Flange length the total length of the arc or line on the flange of the wheel profile, starting. Suggested methods and guidelines for torquing and bolting flange joints 1 bring mating flanges into contact and install bolts, torquing nuts finger tight. How to identify and repair flange face corrosion and the types of machines available to help. Closer tolerances on weld end preparations than stated in figure 1 and figure 2, may be specified in the relevant welding specification for the material in question, and shown on the fabrication isometrics. Pipe full face flangetyte gaskets bro024 revised 03. Topics such as proper bolt and gasket selection, flange face arrangements, alignment during installation, boltup patterns and the relationship between applied bolt torque and. Garlock gasketing products the demands of modern applications make the choice of the right sealing product an important consideration, both in the design of new equipment and in choosing the new products which will replace those no longer suitable.
These objects may include the bristles of a wire brush or a tool, such as a chisel. Asme raised face is tightened by installing a flat gasket. To machine the flange face sealing surface, a flange facing machine is the ideal product to get the job done quickly and accurately. With flange face the form and implementation of the side of a flens are meant, where a sealing ring or gasket will be placed. Flat face flange enquiry typically these flanges are used on pump facings or on fiberglass flanges where the torque of compressing the gasket will damage the flange body. Proven for over 10 years, the belzona flange face forming technology eliminates the need for conventional cut and weld repair methods involving hot. May 30, 2017 frequently, this type damage is created by a sharp object dragging across the flange face. Process vessel and pipe spool flange face damage becomes apparent only when adjacent pipe spools are removed, or if a flange starts leaking either in service or during a leak test. The use of bolts which are too long and bottom out can crack or distort the body, causing permanent valve damage. There are four basic types of repair that can be considered. The flange face is the surface area that hosts the gasket.
Gasket selection using the gasket design factors as per en. Figure 1 awwa c207 flat face flange figure 2 full face and ring style gaskets drawing of flat face slipon ring flange showing detail of fillet welding to pipe flat or full face gasket bolts pass through the. The technique detects flange id bore and raised face wall losses. This document references allowances for flange face flatness, flange face imperfection tolerances and allowable defect depth vs. Strain sensitive equipment with flange connections 10 gaskets 11 bolting 11 pipe support 12 global tolerances, installation 12. Page, in estimators piping manhour manual fifth edition, 1999. How to manage and understand flange face damage triangle. Flange clearance wheel flange clearance is the wheel lateral shift limit relative to rail prior to wheel climb. Dec 01, 2015 once the flange face is damaged, the flange is no longer sealable by a gasket and requires replacement or repair. Asme pcc120 appendix d guidelines for allowable gasket contact surface flatness and defect depth d1 flange face flatness tolerances existing industry flatness tolerance limits1 do not include an assessment of the ability of the gasket to tolerate imperfections. Pdf piping joint handbook danny ferdiansyah academia. How to protect serration of flanges during hot dip galvanization. Rtj grooves must be kept clean, corrosion free and undamaged. Flat face ff the flat face flange has a gasket surface in the same plane as the bolting circle face.
Guidelines for safe seal usage, flanges and gaskets. In an attempt to bridge the gap between the simplest conventional single element approach and the more comprehensive, we began a study designed to provide a viable phased array flange face inspection solution that is highly portable, and simple to use for an experienced phased array inspector. Acceptance criteria for scratches and indentations in plastic. Durlon torque values can be found on pages 4953 of the durlon gasket manual. Angularity tolerances across the face of flanges, weld end preparation and rotation of flanges shall be as stated in figure 1 and figure 2.
Crevice corrosion has long been the achilles heel of stainless steel flange equipment in seawater service, where corrosive materials concentrate between. The following results from fea analysis and testing on a purposebuilt flange test rig clearly demonstrate that even a perfect rtj correctly seated and assembled in a flange and boltedup to the correct bolt tension will face the same seating stress issues with consequent risk of leakage in high temperature pressure applications. Abstract the assembly of flanges, seals, and pipes are used to carry cryogenic fluid from a storage tank to the vehicle at. The facing on the rf flange has a concentric or a spiral phonographic groove with a controlled surface finish. The ultrasound angles can be adjusted to fit the specific flange geometry and the multiple ultrasound angles used to optimize data displays of corrosion andor erosion. A big benefit in using pcc1 when sealing damaged flange faces is that it. If galvanising is applicable in to your project flanges than specific requirements of flange seration roughnes will not be there in specs and piping class. Flange tyte ii full face gasket 2016 edition reised 0. Angularity tolerances across the face of flanges, weld end preparation and. I have used different criteria for flange face gasket surface damage evaluation at several different refineries throughout the u.
Flange climb derailment criteria and wheelrail profile. Corrosion of gasket seating surface of raised face procedure. Welding can be permitted for flange faceserration damage. Flanges with different faces require different gaskets and shall never be mated to prevent leakage of the joint. The series 39 valve contains 2 gaskets between the. Example imperfections is from outer to inner side of raise face with a depth of. When replacing gasket material in a bfja or performing maintenance, pay attention to the flange face. Applications using flat face flanges are frequently those in which the mating flange or flanged fitting is made from a casting. Flange serration face damage asme mechanical code issues. Sealing is achieved by compressing a flat, soft, or semimetallic gasket between mating flanges in contact with the raised face portion of the.
