The ability of a mechanical seal to meet its performance objectives depends upon a wide range of factors involving equipment design, operating conditions, and support systems. Isbn valves are the components in a fluid flow or pressure system that regulate either the flow or the pressure of the fluid. Ksb mechanical seals for water and waste water applications. Sometimes operating conditions change to become quite different from the specific conditions for which the seal was intended. Why continuous seal chamber venting on vertical pumps.
The asp type 1 mechanical seal single spring seal dimensionally conforms to astm f151194 and for most applications is a direct drop in replacement for an original equipment seal. Application guidelines was created as a tool to be used by those who purchase or specify mechanical seals, as well as by the end users of rotating equipment in a wide variety of industries. Pumps installed on ships must be extremely reliable and durable. Mechanical seals are designed to overcome these drawbacks. The materials of seal construction, particularly the sealing faces and elastomers. Both the seal chamber and the stuffing box have the primary. Mechanical shaft seal types and sealing systems grundfos. 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. As previously stated, a pump with a throughshaft is not leakproof. It is used for services where leakage to atmosphere must be collected or diluted.
Packing although mechanical seals had been around for many decades, by 1955 industry had converted only a small percentage of pumps from packing to mechanical seals. The main parts of the mechanical seals are please refer the figure above. Design single mechanical seal type dynamic, balanced operating pressure up to 25 bar dynamic up to 37. The head is statically sealed to and rotates with a pump shaft. This type of mechanical seal can be used regardless of direction of rotation, this is because the acting torque is not transmitted through the coils. Size head ring ring bore code notes pump nameplate data mfg. Instead the torque is driven along the rubber bellow which fits on the shaft. Sealing systems for pumps sealing systems for pumps. Increase seal chamber pressure and fluid vapor margin. The mechanical shaft seal is essentially a throttle arranged around the shaft. Model 3196 iframe installation, operation, and maintenance manual 5 introduction and safety introduction purpose of this manual the purpose of this manual is to provide necessary information for.
A mechanical seal is simply a method of containing fluid within a vessel typically pumps, mixers, etc. On both of the above setups, the installation of a suitable device is required to seal. Every centrifugal pump must accommodate a spinning shaft while mechanically maintaining fluid or gas contained in the wet end of the pump. Application guidelines was created as a tool to be used by those who purchase or specify mechanical seals, as well as by the end users of. Goulds seal plus sp1 and sp2 are changing all that. Introduction to failures failure of the mechanical shaft seal is the most common cause of pump downtime. A dual mechanical seal offers a second outer seal to contain the. If you are unable to identify the seal, it will be necessary for you to.
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. It prevents the vaporization of the pump fluid between the seal faces. Mechanical seals for pumps how mechanical seals work. The seat is statically sealed to a nonmoving cover. Used where the seal chamber pressure is at discharge pressure mainly vertical pumps. Basics concepts of operation, maintenance, and troubleshooting, part i.
Chesterton company for expertise in mechanical seals in design, selection, installation, field service. M pumps process srl via dellartigianato, 120 45015 corbola ro italia tel. From the company you trust for the best process pumps in the industry, look to goulds now for the most economical and reliable seal alternatives. A few basic components and principles in mechanical seal design contribute to a working seal at the interface of the rotating shaft and stationary pump mixer seal chamber housing. Failure to observe the instructions contained in this manual could result in personal injury and. The mechanical seals are now available in wide variety of designs suitable for number of applications.
Mechanical seal technology and selection eagleburgmann. A mechanical seal is a shaft sealing device, which forms a running and dynamic seal between the. Its nonclogging single spring mechancial seal design makes it ideal for pulp and paper, waste water, and many other demanding pump shaf seal applications. Centrifugal pumps wate tc 9 4 ordering information 9 nominal impeller diameter pump model volute design rotation shaft seal fit impeller material model description order no. To install a seal, the pump would have to be taken. For years, conventional mechanical seals have been used in applications where, often due to cost, cartridge seals were prohibitive. Mechanical face seal replacement how to use this catalogue locate the manufacturer of the equipment.
