SIMSITE® TRAINING MANUAL

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SIMSITE® TRAINING MANUAL

WHAT IS SIMSITE®?

Simsite is a graphite reinforced composite developed and patented by the Sims Pump Valve Company. It is a thermoset laminate which consists of combination graphite fibers interwoven in a continuous weave. The fibers are interwoven in a bi-directional or tri-directional weave for maximum strength. The fibers are set in either a phenolic or an epoxy resin. The strength of Simsite can be modified by either increasing or decreasing the fibers, the type of weave, the thickness of the fibers, or the resin per square inch of fibers.

Sims has been manufacturing structural composite pump parts for over 25 years and engineered composite pumps for over 10 years. Our composites have improved through the years as new technology in machining and structural composite and resins have developed. Today, our impellers and pump casings are precision machined on 5-axis machines on the outside as well as the inside from solid blocks of our composite material.

All of the composites Sims manufactures are structural. In other words, the reinforcing fibers are layers of interwoven continuous weave fibers cross stitched and laminated into a solid block with a thermoset resin. The fibers we use are not chopped or separated. Rather, they are continuous for structural strength and integrity.

Today, many of the other pump companies are offering a line of what they call "composite pumps." The "composite" they are referring to is not structural. Rather, it is cast or molded. In order for a part to be cast or molded, short length fibers or chopped fibers must be used as a reinforcing material. Also, many of them use "fillers" in their manufacture. We looked at this less expensive procedure years ago and decided against it because it was an inferior process in our opinion which was subject to many problems. When our competition casts or molds what they call composite parts, they must use chopped fibers or strands of fibers as a reinforcement which reduces the material's strength and subjects the piece to casting and molding problems such as internal voids, casting imperfections and surface cracking.

The standard grade of Simsite is SMS-300, which is a graphite fiber reinforced composite with phenolic resin. This is our most popular and versatile composite and is used to manufacture pumps, Composite Impeller, Composite Impellers, Impellers, Casing Rings, wear rings, guide bearings, frame adapters, back plates, head covers, water boxes, strainers, valve parts, etc. This composite is excellent in salt water, brackish water, all petroleum products, chlorine, and most salts.

SMS-302 is our U.S. Navy approved material for use in pump impeller, casing ring, bearing and sleeve applications. This grade of Simsite uses the same graphite reinforcement as SMS-300 except that it is double passed, quarter turned and cross laminated. It also utilizes a low moisture absorption high temperature resin system. (1.25 X Book Price)

SMS-325 is our premium grade bearing material. It has a special liquid lubricant built into the resin system as well as other lubricants. It is a little more expensive than our standard bearing material. (1.20 X Book Price)

SMS-375 utilizes a higher strength graphite fiber reinforcement with epoxy resin. This composite is used primarily for chemical resistance, and applications where high mechanical strength are required. It is more expensive than our standard grade of SMS-300. (1.50 X Book Price)

SMS-400 is our high temperature composite which can take 400 degrees F. continuously. It utilizes an aramid fiber reinforcement and is yellow in color. (1.75 X Book Price)

SMS-480 is used for applications in contact with food. It utilizes a melamine resin system with bleached linen interwoven fibers. The composition of SMS-480 is approved for used by the U.S. Department Of Agriculture. (1.75 X Book Price).

SMS-500 is our maximum strength composite. The tensile strength on this material is in excess of 100,000 psi . It is used only for special applications such as non lube compressor rings where this tremendous strength is required. It is very expensive. Call or fax for a quote.

WHAT ARE THE ADVANTAGES OF SIMSITE OVER OTHER THERMOSET COMPOSITES OR THERMOPLASTIC COMPOSITES?

STRENGTH -- -- Most thermoset or thermoplastic parts are either cast or compression molded. If they have reinforcement, the fibers must be chopped up so that the resin and fibers can be cast into a pattern or shape. Once you chop up the reinforcing fibers you limit your strength. You also do not have much control over the concentration or placement of the chopped up fibers. Therefore, the maximum tensile strength you can achieve using cut fibers is approximately 8800 psi.

Simsite parts are not cast or compression molded. Rather, they are 100 % machined on the inside and outside from a solid block of material. The reinforcing fibers are not chopped up, they are continuous for high strength. Sims has complete control over the amount and strength of reinforcement in the Simsite composite.

