CN103321883B - Actuating cylinder of reciprocating compressor gas flow regulating system - Google Patents
Actuating cylinder of reciprocating compressor gas flow regulating system Download PDFInfo
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- CN103321883B CN103321883B CN201310253664.4A CN201310253664A CN103321883B CN 103321883 B CN103321883 B CN 103321883B CN 201310253664 A CN201310253664 A CN 201310253664A CN 103321883 B CN103321883 B CN 103321883B
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Abstract
The invention relates to an actuating cylinder of a reciprocating compressor gas flow regulating system. The actuating cylinder is designed integrally and fixedly connected with an unloading pressure fork, and mainly comprises a cylinder body, a piston, a piston rod, an oil intake and return structure and attached connecting and fastening structures. The piston rod is fixedly connected with the unloading pressure fork through a flange so that disadvantages and repeating impacts caused by the split design are avoided effectively. By the aid of a fastening flange and double clamp nuts on the outer side of the cylinder body, mounting conditions of suction valves with different spring stiffness on site can be met, the proper distance between the lower end of the unloading pressure fork and a valve disc is guaranteed, and accordingly the valve disc of the suction valve can be ejected or retracted effectively through the gas flow regulating system. In addition, the structure and the working principle of the cylinder are creative, completely meet different application requirements of reciprocating compressor gas flow regulation on site, and can be applied to a total-travel suction valve opening process, a part-travel suction valve opening process and an intermittent total-travel suction valve opening regulation process. The actuating cylinder has low cost and high reliability.
Description
Technical field
The present invention relates to a kind of novel oil cylinder structure, be specially adapted to the actuator in the electrodeless amount regulating system of reciprocal compressor.
Background technique
Reciprocating compressor is a kind of large-scale dynamic equipment in flow industry enterprise extensive uses such as oil, refinery, Coal Chemical Industry, gas pipelines, due to its working stability, compression efficiency is high, pressure range is wide, and being widely used in the compressed medias such as hydrogen, rock gas, gas, propylene gas is micromolecular occasion.For an industrial reciprocating compressor, its rated discharge amount, when structural design, is determined according to design speed, piston area, piston movement stroke; But in actual production, because the change of rear end industrial production to gas demand causes that reciprocating compressor is actual is not always in oepration at full load; Due in chemical industry, oil refining production process, the change of technological process, the change of raw material type, and the change of the market demand all can require that the air displacement of reciprocating compressor can regulate in the larger context.
Apply more reciprocating compressor tolerance regulative mode in current production to comprise: start/stop machine adjustment, rotational speed regulation, pipeline adjustment, clearance volume adjustment, pressing-off suction valve regulate.Wherein, pressing-off suction valve regulating method is most widely used, and generally includes two kinds, one is total travel pressing-off suction valve in reciprocating compressor working cycle process, by controlling the multiple cylinder of reciprocating compressor, reaching and regulating tolerance object, realize tolerance and regulate, but regulation range and precision lower, can only 0% be reached, 25%, 50%, 75%, 100%; Another kind is partial journey pressing-off suction valve, the method presses off and closedown by controlling Aspirating valves in a reciprocating compressor work cycle, reach the object controlling air displacement to a certain extent, tolerance degree of regulation and scope exceed total travel pressing-off suction valve method.As patent US-A-5695325 is rotated between air valve and valve seat by specific device, realize Aspirating valves open and close; Patent EP-A-0893605 drives off-load fork pressing-off suction valve by electrohydraulic control technology; Formed the amount regulating system comprising Zhejiang University's machine Research Institute of product, the stepless amount regulating system of HydroCOM of Austrian He Erbige company research and development, has applied for Chinese patent CN03158561.2.
