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Sizing Semi-Metallic Gaskets When Replacing Soft Gaskets When replacing soft gaskets with semi-metallic gaskets, it's important to understand the sizing differences and considerations. The following guidelines provide suggested dimensions based on experience to help you choose the appropriate non-metallic gasket size to replace a soft gasket. These sizings are not mandatory but serve as useful recommendations. 1. When Flange Dimensions Are Provided If the customer provides the dimensions of the flange, the following guidelines can be used to determine the appropriate gasket size: Gasket Inner Diameter (I.D.) : The inner diameter of the gasket should be the bore size of the flange plus a minimum of 1/8". Gasket Outer Diameter (O.D.) : The outer diameter can be up to the bolt hole circle diameter minus one bolt hole diameter. This applies when the proposed gasket width corresponds to the standard width of semi-metallic gaskets, which is typically 1/2", 3/4...

  Comprendre l'Impact de la Température et de la Pression sur la Performance des Joints Une Analyse Approfondie de l'Influence des Conditions de Température et de Pression sur la Performance et la Durée de Vie de Divers Matériaux d'Étanchéité Dans le domaine de l'étanchéité des fluides industriels, comprendre comment la température et la pression influencent la performance des joints est crucial. Les joints sont conçus pour empêcher les fuites, garantissant que les fluides restent contenus dans un système. Cependant, les conditions dans lesquelles ils fonctionnent peuvent avoir un impact significatif sur leur efficacité et leur longévité. Voyons comment différentes conditions de température et de pression affectent la performance et la durée de vie des matériaux d'étanchéité couramment utilisés. Température : Le Facteur Chaleur   Les extrêmes de température peuvent grandement influencer la performance des joints. Les températures élevées et basses peuvent prov...

  Understanding the Impact of Temperature and Pressure on Seal Performance An In-depth Look at How Different Temperature and Pressure Conditions Affect the Performance and Lifespan of Various Sealing Materials In the world of industrial fluid sealing, understanding how temperature and pressure impact seal performance is crucial. Seals are designed to prevent leakage, ensuring that fluids remain contained within a system. However, the conditions under which they operate can significantly influence their effectiveness and longevity. Let's delve into how different temperature and pressure conditions affect the performance and lifespan of commonly used sealing materials. Temperature: The Heat Factor Temperature extremes can greatly influence seal performance. Both high and low temperatures can cause material deformation, chemical breakdown, and loss of elasticity, leading to seal failure. Here's how different materials react: 1. Elastomers: High Temperatures: Elastomers lik...

  Transformers are an essential part of the electrical power distribution grid. Transformer gaskets’ materials are critical for their performance and longevity. Hence, this requires the best selection of sealing materials as leakage can lead to oil contamination of surrounding environment, damaging insulation materials and significantly reducing the life of a transformer. Proper gasket material will help maintain the transformer’s dielectric strength, prevent oxygen, nitrogen and/or moisture leaks, prevent oil contamination and more… Below are some options to consider for proper gasket material selection: Cork with Nitrile binder : traditional material used for decades. Easy to compress in place, fair weather and oil resistance. Low cost Nitrile rubber (NBR) : for general purposes with operating temperature between -30°C to 100°C. Low cost, easily available Fluoroelastomer ( V iton ® B, FKM) rubber : application for higher temperatures to 200°C. Expensi...

Why use spiral wound gaskets ? Lotfi Grine, Eng. – Product Specialist at Robco Many types of industrial gaskets can be found in the field. Yet, the 2 most popular types of gaskets found are Spiral Wound Gaskets (SWG) and gaskets cut from calendered sheets. SWG are manufactured by spirally winding together a ‘V’ shaped metallic strip and a soft filler, generally g raphite. Calend e red S heet G askets are cut from sheets, which are manufactured by mix i ng, pressing and curing a composite of high temperature and chemically-resistant fibers, fillers and elastomers . Although in some cases, both type of gaskets can be used interchangeably, i t’s essential to choose the right gasket according to the application details. Why would you choose spiral wound gaskets? Benefits of Spiral Wound Gaskets SWG are capable of handling a significant part of the oil and gas industry applications . Below, we list some of advantages of spiral wound gaskets, so you can make a more informed decisi...