ACCURACY -- -- When parts are cast or molded there are always imperfections and distortion. It is very difficult to maintain accuracy on precision and complex parts.

Simsite parts are precision machined from a single reference point on CNC (Computerized Numerically Controlled ) machines. In addition to being very accurate +/- .001 inches, they are completely symmetrical and therefore do not have to be balanced.

HEAT - -- A thermoplastic will start to distort and melt at elevated temperatures approximately 160 degrees F. Simsite utilizes a high temperature thermoset resin system. This high temperature thermoset resin will not deform or melt at the upper range of its operating temperature. Once a thermoset resin is set it can not be altered, reused or changed. The standard grades of Simsite can take 300 degrees F. continuously and grades SMS-400 and SMS-500 can take 400 degrees F. If the temperature exceeds approximately 600 degrees F., Simsite will start to char.

9 REASONS TO USE MACHINED SIMSITE PARTS:

ECONOMICS -- -- It is economical to use machined Simsite parts for small or intermediate numbers of pieces. There are no expensive casting patterns or molds necessary to pay for. Also, there are no tooling costs when you use Simsite.

CLOSER TOLERANCES -- -- Closer tolerances are possible when you machine. A cast part cannot maintain such tight tolerances.

THICKER AND STRONGER WALLS -- -- When we machine Simsite parts we can design and make the walls as thick as we would like, increasing strength and longevity. Cross-sections greater than 1/4 inch generally cannot be molded on precision parts because shrinkage will cause surface marks (depression) and internal voids. Parts with thick wall sections are extremely difficult to mold, but can be easily machined.

BLENDING SECTIONS -- -- Parts with multiple undercuts and adjacent heavy and thin sections are difficult to mold but are easily machined. Also, if thick and thin sections of a molded part are not blended together gradually, internal stresses, part distortion, and cracking can occur.

NO DRAFT -- -- Machined Simsite parts do not have a mold draft. Draft is the taper required in mold cavities that allows the part to be ejected. This may mean that part surfaces will not be parallel or straight compromising the part integrity and function. A Simsite bushing or sleeve bearing, for example, does not have to be tapered and, therefore, the load is dispersed evenly across the entire inside diameter of the part instead of being concentrated on the smaller diameter end of the bushing.

LOW INTERNAL STRESS -- -- Machined Simsite parts have low internal stress. Molded parts can have internal stresses which can cause warpage and cracking.

SMOOTH SURFACES -- -- Machined Simsite parts have extremely smooth surfaces as a result of machining and also the graphite in Simsite which acts as a natural lubricant. Molded parts must be ground or polished to remove casting imperfections; or degated, which results in surface blemishes and the gate area may be a stress riser. Machined parts do not have scars as a result of grinding or gate removal. Also, machined parts are free of surface indentations behind ribs and bosses.

GREATER DESIGN FLEXIBILITY -- -- Since all of our Simsite products are machined, the size or design of a part can be altered at a moment's notice. This is possible because there is no mold or pattern to be modified. Similarly, part changes can be made without concern for different shrinkage rates, which can affect the design of a mold or pattern.

NO WELD LINES -- -- Machined parts have no weld lines to act as stress risers. Molded parts usually have weld lines, which occur when the melt flow travels around pins and bars in the mold cavity. The weld area is the weakest part of the piece.

THE DECISION TO USE SIMSITE COMPOSITES IN ENGINEERING IS DRIVEN BY SEVERAL IMPORTANT FACTORS NOT EASILY OBTAINABLE WITH ALLOYS:

1.) REDUCED WEIGHT

2.) INCREASED PERFORMANCE

3.) INCREASES THE LIFE OF THE SYSTEM

4.) REDUCES SHAFT DEFLECTION & BEARING LOADING

5.) ELIMINATES THE POSSIBILITY OF STRESS CRACKS ( HIGH FRACTURE TOUGHNESS)

6.) CORROSION & OXIDATION RESISTANCE

7.) FATIGUE RESISTANCE (STRUCTURAL COMPOSITES HAVE EXCELLENT DUCTILITY)

8.) CAN MAKE DESIGN CHANGES EASILY TO SOLVE

ADVANTAGES OF USING SIMSITE:

CORROSION RESISTANCE - - Simsite will not corrode in Salt Water, Brackish Water, Chlorine, Petroleum products, and in most acids, alkaline, and salt solutions.

