JPH0341294B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates generally to reciprocating pumps, and more specifically, to the art of reciprocating pumps, and more particularly, to the art of reciprocating pumps that can be mounted on side rods (drive rods) without inducing torsion in the external (top) crosshead of the reciprocating pump during installation. This invention relates to a side rod tension device for tightening.

For reciprocating pumps of the inverted plunger type with a closed plunger that reciprocates in conjunction with the side rod, whether vertical or horizontal, nuts are used to secure the external (or upper) crosshead to the side rod. Tightening created a torsional moment about the center point of the nut, which caused serious maintenance problems in that the coupled external crosshead could bend one or the other of the side rods out of their normal position. This problem,
This is due to the frictional resistance generated when the contact surface of the nut engages the external crosshead.

When this development occurs, during operation of the reciprocating pump, the load generated by the pressure of the fluid discharged during the discharge stroke tends to straighten the bent side rod. This development then applies a lateral load to the plunger, creating friction within the packing box. As a result, the plungers and their gaskets and pushers of such reciprocating pumps experience excessive wear, eventually requiring replacement or repair of these parts.

In addition, the angular displacement of the external crosshead reduces the operating gap of the removable telescoping mechanism, which causes parts to rub against each other, resulting in wear, and also causes metal particles to fall into the crankcase, causing this inversion. Damage to the bearings and seals used in the drive device of plunger type reciprocating pumps.

One prior art approach to solving this problem is to use a large, cumbersome, and expensive torque wrench to tighten the nut while the external crosshead is held in place with another wrench. However, this method has been limited to reducing the degree of angular displacement of the external crosshead. It has been difficult to use such a wrench on large upright pumps because the external crosshead is located high and cannot be reached without a scaffolding platform. Even with such a wrench, this method was not accurate and left some twist in the external crosshead.

The present invention seeks to solve this problem and, therefore, it is an object of the present invention to facilitate accurate tensioning of the side rods of a closed plunger reciprocating pump to create twist in the external crosshead. The purpose is to apply a predetermined level of stress to the side rod without any stress.

Another object of the invention is to provide a tensioning device that is capable of evenly distributing force to at least two side rods.

A further object of the invention is a tensioning device that facilitates tensioning at least two side rods of a closed plunger type reciprocating pump to a predetermined stress value, eliminating the need for large and inconvenient torque wrenches. It is an object of the present invention to provide an even distribution of forces between the side rods, the external crosshead, and the threaded connection that holds the external crosshead mounted on the side rods.

According to the present invention, this object is achieved in a reciprocating pump which is provided with a horizontal member connected to a plurality of reciprocating side rods by screw fastening means and is driven reciprocatingly via the horizontal member. an extending portion formed on the outer side of the threaded fastening means of each side rod; b. fixed and variablely held on each of the extending portions, with at least one surface thereof facing the outer surface of the horizontal member; (c) a jack holding means for removably holding the jack part at a predetermined mounting position on each extension part of the side rod; e) supplying a working fluid to cause the protrusion means to protrude, applying a predetermined force to the horizontal member and applying a tensile force to the side rod to a predetermined level, so that the horizontal member an external pressure means that enables the screw fastening means to be tightened with the jack portion attached without causing any twisting; This is achieved by means of a reciprocating pump side rod tensioning device which is characterized by the application of a uniform initial stress to the horizontal members.

In the tension device described above, the projecting means includes, for example, a hydraulic cylinder and a piston inserted into the hydraulic cylinder. The external pressurizing means also includes a hydraulic pump for applying force to the piston via a working fluid within the cylinder, and a measuring means for detecting the pressure. Note that a pressure plate may be interposed between the jack part and the horizontal member.

The present invention will be described in detail below based on the accompanying drawings.

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention;
Fig. 2 is a partial sectional view thereof, Fig. 3 is a plan view of the tension device and an explanatory diagram showing the hydraulic mechanism, Fig. 4 is an enlarged partially sectional side view of the tension device, and Fig. 5 is the same as Fig. 4. FIG.

1 and 2 show a closed plunger type upright triple reciprocating pump 10.
has a power section 11 and a liquid section 12.

The power unit 11 has a crankcase 13 in which a drive crankshaft 14 is rotatably provided. The crankshaft 14 has a connecting rod 14
a and an internal crosshead 15 via crosshead pin 14b. Spaced apart side rods (drive rods) 16, 17 are connected at one end to the crosshead 15 and extend from the power section 11 through the liquid section 12 to the outside of the pump where they connect the internal (lower) crosshead. The end remote from 15 is connected to the external (upper) crosshead 1 via suitable threaded nuts or fastening members 19, 20.
8.

In the illustrated closed or reversible plunger pump, the plunger 21 is connected to an external (internal) crosshead 18. The plunger 21
is slidably arranged in a cylinder 22, which is made as liquid-tight as possible by means of a suitable gasket 23.

In operation, when the crankshaft 14 is rotated by some suitable means (not shown), the crosshead 15 will be raised or lowered.
The motion is transmitted via side rods 16, 17 and crosshead 18 to plunger 21, causing it to reciprocate within cylinder 22.
The structure and operation described above will be known to those skilled in the art and do not constitute the present invention, and therefore will not be described in further detail.

