 - 0.02 mm for shafts, 0.03-0.04 mm per 100 mm radius for sleeve and finger couplings.
There are such types of misalignment as the parallel displacement of the axes 5 and misalignment, or fracture of the axes BUT. Parallel displacement with the same diameter of the coupling halves can be measured with a feeler gauge and a rigid ruler. The misalignment of the axes is judged by the change in the end (axial) clearance a between the coupling halves when the shaft is rotated with respect to the diameter D, where these measurements are taken.
If the coupling halves have a complex configuration or the diameters of the shafts or coupling halves differ in size, the radial and end clearances are measured with a feeler gauge or indicators between the mounting locations of the fixtures. With correctly performed measurements, the radial clearances in the vertical and horizontal planes are equal to: S1=S2, Sz \u003d S 4. (see source)
Axes misalignment
The misalignment of the axes is calculated from the average values of the gaps a between the ends of the coupling halves and the gaps corresponding to them on the fixtures. Measurements are taken at four points 1,2,3,4 and in four positions I II III IV, turning both shafts by 90 ° and recording the values in the tables (Fig. 10 c).
Negative values indicate that the axis is skewed up or to the left.
The gaps are measured with the foundation bolts tightened. After the installation is completed and the foundation is grouted, the final alignment is carried out and the measurement results are recorded in the machine log or in the act of commissioning.
Checking for perpendicularity or parallelism the axes of the shafts of machines and the drive are performed using strings, rulers, thickness gauges, squares, indicators (Fig. 11 a, b).
The parallelism of the axes is checked by measuring the distance between the axes. The distances between the axles must be the same. The perpendicularity of the axes can be checked according to the Pythagorean law: putting aside 3 and 4 linear measures on the axes, as on the legs, measure the hypotenuse, which should be equal to 5 linear measures (Fig. 11 c, d).
Verticality devices, columns, shafts are adjusted using plumb lines, as well as measuring the distances from them to the equipment (Fig. 11 e).
Alignment of internal bores mounted parts are aligned with a string stretched along the axis of the bore of the base part (fig. 12). Measurements are carried out with a shtikhmass by the electroacoustic method. An electric circuit consists of a power source (batteries for a flashlight), radio headphones, an equipment frame and a string. When the string is closed with a shtihmass, crackling is heard in the headphones. With a large length of the string, its sagging is taken into account.
From: Polyakov A.I.,  9976 views
Reconciliation aims to correct the location of various components in the equipment - mechanisms, parts. It is necessary that all these parts meet certain standards. There is a certain reconciliation algorithm. First of all, a reference geodetic network is created and control over it is carried out. Next, monitoring of the performance and shooting of the equipment under study together with the created network is carried out. This is necessary in order to identify whether the technique and its elements correspond to the geometric parameters. After the control is completed, geodetic documentation is compiled and schemes are developed.
In order for all measurements to be performed accurately and efficiently, they must be carried out with the appropriate equipment. Also, a lot depends on the qualifications of specialists performing geodetic reconciliation. To get the correct results, contact the Guild of Engineering. Here you will be fulfilled alignment of technological equipment both at the installation stage and during repair and dismantling of devices. The foundation for this equipment will also be analyzed for its correctness, strength and geometric compliance.
Geodesy is an accompanist of the installation and dismantling of equipment at industrial facilities. And do not underestimate geodetic surveys, as unprofessional alignment of technological equipment can further affect the implementation of the industrial process. Executive geodetic survey allows you to control the quality of work, as well as the condition of the equipment. Such a survey allows you to detect all deformations in time, as well as take all necessary measures to prevent them.
During the implementation of geodetic alignment, the following processes are carried out:
- work on the creation and control of the reference geodetic network;
- work aimed at monitoring the quality of work of technological equipment. The conformity control of the geometric parameters of the equipment, as well as its individual elements, is carried out;
- office work, which is carried out on the basis of the data obtained during the measurements. Such work includes the preparation and maintenance of executive documentation.
Surveyors of the company "Guild Engineering" when carrying out geodetic alignment of technological equipment, with the subsequent preparation of a report and recommendations for bringing it to the design position (turning and moving the support rollers in order to ensure the straightness of the furnace axis) use specialized equipment that allows you to obtain the most accurate data in short lines .
