CN213017244U - Hydraulic connection structure of piston compressor - Google Patents

Abstract

The utility model discloses a piston compressor's hydraulic pressure connection structure, including crosshead body, thrust ring. The thrust ring sets up in the cross head is internal, and thrust ring one side butt has the wrong ring of twisting, twists ring one side butt and has the pressure body, it is provided with fastening nut to twist the ring outside, twist and wear to be equipped with the piston rod in ring and the pressure body, be provided with the seal ring groove in the pressure body, it is connected with the pressure piston to slide in the seal ring groove. The utility model discloses following beneficial effect has: the hydraulic connection structure of the piston compressor can solve the problem of rubber aging.

Description

Hydraulic connection structure of piston compressor

Technical Field

The utility model relates to a hydraulic pressure connection structure, in particular to piston compressor's hydraulic pressure connection structure.

Background

In the field of large compressors, dead center clearances belong to factors which must be considered in design, and the dead center clearance of a piston is the clearance between two end faces of the piston and the front and rear end faces of a cylinder body under the states of the maximum stroke and the minimum stroke of the piston in the cylinder body in the 360-degree operation process of a crankshaft. The gap near the end of the crankcase is a rear dead center, and the far end is a front dead center.

When the dead point clearance of the piston is adjusted, the adjusting ring basically fits on the crosshead body and keeps an ideal dead point clearance, which is called as a theoretical state. However, the dimensions of the parts in the ideal state do not have any deviation, and the actual production cannot be realized.

The hydraulic connection structure of the crosshead body and the piston rod in the prior art comprises the crosshead body, wherein a thrust ring is arranged in the crosshead body, and one side of the thrust ring is connected with a screwing ring. The screwed ring is internally abutted with a piston rod, an adjusting ring is arranged between the screwed ring and the piston rod, and the adjusting ring is abutted with the crosshead body. Aiming at the hydraulic connection structure in the prior art, in the actual production, the following practical problems are found:

1. when the size processing length of the piston rod is smaller than 5mm (which belongs to common errors in the field of large compressors), in order to ensure the correctness of a dead point gap, the screwed ring deviates 5mm to the outer side of the crosshead so as to ensure the normal operation of a hydraulic connection structure of the compressor;

2. when the axial cumulative size of the middle body, the connecting cylinder and the cylinder seat or the main parts thereof is out of tolerance after being machined, and the axial cumulative size is reduced by 5mm for example, in order to ensure the length of the dead point gap, the screwed ring needs to be screwed into the inner side of the crosshead from an ideal state, and at the moment, the adjusting ring on the screwed ring collides with the crosshead body. The adjusting ring can not be screwed in at the moment, and the adjusting ring is usually disassembled and then screwed in;

3. even when the dead point clearance of the piston is adjusted to an ideal state during installation, the adjusting ring is basically close to the crosshead body, and the ideal state is not reasonable in practical production application. The reason is as follows: according to the section in the standard document GB/T1804-2000 tolerance of linear and angular dimensions without tolerance,

as shown in the table above, if the length sizes of the middle body and the connecting cylinder are calculated according to the standard of more than or equal to 1000, the sum of the medium m-level tolerance between the two parts is +/-2.4 mm, the value belongs to the non-out-of-tolerance value in the standard state, the parts are completely qualified in manufacturing, and if the errors are calculated according to the limit value of the lower deviation, the adjusting ring collides with the crosshead body during installation. The collision is more severe in the out-of-tolerance case. Under the upper deviation state, the dead point clearance is in an ideal state when the two parts are installed.

In the prior art, after long-time use, the inner sealing ring can be aged. In summary, the main problem of the present application is how to solve the problem of rubber aging in the prior art.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a piston compressor's hydraulic pressure connection structure. The hydraulic connection structure of the piston compressor can solve the problem of rubber aging.

The invention aims to be realized by the following technical scheme:

a hydraulic connection structure of a piston compressor comprises a crosshead body and a thrust ring. The thrust ring is arranged in the crosshead body, one side of the thrust ring is connected with a screwing ring in an abutting mode, one side of the screwing ring is connected with a pressure body in an abutting mode, a fastening nut is arranged on the outer side of the screwing ring, a plurality of unloading grooves are formed in the middle of the elastic rod, and the unloading grooves are grooves.

