Irisndt inspects inservice raised face flanges with phased array ultrasonic testing paut. 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. Flange tyte ii full face gasket 2016 edition reised 0. Suggested methods and guidelines for torquing and bolting flange joints 1 bring mating flanges into contact and install bolts, torquing nuts finger tight. Durlon torque values can be found on pages 4953 of the durlon gasket manual. Guidelines for safe seal usage, flanges and gaskets. Reprinted from asme pcc12010, by permission of asme. 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. This update identifies some of the typical damage that occurs.
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. Site machining of the seal face ring groove within the flange tolerance. Flange clearance wheel flange clearance is the wheel lateral shift limit relative to rail prior to wheel climb. 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. In both cases, the equipments integrity has been lost. These objects may include the bristles of a wire brush or a tool, such as a chisel. The new elongated bulb seal covers a larger section of the pipe flange interface, providing a. 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. When inspecting the raised flange face area, encoded magnetic scanners direct sound from the od of the flange between the bolt holes.
Flange faces to be bolted up must be parallel, free from damage, and have a. 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. 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. Corrosion of gasket seating surface of raised face procedure.
Sharp instruments can damage the flange face and cause possible leakage. Pdf leakage criteria through a nongasketed flange pipe joint. Nsf certified to ansinsf 61 full face flange tyte gasket u. 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 inspection of crevice corrosion in flange joints using manual phased array stuart paul kenny m. What are the permissible imperfections or acceptance criteria in flange facing finish for raised face flange. Welding can be permitted for flange faceserration damage. 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. Pdf piping joint handbook danny ferdiansyah academia.
Pdf for bolted flanged pipe joints, it is commonly believed that there must be a. Rtj grooves must be kept clean, corrosion free and undamaged. Potential causes of leaks in a flange joint include. Mirage machines manufacture a wide range of machine options, including models that can be. Acceptance criteria for scratches and indentations in plastic. Page, in estimators piping manhour manual fifth edition, 1999. Gougesthese are wide and elongated with blunt, rounded bottoms and are created by a dull object dragging across the flange face. 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. Sealing worn flange faces triangle fluid controls ltd. It is called raised face because the gasket is raised 116 and 14 above the bolt circle face. Gasket selection using the gasket design factors as per en.
Flat face flanges are never to be bolted to a raised face flange. The raised face is the most commonly used facing employed for steel flanges. The recommended manual flange bolt tightening procedure is as follows. When replacing gasket material in a bfja or performing maintenance, pay attention to the flange face. How to identify and repair flange face corrosion and the types of machines available to help. Topics such as proper bolt and gasket selection, flange face arrangements, alignment during installation, boltup patterns and the relationship between applied bolt torque and. Inservice piping 7 what to inspect api 570 doesnt cover everything. Suggested methods and guidelines for torquing and bolting. Angularity tolerances across the face of flanges, weld end preparation and rotation of flanges shall be as stated in figure 1 and figure 2. Repair of the flange face the corrosive action of chemicals, crevice corrosion, galvanic corrosion and high pressure. With flange face the form and implementation of the side of a flens are meant, where a sealing ring or gasket will be placed. Share your knowledge on serration damage on flange face. Flange length the total length of the arc or line on the flange of the wheel profile, starting. Flange serration face damage asme mechanical code issues.
The new elongated bulb seal covers a larger section of the pipeflange interface, providing a. How to protect serration of flanges during hot dip. Flat face ff the flat face flange has a gasket surface in the same plane as the bolting circle face. The series 39 valve contains 2 gaskets between the. To machine the flange face sealing surface, a flange facing machine is the ideal product to get the job done quickly and accurately. 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. Example imperfections is from outer to inner side of raise face with a depth of. 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. May 30, 2017 frequently, this type damage is created by a sharp object dragging across the flange face. 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. The facing on the rf flange has a concentric or a spiral phonographic groove with a controlled surface finish. Flange back clearance the distance between the flange back face of the wheel and the contact face of the restraining rail.
Removing the corroded flange and welding a new one. Nov 18, 2002 i have used different criteria for flange face gasket surface damage evaluation at several different refineries throughout the u. The surface finish of the faces is specified in the flange standards quoted previously. Strain sensitive equipment with flange connections 10 gaskets 11 bolting 11 pipe support 12 global tolerances, installation 12.
How to manage and understand flange face damage triangle. 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. The use of bolts which are too long and bottom out can crack or distort the body, causing permanent valve damage. Pipe full face flangetyte gaskets bro024 revised 03. The flange face is the surface area that hosts the gasket. This document references allowances for flange face flatness, flange face imperfection tolerances and allowable defect depth vs. Proven for over 10 years, the belzona flange face forming technology eliminates the need for conventional cut and weld repair methods involving hot. 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. 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 flange facings are machine finished to ansiasme b16. I have used different criteria for flange face gasket surface damage evaluation at several different refineries throughout the u. A big benefit in using pcc1 when sealing damaged flange faces is that it. Flanges with different faces require different gaskets and shall never be mated to prevent leakage of the joint.
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. The packaging and stacking of castings must be arranged so as to prevent any contact or shifting of contents, which may damage castings. Dec 01, 2015 once the flange face is damaged, the flange is no longer sealable by a gasket and requires replacement or repair. Asme raised face is tightened by installing a flat gasket. Abstract the assembly of flanges, seals, and pipes are used to carry cryogenic fluid from a storage tank to the vehicle at. 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. 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. Successful sealing of problem flanges in high temperature. Applications using flat face flanges are frequently those in which the mating flange or flanged fitting is made from a casting. Acceptance criteria for scratches and indentations in. The rings size and material quality is marked on the ring.
Does anyone have any literature or guidelines they would like to share on acceptance criteria of gasket surfaces. 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. Angularity tolerances across the face of flanges, weld end preparation and. Flangetyte ii full face gasket 2016 edition reised 0. Only use flange bolts of the correct length so that the bolts do not bottom out in tapped holes.
An overview of asme, esf and fsa guidelines the flange surface finish for the sealing area is commonly represented by the symbol ra. Types of flange facesraised face, flat face, ringtype joint, maleandfemale, tongueandgroove. Can any one recommend me the correct procedure to rectify the damage and whether the code asme b16. A combined effort, to investigate and identify the risks of mechanical damage to pipes made of the. The technique detects flange id bore and raised face wall losses. Sealing is achieved by compressing a flat, soft, or semimetallic gasket between mating flanges in contact with the raised face portion of the. 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. Crevice corrosion has long been the achilles heel of stainless steel flange equipment in seawater service, where corrosive materials concentrate between. How to protect serration of flanges during hot dip galvanization. Jan 10, 2016 raised face rf the raised face is the most common used flange face.
Dear hamid, galvanised flanges mostly used in utility services not in hydrocarbon service where leak and leakage is catastrophic. Flange climb derailment criteria and wheelrail profile. 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. There are four basic types of repair that can be considered. The flange face, particularly the seating area, shall be visually examined for cleanliness and ensure no damage such as scratches to exist.
Asme addressed this issue in its standard, guidelines for. Rf, ff, rtj flange face and finish projectmaterials. Pipe 2017 edition p 3 the full face flangetyte gasket is a high performance gasket for flanged joint piping systems. Donts a when cleaning a flange face, never use a tool which may damage the surface finish. Selective pulse echo, contact angle beam ultrasonic techniques are used to examine the flange face gasket seating area.
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