Mechanical seal of cantalever centrifugal pumps in an aromatic complex in jilin petrochemical company experienced frequent failures. Shelby scottshelby scott western region john crane incjohn crane, inc. The rotating part is axially pressed against the stationary part. The concept of the fluid being available to the pump is discussed in detail in chapter 2 of this book. Recirculation from pump seal chamber through a flow control orifice and back to the seal. Sealing systems for pumps sealing systems for pumps. Mechanical seals consists primarily of a rotary seal face with a driving mechanism which rotates at the same speed as the pump shaft, a. Spread throughout the world, this type of mechanical seal has reached an unsurpassed quality level. Every centrifugal pump must accommodate a spinning shaft while mechanically maintaining fluid or gas contained in the wet end of the pump. Mechanical shaft seal types and sealing systems grundfos.
This is commonly seen in centrifugal pumps although this challenge also exists in other equipment such as agitators, turbines, compressors, centrifuges, and blowers. M pumps process srl via dellartigianato, 120 45015 corbola ro italia tel. Spring provides positive pressure for sealing between the sealing faces. It converts the energy provided by a prime mover, such as an electric motor, steam turbine, or gasoline engine, to energy. Review different pump types commonly used understand the difference between centrifugal pumps and positive displacement pumps understand the working principle of the tuthill. Some common types of pump seals michael smith engineers. Sealing systems for pumpssealing systems for pumps part i presented by. Other than the bearings, and of course the driver, the only moving part in a centrifugal pump is the rotor. In simple words, it is a pump that uses a rotating impeller to move water or other fluids by using centrifugal force. A mechanical seal, figure 1, consists of a stationary member seat. After nearly six years of intensive work, the american petroleum institute api 682 mechanical seal standard is soon to be adopted. The general components, both stationary and rotary, are depicted in figure b. Checklist of problems vvith centrifugal pumps and their causes. Introduction to failures failure of the mechanical shaft seal is the most common cause of pump downtime.
Incorrect installation and adjustment are the causes for failure. Checklist of problems vvith centrifugal pumps and their causes centrifugal pumps are one of the worlds most commonly used devices. A mechanical seal is a method of containing fluid within a vessel pumps, mixers. The optimum life of a seal is the period between major overhauls of the pump unit. How to respond to mechanical seal leakage in a centrifugal pump in order to understand centrifugal pump leakage, its important to first understand the basic operation of a centrifugal as the flow enters through. Click on the doe seal below to move to the overview. The difference between single and double mechanical seals. Sealing systems for pumpssealing systems for pumps part ii.
Hello friends iss video me mechanical seal ko centrifugal pump me kaise install karte hai btaaya gya hai. Single seals made up of two flat surfaces that slide against each other and are pressed together by a spring. Centrifugal pump definition centrifugal pump can be defined as a mechanical device used to transfer liquid of various types. A seal piping plan is designed to improve the environment around the mechanical seal and therefore increase the performance and reliability of the seal. The pump cannot suck on or draw the liquid into the pump. Probably the most widely recognized and also most common mechanical seal used in general service, low pressure applications. Seal type the mechanical seal shown in the pump photograph is a type 1 mechanical seal. A mechanical seal is a method of containing fluid within a vessel typically pumps where a rotating shaft passes through a stationary housing or occasionally, where the housing rotates around the shaft. Introduction the mechanical seal acts as a check valve and a slider bearing. Sarbs pump maintenance seminar, june 7, 2012 seal typesseal types causes of seal failure piping plans sealinggg water usage safeunit flowmeters.
The seals are classified as h, m or l according to load, with h and m indicating heavy load and l indicating light load. Their main job is to prevent the pumped product from leaking into the environment and are manufactured as single or double seals. This document is intended to clarify what to expect on mechanical seals found in colfax products. Review different pump types commonly used understand the difference between centrifugal pumps and positive displacement pumps. This is commonly seen in centrifugal pumps although this challenge also exists in other equipment such as agitators, turbines, compressors, centrifuges, and. Berkeley b54585, model b3tpms, closecoupled centrifugal. Know and understand centrifugal pumps \ r i \ suction piping. Mechanical seals move the point of the seal away from the shaft to specially designed sealing faces that gradually wear down. The mcs is a close coupled, end suction, centrifugal pump designed for general liquid transfer service, booster service and many other general applications traditionally requiring various materials such as. As the flow enters through the impeller eye of the pump and up the impeller vanes, the fluid is at a lower pressure and low velocity. When sealing a centrifugal pump, the challenge is to allow a rotating shaft to. The rotor rotating element, is made up of the following main components. Different types of mechanical seal pump heat transfer scribd. Typically mechanical seals are installed on pumps and mixers.
