Considering the potential cost impact, keeping compression packing functioning properly may well be the most critical factor ensuring that the pump keeps working. An oring is contained in a gland and forced to flow into the surface imperfections of the glands and any clearance gaps available to it. The design of mechanical seals is such that a thin film of liquid always exists between the seal faces. Packing materials were originally the sealing method of choice, using soft, flexible materials. Performance factors there are a myriad of factors that can affect the performance of packing.
When the stationary seal ring is of a design that can be clamped, the clamping action can easily create distortion. This chapter addresses gland design practices for solid crosssection direct compressiontype single and dual durometer seals, plasticlined seals, bdrp seals, filled seals, and grooved. When choosing the sealing option thats right for your applications, mechanical seal and gland packing seal offer both pros and cons. Their high quality design and construction requires less pressure on the gland to form the seal, which leads to. The gland at the rotating shaft of a centrifugal pump. If you continue browsing the site, you agree to the use of cookies on this website.
Our quality control methods for material and manufacturing processes ensure that all seals leaving our factories. Hydraulic seal selection guide six simple steps to seal selection to select the correct hydraulic seal for your application, please consider the following steps. In order to seal properly the oring has to deform in the application by being compressed and stretched in any number of ways. When considering gland packing vs mechanical seal solutions, mechanical seals are the best for minimizing sleeve damage. Gland packing in agitator, risk assessment for ignition source. Curtisswrights sealpro is a webbased, valvepacking database and fluid leak management program that is able to design and manage configurations, track leaks and valve repair, and uses a system of. Nov 03, 2016 by tightening a follower or packing gland against the top ring, pressure is transmitted to the packing set, expanding the rings radially against the side of the stuffing box and the reciprocating or rotating member, effecting a seal.
Mechanical seals vs gland packing mechanical engineering. The importance of packing glands correctly cannot be overemphasised. An oring can perform sealing by means of squeeze under low pressure. Whereas the gland packing is used where leakage of fluid is used for lubrication of gland as well as no hazard or loss of fluid occur. Also, the number of packing required for the seal is pend on the stuffing box pressure and depth of the stuffing box. When nonoperational, the gland nut is tightened on the packing and the drip stops. An oring is a simple and versatile ring shaped packing or sealing device. Our gland packings are square braided on the most advanced.
Application data design dimensions for oring instalation orings are normally used as seals in several ways, and dimensions of the groove or gland will also vary with the cross section of the ring. Seal implementationrelated software oring analyst rev. Hello friends i have to open one topic for discussion as tagged in topic. Control valve packing is a sealing system which normally consists of a deformable material, in the form of solid or split rings contained in a packing box packing material is compressed to provide an effective pressure seal between the fluid in the valve body and the outside atmosphere. The cut ends are staggered to prevent leakage through them. Because of this necessary tending, classic gland seals have gotten a bad rap. Under axial compression, the packing expands radially, creating a seal between the stationary body of the equipment and the dynamic surface, usually a rotating shaft. Support is particularly necessary when the ram is horizontal.
But you have to remember to loosen the gland nut next time, or you will heat score the shaft. Dec 29, 2015 for understanding the gland sealing system first we have to understand why it is required so there are two main reason. Packing seals are removed and replaced much more often than mechanical seals, which causes considerable wear and tear to the pumps as they are disassembled and reassembled. Gland packing in agitator, risk assessment for ignition source posted in industrial professionals.
Having a circular cross section that functions as a seal, in both static and dynamic applications, by being compressed between the mating surfaces comprising the walls of the gland, in which it is installed. In the case of gland packing, the sealing will take place by pressing the gland packing against the gap between the casing and shaft to control the leakage. Application data design dimensions for oring instalation orings are normally used as seals in several ways, and dimensions of the groove or gland will also vary with the cross section of the ring, the type of operation, and the amount of the pressure used in the system. Some form of sealing method must be put in place to minimize the.