LIGHT WEIGHT - - Simsite is approximately 1/6 the weight of a cast bronze or stainless steel part. With rotating equipment, reducing the weight or mass reduces the start up torque, bearing load, and the radial movement should an imbalance occur.

MECHANICAL STRENGTH AND INTEGRITY - - Simsite is a structural composite with an extremely high strength to weight ratio. All of the reinforcing fibers are interwoven in a continuous weave. The composite is not subject to internal voids, cracking, breaking, distortion, melting, or wicking.

LOW COEFFICIENT OF FRICTION - - Simsite has loose graphite embedded in the resin as well as structural. The graphite acts as a natural lubricant reducing the coefficient of friction. Simsite bearing material has additional lubricants embedded in the resin system permitting a period of DRY RUNNING should that ever occur.

ELECTROLYSIS IS ELIMINATED - - Since Simsite is comprised of non- conductive structural graphite, is inert and will not conduct electrolysis. The more inert material you can put into a pump the less electrolysis will occur. Therefore, all metallics should be replaced with Simsite to eliminate electrolysis all together.

SIMSITE CASING RINGS - - ADVANTAGES:

SIMSITE RING CLEARANCES CAN BE REDUCED WITHOUT FEAR:

Traditional metallic rings require a clearance between the impeller wear ring and the casing ring. If the clearance is too small the rings will touch because of impeller imbalance (both mechanical and hydraulic) and the radial or axial movement of the rotating element. When metallic rings touch tremendous heat is generated and they will gall or seize causing tremendous damage to the pump and motor. If the clearance is set too large there will be a tremendous loss of efficiency and pressure as the fluid being pumped leaks back through the gap (excessive clearance) between the wear rings and the casing rings. Simsite rings require a clearance, however, the clearance is not as critical as metallic rings because if they should touch they will "wear in" as opposed to seizing and galling.

SIMSITE RINGS ARE SELF LUBRICATING AND HAVE BETTER SEALING PROPERTIES:

Simsite Casing Rings and Simsite Wear Rings offer many advantages over the traditional metallic rings. Because they will not seize or gall if the clearance is set too small they offer a much better sealing surface. Clearances can be set tighter than traditional metallic rings and therefore the efficiency of the pump is increased. Should the rings touch they are self lubricating and will wear in an even pattern without causing damage to the rotating element. As the pump continues to operate over a long period of time the clearances will eventually open as the rings wear; however, because of the nature of the composite they will try to close. This means that the Simsite rings have a much longer life than metallic rings.

SIMSITE RINGS REDUCE ELECTROLYSIS AND PREVENTS "WASH OUT" IN THE PUMP CASING:

Simsite Casing Rings have another tremendous benefit -- they prevent "wash out" in the pump casing. Unlike metallic rings, the Simsite composite ring will seal against the pump casing ring landing surface. Because of the tight seal against the metal casing the fluid being pumped cannot get behind the ring and wash out the metal. This is one of the most common forms of pump failure which can be totally eliminated by installing Simsite Casing Rings.

SIMSITE IMPELLERS -- ADVANTAGES:

ELECTROLYSIS IS REDUCED OR ELIMINATED

Simsite is an inert material and will not conduct electrolysis. The introduction of a Simsite Impeller will reduce the amount of electrical current in the pump. The more inert material that is introduced into the pump the lower the current and the lower the electrolysis.

MECHANICAL BALANCE

Simsite impellers are machined as opposed to being cast. They are machined from a center reference point and are symmetrical. Because of their symmetry, they do not have to be balanced because they are already 100% in balance. Unlike a metallic impeller, they will remain balanced in a corrosive environment enabling the pump to last much longer before it needs to be overhauled.

HYDRAULIC BALANCE

It is hydraulic balance which can cause a shaft to bend and a rotating element to thrust in one direction or another. Because Simsite impellers are 100% machined, all exit areas are identical eliminating any potential for hydraulic imbalance as a result of different exit areas or casting imperfections.

RADIAL FORCES ARE REDUCED WITH SIMSITE

One of the best advantages a Simsite Impeller has over any other impeller is that it can be designed for the BEP (Best Efficiency Point) where radial force is zero. A pump that is not operating at its BEP is subject to radial forces which are severe if the pump is operating close to shutoff or far out on the curve. Radial Vibration is a leading cause of pump failure.

