company news about Principle of hot melt welding machine

The hot-melt welding machine adopts a plate-drawing structure and uses an electric heating method. The whole machine is in the form of a frame, composed of three plates: an upper template, a lower template, and a hot template, and is equipped with a hot mold and an upper and lower plastic cold mold. The action mode is pneumatic control. Mainly suitable for welding plastic parts such as household appliances, car lights, and automobile melters. The heating power and mold size can be set according to the size of different plastic parts to realize the welding of a variety of plastic workpieces, with simple operation and convenient use.

This equipment adopts a plate-drawing structure, and the heat of the heating plate is transferred to the welding surface of the upper and lower plastic heating parts by the electric heating method. The surface is melted, and then the heating plate is quickly withdrawn, and the upper and lower heating elements are heated and the melting surfaces are fused, solidified, and integrated. The whole machine is in the form of a frame, composed of three plates: an upper template, a lower template, and a hot template, and is equipped with a hot mold and an upper and lower plastic cold mold. The action mode is pneumatic control. Mainly suitable for welding plastic parts such as household appliances, car lights, and automobile melters. The heating power and mold size can be set according to the size of different plastic parts to realize the welding of a variety of plastic workpieces, with simple operation and convenient use.

⑴ Hot melt butt

Hot-melt butt joint is a method in which the ends of polyethylene pipes are heated and melted by a heating plate and then butted and fused together, and then fixed and connected together by cooling. Usually, a hot-melt electric welding machine is used to heat the end pipe, make it melt, fasten it together, maintain a certain pressure, and achieve the purpose of welding after cooling. Polyethylene pipes of all sizes can be connected by hot-melt butt joints. However, capacitor connection is recommended for pipes with a nominal diameter less than 63mm. This method is economical and reliable, and its interface has higher strength than the pipe itself in both tension and pressure.

Ready to work. The butt joint pipe sections should be of the same pipe material, and the same factory supporting materials should be used as far as possible; the butt pipe section outer diameter and wall thickness should be the same; the inner and outer surfaces of the welded pipe and pipe fittings, especially near the ports, should be smooth and flat without abnormal shapes; the size of the pipe Deviations should meet the requirements; the butt pipe section should have good processing and welding performance matching the welding machine; check the matching of the welding system and power supply, clean the heating plate, connect the power supply of each part of the welding machine, and should have grounding protection ; Set the heating plate temperature to the welding temperature according to the welding process parameters given by the welding machine; if it is an automatic welding machine, also set parameters such as heat absorption time and cooling time.

⑵Hot melt socket connection

Hot-melt socket connection In hot-melt socket connection, two pipe end parts to be connected are respectively heated and melted with the two ends of a thicker connecting pipe section. In this way, each joint requires two heat melting processes.

When hot-melt socket connection, the pipe port should be chamfered and the connection surface should be cleaned. Draw markings on the socket end, and use a heating tool to heat the connecting surface of the pipe and pipe fittings at the same time. When DN≥63mm, use mechanical heating tools, otherwise manual heating tools. After heating, immediately withdraw the heating tool, and use a uniform external force to extend the socket into the socket to reach the depth of the standard line, and form a uniform flange at the end of the socket.

⑶The selection and quality control of hot melt connection method

The selection of the hot-melt connection method mainly depends on factors such as the grade and density of the plastic pipe. The connection method of the plastic pipe should also be in accordance with the relevant regulations such as the buried "Technical Regulations for Polyethylene Water Supply Pipe Engineering" (GJJ101-2004). Most polyethylene pipes can be joined together by two hot-melt methods. However, some high-density polyethylene pipes cannot be connected by means of undertaking. When used in buried heat exchangers, polybutene is generally a socket connection. Both connection methods can be used properly to get a firm joint. Proper use of the two connection methods can result in a firm joint, which is stronger than the pipeline itself.

⑷Electrofusion connection process

① Preparation and precautions. The butt joint pipe sections should be made of the same material, and at the same time, the same factory supporting materials should be used as far as possible; the butt pipe section outer diameter and wall thickness should be the same, and the error should be within the allowable range; the inner and outer surfaces of the pipes and fittings to be welded should be smooth and flat without abnormal shapes; Butt joint pipe sections should have good processing and welding performance matching the welding machine. When welding in cold climates and high winds, protective measures should be taken; the surface to be welded must be scraped off and clean before welding; the electrofusion pipe fittings should not be unpacked when not in use, and strictly follow the welding machine manual and the pipe fitting barcode. Time value for welding; during the welding process and after the completion of the cooling phase, do not move the connector or apply any external force.

②The operation points of electrofusion connection. Clean the dirt on the connecting surface of the pipe, mark the insertion depth, and scrape off its skin; fix the pipe on the frame, and put the electrofusion pipe on the pipe; straighten the connecting piece to ensure that it is on the same axis; power on and weld; cool down. When connecting, the selection of voltage and heating time when energized heating should comply with the regulations of the manufacturers of electrofusion connection equipment and pipe fittings. During the cooling of the electrofusion connection, do not move the connection or apply any external force on the connection.