[{"content":" As thermally operated pressure relief components, fusible plugs are used across many industries due to their simple construction and reliable operation. Some examples are listed below: Compressed Gas Cylinders / Air Bottles # The picture above shows a multi function valve with fusible plug installed for Chlorine cylinder. Typical gas cylinders that require fusible plug protection include:\nChlorine Acetylene Oxygen CNG (compressed natural gas) LPG (liquefied petroleum gas) We have fusible plugs available for high-pressure gas cylinder. Please consult us for details.\nA/C Condenser, Receiver-Drier # When the condenser of refrigeration unit experiences bad cooling or overload, the temperature of refrigerant in the condenser or receiver-drier may rise to dangerous levels. To prevent compressor damage caused by overheating of the refrigerant, fusible plugs are required. This application is common in air conditioning systems, heat pumps, automotive A/C, and truck container refrigeration. When the pressure of the refrigerant reaches about 3 MPa, the temperature will rise to the melting point of the fusible alloy. The refrigerant will be released from the central hole of the fusible plug, thereby protecting other components in the system from damage due to overheat and over-pressure.\nFluid Coupling # A fluid (hydraulic) coupling protects motors and machinery from excessive torque. Heat generated by the hydraulic coupling depends on the transmitted torque. In the case of prolonged overload, the temperature can exceed the limits that can be tolerated by the oil, the seals and the bearings.\nTo prevent this, fusible plugs must be installed. Many national regulations require that all operation-ready couplings be equipped with at least one fusible plug. There are normally 2 to 3 plugs installed on each coupling.\nFusible Loop Systems # Fusible loop system is used for fire / heat detection in oil and gas plant. Compared with flame or smoke detectors, heat detector is slow in detecting fire because it only activates once a fire has produced sufficient heat of which heat detector could respond. However, they can serve as a useful backup or an alternative.\nA Fusible Loop System consists of the following: fusible plug, tubing network, fusible loop charge panel. When a fire occurs and the ambient temperature rises by about 30°C above normal, the fusible plug (71°C or 100°C) will melt. The air in the loop relieves and subsequently the pressure inside the tubing reduces. This pressure drop is detected by a pressure transmitter in the control panel, which then signals the control room. The system can subsequently activate alarms, trigger an ESD, or open a deluge valve.\nFor rapid response, the orifice diameter of the fusible plug should match the tubing diameter (about 8 mm). Our 1/2″NPT fusible plugs meet this requirement perfectly.\nSteam Boilers # Fusible plugs are installed in steam boilers to warn of low water levels or overpressure. A fusible plug is threaded into a hole in the crown sheet of each combustion chamber, usually from the fireside. When the water level drops to the level of the crown sheet, the plug becomes exposed to heat and the fusible alloy melts, leaving a hole through which steam will blow into the combustion chamber and furnace, giving warning to the fireman.\nDue to the difference in local regulations, fusible plugs for steam boilers may look very different in different countries. As long as customers can provide the required specifications — including dimensions, temperature ratings, and/or pressure ratings — we can manufacture according to their requirements.\nHeat Melt Plugs for Blowers # Sinomas heat melt plugs are used to protect blowers from overheating. They activate thermally when the blower’s discharge temperature exceeds its safe limit. Our plugs are totally customizable regarding the temperature of activation, plug materials, thread type and size etc. The advantages are:\nUnique thread pattern and left-hand thread prevent overriding with conventional pipe plugs. No expulsion of melt metal when activated Audible alert when activated Typical activation temperature: 390°F / 199°C Upon request we can supply replacements compatible with existing market models, for example Tuthill 92278 BLOWERS- SHUR-MELT PLUG, T5CDL Series blower heat plugs, etc.\nAircraft Tire Wheels # To prevent explosions caused by excessive brake heat, all aircraft tires are equipped with both fusible plugs and pressure relief valves for double security. For example, on Boeing 757 the fusible plug melts at around 200°C and the pressure relief valve will release the pressure at 375-450 psig. This means that even if the wheel temperature exceeds 200°C, the fusible plug will melt before pressure reaches a dangerous level.\n","externalUrl":null,"permalink":"/applications/","section":"Fusible Plug Expert","summary":"","title":"Applications","type":"page"},{"content":"","externalUrl":null,"permalink":"/authors/","section":"Authors","summary":"","title":"Authors","type":"authors"},{"content":"","externalUrl":null,"permalink":"/categories/","section":"Categories","summary":"","title":"Categories","type":"categories"},{"content":"Sino Material technologies Limited\nAddress: C201, Building 3, 500 Jianyun Road, Shanghai 201318, China\nWeb: https://www.sinomas.com/\nEmail: inquiry@sinomas.com\nTel: +86 21 58095179\nFlex Heat GmbH\nAddress: Kantstraße 38, 40667 Meerbusch, Germany\nEmail: inquiry@sinomas.com\nTel: +49 152 0393 0593\n","externalUrl":null,"permalink":"/contact/","section":"Fusible Plug Expert","summary":"","title":"Contact","type":"page"},{"content":" Custom fusible plugs for pressure vessels, fire protections, heat pumps, etc. — shipped worldwide.