The unloading groove is of a bullnose structure.

The radius of the circular bead of the unloading groove is 2-5 mm.

The utility model discloses following beneficial effect has: the hydraulic connection structure of the piston compressor can solve the problem of rubber aging.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment;

FIG. 2 is a schematic structural view of a further modification of the embodiment;

fig. 3 is a schematic structural diagram of the snap spring.

Reference numerals: 1. a crosshead body; 2. a thrust ring; 3. screwing in the ring; 4. a pressure body; 5. A piston rod; 6. fastening a nut; 7. hand hole; 8. an O-shaped sealing ring; 9. a Y-shaped seal ring; 10. sealing the ring groove; 11. a ring groove; 12. a clamp spring; 13. a tolerance gap; 14. unloading the trough; 15. a pressure piston; 16. and (5) pressing the hole.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications to the present embodiment without inventive contribution as required after reading the present specification, but all of them are protected by patent laws within the scope of the claims of the present invention.

As shown in fig. 1, a hydraulic connection structure of a piston compressor includes a crosshead body 1 and a thrust ring 2. Wherein, thrust ring 2 sets up in crosshead body 1, and thrust ring 2 one side butt has screwed ring 3. The pressure body 4 is abutted on one side of the screw-in ring 3. A piston rod 5 is arranged in the screwing ring 3 and the pressure body 4 in a penetrating way. The fastening nut 6 is arranged outside the screw-in ring 3.

Utility model as follows:

1. to the two-way regulation problem, the utility model discloses be provided with hand hole 7 on twisting ring 3. Compared with the prior art, the utility model discloses cancelled adjustable ring and screw, shifted its function to twist on the ring 3. A tolerance gap 13 is arranged between the screw-in ring 3 and the crosshead body 1, and the length of the tolerance gap 13 is 10 mm. A certain distance is arranged between the screwing ring 3 and the crosshead body 1, so that when the part has lower deviation, the screwing ring 3 can be adjusted in position to adapt to the out-of-tolerance problem of the part.

For the length of 10mm, the maximum sum of the tolerances in the prior art cannot exceed 10mm, and if the sum exceeds 10mm, the part needs to be scrapped. The length is preferably 10 mm.

Secondly, integrate the adjustable ring with the screw and twist on ring 3 for twist ring 3 need not to assemble the installation with the adjustable ring, directly utilize hand hole 7 screw in locating pin can, the installation is simple and convenient.

Through the improvement, hydraulic pressure connection structure has possessed two-way regulatory function for even size out-of-tolerance, the utility model discloses also can utilize out-of-tolerance part, reduce the disability rate of part.

Optimally, a reserved space is arranged between the screwing ring 3 and the pressure body 4, the width of the reserved space is 0.5-1mm, the reserved space is mainly used for adjusting the pressing position conveniently, the air compressor can be used for air compressors of different specifications, and meanwhile, certain spaces are reserved on two sides, so that the bidirectional adjusting function is realized.

2. After the modification, a new problem is found in actual production, namely that the mounting and the dismounting sometimes have the problem of being incapable of being pressed or not being pressed.

In practical use, the cylindrical pin is inconvenient to mount and dismount and is designed only for preventing the piston from moving in the transportation process. The pressure of suppressing when former installation is 150MPa, and actually often be less than this numerical value, get rid of behind the ageing class of material problem of rubber, to this problem, the utility model discloses an improvement point as follows:

and a Y-shaped sealing ring 9 is arranged in the pressure body 4. The Y-shaped sealing ring 9 solves the sealing problem when being pressed, so that the problem that the pressing cannot be carried out is basically solved. However, in order to solve the problem that the compressor can be pressed to 120MPa only during maintenance and disassembly, regular maintenance is difficult.

