Why don’t my PTFE gaskets seal FRP, plastic and other light load flanges?
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Top Seals Articles
Find a reliable dry gas seal system for any application.
First of Six Parts
Follow the major developments in seal technology
This month's "Sealing Sense" was prepared by FSA member Larry Sheffield.
Proper safety precautions for selecting, installing and maintaining seal systems
The next generation of materials where pumps meet mechanical seals may already be here in polymeric composites. The pump and mechanical seal industries just need to recognize, define and standardize these materials to realize their benefits.
ePTFE /Graphite packing tolerates a wide range of service conditions and has the capabilities inherent in PTFE while overcoming limitations of low thermal conductivity. These characteristics of ePTFE enable standardization of packing to simplify operations and improve productivity in many cases.
The oil and gas market has remained remarkably stable recently, bolstered by the high price of oil and strong worldwide demand. With refining capacity finite and political unrest in major oil producing countries such as Venezuela, Angola and Iran, the price may rise even higher.
In hydraulic cylinders, used in everything from precise positioning equipment in machine tools to heavy earth moving machinery in the toughest working environments, the requirements for sealing are varied and difficult.
The research and understanding of other's experiences, specifications and financing related to the decision can make the difference between a great experience and an expensive disappointment.
Latest Seals Articles
Why don’t my PTFE gaskets seal FRP, plastic and other light load flanges?
Find a reliable dry gas seal system for any application.
First of Six Parts
Follow the major developments in seal technology
This month's "Sealing Sense" was prepared by FSA member Larry Sheffield.
Proper safety precautions for selecting, installing and maintaining seal systems
Manufacturers of braided packings are often asked to simply supply "A PTFE packing." Though this may seem a straightforward request, it generates questions that must be answered to ensure the correct PTFE packing for the application. A clear understanding of the differences between the various forms of PTFE braided packing will enable a selection of reliable sealing for the pump or valve.
These graphite-loaded silicon carbide materials have been around for several years, and new applications are regularly identified. Initially, they were developed to address the highest P-V applications, with a focus on the highest pressures.
Multiphase pumping applications, also referred to as tri-phase, have been growing during the past several years, especially due to increased oil drilling activity. For example, in Canada the drilling and refining of tar sands often requires the use of multiphase pumps since the fluid stream can be a mixture of gas, liquids and solids.
A discussion of current compression packing technology will help set the stage for an example of how this can be accomplished. Compression packing is still widely used to seal rotating equipment such as pumps.
All three API Plan 53 versions are intended to isolate the pumped product from the atmosphere and create a favorable artificial environment for the mechanical seal. Which of the three is optimal will depend on the specifics of the application. The choices of barrier fluid and maintenance capabilities are fundamentally important design considerations. Differences in the three include cooling and pressure capability as well
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In this multi-part series, we will investigate several aspects of centrifugal pump efficiency.
First of Five Parts
Since the original publication of this draft standard in the January 2008 issue of Pumps & Systems, I have received feedback, encouragement, numerous questions and criticism. The draft listed three basic levels of repair.
The McGraw-Hill scientific dictionary [5] states that a volute is "a spiral casing for a centrifugal pump... designed so that speed will be converted to pressure."