In above-mentioned tolerance regulating method, mostly adopt oil cylinder as actuator, existing cylinder structure form is split-type structural, and namely cylinder movement piston rod or unloader lever are pitched with execution off-load is split-type design, therefore easily brings die misalignment and Impact Problems repeatedly.Split type oil cylinder can be applicable in total travel pressing-off suction valve regulating method, because cylinder action frequency is lower, there will not be serious Impact Problems repeatedly; But for partial journey pressing-off suction valve, and intermittent total travel pressing-off suction valve regulating method has applied for Chinese patent 201310000611.1, and the type cylinder action effect will be had a greatly reduced quality, and often cause the generation of the faults such as valve block fracture.
Summary of the invention
The present invention is directed to existing reciprocating compressor amount regulating system cylinder structure defect, propose a kind of new reciprocating compressor amount regulating system and perform oil cylinder, it is characterized in that comprising following content:
1, this cylinder piston rod 11, off-load fork 32 adopt clamp flange A1 to be fastenedly connected, and effectively avoid die misalignment in conventional split-type design and Impact Problems repeatedly; Oil cylinder agent structure comprises cylinder body 26, the moving piston 14 in cylinder body, piston rod 11, the clamp flange B7 outside cylinder body and tightening nut A9, tightening nut B12;
2, the structure of cylinder body 26 comprises from top to bottom successively: the protective housing of piston rod upper end, retainer 21, upper end cap 20, upper oil-distributing plate 18, filler opening A17, filler opening B27, leakage of oil recovery port C31, casing wall 15, lower oil-distributing plate 10, leakage of oil plate 5, lower end cap 4;
Retainer 21 is threaded with protective housing, is pressed on upper end cap 20 by bolt A25 by retainer 21; Upper oil-distributing plate 18 has filler opening A17, filler opening B27, leakage of oil recovery port C31; Upper end cap 20 and upper oil-distributing plate 18 adopt bolt B 19 fastening; Upper oil-distributing plate 18, casing wall 15, lower oil-distributing plate 10, leakage of oil plate 5, lower end cap 4, is fixedly connected with from top to bottom between two, and seal ring 8 is installed at matching gap place between two;
Upper oil-distributing plate 18, be all processed with in-line A16 in casing wall 15 and lower oil-distributing plate 10, from up to down mutually through, be processed with in-line B28 in upper oil-distributing plate 18, in-line A16 is communicated with filler opening A17, and in-line B28 is communicated with filler opening B27;
Upper oil-distributing plate 18, casing wall 15, be all processed with leakage of oil pipeline R29 in lower oil-distributing plate 10 and leakage of oil plate 5, from up to down mutually through, leakage of oil pipeline R29 is communicated with by bend in upper oil-distributing plate 18 with leakage of oil recovery port C31;
3, clamp flange B7 is threaded with lower oil-distributing plate 10, tightening nut A9, and tightening nut B12 is threaded with casing wall 15; In oil cylinder installation process, clamp flange B7 and Aspirating valves valve gap 39 are bolted connection; Use tightening nut A9 and tightening nut B12, cylinder body 26 is locked with clamp flange B7, thus realizes being fastenedly connected of cylinder body 26, clamp flange B7 and Aspirating valves valve gap 39, prevent loosening; Aspirating valves valve gap 39 and compressor block 38 are fastened by bolts; Aspirating valves valve gap 39 central aperture, oil cylinder lower end cap 4 is provided with radial direction seal ring 30, when oil cylinder is installed on Aspirating valves valve gap 39, rely on the sealing of the high temperature and high pressure gas realized in compressor block that closely cooperates of radial direction seal ring 30 and Aspirating valves valve gap 39 intermediate hole;
4, the protective housing of piston rod upper end can adopt one of two kinds of mode of structure, one is outside thread protective housing 23, its external bottom end screw thread 35 and the mating reaction of the screw thread in upper end cap 20 center hole, use the blind hole in outside thread protective housing 23 piston 14 to be pressed onto the lower end surface 42 of oil cylinder inner cavity 40; Another kind is internal thread protective housing 33, and its inner bottom screw thread 34 and the mating reaction of the screw thread 24 of piston rod 11 upper end, extract the upper-end surface 41 of oil cylinder inner cavity 40 by piston 14; These two kinds of mounting types can be used for adapting to different in-site installation mode needs;
5, the clamp flange A1 of piston-rod lower end adopts with piston rod 11 and is threaded, fastening locking by pin for suppressing metal 2 and locking clip 3.