Corrosion Problems are Solved:

Simsite Impellers will not corrode in salt water or in brackish water. They are corrosion resistant to salts, all hydrocarbon fuels (gasoline, oil, or oil refinery byproducts) and solvents as well as most acids and alkaline solutions. Simsite Impellers are not subject to corrosion attack from chlorine or stress crack corrosion.

Light Weight:

A Simsite Impeller is approximately 1/6 the weight of a bronze or stainless steel impeller. The light weight makes a tremendous difference in rotor dynamics: Shaft deflection (both dynamic and static) is substantially reduced as well as the loading on the bearings. Although this makes a difference on all rotating elements, it is particularly important for "floppy" or marginally designed shafts. Simsite impellers becomes extremely important in multistage pumps because the benefit of the light weight is multiplied by the number of stages.

Energy Savings:

Because of the low coefficient of friction, light weight of the Simsite Impeller, smoothness of the Impeller vanes, lower amount of leakage between the casing rings and the impeller wear rings, and because Simsite Impellers are 100% machined from a center reference point on a 5-axis machining center, Simsite Impellers operate at higher efficiency than other impellers. This higher efficiency translates into less start-up motor load and lower amperage for the motor. Naturally, the larger the impeller the greater the energy savings for the motor. Conservation is becoming a more and more important issue and should not be overlooked .

Simsite Impellers Reduce Noise and Vibration:

Simsite Impellers are designed to operate at the BEP (Best Efficiency Point) where radial forces are at their lowest. Balance problems are also eliminated with Simsite impellers which further reduces vibrations. Furthermore, Simsite absorbs noise and vibrations, and cushions shock waves passing through the composite. Composites provide inherent damping capability because of their viscoelastic (combination of viscous and elastic) behavior. When a composite material is strained in an oscillatory manner, stress and strain are out of phase. The reduction of noise and vibration becomes an important safety factor for rotating equipment.

Cavitation Problems are Eliminated or Reduced through Re-Design using Simsite Impellers.

Traditionally, cavitation damage was reduced by installing inducers and/or baffles, injecting air into the pump, or postponed by switching materials. Most of these traditional methods did not solve the cavitation problem; rather, they only extended the life of the impeller and/or pump and were very expensive. Today, a more permanent solution exists: Change the impeller design. With the CAD/CAM (computer aided design/computer aided machining) technology that is now available, the existing impeller can be redesigned to meet operational requirements. Because Simsite impellers are designed and precision machined using CAD/CAM and fluid modeling technology, design changes can be made very easily with very little or no cost.

Simsite Impellers offer Safety to the Customer.

Catastrophic failure is a thing of the past when you install Simsite Impellers in your pumps. In the unlikely event of a pump failure, the composite becomes sacrificial and in many cases acts like a guide bearing saving the rotating element and the pump casing. Usually, there is only minimal damage to the Simsite impeller which can be repaired at the factory. Additionally, the light weight of the Simsite Impeller (1/6 the weight of a bronze or stainless impeller) is an important safety factor when assembling or disassembling the pump. Also, should a foreign object become lodged between the vanes creating an imbalance, the vibration and corresponding damage will be reduced accordingly if a Simsite Impeller is operating.

CENTRIFUGAL FORCE IMBALANCE IS REDUCED WITH A SIMSITE IMPELLER.

If the center of gravity of the impeller is not in the center of axis of rotation, then an imbalance will be created. This force caused by an imbalance in the rotating element is calculated as follows:

The benefit of using a Simsite Impeller is that the center of gravity is always at the center of the axis of rotation because it is machined on a 5-axis machine and is not subject to casting imperfections. Also, the weight of a Simsite Impeller is approximately 1/6 that of a cast metal impeller, therefore if an imbalance should exist the force (Fc) would be reduced accordingly.

STATIC SHAFT DEFLECTION IS REDUCED WHEN SIMSITE IMPELLERS ARE USED.

The critical speed of a shaft is linked to its static deflection. Shaft deflection depends upon the weight of the rotating element, the shaft span, and the shaft diameter. The basic formula is :

This formula is often shortened since a significant portion of rotor weight is in the shaft and impeller, and the methods of bearing support and modulus of elasticity are common to similar designs, deflection is often shown as L4 / D2. This shortened formula should not be used when using a Simsite Impeller since a Simsite Impeller is only one sixth (1/6) the weight of a metallic impeller and therefore the shaft deflection is substantially less. Rather, the long formula should be used.