In order to solve the above problem, the pressure body 4 of the present invention is provided with a sealing ring groove 10. In which a Y-ring 9 is arranged. The utility model discloses modify its diameter to seal ring groove 10 and be used for reducing and suppress pressure: as shown in the following table

TABLE 1 data sheet of influence factors of sealing ring groove-pressing pressure

As can be seen from the above table, the pressing pressure can be reduced to 90MPa by changing only the diameter of the seal ring groove 10 without changing the outer diameter of the fastening nut 6. To this end, the following conclusions are drawn:

in actual use, only change the shape of sealing washer, can't solve and suppress the pressure and keep at high pressure level constantly, and through increasing the diameter of seal ring groove 10, can make and suppress pressure reduction, under the condition that suppresses pressure reduction, make required pressure accord with actual need completely, solve the unable dismantlement problem that the pressure was pressed in the time of the periodic maintenance.

Through the two improvements, the problem of bidirectional adjustment is solved, the problem of no pressing caused by bidirectional adjustment is solved, the two parts supplement each other, and the combination of the two parts is creative.

3. In the actual production work, new problems still arise in solving the above problems,

the thrust ring 2 is in a two-half annular structure, is fixed by an extension spring and is screwed and installed in the crosshead body 1. The original thrust collar 2 is assembled as follows:

the whole process is carried out by at least two persons, wherein one worker puts the thrust collar 2 into the connecting structure and holds the thrust collar by hands, and the other worker puts the hooks at two ends of the extension spring on the thrust collar 2 and then starts to screw the extension spring into the crosshead body 1 for installation. During the dismantlement, beat and unscrew fastening nut 6, back out the crosshead body 1 with hydraulic connection structure, the thrust ring 2 is pried into the opening to instrument such as reuse iron rod or screwdriver to prop up the spring with the iron rod, then lift thrust ring 2 off, unpack the spring hanger again at last, the installation is accomplished by two people with dismantling, and is comparatively inconvenient. When facing a large compressor, the thrust ring 2 has a 'mouth opening' phenomenon because the piston force is generally not lower than 40 tons. It is difficult to make the thrust ring 2 "mouth closed" by relying solely on the tension of the extension spring. It is common practice for those skilled in the art to increase the tension spring preload and decrease the length of the tension spring, but this is inconvenient for installation and removal and is easily harmful to the operator. When the piston force exceeds 80 tons, an extension spring needs to be added, so that the installation and the disassembly are more inconvenient.

In order to solve the problems, annular grooves 11 are arranged on two sides of the thrust ring 2, and clamp springs 12 are clamped in the annular grooves. The clamp spring 12 is structurally shown in the figure, the clamp spring is made of a 3-4mm steel wire, made of 65Mn, designed into an opening structure with an angle of 120 degrees, and the rest is closed. Practice proves that the improved installation process is simplified and can be operated by a single person, and the specific operation process is as follows:

a single operator holds the thrust collar 2 with one hand and holds the clamp spring 12 with the other hand to align the ring groove 11 for installation. When the anti-slip ring is disassembled, one clamp spring 12 is held by two hands, the clamp springs 12 in the aligning ring groove 11 are pushed, the clamp springs 12 in the ring groove 11 are popped out, and the anti-slip ring 2 is held by two hands, so that the anti-slip ring 2 is disassembled. The operation links are reduced, the labor is saved, the time is saved, and the efficiency is improved.

Chinese patent No. CN105971853B, in which a snap spring 12 with a hook is provided, completely solves the above problems. However, the non-hook clamp spring 12 proposed in this document provides versatility in the installation process. Firstly, jump ring 12 structure is comparatively simple, and the preparation is convenient, and secondly this jump ring 12 need not to match the compressor of various different specifications, and the suitability is better. And, the jump ring 12 of taking the hook is because both ends are sharp-pointed for produce the harm to the human body easily when carrying, consequently, the utility model discloses a jump ring 12 has the effect of conveniently carrying. In addition, compared with the snap spring 12 with the hook, the cost of the snap spring 12 is further reduced, and the market demand is met.

4. As shown in fig. 2, the piston rod 5 of the present invention is an elastic rod. The elastic rod support body is provided with a discharge groove 14 in the middle. The relief slots 14 are typically grooves. The relief groove 14 can reduce stress concentration between the elastic rod and the support body. Due to the arrangement of the unloading groove 14, the elastic rod is difficult to machine on a lathe, the effect is poor, and the surface roughness is proved to be up to Ra1.6 mu m. The abrasive cloth is utilized for polishing, the first is poor effect, the surface roughness is still higher than Ra0.8 mu m, and the second is time-consuming, labor-consuming and inconvenient.