This document is intended to clarify what to expect on mechanical seals found in colfax products. The mechanical seal mechanical seals have the purpose of preventing leakage of a fluid liquid or gaseous through the clearance between a shaft and the fluid container. A mechanical seal consists of 2 principle components. Mechanical seals are usually endface seals or rotatingface seals, but in some designs they can be circumferential or even a hybrid of liptype seals. The stationary part of the seal is fitted to the pump housing with a static seal this may be sealed with an oring or gasket clamped between the stationary portion and the pump. Sealplus mechanical seals goulds pumps pdf catalogs. Typically mechanical seals are installed on pumps and mixers. Api 682 most common plans and sealing systems castle. Clean, nonpolymerizing fluids at moderate temperatures. Viking universal seal pumps series 124a, 4124a, 124ae.
When the sealing is achieved by means of packing, the chamber is referred to as a stuffing box. The mechanical seals are robust components so they require very less maintenance. Increase your ability to specify seals to improve mechanical seal reliability mechanical seals for pumps. Our innovative, awardwinning mechanical seals for pumps, agitators, mixers, and other rotating equipment simplify installation, improve reliability, and extend the performance of fluid handling. It reduces leakage between the pump and the surroundings to an absolute minimum.
The shaft seal is exposed to widely varying operating conditions. The complete product portfolio of systems and components for cooling, flushing, pressurization and supplying liquid and gaslubricated mechanical seals e. Their main job is to prevent the pumped product from leaking into the environment and are manufactured as single or double seals. Mechanical seals are devices that seal machines between rotating parts shafts and stationary parts pump housing and are an integral part to the pump. Unlike an oring seal, the hydraulic diameter of a bellows seal is not a fixed geometric value.
Figure 1 shows a typical centrifugal pump, which highlights its constituent parts, including the mechanical seal. Mechanical seal applications mechanical seals the shaft seals used in rotating machinery such as pumps, hydraulic turbines, agitators and centrifuges play an important role in maintaining the safety and economic efficiency of machinery. Seal type the mechanical seal shown in the pump photograph is a type 1 mechanical seal. Recirculation from pump seal chamber through a flow control orifice and back to the seal. Viking pump a unit of idex corporation cedar falls, ia 2007 section 630 page 630. Figure 1 typical high pressure, high temperature process pump introduction mechanical seals vs.
Sealing systems for pumpssealing systems for pumps part i. This article will explain what a mechanical seal is and the key design features that make them work. A mechanical seal is a method of containing fluid within a vessel typi cally pumps where a rotating shaft passes through a stationary hou sing or occasionally. The chapter describes mechanical shaft seals used in grundfos pumps as examples of the variety of shaft seal solutions for different. With a lower k value, the safety against thermal overload will increase, but the mechanical seal may also lift off more easily. Within this scope, not only is it important to locate spare parts to make. These seals are generally used in sewage applications and waste water pumps. A mechanical seal, figure 1, consists of a stationary member seat. The difference between single and double mechanical seals. Mechanical seals consists primarily of a rotary seal face with a driving mechanism which rotates at the same speed as the pump shaft, a stationary seal. Included in this list is the selection of the materials of construction of the seal.
Sarbs pump maintenance seminar, june 7, 2012 factors influencing leakage seal face condition runningin process process influences stability of seal face condition of the secondary seals face deformation caused by temperature and pressure vibration and stability of the machine operating mode of the plant characteristics of the sealed fluids. Heat exchanger the rwt23 tube in tube heat exchanger is used to cool the pumped fluid in the seal chamber of single or double acting mechanical seals. Mechanical seals areconstructed of a wide range of materials. The head has a springloaded, highly polished, very flat face that is also frequently pressureloaded against that same seat face. The mechanical seal is exported to many countries, still it has provided supporting services for many domestic companies. The single mechanical seal includes the spacer sleeve for the pump, so it can be fitted without requiring an adjusting dimension. At utex, we refer to this type as rs1 the assembly shown in the pump is configured with a. Mechanical seals the shaft seals used in rotating machinery such as pumps, hydraulic turbines. The seals are arranged by shaft size from smallest to largest. Whyend viewend view continuous seal chamber venting on vertical pumps. Mechanical shaft seals this section briefly describes the design and elements of the mechanical shaft seal. Nspl pump seal design api 682 based on api 682, all mechanical seal shall be cartridge design.
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