HYDRAULIC BEARING PULLER

Transcription

1 HYDRAULIC BEARING PULLER Parag Ambre 1, Akash Muppid 2, Prf. Nitin Mre 3, Anil Birajdar 4, Sandip Barathe 4 1,2,4,5 BE Mechanical, Dr. D.Y. Patil Schl f Engineering, Pune. 3 Faculty, Dr. D.Y. Patil Schl f Engineering, Pune. ABSTRACT Nw a day s hydraulic system plays very imprtant rle in almst all the applicatin. As in autmbile industries, small service center, aircraft industries and ther departments where precisin is required. This review fcuses n study and develpment f cncept design f Hydraulic based bearing remver. Traditinal methd f bearing remval r installatin is hammering, but unnecessary hammering causes several prblems. The unsafe and excessive hammering cause s damaging f bearing surface r smetimes chances f failure and excessive human effrt is required. While the cnventinal Hydraulic puller using pump are cstly, huge, and high at maintenance. In rder t remve bearing safely, we have t design new methd by eliminating huge Hydraulic Pumps, reducing size f Cylinder, and prduce large amunt f frce by applying minimum effrt. The new design shuld be easy fr remval f bearing r gear frm the shaft. The hydraulic bearing puller is based n hydraulic system n the principle f Pascal s law which states that pressure change ccurring anywhere in a cnfined incmpressible fluid is transmitted thrughut the fluid such that the same change ccurs everywhere. In this paper we have studied varius existing methds fr bearing remval, cnsisting f Mechanical Jack Screw Puller, Hydraulic bearing remver using Pump, Hydraulic bearing puller and pusher using hydraulic jack. Keywrds: bearing remver, hydraulic bearing puller, hydraulic jack, mechanical puller, Pascal's law. I INTRODUCTION Bearings are used t reduce frictin between rtating shaft and supprt. Bearings have a finite perating life, it requires peridic replacement and rutine maintenance t prevent failure. Several factrs impact the service life f a bearing r the frequency fr required maintenance. Fr example, bearing lads, perating temperature, expsure t external envirnments, cntaminatin, lubricatin and even electrical currents acting n the bearing may impact a bearing's service life r the frequency that maintenance must be cnducted. The hydraulic bearing puller is a device which is used fr remving bearing frm the shaft. In the machine the press fit peratins are very cmplicated t align the assembly. Fr this type f peratins, we require heavy frce fr disassembly f the bearing frm the machines. It can be used widely & effectively fr remving the bearing. Bearings are made t exact tlerances and have very fine surface finishes. In rder t maintain the gemetrical precisin, the surface integrity f ball, rller bearing raceways and rlling elements, it is mandatry Page N:433

2 that care in strage, handling and installatin shuld be bserved. The hydraulic bearing puller perfrm pulling peratin f bearing safely and withut damaging the bearing surface. II DEFINITION OF PROBLEM Often times it is difficult t replace r service bearings due t the lcatin, size, weight, methd f cupling r type f bearing. A bearing, fr example, may weigh several hundred punds and/r be cupled t a part r shaft thrugh an interference fit. As a result, it is ftentimes necessary t remve the rtr r shaft assembly in its entirety t replace r repair the bearings. In sme instances, the entire machine must be transprted t a maintenance facility t replace the bearings. Hwever, it is desirable t replace bearings withut (i) Requiring remval f the rtr assembly r rtr shaft (ii) Transprting the machine t a maintenance facility. Traditinally, bearing remval dne by hammering, but such hammering causes several prblems. They are: Excessive hammering causes damage f bearing surfaces and smetimes chance t failure. Mre effrt required t remve bearing because f hammering. Damage t the shaft edges due t wear frm Jack Screw f mechanical pullers. Cnventinal hydraulic puller is nt prtable Increase in number f valves Requires spring return mechanism Pssibility f Leakage Length f cylinder increases Maintenance cst is high III. OBJECTIVE In rder t remve bearing safely we need t make mdificatin in traditinal methd. The mdificatin t be made shuld allw easy remval f bearing. The purpse f mdificatin is, Simplicity f peratin Remval f bearing dne withut damaging bearing surface. Cmpact, prtable and well suited. Lw cst. Skilled as well as unskilled persnnel can perfrm the peratin. Increasing the life f bearing. Page N:434

3 a) Pullers: IV. HEADINGS Designed as a tl t make the remval and installatin f bearings simple and efficient, bearing pullers ften resemble a pair f scissrs. In sme cases, the cnfiguratin f the puller will allw the extractin f bth gears and bearings, including thse that are cnnected with a series f shafts within the mechanism. Different sizes f bearing pullers make it pssible t use the device n everything frm a pair f skates t cmplicated industrial machinery. [iv] b) Hydraulic Jack: Hydraulic Jack is perhaps ne f the best examples f fluid pwer system. It plays very imprtant rle in autmbile industries t facilitate servicing and repair. It may be prtable device. By perating handle f small device and individual can lift lad f several tns. Hydraulic jack wrks n the principle f Pascal's law. Hydraulic Jack cnsists f Cylinder, Plunger, and Handle, Oil reservir, Pressure release and relief valve. When the handle is perated, the plunger reciprcates then the il frm the reservir is sucked int the plunger cylinder during upward strke f the plunger thrugh the suctin valve. The il in the plunger cylinder is delivered int the ram cylinder during the dwnward strke f the plunger thrugh the delivery valve. This pressurized il lifts the lad up, which is placed n tp plate f the ram. After the wrk is cmpleted the pressure in the ram cylinder is released by unscrewing the lwering screw thus the pressure releases and the ram is lwered, then the il is rushed int the reservir. [ii] V. INDENTATIONS AND EQUATIONS a. Hydraulics: The wrd hydraulics cncerned with study f behavir f water at rest and at mtin i.e. behavir f liquids. Hydraulics includes prperties, advantages and applicatins f liquids. The tw main scientists give the directin t frward, ne is Daniel Bernulli and anther is Blase Pascal. Bernulli cnducted an experiment n fluid flw and gives fluid flw equatin t the wrld and at same perid Pascal develped science f hydraulics. [ii] b. Pascal's Hydraulic Principle: Accrding t Pascal's law "The fluid pressure in an enclsed vessel s is unifrm in all directin". Cnsider a vessel having tw surfaces and having area A1 and A2 respectively. Als F1 and F2 be the frces acting n area A1 and area A2. Page N:435

