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Pressure-based adhesive repair for corrosion and leakage in wet gas cabinets – Song Xueqiu (Wuxi Coking Co., Ltd., Wuxi 214026). Our company has a 50,000 m3 wet gas cabinet that has been in use since 1985. During the inspection in October 2005, it was found that there were more than 10 areas of corrosion-induced perforations and cracks at the welds where the top plate of the gas tank met its diagonal side plates. Gas was leaking severely from these defective areas, posing a serious safety hazard. Since there was pressure inside the tank, it was not possible to repair those areas by welding steel plates in place; therefore, it was decided to use a pressure-resistant sealing method to repair the gas tank and extend its service life. 1. Adhesive repair materials: (1) Leak-sealing rods, also known as quick-set steel, are steel-reinforced repair agents in the form of gray, single-piece adhesive rods. They can be used to fill and repair holes, cracks, pores, and broken areas in metal containers and pipes made of steel, iron, or aluminum. These rods have strong adhesion; after being mixed, they are inserted into the gaps and holes to be repaired, and they solidify within 3–5 minutes. They can also be used to seal leaks under pressure, even when the pressure is below 0.3 MPa. (2) Epoxy resin 6101. This adhesive has good flow properties and is easy to mix with auxiliary materials for molding processes. It has the lowest shrinkage rate among thermosetting resins; its shrinkage rate is less than 2% after curing. It features strong adhesion, corrosion resistance, and good cavitation resistance, in addition to being cost-effective and easy to use. (3) Glass fiber cloth. This fabric is resistant to corrosion and has a low rate of contraction when exposed to heat or cold; it is used as an auxiliary material for bonding objects with epoxy resin adhesives, and it is inexpensive. 2 Repair steps: (1) Use a spade to remove rust and oil from around the corroded holes and cracks, then polish with metal sandpaper until the natural color of the metal is revealed. Finally, wipe with alcohol to remove any powder. (2) Cut some sealant that is slightly larger than the hole, knead it quickly, insert it into the hole or crack, and press it with your hand for about 5 minutes until it sets. (3) After removing the hand, apply the prepared epoxy resin to the surface of the clay and its surrounding area using a brush; the area covered should be larger than that of the glass fiber cloth. Then apply the glass fiber cloth, and apply more epoxy resin on top of it. A total of three layers of cloth should be used, with another layer of epoxy resin applied on the surface. The leaky areas in the gas holder holes repaired using the above method have shown no gas leakage over the past 3 years, achieving the desired outcome. 3 Precautions (1) During the patching process, pay attention to the wind direction; try to work in the upwind area and wear a safety mask to prevent carbon monoxide poisoning. (2) The proportions of epoxy resin, curing agent ethylenediamine, and thickener dibutyl ester are 20% and 5% respectively.