gasketing
- February 19, 2024
Gallagher Fluid Seals partners with the world's top gasket suppliers. Our strong partnerships allow us to provide you with the best gasketing options, from PTFE, Metallic, and Compressed Non-Asbestos
Choosing the Correct Semi-Metallic Gasket
There are many variations of semi-metallic gasket available in today's market. The combination of metal and a soft gasket material merges the sealing ability of the soft material with the structural integrity of the metal.
The most common styles of semi-metallic gasket include spiral wound gaskets, corrugated, jacketed, and kammprofile gaskets.
Pumps & Systems magazine outlined the proper way to select a semi-metallic gasket.
Gasket selection suggestions
Choosing a gasket depends on a few different factors: operating conditions, fluid compatibility, mechanical features of the joint
- May 18, 2023
The Best Gasket Types for Increased Heat
Under pressure? Absolutely. The increasingly high temperatures and harsh conditions to which gaskets are exposed makes selecting the right gasket all the more important.
In industries such as chemical processing, hydrocarbon refining, and power generation, leakage from extreme temperature process streams can result in loss of efficiency and production as well as adverse environmental impacts and compromised employee safety. One of the most commonly used sealing products in systems subject to high pressures and temperatures is a spiral-wound gasket. These gaskets typically consist of filler and winding materials selected on the basis of application requirements and end-user preference. Proper selection of these materials is critical to achieving the desired performance in all applications.
Material Selection for High Temperature Gasketing
Sealing at temperatures above 850 ºF (454 ºC) is particularly challenging because of the limited number of filler materials that can resist thermal degradation at extreme temperatures – these temperatures affect both the sealing material and metal components. For instance, the yield strength of fasteners decreases as the temperature is increased. In addition certain chemicals can become more volatile and aggressive in high-temperature reaction processes.
The two most common filler materials in spiral-wound gaskets are graphite (can withstand temperatures up to 850 ºF) and polytetrafluoroethylene (PTFE; tolerance up to 500 ºF). Other filler materials are used mainly for their thermal insulating properties, not for sealability; these include mica, exfoliated mica, and ceramics. While graphite and PTFE perform satisfactorily in terms of temperature and chemical resistance, they have limitations. Graphite is not compatible with heavily oxidizing media at any temperature, nor can it withstand continuous operating temperatures above 850 ºF. Beyond 850 ºF, volume loss through oxidation becomes excessive and sealing effectiveness is compromised.
Many high-temperature systems, such as exhaust manifolds and flanged piping connections in exhaust systems, are oxidizing. Other services are oxidizing because of the operating temperature and media involved.
- January 18, 2023
Sealing Sense for Gaskets
Safety is a concern at any industrial site. An Occupational Safety and Health Administration compliance specialist has stated that safety should be more than a priority: “Priorities in an organization can and usually do change. Safety and health need to be a core value of the organization.”1
Safety can be a case of values versus priorities. When it comes to sealing devices, perceived dangers sometimes are overlooked.
The case of an explosion at a refinery in Anacortes, Washington, shows how deadly accidents can occur when safety risks
- August 09, 2022
When PTFE (polytetrafluorethylene) was developed in 1938, its importance to industrial sealing was quickly recognized because of its tremendous chemical resistance.
While use of PTFE as a gasket material increased in industrial applications, complaints about certain properties surfaced: skive marks made initial sealing difficult, cold flow caused leakage and premature failure, and temperature/pressure cycling was a problem.
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo. - February 10, 2021
This blog will discuss the differences between ASME flanges and AWWA flanges and the gaskets associated with each.
ASME flanges are the most widely used and specified flanges throughout industry in North America. Flange sizes ½” through 24” fall under ASME B16.5 and flange sizes 26” through 60” fall under ASME B16.47. Within ASME B16.47 there are series A and series B flanges, with the noticeable differences in most cases being the bolt size and/or bolt quantity.
- August 05, 2020
So you spend hundreds or even thousands of dollars every year on sealing solutions, like gaskets. But did you know that the way you store your gaskets could affect the effectiveness or life span of your gaskets? In this blog, we offer some tips for gasket storage and shelf life which, if followed, can help ensure that your gaskets are always ready for service.
Gasket Storage and Shelf Life: General Storage Principles
Rubber gaskets should always be stored in a cool location which is free from excessive humidity, direct sunlight, and the presence of chemical vapours or fumes. The storage location should ideally be indoors and free from exposure to the elements or inclement weather. If the storage guidelines given below are followed, rubber gaskets or gasketed components have the following expected shelf life:
Tips for Gasket Storage and Shelf Life
Tip #1: Limit exposure to light
Sunlight and strong artificial light can degrade some gasket materials. For this reason, rubber gaskets should be stored in cartons or opaque bags which prevent direct exposure to light.
Tip #2: Maintain relative humidity levels
Very moist or excessively dry conditions in a storage location should be avoided. Relative humidity levels below 75% are recommended for most rubber gaskets. Similarly, very low humidity levels which can cause some materials to dry out and become brittle should also be avoided.
- May 06, 2020
In addition to KLINGER's complete Sheet Gasketing Product Line which now includes the new major change in construction of their PTFE Products TC 1003, TC 1005, and TC1006, they have added a great new product to cover additional applications during day-to-day operation.
The KLINGER SAVER
A new product we are featuring on our blog is THE KLINGER-SAVER - a tool to eliminate hand injuries.Bolt tightening or loosening activities, or using slug wrenches and hammers can often the cause of serious finger or hand injuries.
The KLINGER-SAVER is a safety device that allows an assembly technician to remove his hand from the potential danger of being struck by the hammer.