4 Fig VI.b.1: Pascal s Hydraulic Mdel[i] Cnsidering surface 1 having area A1 and frce F1. Therefre, Pressure acting n surface 1 is given by: P1 = F1 / A1 (1) Similarly, it is given by: P2 = F2 / A2 (2) As the pressure is same in all the directin, the smaller pistn feels a smaller frce and a large pistn feels a large frce. Therefre, a large frce can be generated with smaller frce input by using hydraulic systems. P1 = P2 F1 / A1 = F2 / A2 (frm eq n. 1 &2) Fluid des nt absrb any kind f supplied energy and it is capable f mving much higher lad s and prviding much higher frces due t the incmpressibility. [i] VI. WORKING AND MODIFICATION a. Wrking: Hydraulic puller perfrms the peratin f remval f bearing. Hydraulic pulling cnsists f adjustable mechanical jaw puller inbuilt with the hydraulic jack. When the pump is perated, plunger cmes utside. Then mechanical jaws are adjusted belw the bearing and again the pump is perated. During peratin, hydraulic jack applies cntinuus pressure n shaft and mechanical jaw remve bearing frm shaft. We can refer Fig. VII.2: Hydraulic Puller with External Pump [iii] t understand the mdel f said hydraulic puller. A skilled persnnel is required fr peratin f such Hydraulic puller. [ii] b. Need fr mdificatin: Page N:436

5 As the cst f such hydraulic puller is high, due t the presence f external hydraulic pump, there are a lt f valves in this mechanism, namely directinal cntrl valves, pressure cntrl valves, flw cntrl valves, etc. use f spring return mechanism. Making the size f puller very large. This hydraulic puller requires prper handling hence the chances f leakage are high, these pullers are need t be maintained time t time fr better perfrmance, the maintenance cst is als high. Thus sme mdificatins are need t be dne s as t reduce the verall size f the system and make it easy fr peratin. c. Cncept design f Hydraulic puller: In this cncept design, the wrking mechanism f prpsed hydraulic bearing puller is based n the principle f Pascal s law. We can design the hydraulic cylinder in such a way that it can prduce huge amunt f frce at the plunger end by a small displacement f mechanical screw frm the ther end. The btained frce is used t push the shaft. The bearing is held in place by clamping arms by prper adjustments dne with the help f arm clips. Thus, bearing is remved safely withut causing any casualties. Advantages: Eliminatin f external pump. Reductin in length f hydraulic cylinder. Reductin number f valves. Eliminatin f spring return mechanism. Lw cst due t eliminatin/reductin f abve cmpnents Reduced risk f leakages. Maintenance cst is lw. Skilled r unskilled persnnel can perate the device. Page N:437

6 Disadvantage: Cylinder strke length is cnstant. Fig. VI.c.1: Cncept design f Hydraulic Puller VII. FIGURES AND TABLES Fllwing are sme tls that are used tday t remve bearings frm shaft. Cst 2,900/- Capacity Weight Dimensin 20 kn Kg. 270 x 180 x 36 mm Fig. VII.1: Mechanical Jack Screw bearing remver [vi] Page N:438

7 Cst Capacity Weight Dimensin 24500/- (shipping incl.) kn Kgs. 350 x 229 x 85 mm Fig. VII.2: Hydraulic Puller with External Pump [iii] Fig. VII.3: Traditinal Hammering remval methd. [v] VII. CONCLUSION By using Pascal s Law, we can design a cmpact hydraulic bearing puller. The purpse f this mdificatin is t simplify the peratin f remving the bearings withut damaging the bearing surface and the shaft edges, prtability f the device, lw cst and safe t use. And thus, increasing the life f bearing surface. REFERENCES The fllwing papers are being studied and are referred fr the prject. These papers belng t varius authrs, having varius papers related t the Hydraulic Bearing Puller. i. ii. Rakesh Y. Suryawanshi, Pranay S. Ramteke, Niraj Patil, & Deepak Kumar. (2015, April). DESIGN AND FABRICATION OF HYDRAULIC BEARING PULLER AND PUSHER. Internatinal Jurnal fr Innvative Research in Science & Technlgy, 1(11), iii. PULLER-PORTABLE-REVERSIBLE-JAW- SPREAD/ ?hash=item3aef2d543a:g:Ia4AAOSw0HFZpII0 iv. v. vi. Page N:439