In both cases, the equipments integrity has been lost. Does anyone have any literature or guidelines they would like to share on acceptance criteria of gasket surfaces. Potential causes of leaks in a flange joint include. The belzona flange face forming kit is a unique repair kit developed to aid the flange face forming technology in combating the common problems with mating surfaces of flanged joints such as heat distortion, corrosion and erosion. Removing the corroded flange and welding a new one. Dear hamid, galvanised flanges mostly used in utility services not in hydrocarbon service where leak and leakage is catastrophic. Mirage machines manufacture a wide range of machine options, including models that can be. Flange back clearance the distance between the flange back face of the wheel and the contact face of the restraining rail. When inspecting the raised flange face area, encoded magnetic scanners direct sound from the od of the flange between the bolt holes. We have a wnrf flange of dia 20 of which the serration face is damaged approximately 3mm depth and length 60mm due to the improper handling.
A serrated finish, either concentric or spiral, is required with 30 to 55 grooves per inch and a resultant roughness between 125 and 500 micro inches. The process of flange facing involves the machining of flange mating surfaces on pipe and vessel connectors to produce a tight, leakproof seal when assembled. The recommended manual flange bolt tightening procedure is as follows. The rings size and material quality is marked on the ring. The new elongated bulb seal covers a larger section of the pipeflange interface, providing a.
Asme addressed this issue in its standard, guidelines for. Types of flange facesraised face, flat face, ringtype joint, maleandfemale, tongueandgroove. Only use flange bolts of the correct length so that the bolts do not bottom out in tapped holes. Rf, ff, rtj flange face and finish projectmaterials. Flat face flanges are never to be bolted to a raised face flange. Inservice piping 7 what to inspect api 570 doesnt cover everything. Sc oceaneering international, asset integrity unit 5, castell close, enterprise park llansamlet, swansea sa7 9fh, uk abstract there is a growing interest within the petrochemical and associated industries for.
Irregularities in the surface can impact upon the effectiveness of the gaskets ability to close potential leak paths and the friction values needed to keep the gasket. Share your knowledge on serration damage on flange face. Flange faces to be bolted up must be parallel, free from damage, and have a. Sep 11, 2016 tested joints may leak in service due to temperature variations across the flange face which are not seen during testing. The new elongated bulb seal covers a larger section of the pipe flange interface, providing a. Pdf leakage criteria through a nongasketed flange pipe joint. Reprinted from asme pcc12010, by permission of asme. An overview of asme, esf and fsa guidelines the flange surface finish for the sealing area is commonly represented by the symbol ra. This update identifies some of the typical damage that occurs. Repair of the flange face the corrosive action of chemicals, crevice corrosion, galvanic corrosion and high pressure. The examination is performed by placing the transducer on the flange between the bolt holes see figure 2 and scanning toward the bore of the flange. Flangetyte ii full face gasket 2016 edition reised 0. What are the permissible imperfections or acceptance criteria in flange facing finish for raised face flange.
Acceptance criteria for scratches and indentations in. The flange face, particularly the seating area, shall be visually examined for cleanliness and ensure no damage such as scratches to exist. Nsf certified to ansinsf 61 full face flange tyte gasket u. Gougesthese are wide and elongated with blunt, rounded bottoms and are created by a dull object dragging across the flange face.
This catalog provides some typical examples of appropriate. The surface finish of the faces is specified in the flange standards quoted previously. Suggested methods and guidelines for torquing and bolting. Successful sealing of problem flanges in high temperature. A combined effort, to investigate and identify the risks of mechanical damage to pipes made of the. Flat face ff typically these flanges are used on pump facings or on fiberglass flanges where the torque of compressing the gasket will damage the flange body. It is called raised face because the gasket is raised 116 and 14 above the bolt circle face. Sharp instruments can damage the flange face and cause possible leakage. How to protect serration of flanges during hot dip. The raised face is the most commonly used facing employed for steel flanges.
Jan 10, 2016 raised face rf the raised face is the most common used flange face. Can any one recommend me the correct procedure to rectify the damage and whether the code asme b16. Sealing worn flange faces triangle fluid controls ltd. Site machining of the seal face ring groove within the flange tolerance. Donts a when cleaning a flange face, never use a tool which may damage the surface finish. Orifice flanges are not covered by this standard, but all ansi flange tolerances, where applicable, apply to all coastal orifice flange diminisions except the bore. The parties in the plastic pipe market have sought acceptance criteria for scratches and indentations in different types of pipes and for different types of pipe duties. Irisndt inspects inservice raised face flanges with phased array ultrasonic testing paut. Nov 18, 2002 i have used different criteria for flange face gasket surface damage evaluation at several different refineries throughout the u. Note any visual defects or damage marks, scratches, dings or anything that changes the serrations on the flange face that can affect the flange s ability to bite into gasket material. What changes does this bring for the operators of plants and what criteria should be considered in the selection of gaskets using the characteristic as per en 555. Selective pulse echo, contact angle beam ultrasonic techniques are used to examine the flange face gasket seating area.
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