Ways to support equipment on the foundation
6.1. Installation of equipment on the foundation is carried out in the following way:
a) with alignment and fixing on permanent support elements and subsequent grouting of the gap "equipment - foundation" with a concrete mixture (Fig. 15, b);
b) with alignment on temporary support elements, grouting the gap "equipment - foundation" and with support when fixing the grout hardened material on the array (without lining, Fig. 15, a).
rice. 15. Support elements for alignment and installation of equipment
and ¾ temporary; b ¾ constant; 1 ¾ squeezing adjusting screws; 2 ¾ set nuts with Belleville springs; 3 ¾ inventory jacks; 4 ¾ lightweight metal pads; 5 ¾ packs of metal pads; 6 ¾ wedges; 7 ¾ support shoes; 8 ¾ rigid supports
With the first method of supporting equipment, the transfer of installation and operational loads to the foundation is carried out through permanent support elements, and the gravy has an auxiliary, protective or structural purpose.
If it is necessary to adjust the position of the equipment during operation, gravy may not be carried out, which should be provided for in the installation instructions.
6.2. When installing equipment using packages of flat metal pads, support shoes, etc. as permanent support elements. the ratio of the total contact area of the supports A with the foundation surface and the total cross-sectional area of the bolts A sa must be at least 15.
6.3. When the equipment is supported on a concrete grout, the operating loads from the equipment are transferred to the foundations directly through the grout.
6.4. The design of the joints is indicated in the installation drawings or in the installation instructions for the equipment.
In the absence of special instructions in the instructions of the equipment manufacturer or in the foundation project, the design of the joint and the type of supporting elements are assigned by the installation organization.
Equipment alignment
6.5. Alignment of equipment (installation in the design position relative to the specified axes and marks) is carried out in stages with the achievement of the specified accuracy indicators in terms of, and then in height and horizontality (verticality).
Deviations of the installed equipment from the nominal position should not exceed the tolerances specified in the factory technical documentation and in the installation instructions for individual types of equipment.
6.6. Alignment of equipment in height is carried out relative to working benchmarks or relative to previously installed equipment, with which the equipment being aligned is connected kinematically or technologically.
6.7. Alignment of the equipment in the plan (with pre-installed bolts) is carried out in two stages: first, the holes in the supporting parts of the equipment are aligned with the bolts (preliminary alignment), then the equipment is brought into the design position relative to the axes of the foundations or relative to the previously aligned equipment (final alignment).
6.8. The control of the position of the equipment during alignment is carried out both by conventional control and measuring instruments, and by the optical-geodesic method, as well as with the help of special centering and other devices that provide control of perpendicularity, parallelism and alignment.
6.9. Equipment alignment is carried out on temporary (alignment) or permanent (bearing) support elements.
As temporary (reconciliation) support elements when aligning the equipment before pouring it with a concrete mixture, the following are used: squeezing adjusting screws; adjusting nuts with disk washers; inventory jacks; lightweight metal linings, etc.
When reconciling, the following are used as permanent (bearing) supporting elements that also work during the operation of the equipment: packages of flat metal linings; metal wedges; support shoes; rigid supports (concrete pillows).
6.10. The choice of temporary (alignment) support elements and, accordingly, the alignment technology is made by the installation organization, depending on the weight of individual mounting blocks of equipment installed on the foundation, as well as based on economic indicators.
The number of support elements, as well as the number and location of the bolts tightened during alignment, are selected from the conditions for ensuring reliable fastening of the verified equipment for the period of its pouring.
6.11. The total area of \u200b\u200bsupporting the gully (alignment) supporting elements A, m 2 , on the foundation is determined from the expression
BUT£6 n А sa + G× 15×10 -5 , (21)
where n¾ the number of foundation bolts tightened when aligning the equipment; A sa ¾ calculated cross-sectional area of foundation bolts, m 2; G¾ weight of equipment to be verified, kN.
Total lifting capacity W, kN, temporary (alignment) support elements is determined by the ratio
W ³ 1.3 G + n A sa s 0 , (22)
where s0¾ preload stress of foundation bolts, kPa.
6.12. Temporary support elements should be located based on the convenience of equipment alignment, taking into account the exclusion of possible deformation of the body parts of the equipment from its own weight and the pre-tightening forces of the bolt nuts.
6.13. Permanent (bearing) support elements should be placed as far as possible close range from bolts. In this case, the supporting elements can be located both on one side and on both sides of the bolt.