Small frame pumps are often operated at high speeds in order to obtain high flow rates. This severely stresses the light weight construction of the pump and results in higher levels of shaft vibration. A vibrating shaft subjects the seals, bearings, rings and sleeves to abuse and, because of this, small frame pumps suffer a disproportionate number of seal, bearing, ring, sleeve, and shaft failures.

SHAFT DEFLECTION -- THE DYNAMIC CONDITION:

Inside a pump is a shaft rotating at a specific RPM. If that shaft has any loading upon it from either the impeller or the coupling, then this loading or force is transmitted as a vibration. The amplitude of a vibration resulting from this force or loading, that is the actual physical displacement of the shaft in the radial direction at any point is dependent on the nature and extent of the bending forces acting on the impeller. This bending force F is a complicated dynamic force acting on the impeller. The formula for shaft deflection in the dynamic condition is a follows:

The magnitude of F is dependent upon the following forces:

1. Radial Force -- Unequal pressure distribution in the volute at reduced capacities and increased capacities caused by operating the pump away from the design point or best efficiency point (BEP) which results in higher radial loads which in turn induces greater vibration and shaft deflection.

A Simsite impeller is designed to operate at the BEP where radial forces are at their lowest.

2. Centrifugal Force -- The force caused by an imbalance in the rotating element or impeller. This force depends heavily on the weight of the impeller, the distance from the rotating axis to the center of gravity and the rotating speed.

A Simsite impeller is 1/6 the weight of a metal impeller. Also, the center of gravity of a Simsite impeller is also the center of axis of rotation.

3. Hydraulic Force -- Unequal pressure distribution caused by improper impeller design, sloppy manufacturing methods, or casting imperfections. A common example of this would be uneven vane spacing or uneven exit ports on an impeller.

A Simsite Impeller is not cast and therefore is not subject to casting imperfections and distortion. Rather, it is machined on a 5-axis CNC machining center insuring that the vane spacing and impeller exit ports will be identical.

This formula (Y = FL3/3EI) for Dynamic Shaft Deflection is often reduced to a ratio of (L3/D4) which is referred to as the Slender Ratio. The Slender Ratio, however; does not take into account the reduced weight (1/6) of a Simsite Impeller and the significant reduction in the magnitude of (F) the dynamic force acting on a Simsite Impeller. Therefore, the long formula should always be used.

SIMSITE GUIDE BEARINGS

Simsite®  bearings are uniquely different from any other bearing material on the market. They are significantly superior to other guide bearings because they offer rigidity to the rotating element as well as self lubricating qualities without galling or seizing on the shaft. Even if for some reason the Simsite bearings are not given proper lubrication, they will not fail or seize causing tremendous destruction to the entire rotating element. The following are just some of the highlights of Simsite bearings:

SIMSITE BEARINGS HAVE A LOW COEFFICIENT OF FRICTION:

Simsite bearings have an extremely low coefficient of friction, because they have loose graphite and a liquid lubricant embedded throughout the composite which acts as an lubricant. Graphite is an excellent lubricant which gives Simsite its self-lubricating qualities. When lubricated by water, oil, or grease, Simsite is ideal for use as guide bearings, rudder bearings, stern tube bearings, oil seal bearings, and stabilizing bearings.

SIMSITE BEARINGS WILL NOT FAIL OR SEIZE ON A SHAFT:

In the event that lubrication is suddenly cut off from the bearings, Simsite will not melt or seize on the shaft like plastic or elastomer bearings. Simsite can withstand dry running for a period of time before the clearances will start to open up, but the bearings will never completely fail. This has saved the life of many rotating elements.

SIMSITE BEARINGS ARE STRUCTURAL AND HAVE HIGH MECHANICAL STRENGTH

The unusually high mechanical strength gives Simsite bearings many advantages over conventional bearings. Simsite bearings are not poured or molded, rather, they are structural -- precision machined from a solid block of Simsite material. Because the fibers in Simsite are not chopped up or cut, Simsite bearings have a much higher shear strength, bond strength, flexural strength, and tensile strength. Simsite bearings will not crack or break like carbon bearings. The high mechanical properties enable the bearings to withstand higher loads and torque requirements.