Cylinder piston rod can be pitched with off-load by adpting flange and be fixedly connected with by the present invention, thus realizes piston rod and directly drive off-load to pitch motion, ensures the reliability and stability that eject.
Accompanying drawing explanation
Fig. 1 is the structure sectional view of oil cylinder of the present invention;
Fig. 2 is the shape assumption diagram of oil cylinder of the present invention;
Fig. 3 is the protective housing that the present invention adopts external thread structure;
Fig. 4 is the protective housing that the present invention adopts female thread structure;
Fig. 5 is oil cylinder of the present invention and compressor valve gap scheme of installation;
Fig. 6 is the scheme of installation that oil cylinder of the present invention adopts external thread structure protective housing;
Fig. 7 is the scheme of installation that oil cylinder of the present invention adopts female thread structure protective housing;
Fig. 8 is that oil cylinder of the present invention completes and ejects test chart actuation time;
Fig. 9 is that oil cylinder of the present invention completes and recalls test chart actuation time.
Embodiment
Fig. 1 is the structure sectional view of oil cylinder of the present invention, 1 represent piston rod and off-load pitch between clamp flange A, 2 fastening screw trip bolts representing adpting flange, the 3 locking clips representing adpting flange, cylinder piston rod can be pitched with off-load by adpting flange and be fixedly connected with, thus realize piston rod and directly drive off-load to pitch motion, ensure the reliability and stability that eject.
4 represent lower end cap, are provided with radial direction seal ring 30 outside it, when can ensure that oil cylinder and Aspirating valves valve gap 39 assemble, leak without high temperature and high pressure gas; 5 represent leakage of oil plate, and inside is processed with draining pipeline, towards leakage of oil recovery port C31; 7 represent the clamp flange B outside cylinder body, 9 represent tightening nut A, 12 represent tightening nut B, clamp flange B7 is arranged on Aspirating valves valve gap 39 by bolt C6 is fastening, cylinder body 26 is fixed with clamp flange B7, thus is ensured the fastening installation of oil cylinder and Aspirating valves valve gap 39 by recycling tightening nut A, tightening nut B; The lower oil-distributing plate of 10 representatives, inside is processed with inflow pipeline, upwards leads to filler opening A17, and opposite side leads to piston lower portion, and high pressure oil can promote piston upwards, thus drives off-load fork 32 to recall, and no longer pressing-off suction valve valve block, ensures that compressor normally works; 14 represent piston, and 15 represent casing wall, are processed with inflow pipeline and drain line in casing wall, lead to filler opening A17 and leakage of oil recovery port C31 respectively; 17 represent filler opening A, 27 represents filler opening B, the upper oil-distributing plate, 20 of 18 representative represents upper end cap, 21 and represents the outside thread protective housing that retainer, 23 represents piston rod upper end, in-line A16 is processed with in upper oil-distributing plate, in-line B28, drain line R29, respectively with filler opening A17, filler opening B27, leakage of oil recovery port C31 are communicated with.All be fixedly connected with between each parts of oil cylinder, connect gap place and all adopt seal ring 8 to seal, prevent oil cylinder internal high pressure oil from leaking.
Fig. 2 is the shape assumption diagram of oil cylinder of the present invention, and 31 represent leakage of oil recovery port C, and 32 represent off-load fork.Drain line R29 in leakage of oil recovery port C31 and upper oil-distributing plate, not in same plane, is connected by bend.
Fig. 3 is that the outside thread protective housing 23,35 that the present invention adopts represents protective housing outside screw; Fig. 4 is that the internal thread protective housing 33,34 that the present invention adopts represents protective housing internal whorl.
