Патент USA US3050321код для вставки
Aug. 21, 1962 3,050,311 W. L. MIKELL' SOLID RING FLOATING PACKING Filed Nov. 23, 1960 14 2 FIG. 1 2 16\ /15 _ BWlNBORNiIf/E ‘ELL 904" ‘pmr‘r ATTORNEY tile :4 nte ' Patented Aug. 21, 1962 2 3,950,311 SULID RHNG FLQATHNG PAOKING Winborn L. Mikeil, Houston, Tex., assignor to Garloek, Inc, Palmyra, N.Y., a corporation of New York Filed Nov. 23, 196i), Ser. No. 71,289 5 Claims. (Cl. 277—157) which are contained in a vessel located to the right of the packing box ‘from passing through the openings between the rod and the stu?ing box, there has been provided a set of packing rings, 3-5. 'Ihese packing rings, to be described hereinafter, have inner surfaces of su?‘icient diameter to pass over the piston rod 1. The rings are assembled in an annular recess or channel formed at the The invention relates to mechanical packings, and par ticularly mechanical packings for sealing parts under going relative motion in environments of high ?uid pressures. In many industries, there exists a need for rigid ele ments such as packing rings for inclusion in the wall of left hand side of the stu?ing box. The gland 7 is pro vided for holding the rings in the channel formed in the stu?ing box. The gland is secured to the stuffing box by means such as bolts 8. Normally, ?uid escaping through the opening between the piston rod 1 and the stu?ing box 2 acts along the front wall 9 of the stu?ing box tending to drive the set of packing rings 3—6 axially a container bearing ?uids, such as liquid or gas, and de signed to prevent or minimize leakage between the rigid 15 against the gland 7. Additionally, some ?uid escaping parts of such a- container. Where the rigid parts of a along the rod or shaft tends to drive the packing rings radially outward. Normally, this radial outward force container are capable of relative motion, the packing is required to be in sliding contact with one or more parts tends to break the sealing action sought by use of packing of the container. Examples of such moving parts are rings. ' piston rods, valve stems, plungers, moving shafts, etc. The ?oating metal packings now in common usage, trap ?uid pressure in the ocean of the stuffing box partially As ?uid pressures are increased, greater demands are placed on the packing to insure intimate sealing contact occupied by the spring part 14, which is between the with the moving parts. Prior art packing devices have outside diameter of the packing rings and the inside di proved to be essentially ineffective with respect to wear ameter of the stu?ing box. This ?uid pressure commonly at pressures above 15,000 pounds per square inch. In 25 creates great and excessive forces, which force the seg general, excessive heating due to friction is developed mental parts of common pacldng rings into the surface at the points of intimate contact with consequent destruc or’ the rod, thereby generating excessive friction resulting tion of the packing, thereby necessitating high packing in heat and wear. In my invention, however, a partial replacement costs, increased down time of equipment to balance of the forces created by the ?uid in the area of permit packing replacement, etc. 14 is obtained by the forces created by the ?uids in the It is therefore an object of this invention to provide an area 13, thereby greatly reducing the net resulting forces improved mechanical packing ‘for sealing parts under which act to force the inside surface of the packing ring . going relative motion. contact with the outer surface of the rod, thus the friction It is another object of this invention to provide an im between these two parts is'greatly reduced along with proved mechanical packing capable of operating at higher pressures. It is a further object of this invention to provide an the resultant heat and wear. In accordance with oneernbodiment of the present invention, use is made of this normally undesirable radial improved mechanical packing capable of e?ectively seal outward force to provide an improved packing ring. Re ing under conditions of variable pressure. ferring to FIG. 3, there is shown in exaggerated form one It is another object of this invention to provide an im 40 of the four rings, for example ring 3. Ring 3 has an proved packing which automatically adjusts to varying inner circumference large enough to permit passage of sealing requirements. the ring 3 over the circular shaft 1. As shown in PEG. 3, While the novel and distinctive features of the inven the channel 19 which is formed in the packing box 2, to tion are particularly pointed out in the appended claims, accommodate the ring, is of a larger diameter than the a more expository treatment of the invention, in principle 45 outer diameter of the ring 3. In the embodiment of FIG. and in detail, together with additional objects and ad 