Goulds 3ms1h2a4, centrifugal pump, series mcs, 3 hp, 208230. Mechanical seals technical manual brenner industrial sales. At utex, we refer to this type as rs1 the assembly shown in the pump is configured with a. Sometimes operating conditions change to become quite different from the specific conditions for which the seal was intended. Spring retainer positions and centers the spring, aiding the concentricity between the spring and shaft.
H and l types are typically singlespring seals, while the m types are multispring units. P1809b mechanical seal leak rcfa free download as powerpoint presentation. Sealing systems for pumpssealing systems for pumps part ii presented by. The materials of seal construction, particularly the sealing faces and elastomers. Under normal conditions, seals wear out much faster than the other pump parts. Since its introduction in 1994, api 682 has become the standard that sets the global tone for the procurement and operation of seal and supply systems for centrifugal pumps in the oil and gas sector as well as in the petrochemical industry. The complete cross reference for mechanical face seal replacement how to use this catalogue locate the manufacturer of the equipment. Pumps shaft sealing systems for centrifugal and rotary pumps 1 scope this international standard specifies requirements and gives recommendations for sealing systems for centrifugal and rotary pumps used in the petroleum, natural gas and chemical industries. Basics concepts of operation, maintenance, and troubleshooting, part i.
It converts the energy provided by a prime mover, such as an electric motor, steam turbine, or. The bta2 features all carbon or high quality resin impregnated carbon, aluminium oxide 96 %, is stationary and the rubber bellows are glued on collar. There are various types and arrangement of the mechanical seals being used for the centrifugal pumps. As mechanical seals can be used to seal a myriad of different products on an equally vast array of equipment, we will be primarily focusing on the use of mechanical seals on rotating shaft pumps. The obvious function is that of a check valve to prevent liquid under pressure from leaking out of the pump, or from drawing air into the pump when under vacuum conditions.
The leading types of seals used in centrifugal pumps manufacturers and suppliers in china, offers mechanical seal basics pdf with competitive price here. Centrifugal pumps can be classified based on the manner in which fluid flows through the pump. A stationary component comprised of a casing, casing cover, and bearings. Since our subject is dealing with pumps, lets first explore a basic. Standard mechanical seals are usually component seals. A mechanical seal is simply a method of containing fluid within a vessel typically pumps, mixers, etc. Sealing systems for pumpssealing systems for pumps part i. They are defined for their different functions, but their working principle is the same. The shaft seal is exposed to widely varying operating conditions. It reduces leakage between the pump and the surroundings to an absolute minimum.
Pumps of this type are called double volute pumps they may also be referred to a. If the centrifugal pump flow is too high or too low hydraulic disturbances will be present that can change the pumped fluid pressure andor temperature. This article defines centrifugal pumps, shedding light on the working, application, and types of centrifugal pumps and shall help you buy the most suitable one for your process. Mechanical shaft seal a mechanical shaft seal consists of two main components. As the name suggests, it relies on the principal of centrifugal force. Mechanical seal working animation types of mechanical seal. When sealing a centrifugal pump, its essential to allow a rotating shaft. We offer a wide selection of head types and mating ring designs and stock thousands of seals in differing materials of construction.
A mechanical seal appears expensive to buy when compared with a packing ring, but properly installed a seal will run for many years. The manner in which fluid flows through the pump is determined by the design of the pump casing and the impeller. Energy used in a pump can be engine energy, electrical energy or other non conventional energy i. Thus the mechanical seals are the devices that form the packing between the rotor and the stationary part of the centrifugal pumps to prevent the leakage of the fluid being pumped by the pump. This article will explain what a mechanical seal is and the key design features that make them work. The three types of flow through a centrifugal pump are radial flow, axial flow, and mixed flow. The mcs is a close coupled, end suction, centrifugal pump designed for general liquid transfer service, booster service and many other general applications traditionally requiring various materials such as all iron, bronze fitted or all bronze construction. The chapter describes mechanical shaft seals used in grundfos pumps as examples of the variety of shaft seal. Mechanical seal leakage in pumps how much, if at all, mechanical seals do, must or must not leak is a controversial subject for which there are few clear answers. Api 682 most common plans and sealing systems castle. The fluid must be available to the pump with sufficient energy so that the pump can work with the fluids energy. Seal basics a mechanical seal is a device used to seal the interface between a rotating shaft and a stationary housing figure 1. Mechanical seals are used in industrial pumps, compressors, and other applications where a spinning shaft protruding into a wetted process is likely to have continuous, rigorous duty. Shaft seals can take many different forms, but all serve the common purpose of keeping the liquid in the pump.