It is essential to select the highest quality fibre packing that will last. How does the steam turbine gland sealing system work. Packing is used in applications with sea water, oils, waste water and greases. Sealrite limited offer an extensive range of gland packing types with a vast variety of materials and constructions to suit a wide range of industry applications. Their high quality design and construction requires less pressure on the gland to form the seal, which leads to less wear on the equipment, less maintenance and most importantly, increased packing life span. When a pump operates, the liquid could leak out of the pump between the rotating shaft and the stationary pump casing. Gland packing costs are low in comparison to downtime costs that plants may incur from factors such as machinery wear and gland. For a packing gland this might not be important however to a mechanical seal it can be another adverse condition with which to cope.
In these heavyduty applications, the packing is often required to support the ram as well as maintaining a highpressure seal. Maximum capability, rotary gland packing, for an extreme range of duties, against virtually all chemicals and temperature conditions. A guide to gland packing, selection of gland packing. As turbine exhaust is connected to a condenser which is operated. Worn seal packing is far easier to repair than a damaged slurry pump. The most abrasion resistant of all our packing seals, these are made of ptfeimpregnated aramid fiber that has been saturated in a lubricant. The setting position of the seal is set by the cartridge design, but the. Curtisswright nuclear sealpro valve packing database and. Type vc5vc51 vulcan seals type vc5 is squarebraided from high. By design, the spiraltrac technology takes advantage of the existing rotational flow and directs particles away from the mechanical packing expelling them out of the stuffing box. Mechanical seal gland design problem solving products. Bitdefender is a global cybersecurity and antivirus software leader you can trust and rely on, protecting over 500 million systems in more than 150 countries. Topics include the functions of glands, bushing types, the shaftcentered gland, flush arrangements and more.
Pure ptfe fiber packing is a braided packing made of ptfe yarn without soaking any ptfe dispersion and lubrication but with greatly enhanced ability to seal high speed shafts with the addition of inactive and heatresisting a. Mechanical seal design operating principles classification application limits drive mechanisms loading devices mating ring types gland design gland functions bushing types shaftcentered gland piloted flush arrangements more on flush oring, seal design oring, seal design oring, seal failure psp oring sizes. Garlock packing is designed to give the user the greatest return on initial investment in terms of leakage control, service life, and dependable, costeffective product. Stuffing box design and installation of compression packings. The most important factor in designing a gland water system is to ensure the system is reliable and has sufficient pressure. Cixi city xinsheng seal factory develop and produce all kinds of sealing materials and products, our factory produce all kinds of seals, such as highstrength graphite gasket, ptfe gasket, graphite. Any increased tightening of the gland bolts will worsen the condition. The gland locates the seal axially and compresses the seal radially. Seal function the seal you require will usually be for the rod, ram, gland or piston and you may also require wipers or bearing strips. The braided packing is cut into rings, inserted into a stuffing box and compressed using a bolted gland. Equipment condition and designstuffing box finish, shaft finish, shaft runout and.
When compression packing fails, the consequences can be devastating. Attempts have been made by pump manufacturers to minimize this leakage through design, but the leakage wont be stopped entirely. For understanding the gland sealing system first we have to understand why it is required so there are two main reason. Control valve packing gland packing in control valve.
The gland at the rotating shaft of a centrifugal pump may be packed in a similar way and graphite grease used to accommodate continuous operation. Our quality control methods for material and manufacturing processes ensure that all seals leaving our factories are in a condition capable of giving a long and reliable service life. Curtisswrights sealpro is a webbased, valvepacking database and fluid leak management program that is able to design and manage configurations, track leaks and valve repair, and uses a system of future, installed, and history statuses to accurately maintain a standard revision process flow. The garlock compression packing facility is committed to supplying the highest quality engineered products to industry throughout the world. All squarebraided sealrite limited gland packing is made using the most advanced braiding machines and materials available to maximise packing service life and performance. Alton way, unit i centennial, colorado 80112 303 7582728.