3, the outer circumference of the ring 3 is shown to have vantages thereof, is atforded by the following description a uniform dimension, that is, it is circular. However, the and accompanying drawings in which: inner surface of each ring has a ?rst radius over a given In FIG. 1 illustrates in longitudinal section form, a sec tion of a packing box embodying my arrangement for chord angle equal to the radius of the piston rod 1. Over the remaining chord angle A the inner surface of the ring has a radius which is larger than the radius of rod 1. Thus there exists essentially a crescent shaped opening 13 between the rod and the inner surface 12 of mechanical packings; In FIG. 2 illustrates schematically the manner in which the various packing rings of a packing set are designed to intimately contact the moving rod or piston; FIG. 3 is an exaggerated view of one of the packing the ring 3. A spring 14 of, for example, stainless steel, forces the inner ‘surface of the ring 3 defined by the chord FIG. 4 illustrates essentially, in exploded view form, angle 0 into intimate pressure sealing contact with the abutting surface of the piston rod 1. Under these the manner in which the various rings are located on the conditions, any leakage ?uid passing axially along the moving rod or shaft; FIG. 5 illustrates an arrangement for holding the rings under spring pressure against the rod or shaft, this ar rod 1 through the crescent'shaped opening 13 causes a force shown as F to be developed. This force F is in rings; rangement being here shown as a ?at portion; the direction which effectively forces the portion of the inner surface of ring 3 de?ned by the chord angle 6 into pressure sealing contact with the abutting portion of the FIG. 6 illustrates another view of FIG. 5; and piston rod surface, this being accomplished by the force FIG. 7 illustrates the arrangement illustrated in FIG. 65 F applying pressure against that portion of the inner sur 5 positioned to be used to hold the rings against the rod face of ring 3 de?ned by the chord angle A to separate it or shaft. Referring to FIG. 1, there is shown in longitudinal from rod 1. .It is seen, therefore, .thatthe spring 11%- has the primary function of establishing the initial intimate section, a packing box having an arrangement of pack ing rings, embodying the present invention. 70 contact between the inner surface of ring 3v de?ned by the The piston rod 1 passes through an opening in the chord angle 0 into intimate contact with the abutting packing box 2.. To prevent ?uids under high pressures surface of the piston rod 1, but that thereafter force F 3,050,311 A I‘! , 3 ' 5; , developed by the leakage ?uid maintains this intimate contact. said rod completely encircle the circumference of said It is this force, developed at high pressures, ' which results in the improved sealing action permitted by the present invention. The force F as previously de- . scribed could never result in forces as great as those forces utilized in popular current designs of ?oating metal pack ing, wherein the total ?uid pressure in position designated ‘by number 10 is utilized for force segmental rings against rods. The 'Working surface of-the rings should conform as accurately as possible to that of the sliding member of rod 1, or should achieve this condition within a reason able time after the sealedmembers have startedto oper- ' ate. Furthermore, the ring should be composed of ma terial that will not damage the sliding member during the process of wearing into a ?tting condition and should be capable of withstanding without injury the heat re sulting from packing friction. The material of the pack? the rod. The present invention balances the total forces in position 10, due to the rings 3—6 being constructed of materials of su?icient mechanical strength to adequately resist those forces tending to collapse the ring radially in ing ring should also be free of contamination or attack ward toward the rod. by the ?uid being packed, and should be su?iciently rigid ’ It is obvious that the use of a single ring as shown in so that it does not- seize the piston rod 1 during opera ~ FIG. 3 is insu?icient to provide sealing action completely 15 tion but permits sliding contact with minimum friction. around the surface of, the rod 1. Accordingly, a plurality The rings of the present invention can and will be made of any of the materials of construction currently being utilized for the manufacture of ?oating metal packings or of the present invention employing a series of four rings. ?oating mechanical packings. Such materials would in In order to simplify the explanation, FIG. 2 only illus 20 clude ferrous metal, non ferrous metals, plastics and trates the positioning of the inner surface or inner diame modi?ed plastics. The near substitution of a