6.14. Fixing the equipment in a verified position must be carried out by tightening the nuts of the bolts in accordance with the recommendations of Sec. 8 of this Guide.
6.15. The support surface of the equipment in the calibrated position must fit snugly against the support elements, the forcing adjusting screws ¾ to the support plates, and the permanent support elements ¾ to the foundation surface. The tightness of the mating metal parts should be checked with a 0.1 ml probe.
6.16. The technology for aligning equipment with the help of adjusting screws, inventory jacks, adjusting nuts, as well as on hard concrete pads and metal linings is given in App. 7.
Gravy Equipment
6.17. The pouring of equipment should be carried out with a concrete mixture, cement-sand or special mortars after preliminary (for joint structures on temporary supports) or after final (for joint structures on permanent supports) tightening of the bolt nuts.
6.18. The thickness of the gravy layer under the equipment is allowed within 50-80 mm. If there are stiffeners on the supporting surface of the equipment, the clearance is taken from the bottom of the ribs (Fig. 16).
Fig.16. Gravy scheme for equipment
1 ¾ foundation; 2 ¾ gravy; 3 ¾ supporting part of the equipment; 4 ¾ stiffening rib
6.19. The grout in the plan should protrude beyond the supporting surface of the equipment by at least 100 mm. At the same time, its height must be greater than the height of the main layer of grout under the equipment by at least 30 mm and not more than the thickness of the equipment support flange.
6.20. The gravy surface adjacent to the equipment must slope away from the equipment and be protected with an oil resistant coating.
6.21. The strength class of a long loaf or mortar when the equipment is supported directly on the grout should be taken one step higher than the foundation concrete class.
6.22. The surface of the foundations before grouting should be cleaned of foreign objects, oils and dust. Immediately before grouting, the surface of the foundation is moistened, while preventing the accumulation of water in the recesses and pits.
6.23. It is not allowed to grout under the equipment at an ambient temperature below 5°C without heating the mixture to be laid (electric heating, steaming, etc.).
6.24. The concrete mixture or mortar is fed through the holes in the base part or from one side of the poured equipment until the mixture or mortar reaches a level on the opposite side that is 30 mm higher than the height of the level of the supporting surface of the equipment.
The supply of the mixture or solution should be carried out without interruption. The level of the mixture or solution on the supply side must exceed the level of the poured surface by at least 100 mm.
For pouring equipment, you can use concrete pneumatic blowers of the S-862 type or concrete pumps of the SB-68 type.
6.25. The supply of concrete mixture or mortar is recommended to be carried out by vibrating using a storage tray. The vibrator should not touch the supporting parts of the equipment. With a width of the poured space of more than 1200 mm, the installation of a storage tray is mandatory (Fig. 17).
Rice. 17. Gravy equipment with a storage tray
1 ¾ formwork; 2 ¾ supporting part of the equipment; 3 ¾ storage tray; 4 ¾ vibrator; 5 ¾ gravy mixture; 6 ¾ foundation
The length of the tray should be equal to the length of the poured space.
It is not allowed to rest the tray on the pouring equipment.
The level of the concrete mixture when grouting with a tray should be approximately 300 mm above the supporting surface of the equipment and kept constant.
6.26. The surface of the gravy within three days after completion of work must be systematically moistened, sprinkled with sawdust or covered with burlap.
6.27. When using a concrete grout, the size of the coarse aggregate should be no more than 20 mm.
6.28. The selection of the concrete composition is carried out in accordance with the current normative documents. The draft of the concrete mix cone should be at least 6 cm. To improve the properties of the concrete of the gravy (reduce shrinkage, increase mobility), it is recommended to introduce the SDB additive in an amount of 0.2 - 0.3% of the mass of cement. With the introduction of SDB, the consumption of cement and water is approximately reduced by 8-10% while maintaining the calculated value of the water-cement ratio. Sand concrete can be used as a gravy.
6.29. To protect the grout from corrosion in aggressive environments, coatings should be used in accordance with the requirements of SNiP 2.03.11.
6.5. Alignment of equipment (installation in the design position relative to the specified axes and marks) is carried out in stages with the achievement of the specified accuracy indicators in terms of, and then in height and horizontality (verticality).