Fig. 5 is oil cylinder of the present invention and compressor valve gap scheme of installation, and 36 represent Aspirating valves, and 37 represent Aspirating valves gland, and 38 represent compressor block, and 39 represent Aspirating valves valve gap.Through hole is had in Aspirating valves valve gap 39, oil cylinder lower end enters in compressor block by through hole, oil cylinder lower end cap is provided with radial direction seal ring 30, when oil cylinder is fastenedly connected by bolt Aspirating valves valve gap 39, rely on radial direction seal ring 30 and the sealing of the high temperature and high pressure gas realized in compressor block that closely cooperates of Aspirating valves valve gap 39 intermediate throughholes, prevent gas leak.
The oil cylinder installation of the present invention's design and working procedure, according to on-the-spot reciprocating compressor Aspirating valves spring rate size, can be divided into two kinds:
1 Aspirating valves spring rate is less, under vehicle stop state, oil cylinder inner carrier 14 is pressed onto bottom by outside thread protective housing 23, contact with oil cylinder internal cavities 40 bottom surface 42, as shown in Figure 6, now bolt A25 is utilized to be fixed on cylinder body retainer 21, ensure that piston position no longer changes, oil cylinder is installed on Aspirating valves valve gap 39, off-load fork 32 is relied on to be pressed off completely by Aspirating valves valve block, rotational fastener flange B7 is tight to the laminating of Aspirating valves valve gap 39 surface, utilize bolt C6 by clamp flange B7 and Aspirating valves valve gap 39 fastening, should be noted now tightening nut A9, tightening nut B12 and clamp flange B7 is in loosening state, unclamp retainer 21, take off outside thread protective housing 23, piston 14 and cylinder body 26 cannot synchronous axial system, at this moment manual rotation's cylinder bodies 26 to utilize the outer-hexagonal structure of piston rod 11 upper end to ensure, the particular location of 32 is pitched in adjustable cylinder body inner carrier 14 and off-load, after off-load fork 32 reaches specified position, by locked to tightening nut A9, tightening nut B12 and clamp flange B7, thus oil cylinder is secured entirely on Aspirating valves valve gap 39, at this moment, oil pipe is received filler opening A17 respectively, filler opening B27, promotion piston 14 moves by high pressure oil up or down, thus realizes pressing off and recalling action of off-load fork 32.
2 another kind of mounting types are: Aspirating valves spring rate is larger, under vehicle stop state, oil cylinder inner carrier 14 is pulled out topmost by internal thread protective housing 33, contact with oil cylinder internal cavities 40 upper bottom surface 41, as shown in Figure 7, under the effect of internal thread protective housing 33, piston rod 11, internal thread protective housing 33 are in tightening state with cylinder body; Oil cylinder is installed on Aspirating valves valve gap 39, now off-load fork 32 will contact completely with Aspirating valves valve block, but valve block is in buttoned-up status, rotational fastener flange B7 is tight to the laminating of Aspirating valves valve gap 39 surface, utilize bolt C6 by clamp flange B7 and Aspirating valves valve gap 39 fastening, should be noted that now tightening nut A9, tightening nut B12 and clamp flange B7 are in loosening state; Take off internal thread protective housing 33, piston 14 and cylinder body 26 cannot synchronous axial system, at this moment manual rotation's cylinder bodies 26 to utilize the outer-hexagonal structure of piston rod 11 upper end to ensure, the particular location of 32 is pitched in adjustable cylinder body inner carrier 14 and off-load; After off-load fork 32 reaches specified position, by locked to tightening nut A9, tightening nut B12 and clamp flange B7, thus oil cylinder is secured entirely on Aspirating valves valve gap 39; At this moment, oil pipe is received filler opening A17 respectively, filler opening B27, promotion piston 14 moves by high pressure oil up or down, thus realizes pressing off and recalling action of off-load fork 32.