newior ter of the respective rings 3-6 with respect to piston rod previously’ unused material'or combination of materials 1. Each of the inner surfaces is shown having a portion of construction should not be considered as an improve de?ned by a chord angle which has a radius substan ment on the principles of the present invention, for it is tially equal to the radius of the piston rod 1. There 25 the intent of the inventor to utilize any or all existing maining portion of each inner surface is shown to have known materials or new material, if such materials should a radius somewhat larger than the radius of the rod 1. offer improved wear properties, strength, heat'resistance, Use is made of heavy lining to indicate the relative loca or other properties that would render it suitable for use tions of the portions of such inner surfaces that have a in the present invention. radius equal to the radius of the piston rod. In the ar For purposes of illustration, a solid packing ring and a rangement of FIG. 2 and reading from left to right, the reciprocating shaft Were shown. It should be understood equal radius portions are shown to occur at zero degrees, that the principles of this invention are also applicable to ' 180 degrees, 90 degrees, and 270 degrees. If the heavy split packing rings, piston rings, and rotating shafts. lining portions are superimposed over one another in While the principles of theinvention have now been the axial direction of piston rod 1, it is seen that they 03 U1. made clear,- there will be immediately obvious to those ‘overlap and completely cover’ the circumference of the skilled in the art many modi?cations in structure, ar-‘ ' of rings are employed. ' Returning to Fl G. 2, there is shown one embodiment piston rod. Thus, any leakage of ?uid passing axially rangement, proportions, elements, and components used along ‘the piston rod drives the inner surfaces of the suc cessive rings so that the set of packing rings provides an in the practice of the invention, and otherwise, which are particularly adapted for speci?c environmentsrand oper» intimate sealing action completely surrounding the cir 40 ating requirements, without departing from those princi cumference of the piston rod. The result is a mechanical ples. The appended claims are therefore intended to packing which responds to leakage ?uid pressure to pro videa very satisfactory sealing-action, even under ex cover and embrace any such modi?cations within the limits of the true spirit and scope of the invention. tremely high pressures. . It is‘ understood that the two circles above-mentioned, which comprise the inner surface of any one of the re ' spective rings 3-6 and which have been described as hav ing differing radii, are joined together by arcs to form an irregular circular shape with a smoothly rounded cir cumference. Referring to FIG. 4, there is shown in exploded form the several mechanical packing rings 3-6 having inner surfaces oriented and additionally positioned by respec It is claimed: . " _ 1. A mechanical packing set adapted to respond to ?uid pressure for sealing said packing set to a rod of circular cross-section comprising‘ a plurality of rings, each of said rings having an inner surface of sufficient ' size to pass said rod, said inner surface of each ring hav ing a ?rst radius over a given chord angle equal to the radius of said rod, and a second radius over the remain ing chord angle which is larger than said rod radius, said, rings being mounted on said rod in pressure seal abutting relationship and angularly oriented about said rod so that resulting from leakage ?uid pressure passing through the 55 said inner surfaces of said ?rst radius completely encircle effectively crescent shaped opening take over and main the circumference of said rod, said rings when so mount tainthe sealing contact necessary to minimize leakage of ed having their inner surfaces of said second radius ' ?uid beyond the packing set. adapted to respond to ?uid pressure developed between tive springs 14 to intimately contact the rod 1 until forces While FIG. 4 illustrates one form of spring construc said second radius inner faces and the adjoining rod'sur- , tion, it is obvious that other forms may be resorted to 60 faces to force said inner surfaces of ?rst radius into pres without departing from the spirit of the present inven tion. For example, FIG. 5 illustrates an arrangement in which the rings are notched for the springs. This at‘ rangement eliminates the need for keying each of the rings 3—6 and the need for separately attaching the springs. Furthermore, whereas the invention has been described as involving the use of four springs, it is obvious that a different number of rings, either more or less, could be employed to affect the desired sealing action under differ ent operating requirements. It is only sul?cient that the rings bepmounted on the rod in pressure sealed abutting relationship and angularly oriented about the rod so that the portions of the inner surfaces of the rings which have sure 'seal contact with said rod. ' . 