Deviations of the installed equipment from the nominal position should not exceed the tolerances specified in the factory technical documentation and in the installation instructions for individual types of equipment.
6.6. Alignment of equipment in height is carried out relative to working benchmarks or relative to previously installed equipment, with which the equipment being aligned is connected kinematically or technologically.
6.7. Alignment of the equipment in the plan (with pre-installed bolts) is carried out in two stages: first, the holes in the supporting parts of the equipment are aligned with the bolts (preliminary alignment), then the equipment is brought into the design position relative to the axes of the foundations or relative to the previously aligned equipment (final alignment).
6.8. The control of the position of the equipment during alignment is carried out both by conventional control and measuring instruments, and by the optical-geodesic method, as well as with the help of special centering and other devices that provide control of perpendicularity, parallelism and alignment.
6.9. Equipment alignment is carried out on temporary (alignment) or permanent (bearing) support elements.
As temporary (reconciliation) support elements when aligning the equipment before pouring it with a concrete mixture, the following are used: squeezing adjusting screws; adjusting nuts with disk washers; inventory jacks; lightweight metal linings, etc.
When reconciling, the following are used as permanent (bearing) supporting elements that also work during the operation of the equipment: packages of flat metal linings; metal wedges; support shoes; rigid supports (concrete pillows).
6.10. The choice of temporary (alignment) support elements and, accordingly, the alignment technology is made by the installation organization, depending on the weight of individual mounting blocks of equipment installed on the foundation, as well as based on economic indicators.
The number of support elements, as well as the number and location of the bolts tightened during alignment, are selected from the conditions for ensuring reliable fastening of the verified equipment for the period of its pouring.
6.11. The total area of \u200b\u200bsupporting the gully (alignment) supporting elements A, m 2 , on the foundation is determined from the expression
BUT£6 n А sa + G× 15×10 -5 , (21)
where n¾ the number of foundation bolts tightened when aligning the equipment; A sa ¾ calculated cross-sectional area of foundation bolts, m 2; G¾ weight of equipment to be verified, kN.
Total lifting capacity W, kN, temporary (alignment) support elements is determined by the ratio
W ³ 1.3 G + n A sa s 0 , (22)
where s0¾ preload stress of foundation bolts, kPa.
6.12. Temporary support elements should be located based on the convenience of equipment alignment, taking into account the exclusion of possible deformation of the body parts of the equipment from its own weight and the pre-tightening forces of the bolt nuts.
6.13. Permanent (bearing) supporting elements should be placed as close as possible to the bolts. In this case, the supporting elements can be located both on one side and on both sides of the bolt.
6.14. Fixing the equipment in a verified position must be carried out by tightening the nuts of the bolts in accordance with the recommendations of Sec. 8 of this Guide.
The basic parts of the machines are aligned separately in the vertical and horizontal planes by two methods:
Optical-geodesic;
According to geodesic signs.
Equipment alignment operations are the most responsible and are performed by highly qualified specialists.
The greatest accuracy of equipment alignment is provided by the optical-geodesic method.
3.1. Optical geodetic method
The alignment of the basic parts of the machines in height and horizontal is carried out using a level and a millimeter ruler (Fig. 3.1).
By determining the excess of the corresponding points of the base part (as a rule, located above the place where the machines are attached to the foundations), the accuracy of the installation is checked and the necessary adjustments are made according to one of the above methods of installing the equipment.
Alignment begins with setting the height of the lining package:,
where is the actual gap between the foundation and the design mark of the supporting surface of the base part;
The amount of elastic deformation of the package under load.
Then the base part is installed and the final alignment of the machine in height is carried out with pre-tightening of the bolts. It is not allowed to adjust the level of the horizontal plane of the base part by adjusting the tightening torque of the foundation bolts. This leads to additional stresses, which, together with the operating stresses, can exceed the tensile strength of the part.
In some cases, when checking horizontalness, it is advisable to use a laser fixed on the tube of the level. The spot from the light beam on the leveling ruler allows you to judge the position of the base part. This method is used to mount the rails of the sinter machine horizontally.
Alignment of parts in the horizontal plane is carried out with a theodolite (Fig. 3.2). Deviations from the longitudinal and transverse axes are controlled, as well as skew relative to these axes.