In order to solve the above problem, the utility model provides a piston rod 5 is last to set up uninstallation groove 14, and uninstallation groove 14 adopts the bullnose structure. The results of comparing the sizes of the bullnose structures and the stress thereof with the grooves after UG stress element stress analysis are shown in the following table:

TABLE 2 stress comparison of groove structures to bullnose structures

The limiting conditions are as follows: the distance between the originally designed grooves is 4 mm. The wall thickness of the bullnose structure is 10 mm.

The diameter of the elastic rod, the diameter of the support body, the pressing pretightening force and the fillet radius of the groove prove that the space for changing the groove structure into the external fillet structure is enough, and the feasibility is achieved.

From the above table, the following conclusions are drawn:

(1) when the maximum stress values at the groove structure and the bullnose structure are substantially the same, the bullnose radius value is also smaller.

(2) The maximum stress at the round corner has a direct relation with the radius of the round corner, the size of the round corner is increased, and the maximum stress is reduced.

The stress contrast of the utility model after the size of the external end fillet is changed is shown as follows,

TABLE 3 stress comparison after change of outer end fillet size of elastic rod

The following conclusions are drawn from the above table: fillet size is inversely proportional to maximum stress.

Also widely used bullnose structure among the prior art, however, the utility model provides a bullnose structure's size is bigger, and its maximum stress is lower. And, because the size becomes bigger, the process of turning is more convenient. Further, the surface roughness is less than or equal to Ra0.4mm. And secondly, the radius of the external fillet is increased, so that the maximum stress at the fillet is averagely reduced by 10 percent, and the fatigue life of the fillet is prolonged.

The document, page 81, describes that the fatigue strength is improved by more than 10% and the fatigue life is prolonged by more than 100 times. Although the material of the elastic rod is not a high-strength material, the analogy can be made: the effect of the heat treatment was the same, the surface roughness value of the elastic bar was reduced from ra0.8mm to ra0.4mm, and if the fatigue strength was improved by 1%, the improvement in fatigue life by 5 times or more was no problem.

If the thickness of the support body is more than 15mm, the stress of the transition fillet structure exceeds that of the groove structure, and the good effect brought by the improvement is partially weakened. Therefore, the present document designs the optimum fillet radius size in the prior art, so that the effect thereof is optimized.

5. As shown in fig. 2 and 3, in order to solve the problem of aging of the inner seal ring, the utility model discloses utilize the pressure piston 15 to replace the Y-shaped seal ring 9 for suppressing. The pressure piston 15 is provided with an O-ring seal 8. Through this mode of suppressing, directly suppress in suppressing hole 16 for the piston impels to with twist the ring 3 butt of twisting, makes internal pressure can stably keep at better level, suppresses effectually.

In summary, the following steps:

the utility model provides a two-way regulation problem, further reduced the pressure of suppressing on the basis of the problem that the new construction produced simultaneously for the pressure of suppressing is in lower level and can realizes the installation maintenance. Meanwhile, the clamp spring 12 structure of the thrust ring 2 is designed, so that the universal and cost-reducing effects are achieved. Moreover, on the basis that the unloading groove 14 in the prior art is a groove, the service life is prolonged while turning is conveniently carried out to reduce the surface roughness by utilizing the excircle corner structure.

Claims (2)

1. The utility model provides a piston compressor's hydraulic connection structure, includes crosshead body, thrust collar, the thrust collar sets up in the crosshead body, and thrust collar one side butt has the wrong ring of twisting, twists ring one side butt and has the pressure body, twist the ring outside and be provided with fastening nut, twist and wear to be equipped with piston rod, characterized by in ring and the pressure body: a sealing ring groove is arranged in the pressure body, and a pressure piston is connected in the sealing ring groove in a sliding mode.

2. The hydraulic connection structure of a piston compressor as claimed in claim 1, wherein: an O-shaped sealing ring is arranged outside the pressure piston.

Images