2. ‘A mechanical packing set adapted to respond t ?uid pressure for sealing said packing set to a moving part comprising a plurality of solid discs, each of said discs having a completely enclosed inner opening of mill cient size to pass said part, the inner opening of each disc having a ?rst portion of its periphery dimensioned to conform substantially exactly to a corresponding por-' tion of the periphery of said part and said inner opening of each disc having a second portion of its periphery. di mensioned to be substantially larger than the correspond ing remaining periphery of said part, said discs being mounted on said part in pressure seal abutting relation ship and angularly oriented about said part so that said a radius over a given chord angle equal to the radius of 75 ?rst portions of said discs completely surround said part, 3,050,311 5 6 said discs when so mounted having their inner surfaces said rod so that said portions of said inner surfaces over lap one another and thereby surround the circumference corresponding to said second portions adapted to respond of said rod, said rings, when so mounted, adapted to respond to ?uid pressure developed between said larger faces and the adjoining part surfaces to force said inner surfaces corresponding to said ?rst portions into pressure 5 radial inner ‘surfaces and the adjoining rod surfaces to force said portions of said inner surfaces into pressure seal contact with said part. seal contact with said rod. 3. A mechanical packing set adapted to respond to 5. A mechanical packing set adapted to respond to ?uid pressure for sealing said packing set to a moving ?uid pressure for sealing said packing set to a moving rod rod of circular cross-section comprising four solid rings, each of said rings having inner opening surfaces of sul? 10 of circular cross-section comprising four solid rings, each of said rings having inner opening surfaces of sui?cient cient size to pass said rod, a ‘continuous portion of the radii to pass said rod, a continuous portion of the pe periphery of said inner surface of each ring having a riphery of said inner surface of each ring having a ?rst ?rst radius substantially equal to the radius of said rod radius substantially equal to the radius of said rod, and a and a radius over the remaining periphery which is larger than said rod radius, said rings being mounted on said 15 radius over the remaining periphery which is larger than said rod radius, said rings being mounted on said rod in rod in pressure seal abutting relationship and angularly pressure seal abutting relationship and angularly oriented oriented about said rod so that the bisectors of the periph about said rod so that the bisectors of the peripheral inner eral inner surfaces having said ?rst radius occur sub surfaces having said ?rst radius occur substantially at stantially at zero degree, 90 degree, 180 degree, and 270 degree points around the circumference of said rod, said 20 Zero degree, 90 degree, 180 degree, and 270 degree points around the circumference of said rod, spring means act rings, when so mounted, adapted to respond to ?uid pres ing on each of said rings for biasing said peripheral irmer sure developed between said larger radial inner surfaces surfaces having said ?rst radius into intimate cont-act with and the adjoining rod surfaces to force said peripheral the adjoining rod surfaces, said rings when so mounted inner surfaces having said ?rst radius into pressure seal 25 adapted to respond to ?uid pressure developed between contact with said rod. said larger radial inner surfaces and the adjoining rod 4. A mechanical packing set adapted to respond to surfaces to maintain said peripheral inner surfaces having ?uid pressure for sealing packing set to a moving rod of said ?rst radius in pressure seal contact with said rod. circular cross-section comprising four solid rings, each of to ?uid pressure developed between said last named sur said rings having inner opening surfaces of su?icient radii to pass said rod, a continuous portion of the periphery of 30 said inner surface of each ring having a ?rst radius sub stantially equal to the radius of said rod and a radius over the remaining periphery which is larger than said rod radius, said rings ‘being mounted on said rod in pressure References Cited in the ?le of this patent UNITED STATES PATENTS 1,831,674 1,891,436 seal abutting relationship and angularly oriented about 35 2,172,141 Lindgren ____________ __ Nov. 10, 1931 Mitchell _____________ __ Dec. 20, 1932 King ________________ __ Sept. 5, 1939.