Repair Care International DRY SEAL® Replacement Putty Elastic Glazing Sealant White

Product Information

One solution might be the double mounting of mechanical seals that provide the necessary lubrication, provided they are compatible with the product, which is not always possible. The following points shall be thoroughly analyzed prior to the replacement of Liquid seals with DGS. 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. Dry seals offer an alternative for dusty or extremely viscous applications that guarantees complete sealing, minimum maintenance, protection of the other system components such as the wear of the shaft and less energy consumption due to motor friction. Large numbers of dry gas seal assemblies have problems because of an issue with an O-ring or a V-ring. There are many sealing elements (O-rings, V-rings, U-rings, etc.) in a seal assembly, which can cause seal operational problems. If an O-ring or a V-ring allows gas to bypass, the gas stream would pass up the primary vent. In many cases, the deterioration of a ring or a sealing element may explain the rise in the primary vent flow, which could be confused with seal face deterioration.

Any traces of DRY SEAL on glass can be easily removed after a few hours or preferably the next day.This makes Dry Seals a far superior option to using a wet seals solution. A wet seal solution to filling joints is enormously damaging to our environment as the amount of waste material generated worldwide is only adding to the severe global epidemic our planet earth is already facing due to the amount of plastic waste mankind is already generating. Figure 2. An example of a 3D model of a modern dry gas seal. The dry gas seal details are shown in this 3D model. Figure 1 shows an example of a modern centrifugal compressor. The dry gas seals are shown at both ends of the rotor. The seals are located between the process section and the bearing. 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.

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. If painting DRY SEAL do so within a month of application. If painting at a later date, lightly sand to create a key

Buy from the UK biggest’s merchant centres

A minimum shaft speed is required for the operation of dry gas seals. This speed is known as the lift-off speed. Care should be taken for variable-speed turbocompressor operation (particularly steam turbine- and gas turbine-driven compressors) to ensure the operation is always above the specified minimum speed for the dry gas seals. Steam turbine- and gas turbine-driven compressors usually require cool-down operation at low speed after a shutdown and this low speed rotation should be performed with respect to the specified minimum speed for the dry gas seals. Historically, many dry gas seals have been damaged in low-speed operations. Through all this, many dry gas seal designs were identified as unsuited for the applications in which they were installed—including the use of improper materials of selection that resulted in seal failures, incorrectly installed seals that limited seal life and poor dry-gas-seal panel designs that caused unnecessary compressor shutdowns. In many instances, when designing dry gas seal panels, little consideration has been given to piping configurations, auxiliary systems and utility costs even though all these affect the reliability of dry gas seals. The seal gas filter system: Standard filters are typically small in capacity and large in the mesh size. For dry gas seals, filters should be 2-5 times larger (in terms of capacity), and 3-4 times smaller in mesh size than typical standard models. As noted earlier, it is not uncommon for dry gas seal systems to employ filtration of 1 micron or less. Full cure up to two weeks depending on climactic conditions. Tools and equipment must be clean and dry prior to use but can be kept wrapped in plastic during short breaks in use.

The first dry gas seal for a compressor was patented by Kaydon Ring & Seal in 1951 when it was known as Koppers Corporation. Field applications of dry gas seal designs were completed in 1952. The original patent was for Kaydon's "Tapered Ramp" lift geometry, a constant diameter / variable depth dynamic lift design. From that first dry gas seal ever manufactured for a centrifugal compressor in 1951, Kaydon Ring & Seal has been instrumental in developing the dry gas seal into one of the most reliable and maintenance free sealing solution available today. To prevent a dangerous condition, process gas cannot leak into the bearing cavity, which could cause an explosion or expose operators or the environment to hazardous or toxic gas. To eliminate this danger, a separation seal (Figure 2) is used on the atmospheric side of the dry gas seal. Since a number of separation seals are available, selecting the correct seal for the application is important.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. Sometimes the differential pressure is higher than normally designed differential pressure, thus indicating a higher flowrate than designed; as noted it could result in inefficient performance or a malfunction. Often the differential pressure is lower than the designed value, which could be as a result of wear in the inner labyrinth seal.

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. Seal gas booster: A commonly reported root-cause for seal failures has been low pressure of seal gas at startup, which resulted in dirty gas moving to the dry gas seal from the compressor casing. It is recommended to install seal gas boosters to ensure supply of seal gas during standstill and transient conditions, if a reliable source of seal gas with suitable conditions is not available for these transient times (particularly the startup). Figure 1. An example of a modern centrifugal compressor. The dry gas seals are shown at the both ends of the rotor. The separation seal is installed between the compressor bearing and the secondary dry gas seal. The separation gas system function (the barrier seal system function) prevents lubrication oil from entering the dry gas seal. The nitrogen flow into the separation seal should be properly monitored. In many machines, the nitrogen supply system (such as control valves, control setting, etc.) does not receive proper attention, which could eventually result in seal problems and even seal failures. A low flow of nitrogen through the separation seal may allow the bearing lubrication oil to migrate into the seal chamber, causing seal face failure. A low flow of nitrogen is sometimes the product of an inaccurate setting of control valves on the nitrogen seal supply line. Dry gas seal root cause analysisDouble opposed seal - Used when the processed gas is abrasive (like hydrogen) and lower pressure designs. This effect should not be confused with the "beading" effect often associated with water repellents. Dependent on the substrate, type and degree of soiling, we recommend the use of one of our Masonry Fungicide Productsor Green Gone Path & Patio Cleaner. When cleaning, make sure that the masonry is damaged as little as possible.