Since the shaft rotates, preventing this leakage can be difficult. The following steps have been devised to ensure effective installation of packings on pumps and valves. Compression results take into account crosssectional. Gland packing costs are low in comparison to downtime costs that plants may incur from factors such as machinery wear and gland maintenance. For ac compressor mechanical seal is used as no leak is. Dimerpack 0011 applications for the sealing of installations and equipment in the chemical, pharmaceutica l, food processing, oil re. Parkers calculators not only address standard oring sizes, but allow users to custom design oring glands and seals specifically for their application. Kalsi seal gland guidelines kalsi seals handbook, chapter d5.
Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Aesseal packing displays an exceptional level of resilience and conformity of volume. If gland water pressure is too low, it will not be able to overcome backpressure from the pump and cause the slurry to backflow into the sleeve. The gland is the enclosed space defined by the housing groove and the rotary shaft. Earlier pump models used mechanical packing otherwise known as gland packing to seal the shaft.
The gland nut allows the packing material to be compressed to form a watertight seal and prevent water leaking up the shaft when the tap is turned on. Even when the seal ring isnt clamped, it is often axially supported inside a gland plate. Curtisswright nuclear sealpro valve packing database. Seal flush port the gland or seal housing in many seals contains a port for injecting liquid, either from the pump discharge or from an external source. For shafts of size 30 to 46 mm diameter the gland packing of size 10 mm is used.
Bitdefender is a global cybersecurity and antivirus. Apr 17, 2018 packing seals are removed and replaced much more often than mechanical seals, which causes considerable wear and tear to the pumps as they are disassembled and reassembled. Dimerpack 2210 applications packing is suitable for applicationswith steam, in high pressure pumps and. For shafts of size 16 to 28 mm diameter the gland packing of size 8 mm is used. But generally the following sizes of the gland packings are recommended for the different shaft sizes as follows. Having a circular cross section that functions as a seal, in both static and dynamic. Many packing failures are due to incorrect installation of the packing. Designing the parts of an application where orings will be applied is broadly termed oring groove design. Cut to size, the packing pieces are eased down the shaft to the neck ring.
Packing failure can cause pump damage, pump failure and unscheduled plant shutdowns, not to mention the cleanup effort. Mechanical seal vs gland packing linkedin slideshare. Therefore, it is of the utmost importance to select the highest quality modern fibre packing in an interbraided construction and optimized profile to provide the most resilient, longlasting packing sealing solution. Oct 17, 2016 sealing system for rotating shafts mechanical seals and packing 1. How can compression gland packing be applied in severe. Some form of sealing method must be put in place to minimize the leakage. Seal implementationrelated software kalsi engineering. A few millionths of an inch out of flatness will result in a leak. To avoid tearing or nicking, the use of oring lubrication is recommended while installing the oring into the dovetail gland. The cut ends are staggered to prevent leakage through them, the lantern ring is placed in position, the final three pieces of packing tamped in place by the gland plate and the work is done. Gland packing extensive range eastern seals uk ltd. The challenge has been to find the optimal design for existing pump geometries, speeds, fluid properties and equipment orientation that allows the build up of.
This presentation is made by mohamed elkeik on 17102016 email. What is the difference in using mechanical seal and gland. The setting position of the seal is set by the cartridge design, but the seal device need to not be screwed to the shaft till the gland plate is secured to the pump and any adjustments made to the shaft position. As turbine exhaust is connected to a condenser which is operated below atm pressure so there are chances of air ingres or va. The design of the groove where the oring sits plays a major role in how the oring performs its sealing role. Compression packing basics, what is compression packing, function of fluid sealing, structure, compression packing installation in pumps and valves. Now take the packing material and place it in the pump stuffing box. Parker recommends utilizing our design tools mobile inphorm and the oring selector design software to guide the user through the design and selection of an oring and corresponding seal gland. Aesseal offers a selected range of gland packing that have been specifically designed and manufactured to reduce plant operational and maintenance costs. A good valve design should have a fully open position back seat to enable the gland repacking with the valve in service. Gland packing designed to minimise maintenance costs. The classic gland seal packing is required to drip in operation to lubricate the shaft. Characteristics braided packing made of 100 % ramie, impregnated with graphite and tallow. If its leaking, think before tightening efficient plant.
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