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Effective November 1, 2000 REMOVAL OF SIMSITE® IMPELLERS: Simsite® Impellers should never be forced off the shaft. Because of the slight swelling of the Simsite® Impeller bore, the impeller may “stick” on the shaft if the impeller is wet. Let the Simsite® Impeller dry or use a heater or dryer (low heat) and the impeller will slide off the shaft. If necessary use a soft mallet and gently tap the impeller off the shaft.   WARNING Never use a hydraulic press or any pullers on a Simsite® Impeller. Never use high heat or a torch on ANY Simsite® parts.   REMOVAL OF SIMSITE® IMPELLERS IF THE RING CLEARANCES HAVE CLOSED: When Simsite Rings are new, they may swell and may stick” if immersed in a fluid without the pump operating for a long period of time. Even if the pump is drained after a ‘test operation,” there may be enough fluid in the bottom of the casing to “seize” the pump. If this should happen, the pump should be completely drained (dry) and a heater or dryer (low heat) should be placed near the impeller and rings. When the impeller and rings have dried, the clearances will open back up to the original size. Never exceed 250 degrees F. WARNING Do not use an open flame or exceed 250 degrees F.   DETERMINATION OF CLEARANCES BETWEEN WEARING SURFACES: The diametrical clearances between Simsite® Casing Rings and Simsite® Wear Rings are provided on Table 2. It should be noted that these clearances are determined for dry Simsite® Casing Rings and Impellers. If the Simsite® Casing Rings are used in conjunction with a metal impellers, or if Simsite® Impellers are used with metal rings (Sims does not recommend the use of metallic rings with Simsite® Impellers because they do not wear as well as Simsite Rings, they are not as efficient, they are not as forgiving, and they will seize if not installed properly.) these clearances should be reduced by 25% (The clearance should be 75% of the standard Simsite to Simsite clearance). If a Simsite Casing Ring requires a press fit into a pump casing, the amount of interference fit is added to the dry factory set clearance. If the Simsite Rings have been in service or immersed in a fluid, they must be allowed to dry for a 24 hour period prior to measurement because of the slight swelling and thermal expansion of the composite.   WARNING After installing a new Simsite® Impeller, it is important not to leave the pump flooded without running the pump for at least 72 hours. During this 72 hour period, the rings will expand to the specified operating dimensions. If for some reason, the pump is left flooded but not running for an extended period of time (more than 3 days), the pump must be rotated at least twice a day until it is started.   MACHINING SIMSITE® IMPELLER DIAMETERS: Simsite® impeller diameters are set at the Sims Factory. If it is necessary to turn down the impeller diameter, it is strongly recommended that the customer return the impeller to Sims for proper modification. If it is absolutely necessary to trim the impeller diameter, then the Simsite® Impeller should be assembled on the original pump shaft or on a “working mandrill” and machined in the direction of rotation of the impeller.   WARNING If the impeller is machined in the incorrect (opposite) direction, stress cracks might be induced and the impeller could possibly fail in service. Simsite® impeller should never be “chucked” into a lathe for machining. Stress cracks most probably will be induced by the pressure of the jaws and the impeller might fail in service.   SIMSITE® IMPELLER BALANCE: New Simsite Impellers should not be balanced because they are balanced by design. Simsite Impellers are precision machined on a 5-axis machining centers and therefore are naturally balanced (there are no casting imperfections, defects, or cooling distortions). Unlike cast impellers, the center of axis or rotation is in the center of the Simsite® Impeller. Since Sirnsite Impellers will not corrode in salt or brackish water, like metallic impellers, they will not go into an "unbalanced situation” and therefore do not need to be balanced. The Simsite Impellers are also approximately 1/6 the weight of a metallic impeller which reduces shaft deflection (in both the dynamic and static conditions), vibration, bearing loading, ring and sleeve wear.   INSTALLATION OF SIMSITE® SLEEVE BEARINGS: When Simsite® Guide Bearings are PRESS FIT into the pump casing or bearing housings:   Prior to the installation of Simsite® Sleeve/Guide Bearings, the bearing areas in the pump casing or bearing housing should be cleaned and all burrs removed. The bores should be indicated to make sure that they are true (concentric). If the bearing housing bore is not running true, it must be machined before the Simsite® Guide Bearing can be installed. When Simsite® Guide Bearings are press fit into The Bearing housings, they are pressed in using Interference fits similar to Simsite® Casing Wear Rings. It is necessary to assure these bearing housings are true and free of any burrs prior to the installation of Simsite® Bearings. The interference is recommended to be .001 inches per diametrical inch, with a minimum of .003 inches and a maximum of .010 inches. The Simsite® Bearings can be chilled or frozen to facilitate pressing the bearings into the pump casing or bearing housings. A soft mallet can be used to gently press the bearings into the housing. Simsite® Bearings should be secured in the housings with Simsepoxy glue and 2 to 4 set screws. The clearance between the Simsite® Guide Bearing bore and the shaft or sleeve diameter should follow the guidelines of Table 3 (on Page 6) and should never be less than .010 inches.   [ Pervious Page ] 1  2  3  4  5  6 [ Next Page ]