SIMSITE BEARINGS CAN WITHSTAND HIGH TEMPERATURES:

Simsite bearings can withstand extremely high flash temperatures (1000 Deg. F.) and continuous running temperatures of 300 degrees F. with standard Simsite and 400 degrees F. with a high temperature resin. Because of this unique quality Simsite will not melt, get spongy or soft, or seize on the shaft. Other bearing materials such as elastomers cannot take flash temperatures and will literally melt on the shaft if they see and dry running at all.

LONGER LIFE FOR THE ENTIRE ROTATING ELEMENT WHEN SIMSITE GUIDE BEARINGS ARE INSTALLED:

Because Simsite bearings hold the shaft more securely than conventional guide bearings, radial movement in the shaft is reduced. This increases the life of the entire rotating element especially bearings, mechanical seals and wear rings. When Simsite Guide Bearings are installed with a Simsite Impeller and Simsite Casing Rings, the length to diameter requirement of the rotating element has been substantially changed by lowering the impeller mass and by increasing the stability (support) of the rotating element by using Simsite Guide Bearings.

CORROSION, EROSION AND ELECTROLYSIS PROBLEMS ARE SUBSTANTIALLY REDUCED OR ELIMINATED WITH SIMSITE BEARINGS:

Since Simsite is basically an inert composite, electrolysis is greatly reduced. Additionally, Simsite bearings seal against the casing or bearing housings which prevents leakage and therefore eliminates corrosion and erosion damage. This is critical because it insures that the bearings will be secured properly in the casing or housing, eliminating the risk of severe damage to the entire rotating element.

SIMSITE BEARINGS REDUCE SHAFT WEAR:

Objectionable wear problems can be overcome by redesigning existing guide bearings based on geometrical consideration of clearances and surface finish and installing Simsite ones.. Simsite bearings have loose graphite as well as structural graphite fibers which ranks extremely high in anti-galling characteristics. The highly polished surface finish of Simsite bearings reduces unnecessary wear on the shaft as well as the bearings.

SIMSITE SLEEVES:

If a pump has mechanical seals then it should have SIMSITE SLEEVES. The Simsite Sleeves not only protect the shaft against corrosion and erosion, but they are light weight which further reduces the weight of the rotating element. Additionally, the Simsite Sleeves will last much longer than the metallic sleeves. Simsite Sleeves can also be used with packing.

WHY SHOULD YOU BE USING SIMSITE IMPELLERS AND RINGS IN ALL YOUR PUMPS?

* A SIMSITE IMPELLER IS DESIGNED TO OPERATE

AT THE BEST EFFICIENCY POINT.

* CORROSION RESISTANCE.

* REDUCES ELECTROLYSIS IN THE PUMP.

* BALANCE PROBLEMS ARE ELIMINATED.

* DEFLECTION IS REDUCED.

* SIMSITE IS LIGHTWEIGHT.

* RADIAL VIBRATION IS REDUCED.

* CASTING IMPERFECTIONS ARE ELIMINATED.

* LOWER COEFFICIENT OF FRICTION .

* LESS LEAKAGE BETWEEN RINGS.

* PREVENTS "WASH OUT" IN THE PUMP CASING.

* PREVENTS CATASTROPHIC FAILURE.

IMPORTANT

WHY, AND FOR WHAT REASONS, DO WE NEED TO UPGRADE EXISTING EQUIPMENT TO SIMSITE?

* TO REDUCE DOWNTIME COSTS.

* TO PREVENT HIGH FAILURE RATE.

* TO IMPROVE SAFETY FACTOR.

* TO INCREASE PRODUCTIVITY.

* TO REDUCE MAINTENANCE COSTS.

* TO REDUCE INVENTORY COSTS.

SIMSITE ® IS THE "SECRET"

* A STRUCTURAL GRAPHITE COMPOSITE

* OUTSTANDING CORROSION RESISTANCE

* HIGHER EFFICIENCY DESIGN

* MAINTAINS SUPERIOR HYDRAULIC & MECHANICAL BALANCE

* THE LIGHT WEIGHT REDUCES SHAFT DEFLECTION

* LOW COEFFICIENT OF FRICTION

*REDUCES NOISE & VIBRATION

*PREVENTS "WASH OUT" IN THE PUMP

* DESIGNED TO INCREASE THE LIFE OF EQUIPMENT

* REDUCES ELECTROLYSIS

SIMSITE IS A SOLUTION FOR THE FOLLOWING PROBLEMS:

* A PUMP NOT OPERATING AT DESIGN POINT.