In order to prevent the power unit 11 from getting dirty, the side rods 16 and 17 are each provided with a protective cover 24 at its upper end.
It has 25.

The above-mentioned type of reciprocating pump has a capacity of 3000 GPM.
(gallons per minute: 113551/m) maximum
40000PSIG (pounds per square inch, gauge:
It operates at a pressure of 2812.4Kg/cm ² ). At the pressures and capacities at which such reciprocating pumps operate, it is important that all parts are in proper alignment, otherwise the pump may become inoperable or remain in operation. The pump will need to be repaired. As mentioned above, this is the position (alignment) of the side rod when assembling the external crosshead onto the side rod.
This is a problem.

In order to properly align or position the side rods and the external (upper) crosshead and to prevent twisting of the external crosshead as the fastening nuts 19, 20 are tightened during assembly, a tensioning device 30 according to the present invention is shown. This will be explained below.

This tension device 30 is attached to the side rod 1.
6 and 17 are removably attached to a predetermined number of pairs of side rods 16 and 17 so as to engage the outer surface of external crosshead 18, respectively.

As shown in FIGS. 1 and 2, the side rods 16, 17 each have first screwing means 31, 32 spaced apart from each end by a predetermined distance, and second screwing means 31, 32 at each end. Means 33 and 34 are provided, respectively. As a result, the external crosshead 18 is placed transversely on these side rods. Said nut 19,2
0 is screwed with the first screwing means 31 and 32, and these form the screwing and fastening means of the present invention. Initially, the nuts 19 and 20 are not tightened and the external crosshead 18 is loosely connected. Leave it in the assembled state. The tensioning device 30 also connects to the external crosshead 18.
are horizontally mounted on the extensions 35, 36 of the side rods via a second set of threaded nuts 37, 38 parallel to the outer surface of the rod. This second set of nuts 37 and 38 are
As clearly shown in FIGS. 2 and 4, respectively,
The end portions 35, 36 of the side rods 16, 17 are screwed together with the second screwing means 33, 34, forming the jack retaining means of the present invention.

The tension device 30 has a jack section 40 and a pressure plate 41. This jack part 40 has openings or holes 4 arranged at appropriate intervals as guiding means.
2, 43 are formed, and side rods 16,
The tension device 30 is mounted on the extension parts 35 and 36 of 17.
, so that the pressure plate 41 is disposed between the jack portion 40 and the outer or upper surface of the external crosshead 18.

The jack portion 40 and pressure plate 41 will be made of a suitable special steel to support the load due to hydraulic pressure.

A positioning pin 44 is fixed to the pressure plate 41 and fitted into the positioning hole 45 of the jack part 40, so that the jack part 40 can be fixed without disturbing the relative position between the jack part 40 and the pressure plate 41 during operation of the tension device. can be separated from the pressure plate 41.

Furthermore, the tension device 30 is attached to the side rod 16,
While maintaining the integrity of the tension device when attached to or detached from the extensions 35 and 36 of 17,
As will be described later, a fastener 46 is provided so that the jack portion 40 can be separated from the pressure plate 41 when the tension device is operated.

The fastener 46 includes a long hollow sleeve 47, which is fitted into a counterbore hole 48 formed in the pressure plate around the threaded hole 49, and passes through the positioning hole 50 to the outer surface of the jack portion 40. Extends to. A long threaded connecting pin 51 is arranged to pass through the sleeve 47, and its threaded end 52 is threaded into the threaded hole 49 in the pressure plate 41, and the annular shoulder is formed near the outer end surface of the jack portion 40. 53 holds the sleeve 47 in the assembled state, and the annular shoulder portion 53 has the jack portion 40 attached to the pressure plate 4 by the aforementioned positioning pin 44.
This prevents it from coming loose from the positioning state in which it is in contact with 1. A lifting ring 54 is provided at the outer end of the connecting pin 51, and when in use, the tension device 30 can be lifted up from the extensions 35, 3 of the side rods 16, 17 as required.
6 and detachable. All of the above is shown in FIGS. 1, 2 and 4.

3 to 5 show at least two cylinders 5 arranged at intervals in this jack part 40.
5 and 56 are provided, and piston members 57 and 58 are fitted therein, respectively.
These cylinders 55, 56 and piston member 57,
58 forms the protruding means of the present invention.

The external pressurizing means of the present invention is a hydraulic pump 64 described later.
and a meter 66 as a measuring means.

The cylinders 55, 56 communicate through openings 59, 60 with a common working fluid manifold 61 having a port 62 with an opposite end connected to a hydraulic pump. It is connected to a pipe 63 which is connected to a pipe 64. As a result, when the pump handle 65 is operated, hydraulic fluid flows from the hydraulic pump mechanism 64 through the tube 63, the port 62, the common manifold 61 and the openings 59, 60 into the cylinders 55, 56 to operate the pistons. let A gauge 66 is provided to determine the pressure applied to the pistons 57, 58 via the working fluid. The pistons 57, 58 are provided with suitable seals 67 so that the tension device 30
Uniform pressure is applied to the pistons 57 and 58 during operation.