  Compression contre charge : que devez-vous utiliser ? Lotfi Grine, ing. – Spécialiste de produit chez Robco  Une question courante concernant l'étanchéité avec des matériaux de joint plat est le pourcentage de compression approprié ou/et la quantité de charge nécessaire pour les comprimer. Il s'agit d'un paramètre de conception critique. Ces deux paramètres peuvent affecter le nombre, le type, la taille et l'espacement des fixations telles que les boulons pour empêcher la déviation du boîtier, la rotation de la bride et les fuites ultérieures. Étant donné que plusieurs matériaux de joint sont constitués d'un composite, comme les matériaux de joint semi-métalliques ou joint aux feuilles calandré, c'est le niveau de couple (charge) plutôt que le niveau de compression du joint exprimé en pourcentage qui compte. Ce niveau de couple sera choisi en fonction de différents paramètres tels que la qualité des boulons, le type de bride, la contrainte d'étanchéité ma...

  Compression versus Load: what should you use? Lotfi Grine, Eng. – Product Specialist at Robco One common question concerning sealing tightness with flat gasket materials is the proper compression percentage or/ and the amount of force needed to compress them. This is a critical design parameter. These two parameters can affect the number, type, size and spacing of attachments like bolts to prevent housing deflection, flange rotation and subsequent leakage. Because several gasket materials consist in a composite, like semi-metallic or compressed sheet gasket materials, it is the level of torque (load), rather than the level of gasket compression expressed in percentage that matters. T his level of torque will be chosen according to different parameters like bolts grade, flange type, maximum and minimum sealing stress, etc.  For Klinger compress sheets and gaskets, Robco uses KLINGERexpert software to assist users for improved scientific calculations of bolt torque requi...

Can flanges of various shapes be used together? Lotfi Grine, Eng. – Product Specialist at Robco Flat face flanges should never be bolted to a raised face flange. ASME B31.1 states that when connecting flat face cast iron flanges to carbon steel flanges, the raised face of the carbon steel flange must be removed and a full gasket is required. This is to prevent the cast iron flange (a thin, brittle material) from hanging in the space caused by the raised face of the carbon steel flange.   But there's a solution: if the flanges cannot be remanufactured, add a center ring between the raised face flange and the flat face flange. This ring carries one side with a raised face and another side with a flat face, and uses two gaskets. (Preferably a Maxiprofile type for the raised face).

  Peut-on utiliser ensemble des brides de diverses formes ?   Lotfi Grine, Eng. – Spécialiste de produit chez Robco Les brides à face plate (flat face) ne doivent jamais être boulonnées à une bride à face surélevée (raised face). L'ASME B31.1 indique que lors du raccordement de brides en fonte à face plate à des brides en acier carbone, la face surélevée de la bride en acier carbone doit être retirée et qu'un joint d'étanchéité complet est requis. Cela permet d'éviter que la bride en fonte (un matériel fin et cassant) ne soit suspendue dans l'espace provoqué par la face surélevée de la bride en acier carbone.   Mais il existe une solution :   Si les brides ne peuvent être réusinées, ajouter un anneau central entre la bride à face surélevée et la bride à face plate. Cet anneau porte un côté avec une face surélevée et un autre côté avec une face plane, et utilisent deux joints d'étanchéité, préférablement de type Maxiprofile.

  ASME PCC1-2019 : technical notes about sealing performance Lotfi Grine, Eng. – Product Specialist at Robco   In the following technical notes, you will find valuable technical extracts from the ASME PCC1 2019 ( bolted flange joint assembly (BFJA) guidelines) to help better understand sealing behaviour and produce a positive seal. - Calculating Target Torque Values are based on the root area. The root areas are based on coarse-thread series for sizes 1 in. and smaller with 8-pitch thread series for sizes 1 1/8  in. and larger (Section H). - The major long-term value of coated bolts is to protect against corrosion of the exposed threads and to minimize break-out and nut-removal torque, thereby promoting ease of joint disassembly (Section 7). - Section VIII, Division 1 of the ASME Boiler and Pressure Vessel Code requires that nuts engage the threads for the full depth of the nut (Section 8.2).   - Start-up re-torque is performed when the temperature of ...

  Pressure capability guidelines: There are many gaskets materials type, and the pressure ability to withstand for each materials type is different. It starts from low pressure for soft gasket material up to high pressure for metallic and semi-metallic gaskets. So, according to the pressure level high or low we need choose the right gasket material to create a reliable seal. The chart below provides a guide to the suitability of our materials in standard ANSI flanges. Note: It should be noted that the ability to withstand assembly load is also dependent on the temperature of the application, and therefore gasket selection must be cheked with the pressure/temperature graphs given for each material. We use Klinger reference of material styles because those are the ones we know best. Materials Class 150 (20 bar) Class 300 (50 bar) Class 600 (100 bar) Class 900 (155 bar) Class 1500 (260 bar) Class 2500 (4...