Fig.3.1. Definition of excesses:
HI - instrument horizon; b, d - readings along the ruler relative to the benchmark and the surface of the foot of the linings; h is the height of the control
marks; h f - the actual height of the foundation in place
lining installation
The longitudinal axis of the machine and the axis of the drive are marked on the base parts with risks or lines.
The main and auxiliary working axes, fixed on the foundation with dies, are implemented with a theodolite sighting beam.
Theodolite is set exactly above the core of the die. At the opposite end of the working axis, a luminous mark is installed above the core of the second plate and a crosshair of theodolite lines is fixed on it. If the axis of the machine is fixed with risks, then its deviation from the working axis is fixed by a theodolite, which is installed on a platform that has the ability to move in a horizontal plane with an indication of the amount of displacement.
Fig.3.2. Scheme for the alignment of plates by the optical-geodesic method:
1 - theodolite type T-2; 2 - portable sighting mark with a micrometric head; 3 - small-sized leveling rail; 4 - stationary luminous mark; 5 - die; 6 - plate; 7 - level of type HA-1;
8 - stand axis; 9 - auxiliary axle
The measurement of skew angles is carried out directly with a theodolite.
In this way, it is possible to carry out alignment in terms of assembled machines that have parts that determine the position of the axes of the machine (output shafts). In this case, next to the main working axis, an auxiliary one is broken, which is implemented by installing a theodolite and a luminous mark. According to the readings of magnetic leveling rulers installed on the cylindrical surfaces of the shafts, the deviations of the machine axis relative to the axis on the foundation are judged.
3.2. instrumental method
The scheme of reconciliation of basic details by geodetic signs is shown in fig. 3.3.
Fig.3.3. Scheme of reconciliation of basic details by geodetic signs
With the help of level 7 and straightedge 9, all points of the controlled surface are combined with a horizontal plane. The height coordinate is measured with a pin 10 between the calibration ruler 9 and the benchmark 11. The position of the base part in height is changed due to the thickness of the linings. In the horizontal plane, the basic parts are aligned along two axes. The longitudinal axis is fixed with string 6, the transverse axis - with string 3 relative to dies 12, 17. Strings of steel wire with a diameter of 0.3 - 0.5 mm rest on racks 8. Foundation reinforcement elements or special frames are used as racks. The stable position of the strings is achieved by weights 2. To eliminate vibrations of the weights in strong winds, they are placed in vessels with mineral oil. The strings are aligned on the dies 12 using plumb lines 1.
The deviation of the plumb lines 5 from the longitudinal and transverse axes fixed on the housing characterizes the accuracy of the installation of the equipment in the plan.
This method has a reduced accuracy in comparison with the first, and the presence of strings makes it difficult to carry out lifting and transport operations.
3.3. Shaft alignment
One of the types of equipment alignment is shaft alignment.
This, at first glance, a simple operation requires great care and simple, but very important calculations for the selection of linings and the amount of displacement in the horizontal plane (Fig. 3.4).
Shaft alignment is to eliminate their misalignment and distortions in the horizontal and vertical planes.
When aligning the shafts, the following operations must be performed:
Measurement of radial and end clearances in the vertical plane;
Determination by calculation based on the results of measurements of the required sizes of linings for the supports of the centered shaft;
Installation of pads under the supports;
Measurement of radial and end clearances in the horizontal plane;
Determination by calculation based on the results of measurements of the required displacement values of the supports of the centered shaft in the horizontal plane;
Displacement of the supports of the centered shaft in accordance with the calculated data;
Fixing a centered node;
Half coupling connection.
When measuring radial and end clearances, the coupling halves of the centered shafts must rotate together in order to eliminate surface defects of the coupling halves (dents, shells, etc.) and their eccentricity during manufacture or assembly.
Fig.3.4. Shaft alignment: a, b - radial and end displacement
coupling halves at measurement points 1, 3 and 2, 4, respectively; S is the value of shaft misalignment; d is the diameter of the circle on which the measurement point is located; - the angle of misalignment of the axes of the shafts
According to the results of measurements, the required amount of displacement in the vertical plane is determined (by changing the thickness of the linings under the supports a and b in the horizontal plane).
Radial clearances fix the misalignment of the shafts, end clearances - misalignment of the axes.
The amount of displacement in the horizontal plane for the support BUT (see fig. 3.4)
,
for support B
.
Amount of displacement in the vertical plane for the support A
,
for support B
,
where d is the diameter at which the gaps are measured.