Next, the operation of this embodiment will be explained.

In operation, the tension device 30 is attached to the lifting ring 5.
4, the lower surface (inner surface) of the pressure plate 41
are aligned and locked onto the extensions 35, 36 of the side rods 16, 17 so as to rest on the outer or upper surface of the external crosshead 18. Natsu 1
9 and 20 must not be tightened. Next, the nuts 37, 38 are screwed onto the threaded ends 33, 34;
Tighten by hand so that the tensioning device 30 is in tight contact with the outer or upper surface of the external crosshead 18.

Next, when the handle 65 is operated, the pressure indicated by the gauge 66 reaches a predetermined value and the side rod 1
Hydraulic pressure is applied via the fluid to the pistons 57, 58 until it provides the necessary tension on the pistons 6,17. As a result, the jacking part 40 and the pressure plate 4
1 and are separated from each other as shown by broken lines in FIG. The nuts 19, 20 are thus tightened to the external crosshead 18 with a simple manual wrench without inducing any twisting or distortion.

If the working fluid is then released, the nut 37,
38 and gripping the holding ring 54, the tension device 30 is attached to the side rod 1.
It can be removed from the extension parts 35 and 36 of 6 and 17.

Those skilled in the art will appreciate that since the working fluid is pumped uniformly into each cylinder 55, 56, the tension force will be uniformly applied to the side rods 16,17. Thus, a relatively simple device is provided to pre-stress the side rods and the cooperating external crosshead 18 to a predetermined level to connect them and provide proper operation for the reversing plunger 21 of the reciprocating pump 10. It is.

The present invention is not limited to the configuration shown in the drawings, but can be modified in various ways within the scope of rights defined in the claims.

The present invention, constructed as described above, is a removable, hydraulically operated tensioning device which uniformly applies tensile force to each side rod and provides a predetermined tension to the side rods without transmitting twisting force or distortion to the external crosshead. The nuts can be uniformly tightened to a level of 0.05 to provide a uniform tightening of the nuts to prevent twisting of the external crosshead connected to each side rod when the hydraulically operated tensioning device is removed. Also, since the force distributed to the two side rods is equalized, it is possible to load these side rods very precisely to the desired stress value, and there is no chance of them breaking due to fatigue. can.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view of a closed plunger type reciprocating pump showing the cooperative relationship between one plunger and one set of side rods, Fig. 2 is a partial cross-sectional side view of Fig. 1, and Fig. 3 is Fig. 2. FIG. 4 is a partially sectional enlarged side view of the tension device shown in FIG. 1, and FIG. 5 is a plan view taken along the line -- in FIG. 4. DESCRIPTION OF SYMBOLS 10... Reciprocating pump, 16, 17... Side rod, 18... External crosshead as a horizontal member, 21... Plunger, 30... Tension device, 40... Jack part, 41... Pressure plate, 4
2, 43... Hole as a guide means, 46... Fastener, 55, 56... Cylinder, 57, 58... Piston, 64... Hydraulic pump, 66... Instrument.

Claims (1)

[Scope of Claims] 1. A reciprocating pump comprising a horizontal member connected to a plurality of reciprocating side rods by screw fastening means and driven reciprocally via the horizontal member, comprising: a. Each of the side rods (b) a jack held in a variable fixed position on each of the above-mentioned extension parts, and at least one surface of which faces the outer surface of the horizontal member; c) a jack holding means for removably holding the jack at a predetermined mounting position on each extension of the side rod; e. supplying a working fluid to cause the protruding means to protrude, applying a predetermined force to the horizontal member and applying a tensile force to the side rod to a predetermined level, thereby twisting the horizontal member; an external pressure means that enables the tightening of the screw fastening means with the jack part attached without causing a A side rod tension device for a reciprocating pump characterized by applying uniform initial stress to the installed parts. 2. The side rod tension device for a reciprocating pump according to claim 1, wherein the jack part has a pressure plate between it and the outer surface of the horizontal member. 3. The protruding means provided on the jack part includes at least two hydraulic cylinders and the abutment surfaces that are slidably fitted into each of these cylinders and abut against the outer surface of the horizontal member. Claim 1 comprising a piston arranged to protrude from the
Side rod tension device for reciprocating pumps as described in Section 1. 4. The external pressurizing means comprises: a) a hydraulic pump connected to supply working fluid to at least two of the hydraulic cylinders to accurately and uniformly operate the piston; and b) pressurized by a discharge fluid. 4. A side rod tensioning device for a reciprocating pump as claimed in claim 3, further comprising: measuring means provided on said hydraulic pump for determining the pressure exerted thereon. 5. The jack part includes a pressure plate disposed between the outer surface of the horizontal member, and the protrusion means has at least two
Claim 1, characterized in that the device comprises two cylinders and a piston that is slidably fitted into each of the cylinders and is arranged to protrude from the abutment surface toward the pressure plate. side rod tension device for reciprocating pumps.