Mechanical seals explained the basics mechanical seals are leakage control devices, which are found on rotating equipment such as pumps and mixers to prevent the leakage of liquids and gases from escaping into the environment. When sealing a centrifugal pump, its essential to allow a rotating shaft to enter. No mechanical seal capable of handling applications with wide ranges of viscosities. In plan 11, product is routed from the pump discharge to the seal chamber to provide cooling for the seal and to vent air or. Classification of centrifugal pump centrifugal pumps are classified in several ways.
Mechanical seal working installation and parts explained. The mechanical seals help sealing the rotating part of the shaft against the stationary part of the pump housing. Mechanical seal technology and selection eagleburgmann. How to respond to mechanical seal leakage in a centrifugal pump in order to understand centrifugal pump leakage, its important to first understand the basic operation of a centrifugal pump. The mechanical shaft seal is essentially a throttle arranged around the shaft. Mechanical seals for pumps how mechanical seals work. Recirculation from pump discharge through flow control orifice to the seal. A rotating component comprised of an impeller and a shaft ii. The manufacturer listings are alphabetical, refer to pages 7.
Figure 1 shows a typical centrifugal pump, which highlights its constituent parts, including the mechanical seal. Their compact design permits their use in all types of centrifugal pumps. Pumps shaft sealing systems for centrifugal and rotary. Centrifugal pumps are the most widely used type of pump for the transfer of liquids. An oilfield solids control system needs many centrifugal pumps to sit on or in mud tanks.
How to respond to mechanical seal leakage in a centrifugal. Based on the equipment used in a typical 400 mw combinedcycle plant, this guide describes important details about the pump types used, offers guidance for proper selection of main and auxiliary service pumps, and describes the significance of proper operation of pumps in power plant service. Centrifugal pumps mechanical seal toegn ga gi series speck centrifugal pumps mechanical seal toegn ga gi series 1 44 pages. The shaft seal is a sealing element which seals the rotating shaft of a centrifugal pump where it passes through the nonrotating pump casing, reducing fluidleakage to atmosphere or the entry of air from outside to a certain level, and keeps wear of the sealing faces as low as possible. Centrifugal pumps can also be constructed in a manner that results in two distinct volutes, each receiving the liquid that is discharged from a 180. Different types of mechanical seal free download as pdf file. Mechanical seal configuration codes for torishima mechanical seals a number and a code indicate the configuration and materials used in each torishima mechanical seal.
Since the majority of mechanical seal applications use the pumped fluid in the seal chamber, the seal chamber pressure andor temperature will be affected. A seal that fails early by this criteria is in need of investigation. Seal chamber pressure an overview sciencedirect topics. Aug 01, 2018 hello friends iss video me mechanical seal ko centrifugal pump me kaise install karte hai btaaya gya hai. Berkeley b54585, model b3tpms, closecoupled centrifugal pump. In this type of seal often there are no metallic parts in contact with the product or, if. Mechanical seals are devices that seal machines between rotating parts shafts and stationary parts pump housing and are an integral part to the pump. The diagram shows a multistage centrifugal pump with clockwise rotation looking from the drive side, a type. Our mechanical seals promise long life, reduce maintenance, and provide automatic selfadjustment.
Abrasives and excessive heat greatly shorten the seals life span. The pump is a device that is used to transfer the fluids water, oil, gases, slurry by consuming and using mechanical work. One of the greatest advantages of a centrifugal pump is that it has very few moving parts which minimises mechanical problems and energy losses due to friction. The shaft seal is a sealing element which seals the rotating shaft of a centrifugal pump where it passes through the nonrotating pump casing, reducing fluidleakage to atmosphere or the entry of air from outside to a certain level, and keeps wear of the sealing faces as low as possible pumps are specially designed and manufactured to cater for a whole range of different applications. The types of centrifugal pumps used are sand pumps, submersible slurry pumps, shear pumps, and charging pumps. The fact of the matter is that there are three types of problems mostly encountered with centrifugal pumps.
Most common plans and sealing systems plan 53b plan 53c plan 52 used where the pumped product is. This articles describes some of the commonly used mechanical seal types like cartridge type mechanical seals, balanced type, unbalanced type, conventional, pusher, and nonpusher type of mechanical seals. Berkeley b54585, model b3tpms, closecoupled centrifugal pump, b series, 1 hp, 230 volts, 1 phase, 1800 rpm, 3 npt discharge, cast iron impeller, mechanical seal. Plan 11 is the default seal flush plan for all single seals. The improvement was made in the design of seal through analysis.
381 392 1156 141 876 48 788 298 424 1518 82 1111 345 843 70 1246 173 751 257 391 1203 1516 744 149 1259 255 1132 613 725 781 984 431 1464 690 1060 315 1316 165 1121 1453