* A PUMP WHICH IS SUFFERING FROM CAVITATION.

* A PUMP WHICH HAS A RADIAL REACTION PROBLEM.

* A PUMP WHICH IS SUFFERING FROM CORROSION ATTACK.

* A PUMP WHICH HAS A VIBRATION PROBLEM.

* A STANDBY PUMP IN A SALTWATER APPLICATION.

* A MULTISTAGE VERTICAL PUMP WITH BEARING PROBLEMS.

* A HORIZONTAL PUMP WITH EXCESSIVE SHAFT DEFLECTION.

USES OF SIMSITE

IMPELLERS LIQUID PISTON RINGS

CASING RINGS PUMP VALVE DISCS

WEAR RINGS GEARS

GUIDE BEARINGS PULLEYS

PUMP CASINGS HEAT EXCHANGER COVERS

POWER ENDS TUBE SHEETS

STERN TUBE BEARINGS VIBRATION BLOCKS

RUDDER BEARINGS CHECK VALVES

EXHAUST GAS FANS ROLLER WHEELS

ROTOR VANES WEAR PLATES

STRAINER BOXES CONDENSER HEAD COVERS

COMPRESSOR RINGS BUTTERFLY VALVES

COMPLETE PUMPS BALL VALVES

ROTATING ASSEMBLY BALANCE:

Assuming that the driver and shaft is initially balanced, little or no impact should occur upon the addition of a Simsite® Composite Impeller. It should not be necessary to rebalance the Simsite® Composite Impellers. Simsite® Impellers are precision machined and dynamically balanced at the Sims Factory. Upon re-assembly of the pump with Simsite® composite components, operational testing shall be accomplished. If imbalance is evident during this testing, attempt to locate the source of imbalance and make the necessary adjustments to the metallic components of the rotating assembly.

If necessary, dynamic balancing of rotating assemblies utilizing Simsite® composite components requires special consideration and procedure. Because of the Simsite® composite component's light weight relative to metallic components, and because of the matrix construction of the Simsite® material, grinding is not permitted and may be harmful to the integrity of the composite component.

Simsite® Impellers are balanced by adding weight to the impeller. (Similar to the balancing of an automobile tire except that the weight should be countersunk into the impeller). The recommended weight that has to be added to the impeller for balance should be either a monel or stainless steel set screw (8-32, 10-32, or 1/4-20). The impeller should be drilled and tapped to accept the set screws either in the side of the "wear ring area" or in the "shroud of the impeller in the middle of one or more of the vanes." The set screws should be screwed in with loctite® (or equal) and covered with a molecular compound (Belzona, Devcon, Simsite, etc.) to cover the screw.

note: Where dynamic balancing is required, the necessary weight adjustments shall be made to the metallic components of the rotating assembly, but only after the Simsite® composite balance is verified to be within the allowable limits.

THE DYNAMIC CONDITION

F is a complicated dynamic force acting on the

impeller.

The magnitude of F is dependent upon the

following:

1. Radial Force - Unequal pressure distribution

in the volute caused by operating the pump at

capacities other than the design point (BEP).

2. Centrifugal Force - Force caused by an imbalance

in the rotating element or impeller.

F_c = Wp²N²R/900g

* Note that the magnitude of Fc depends

heavily on the weight of the rotating body.

3. Hydraulic Force - - Force caused by improper impeller design, casting imperfections or sloppy manufacturing methods.

EXAMPLE: uneven vanes or exit port

The critical speed of a shaft is linked to its static deflection.

y = deflection, in

Consider the case of an overhung impeller. The load condition looks like this:

COMPARING METALLIC AND SIMSITE® IMPELLERS,

assume: 1- shaft of constant diameter, D composed of stainless steel.

2- weight of SIMSITE® is one-sixth that of metals.

METALLIC SIMSITE

In the case of the Shinko gvd-450, the use of a SIMSITE® impeller reduced the static deflection by a factor of three.

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