The oil cylinder of the present invention's design can be used for the different tolerance regulating method of reciprocating compressor, comprises total travel pressing-off suction valve method, partial journey pressing-off suction valve method and intermittent total travel pressing-off suction valve regulating method.
Utilize related experiment equipment, test the cylinder action time of the present invention, test experiments equipment is as follows:
● Solenoid ball valve 1;
● the tolerance that execution architecture adopts this aspect to design regulates and performs oil cylinder, stroke 2.3mm, piston diameter 25mm;
● automatical control system is PLC S7-224XP CN and Omron solid-state relay G3TB-ODX03PM;
● test instrument is fluke portable oscilloscopel 190-62;
● supplementary equipment is L-type reciprocating compressor one;
The execution oil cylinder adopting the present invention to design in experiment is as the rear end actuator of Solenoid ball valve, and control signal adopts two kinds of control signals: PLC analog pulse signal, reciprocating compressor actual motion key phase signal.
1 experiment one
Experimental state: control signal is analogue signal, gathers lower column signal in experiment, in order to analyze the performance characteristic of oil cylinder.
● export the time lag T ejecting signal and start to oil cylinder to eject
1;
● eject T actuation time
2;
● eject action the shortest in electricity time T
3;
● export the time lag T recalling signal and start to oil cylinder to recall
4;
● recall T actuation time
5;
● recall action the shortest in electricity time T
6.
Table 1 PLC analog pulse signal is as input unit: ms
2 experiments two
Experimental state: drive compressor, control signal is actual key phase signal, gathers, in order to analyze the performance characteristic of oil cylinder in experiment to lower column signal.
● export the time lag T ejecting signal and start to oil cylinder to eject
1;
● eject T actuation time
2;
● eject action the shortest in electricity time T
3;
● export the time lag T recalling signal and start to oil cylinder to recall
4;
● recall T actuation time
5;
● recall action the shortest in electricity time T
6.
Table 2 PLC compressor key phase signal is as input unit: ms
Claims (1)
1. reciprocating compressor amount regulating system performs an oil cylinder, it is characterized in that:
1) this cylinder piston rod (11), off-load fork (32) adopt clamp flange A (1) to be fastenedly connected; Oil cylinder agent structure comprises cylinder body (26), moving piston (14) in cylinder body, piston rod (11), clamp flange B (7) outside cylinder body and tightening nut A (9), tightening nut B (12);
2) structure of cylinder body (26) comprises from top to bottom successively: the protective housing of piston rod upper end, retainer (21), upper end cap (20), upper oil-distributing plate (18), filler opening A (17), filler opening B (27), leakage of oil recovery port C (31), casing wall (15), lower oil-distributing plate (10), leakage of oil plate (5), lower end cap (4);
Retainer (21) is threaded with protective housing, is pressed on upper end cap (20) by bolt A (25) by retainer (21); Upper oil-distributing plate (18) has filler opening A (17), filler opening B (27), leakage of oil recovery port C (31); Upper end cap (20) and upper oil-distributing plate (18) adopt bolt B (19) fastening; Upper oil-distributing plate (18), casing wall (15), lower oil-distributing plate (10), leakage of oil plate (5), lower end cap (4), is fixedly connected with from top to bottom between two, and seal ring (8) is installed at matching gap place between two;
Upper oil-distributing plate (18), in-line A (16) is all processed with in casing wall (15) and lower oil-distributing plate (10), from up to down mutually through, in-line B (28) is processed with in upper oil-distributing plate (18), in-line A (16) is communicated with filler opening A (17), and in-line B (28) is communicated with filler opening B (27);
