Precautions for installing expanded polytetrafluoroethylene sealing strips in heat exchangers

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Heat exchanger I, around the tube bundle: 1. Install the strip gaskets following steps A to D listed above. 2. Fixed with backing tape, allowing vertical installation of the gasket. 3. When closing the flanges, ensure that the strip gasket remains in place. II. In the groove: 1. Carry out the preparations according to steps A to C listed below, and begin laying the strip gaskets in the groove. 2. To complete the gasket installation in Step D, first lay the last 30 cm of strip gasket in the groove and mark the position of the starting cut with a ballpoint pen. 3. Perform the final cutting on the plane. 4. Tear off the remaining portion of the backing tape, place the gasket in the groove with the cut edges overlapping, to complete the gasket installation. III. Partition Bar 1. Flange preparation before installation: Thoroughly clean the surface to ensure optimal adhesion. Wipe away all oil stains, graphite, and other residues. 2. Measure and cut the strip gasket to a length slightly exceeding 3 mm, with both ends cut at 90° angles. 3. Paste the partition gasket. 4. Peel off the backing tape and press firmly on the end of the gasket to insert it into the outer gasket. Lay the strip gasket horizontally on the partition bar and press the other end firmly to insert it into the outer gasket. Note: The partitions inside heat exchangers rarely operate under conditions of large pressure differences; therefore, the butt-cutting method for fitting the outer flange gaskets can provide a sufficient and effective seal. No other cutting methods or installation methods involving overlap at the junction of the partition bars and circular gaskets are recommended. A. Preparations before installation a) Open the flange by at least 15 cm ； b) Thoroughly clean the surface to ensure optimal adhesion ； c) Wipe away all oil stains, graphite, and other residues ； B. First cutting a) Loosen the strip gasket by about 0.5 m. Use a cutting method, with a sharp knife, to cut the end of the gasket on a clean and firm surface ； b) The length Ls of the cut should match the dimensions in the table below, and the cut angle α should be less than 15° ； Thickness of strip gasket (mm), Length of cut (Ls) (mm): 315-20, 625-40. Note: The key requirement during the cutting process is to ensure a continuous and smooth surface; steps are strictly prohibited. When using a cutting tool, be sure to wear appropriate protective gloves. C. Adhesive strip gasket: a) Place the cut end of the strip gasket near the designated starting bolt; b) Peel off small pieces of the adhesive tape at a time to prevent dust from sticking to it. Note: The flange surface must not have any anti-adhesive sprays or liquids on it. At lower temperatures, the strip gasket can be slightly heated before installation. D. Complete the installation of the laminated strip gasket: a) Place the strip gasket over the cut, completing the installation with about 14 mm of excess. Prepare for the second and final cuts by identifying and marking the starting point and ending point ； b) Trim the gasket material at an angle so that the maximum height h matches the dimensions given in the table; this maximum height should be about 20% greater than the thickness of the strip. c) Large flanges may require multiple interfaces, which should be located near the bolt holes and as far apart from each other as possible (approximately 180° between two interfaces, and approximately 120° between three interfaces) ； Striped gasket thickness t (mm), cut length Ls (mm), maximum height h (mm): 315–203.5–5.0; 625–406.5–9.0. ► Fle*ngSeal industrial sealing material: Yes, it is a porous expanded strip manufactured using a special process. This material is soft, compressible, and easy to shape; it can form a good seal at the micro-cracks and damaged areas of the sealing interface under low pressure, thereby effectively protecting brittle structural materials and ensuring a secure connection. Good sealing performance can be achieved for non-metallic materials such as glass, ceramics, graphite, and plastics. It can also compensate for errors caused by machining defects, rigid deformation, misalignment during installation, etc., as well as uneven pre-tightening forces; it effectively addresses leakage issues of various gases and liquids under complex conditions. Fle*ngSeal is a 100% pure polytetrafluoroethylene product, possessing material properties such as resistance to high and low temperatures, resistance to acids and alkalis, corrosion resistance, aging resistance, and self-lubrication. The strip form comes with adhesive, making it extremely convenient to install and use; it is an ideal sealing material for industries such as petroleum, chemicals, pharmaceuticals, papermaking, food and beverages, electronics, power generation, metallurgy, and shipbuilding. For the above content, please indicate the source when reproducing or citing it!