How The KLINGER-SAVER Works
The wrench - April 16, 2019
The Dreaded Gasket Blowout Call
Have you ever received the dreaded 2 a.m. call from plant staff saying that things are at a standstill – production is down?
You arrive at the plant, walk through the parking lot, coffee in hand, and head to the locker room. When you come out on to the plant floor, there are several people staring at you with a look of panic on their faces as steam or process chemical sprays from a pipe flange.
Prognosis……gasket blowout.
You think to yourself “didn’t we just replace that gasket?”, or perhaps “we should have replaced it during the last shutdown but chose not to because of time constraints or cost cutting.”
If this scenario is new to you, you are lucky and you can go back to sleep… the 2 a.m. call was a wrong number. If it’s not new to you, this means you are most likely a Plant Supervisor, Maintenance Manager or Plant Personnel in some capacity.
Roll up your sleeves, grab your torque wrench and let’s get to work!
Gasket Lifespan
If I had a nickel for every time someone asked me, “How long will my gasket last?” I would be a rich man. As you can probably guess, “How long will my gasket last?” is a loaded question to which the practical, factual, and political answer is… an Application Engineer’s nightmare!
A gasket may last 5 years, or it could last 20 years. I cannot give you an exact date or lifespan of a gasket; however I can give you some insight into factors that will give your gasket the best chance at a long and prosperous life between the flanges.
- March 14, 2019
A newly developed gasket tape made by Gore - of expanded polytetrafluorethylene (ePTFE) is specifically designed to address the challenges of creating reliable seals in large glass-lined steel equipment.
Equipment made of glass-lined steel is used when manufacturing or processing aggressive chemicals such as aniline derivatives and sulphuric or hydrochloric acid. The Achilles heel of such systems is the gaskets needed to seal the joints between components. Exposure to aggressive media causes the seals to degrade overtime, resulting in damage to equipment and posing a health risk to operators. Replacing the seals costs a great deal of time and effort, with a corresponding drop in production output.
A newly developed gasket tape made of ePTFE (expanded polytetrafluorethylene) is specifically designed to address the challenges of creating reliable seals in large glass-lined steel equipment.
Operators of chemical plants choose sealing materials according to a wide range of criteria such as process medium, flange type, sealing performance, pressure and heat resistance, cost and longevity. Other important selection criteria include time required for installation and inventory management. And, of course, a plant operations prior gasket experience weighs in as well. Gaskets for glass-lined-steel equipment are safety-relevant parts because their failure can endanger human lives and/or harm the environment, but they are often treated for administrative purposes as C-class items, that is, parts of minor significance.
This classification doesn’t reflect the true importance of these sealants. There is a need for more explicit regulations to supplement the general legislation pertaining to occupational health and safety and the handling of hazardous substances. The introduction of a European-wide regulatory basis for establishing detailed, standard processes would be welcome, for instance with respect to approval procedures and safety. As things stand today, companies are obliged to find their own compromise between varying sets of requirements. These include compliance with EU-wide and national directives concerning environmental protection and occupational health and safety. At the same time, companies are making efforts to augment the reliability of their products, simplify inventory management and installation processes, and reduce downtime and overall costs. An added factor in both cases is specific process requirements with respect to temperature, pressure and media.
SEALING CHALLENGES
One particular challenge is that of choosing the right sealant for glass-lined steel systems, because these involve the use of aggressive media such as aniline derivatives and sulphuric or hydrochloric acid under demanding conditions. Glass-lined steel presents the advantage of being highly resistant to corrosive and/or abrasive media. Other characteristic features of this material are its smooth surface, which is easy to clean due to its low adhesion properties, and its biologic and catalytic inert behaviour. Nonetheless, it can be difficult to achieve reliable seals in glass-lined steel equipment. This is because the glass lining is more brittle than the metal, and can therefore split or splinter if handled incorrectly. As a result, the gasket load that can be applied to the seal is lower than that for an all-steel flange. Consequently, care must be taken to limit the pressure applied when installing gaskets between interconnecting parts of the system.
Another problem is that of achieving a reliable seal if the flange surface is uneven or has surface deviations. Once the glass lining has fused, its surface cannot be reworked. The challenges posed by these characteristics of glass-lined steel, combined with the exposure to aggressive chemicals and high temperatures, must be met by the chosen sealant. In practice, these difficult conditions often lead to premature sealing failure and a greater risk of corrosion. The further consequences of sealing failure include leaks and uncontrolled emissions, damage to equipment, high replacement and repair costs, production losses, unplanned maintenance and downtime, and potential risks to employees’ health and safety.
- October 24, 2017
When sealing raised or flat face flanges, there are two choices of gasket shape: ring-type or full-face. Each has its own advantages, so you should know which will best suit your application before ordering and installing. First, let's discuss the types of flanges in which gaskets are installed.
Flange Faces
Different types of flange faces are used as the contact surface to seat the sealing gasket materials. ASME B16.5 and B16.47 define various types of flange facings, including the raised face, the large male and female facings which have identical dimensions to provide a relatively large contact area.
Raised Face (RF) Flanges
The Raised Face flange is the most common type used in process plant applications, and is easily to identify. It is referred to as a raised face because the gasket surfaces are raised above the bolting circle face. This face type allows the use of a wide combination of gasket designs, including flat ring sheet types and metallic composites such as spiral wound and double jacketed types.
The purpose of a RF flange is to concentrate more pressure on a smaller gasket area and thereby increase the pressure containment capability of the joint. Diameter and height are in ASME B16.5 defined, by pressure class and diameter. Pressure rating of the flange determines the height of the raised face.