Upper oil-distributing plate (18), casing wall (15), leakage of oil pipeline R (29) is all processed with in lower oil-distributing plate (10) and leakage of oil plate (5), from up to down mutually through, leakage of oil pipeline R (29) is communicated with by bend in upper oil-distributing plate (18) with leakage of oil recovery port C (31);
3) clamp flange B (7) is threaded with lower oil-distributing plate (10), and tightening nut A (9), tightening nut B (12) are threaded with casing wall (15); In oil cylinder installation process, clamp flange B (7) and Aspirating valves valve gap (39) are bolted connection; Use tightening nut A (9) and tightening nut B (12), cylinder body (26) and clamp flange B (7) are locked, thus realizes cylinder body (26), being fastenedly connected of clamp flange B (7) and Aspirating valves valve gap (39); Aspirating valves valve gap (39) and compressor block (38) are fastened by bolts; Aspirating valves valve gap (39) central aperture, oil cylinder lower end cap (4) is provided with radial direction seal ring (30), when oil cylinder is installed on Aspirating valves valve gap (39), rely on the sealing of the high temperature and high pressure gas realized in compressor block that closely cooperates of radial direction seal ring (30) and Aspirating valves valve gap (39) intermediate hole;
4) protective housing of piston rod upper end adopts one of two kinds of mode of structure, one is outside thread protective housing (23), its external bottom end screw thread (35) and the mating reaction of the screw thread in upper end cap (20) center hole, make the blind hole in outside thread protective housing (23) piston (14) is pressed onto the lower end surface (42) of oil cylinder inner cavity (40); Another kind is internal thread protective housing (33), its inner bottom screw thread (34) and the mating reaction of the screw thread (24) of piston rod (11) upper end, extract the upper-end surface (41) of oil cylinder inner cavity (40) by piston (14);
5) the clamp flange A (1) of piston-rod lower end adopts with piston rod (11) and is threaded, fastening locking by pin for suppressing metal (2) and locking clip (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310253664.4A CN103321883B (en) | 2013-06-24 | 2013-06-24 | Actuating cylinder of reciprocating compressor gas flow regulating system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310253664.4A CN103321883B (en) | 2013-06-24 | 2013-06-24 | Actuating cylinder of reciprocating compressor gas flow regulating system |
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| CN103321883A CN103321883A (en) | 2013-09-25 |
| CN103321883B true CN103321883B (en) | 2015-07-15 |
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| CN201310253664.4A Active CN103321883B (en) | 2013-06-24 | 2013-06-24 | Actuating cylinder of reciprocating compressor gas flow regulating system |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107228068B (en) * | 2017-05-08 | 2018-11-16 | 北京化工大学 | A kind of reciprocating compressor exhaust amount adjustment method and device |
| CN108506272A (en) * | 2018-05-31 | 2018-09-07 | 广濑精密机械（太仓）有限公司 | One kind being followed by formula and clamps stroke adjustable hollow angling cylinder |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3518032A (en) * | 1968-05-24 | 1970-06-30 | Dresser Ind | Compressor cylinder unloader |
| JPS5596382A (en) * | 1979-01-17 | 1980-07-22 | Hitachi Ltd | Capacity regulator for reciprocal compressor |
| CN200975378Y (en) * | 2006-09-27 | 2007-11-14 | 济南新三思动态试验技术有限公司 | Servo straight-line actuator |
| CN201437802U (en) * | 2009-07-22 | 2010-04-14 | 宁波优耐特模具有限公司 | Hydraulic cylinder |
-
2013
- 2013-06-24 CN CN201310253664.4A patent/CN103321883B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3518032A (en) * | 1968-05-24 | 1970-06-30 | Dresser Ind | Compressor cylinder unloader |
| JPS5596382A (en) * | 1979-01-17 | 1980-07-22 | Hitachi Ltd | Capacity regulator for reciprocal compressor |
| CN200975378Y (en) * | 2006-09-27 | 2007-11-14 | 济南新三思动态试验技术有限公司 | Servo straight-line actuator |
| CN201437802U (en) * | 2009-07-22 | 2010-04-14 | 宁波优耐特模具有限公司 | Hydraulic cylinder |
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