Swallow of 1 introductive 　 changes company refinery 100Y modelOil pump, the sealed structure between gland of former bearing box and runner shaft is labyrinthian and sealed, be in labyrinthian and sealed adscititious one dustproof annulus, sealed performance is poorer. Because the rotate speed of pump is higher, below the action of centrifugal force, the lube edge axis inside bearing box is swung from upright lid piece, leakage oily phenomenon is very common, cause bearing box, shaft coupling and week exclosure face to be stained with smeary, bring hidden trouble to safe production, create needless lube waste at the same time, polluted manufacturing environment badly again, those who affect civilized production and business amount to mark to upgrade. If operator cannot discover in time, cause the damage of machine pump likely still. Accordingly, improve composition of former oil seal, develop the structure of new-style oil seal that admirable, service life grows a kind of sealed performance to seal dispute in order to replace crude oil constant necessary.
The problem opportunity pump that 2 original sealed structures exist moves in because oil level is restricted, in oily pool of immerge of nut lower end, have lube mix, the surface inside edge gland drips below, direct drop arrives on runner shaft coming back, oil is accumulated on the axis a lot of, axis be gyralled is driven, oily edge axis is creeping, enter gland and shaft labyrinthian and sealed clearance, because labyrinthian and sealed gap is bigger, and sealed obstruction is lesser, once oil is hit hard into enchanted palace, swing outside ceaseless edge axis consequently piece, in the axis upright place is formed accumulate oil, make labyrinthian do not have sealed effect with dustproof annulus, produce leakage oil namely. The main problem that from above the analysis can see structure of former oil seal exists is bearing locknut too big mix labyrinthian and sealed gap is too big cases be less than significant sealed action. The 3 argumentation that improve plan and tentative selection 　 are new-style structure of the oil that prevent leakage should satisfy the following requirement: Want to assure to combine airtight sex of the part above all. In the meantime, structure simple, production maintenance uses compact, system convenient, finished product cheap, job is reliable, service life is long. Be aimed at the main reason of leakage oil, should from the following two respects proceed with undertakes improvement, prevent leakage oil. (1) , reduce locknut of bearing of 　 of the quantity that swing oil oiled deepness (the opposite distance of fluid face and locknut) it is a when affect size of the quantity that swing oil main factor. Reduce nut diameter, can reduce oiled deepness, reduce agitate oil, reduce the oily amount that falls to the axis thereby, reduce leakage oil to measure secondhand. (2) , improve 　 of structure of former oil seal to be analysed to its structure, tell from sealed principle angle can consider ram or block, space, derivative or infuse and flow resistance, be defeated instead, and the method such as these program combination. Be opposite above all space, can take machine sealed. Will look according to mechanical and sealed function, suitable scope, life, mechanical and sealed can applicable, but mechanical and sealed price is high, the structure is complex, what need a space bigger, tear open outfit inconvenience, unwell at structure of this kind of little space. Consider to use next derivative or infuse method, can achieve sealed requirement, but need assists device, the structure is complex, also cannot take consequently. Again the consideration uses the method of ram and block, as a result of the life with longer requirement, a few contacts sealed wait to wear away with axial contact like felt circle, ring washer, sealing ring, oil seal, life is finite, do not suit high speed to grow periodic movement, and easy happening hold an axis in the arms, eliminate consequently. Final consideration uses flow resistance or be defeated instead, or adopt comprehensive plan. Flow resistance is to use clearance of weather strip stricture or labyrinthian way to cause the fluid resistance that sealed place needs. Be defeated instead is to use weather strip to be caused to leak fluid press instead, made part is balanced or balance completely, lose the fluid advanced position instead, in order to achieve sealed goal. Its characteristic is inorganic instrument attrition, the structure is compact. The fluid is defeated instead (also weigh dynamic pressure) include labyrinthian helix sealed, move helix is sealed, sealed etc. Narrow, life grows consideration space, power comsumption small, structure is simple, disassemble convenient, price is low requirement, use flow resistance or be defeated instead reach its comprehensive plan is optimum. Be in flow resistance or in losing program instead, helix is sealed can satisfy afore-mentioned requirements integratedly most, because this is preferential consideration helix is sealed. In view of centrifugal and sealed but as sealed as other cooperate to use, to assure close result, helix of make choice of is sealed with form of centrifugal and sealed combination. If pursue - 1 shows: The 4 designs to 100Y pump calculate: According to theoretical analysis, helix is sealed its are in helix angle α the power when 6 ′ of 5 ° is the least, and same length is taken when 39 ′ of 15 ° sealed pressure is the greatest, combine a few data to give out practical experience, sealed pressure, power uses up give attention to two or morethings reach structural length, leave certain and safe abundant to spend, the design is as follows: [1] , [the design of sealed parameter calculates 4.1 helix of 2] 　 　 　 　 (1) , helix angle α to 100Y pump, the axis carries a diameter to be D=65mm, shaft part is extended to be able to use helix outside sealed length L0=56.5mm, its axis end and shaft coupling connect, leave 7mm interval, reason takes sealed length L=39.5mm. Because length and diameter are lesser, by sealed pressure formula (see from the back) [1] , sealed pressure is lesser, what reason helix angle chooses is bigger, take ° of the =5 that it is α 49 ′ . So the =0.1019 of α of tangential value T=tan of α (this value by from the back computation reachs) . (2) , relative to groove wide U takes U=0.5~1.0 commonly, here U=a/(a B)=0.75. (3) , relative to groove deep υ takes υ =2~10 commonly, take the =(c H)/c=5 that it is υ . (4) , sealed clearance C recommends C=(0.6~2.6)/10000m to take C=0.26mm, as a result of have before helix is sealed centrifugal and sealed, can assure sealed function, taking large space is to because machining error reachs mounting error,prevent, produce clash with the axis. (5) , groovy deep H, h by formulary H=c ＊ (υ - 1) gets: H=0.26 ＊ (5-1)=1.04, take for H=1.0mm. (6) , the head counts I, the head counts I by in front the counts by screw head choice principle of place discussion: High rotate speed (N>5000r/min) , pick only head; Low rotate speed (N<5000rmin) chooses bull. As a result of this pump N=2950r/min, recommend according to concerning a material, take I=4. (7) , helix lead S, take S=16 (take full facilitating treatment) ; Criterion by α of Tan of ＊ of S= π D, 49 ′ of α =5 ° . (8) , helix chamfer wide A, facewidth B gets α of Tan of ＊ of D of ＊ of A= π U by formula / I=3.00mm b= π ＊ (α of Tan of ＊ of 1-u) ＊ D / I=1.0mm 　 　 (9) , axial horn fast ω and helix are circumferential the computation of speed V: 　 of 　 of N/60=7.6m/s of π of N/60=308.9rad/s v= of ω =2 π (10) , helix chooses length to be L=39.5mm 　 　 by the structure (11) , helix is sealed ′ of pressure Δ P, tu(1-u)(υ of 　 of 　 of 　 of 　 of 　 of 　 of 　 of W D LCp/c2 [1] of ω of =r of Δ P ′ - 1)(υ 3-1) among them: Cp=-----------------------------------(υ of 3 T2u(1-u)(of 1 T2) υ 3-1)2 U=0.75, t=0.1019, υ =5.0 generation enters: Cp=0.178, press Cp=0.178, rare oil-lubricated take viscosity coefficient to slant 9.8Pa/s of small μ =0.00223 × , ω =308.9rad/s, d=0.065m, l=0.0395m, c=2.6 × 10-4
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