Dry Seal Multi-Purpose Glazing Sealant is a durable alternative to linseed oil putty for use on wooden and metal windows for maintenance, renovation and restoration. Adjoining Surfaces: Due to the thixotropic nature of this product, where it is applied by brush or roller, accidental contamination of non-target surfaces can usually be avoided by taking reasonable care. To create the right environment for the seal, contamination must be prevented from entering the seal. From the process side, a process seal is required to prevent process gas from contaminating the dry gas seal environment. On the atmospheric side, where lubrication oil is present, the oil must be stopped from entering the dry gas seal environment. Unscheduled shutdowns caused by loss of control of the seal oil system and/or seal oil pumps/driven failures. In a case study for a turbocompressor, the original seal filter meshing was 4 microns. The upgraded seal filter was a filter system with the 1 micron mesh size and the dimensions 2.5 times larger than the original filter.

Flowmeter on secondary vent: A good recommendation is to consider a flowmeter on the secondary vent. This can give good information regarding the secondary seal health and the overall seal system conditions. Each factor must be analyzed to identify what is required for the application. When selected correctly, they will provide the best dry gas seal system and deliver the highest reliability achievable from dry gas seals. Not only will this provide reliable dry gas seals with a minimum of six years mean time between repairs (MTBR), it will also reduce utility, maintenance and repair costs. The RCA (root-cause analysis) is an important step after a seal failure. After a dry gas seal failure, the seal should be sent to the seal manufacturer’s facility for dismantling and investigation. In case of dirt and contaminations in a seal assembly, all parts and components should carefully be investigated to find a clue about where dirt or contamination comes from. A source of dirt is the seal gas itself, for example, because of insufficient or inefficient seal gas filtration. If the seal gas supply line does not appear dirty, but the seal assembly is dirty, this could indicate that the dirt or contamination entered the seal chamber directly from the compressor casing. The reason could be an insufficient seal gas pressure during transient situations, such as the startup.

Dryseal can easily accommodate most complex roof detailing and can be used on flat and low pitched roofs, on garages, extensions, or to replicate lead sheet on heritage buildings. Remove all failed putty. The substrate must be free of oxidation, dirt, moisture, grease and residual putty, mastic or sealant.

If painting DRY SEAL do so within a month of application. If painting at a later date, lightly sand to create a key Typically, compressors with dry gas seals are used in applications in which they are critical parts of the entire process. A well-designed dry gas seal system will prevent extensive damage to the dry gas seal, compressor and process. Compared to pump operations, dry gas seals and compressors usually operate at higher speeds and pressures. Every component of a dry gas seal must be designed to manage exposure to extreme conditions. The quality of the seal supply gas must also be assessed to ensure that no liquids are formed during changes in gas pressure and temperature. The seal gas will drop in pressure from the supply pressure all the way to the atmospheric side as it leaks through the dry gas seal. Factors that can influence seal gas temperature are process gas temperature or environmental conditions, which can drop the temperature of pipes or the compressor to the point that liquid will form in the seal gas supply. All these conditions must be identified to ensure that no liquids form that will affect the operation of the dry gas seal during dynamic as well as static conditions. A well-known reason for dry gas seal failure (or problem) is dirt (such as dust or contamination) or liquid finding its way to the seal — whether through seal gas or from the inside of the compressor. Dust or contamination inside seal components could potentially cause "hang-up" of the static faces, which might show itself as high seal gas flows at the primary vent.The operation range of seal system instruments: The instrumentation and control systems for sealing systems vary per application. In some of these applications, instruments or valves might be improperly specified. Sometimes the instrument range is not sufficient, and too often seal system flowmeters are not sized properly.

The inner labyrinth seal (or process labyrinth seal) plays an important role in the performance and reliability of a turbocompressor and its dry gas seals. The differential pressure across the inner labyrinth seal should be carefully monitored. This differential pressure needs to be maintained at a relatively constant designed value for uninterrupted and stable flow. A low seal gas flow (to process side) may cause migration of dirty process gas into the seal. A high flow may cause the flow coefficient in the system to exceed the designed value, creating detrimental flow turbulence, as well as inefficient performance. A dry gas seal creates a film of gas (3) between a rotating seat (1) and a stationary face (2). This film of gas (or gap) between the seal faces must be generated and maintained at 150 to 200 micro-inches so the seal faces do not touch and the smallest amount of gas is allowed to leak through the seal.When the rotating seat is turned fast enough to pump gas between the rotating seat and the stationary face Compatible with double-glazed sealed units, all glazing tapes and with laminated, acoustic and safety glass The rotating seat is fixed to the compressor rotor, and the stationary face is connected to the compressor case. The stationary face must adjust axially to maintain the gap as the rotating face/compressor rotor moves and as the compressor case expands and contracts from changes in heat and pressure. To manage axial movement, the stationary face must move freely when required, and as a result, the dynamic secondary sealing design is key to attaining a response to axial changes without resistance or delay. Therefore, a reliable dry gas seal will have a parallel gap of 150 to 200 micro-inches between the rotating seat and the stationary face even when axial movement occurs. The next article, in the March 2012 issue, will focus on selecting the proper seal features—face materials, groove geometries, secondary sealing elements and gasket extrusion/explosive decompression—to provide a reliable dry gas seal system.