\nWe produce eutectic fusible alloys in house. Compared to other suppliers who source fusible alloys from outside, we know how and we know why. This is very important for safety critical components.\nWhat is Fusible Plug? # Fusible plug, occasionally also called fuse plug, solder plug, is thermally operated non-reclosing pressure relief device that functions by yielding or melting of the fusible alloy1 sintered in plug body.\nFusible plugs only respond to over-temperature2. Compared to other type of safety devices, their structures are simpler and require no maintenance. Meanwhile they are very reliable if you buy from quality manufacturers like us.\nBrowse NPT Series Our Advantages # SINOMAS has been in this market for 25+ years. We treat quality above anything else. This is not only what we say, but also what we do, in many aspects that you might not be aware of. We have the test facilities in house, ensuring that every product we deliver is fully qualified.\nAll fusible plugs can be custom designed based on your requirements. It can be either product development for new project, or replacement of existing fusible plugs of other brand3.\nPlug Material Options # Fusible plug body can be made with the following materials:\nBrass, optionally with Tin or Nickel plating Stainless steel, corrosion resistant and high mechanical strength Bronze, mainly used for steam boilers Aluminum, for light weight demanding applications, for example aircraft wheel tires. Due to the good machinability, brass is ideal for small batch (typically fewer than a few hundred pieces) custom orders. However brass fusible plugs can’t withstand high process pressure. Be sure to check with us before ordering.\nThread Type # Different thread types are popular in different countries and industrial segments. We are a global supplier and are familiar with the major thread specifications in the world: Metric, NPT, BSPP (G), BSPT (R), UNC, etc.\nRequest a Quote Fusible alloys are low melting alloys (≤ 229°C) that are mainly comprised of Bismuth, Tin, Indium and Lead. The formulae are different for different temperature ratings. RoHS compliant fusible plugs are available upon request.\u0026#160;\u0026#x21a9;\u0026#xfe0e;\nAvailable temperature ratings can be found in site page NPT Series.\u0026#160;\u0026#x21a9;\u0026#xfe0e;\nWe are not a retailer. MOQ applies to all orders if not in stock.\u0026#160;\u0026#x21a9;\u0026#xfe0e;\n","externalUrl":null,"permalink":"/","section":"Fusible Plug Expert","summary":"","title":"Fusible Plug Expert","type":"page"},{"content":" We are able to produce any fusible plugs according to customer specifications including thread type and sizes, plug body material, etc. In practice NPT fusible plugs of the following sizes and yield temperatures are considered to be standard models due to their popularity in application. These plug bodies, both brass and stainless steel, are often in stock, resulting in shorter delivery times.\nStandard Model List # °F °C 1/8″NPT 1/4″NPT 3/8″NPT 1/4″NPT 1/4″NPT 3/8″NPT 1/2″NPT Brass Brass Brass Brass SS SS SS 136 58 AQS18-58 AQS14-58 AQS38-58 AQS12-58 AQS14-58SS AQS38-58SS AQS12-58SS 160 71 AQS18-71 AQS14-71 AQS38-71 AQS12-71 AQS14-71SS AQS38-71SS AQS12-71SS 165 74 AQS18-74 AQS14-74 AQS38-74 AQS12-74 AQS14-74SS AQS38-74SS AQS12-74SS 180 82 AQS18-82 AQS14-82 AQS38-82 AQS12-82 AQS14-82SS AQS38-82SS AQS12-82SS 195 90 AQS18-90 AQS14-90 AQS38-90 AQS12-90 AQS14-90SS AQS38-90SS AQS12-90SS 212 100 AQS18-100 AQS14-100 AQS38-100 AQS12-100 AQS14-100SS AQS38-100SS AQS12-100SS 230 110 AQS18-110 AQS14-110 AQS38-110 AQS12-110 AQS14-110SS AQS38-110SS AQS12-110SS 255 124 AQS18-124 AQS14-124 AQS38-124 AQS12-124 AQS14-124SS AQS38-124SS AQS12-124SS 281 138 AQS18-138 AQS14-138 AQS38-138 AQS12-138 AQS14-138SS AQS38-138SS AQS12-138SS 361 183 AQS18-183 AQS14-183 AQS38-183 AQS12-183 AQS14-183SS AQS38-183SS AQS12-183SS 390 199 AQS18-199 AQS14-199 AQS38-199 AQS12-199 AQS14-199SS AQS38-199SS AQS12-199SS 445 229 AQS18-229 AQS14-229 AQS38-229 AQS12-229 AQS14-229SS AQS38-229SS AQS12-229SS Dimensions # Thread Size H(mm) T(mm) S(mm) Orifice(mm) 1/8\u0026quot;NPT 16 5 12 5 1/4\u0026quot;NPT 21 6.5 14 5 3/8\u0026quot;NPT 20 6 17 6 1/2\u0026quot;NPT 29 8 22 8 Product Specifications # Tolerance of yield temperature: ±3°C Plug body material: brass / stainless steel Eutectic alloy consisting of multiple components Test pressure: 3.0 MPa (higher pressure upon request) Max service pressure: 5 MPa for brass, 15 MPa for stainless steel HS code: 8481809000 ","externalUrl":null,"permalink":"/standard-models/","section":"Fusible Plug Expert","summary":"","title":"NPT Series","type":"page"},{"content":"Fusible plugs are very niche products with very segmented applications. There is no universally recognized international standard dedicated exclusively to fusible plugs. We can only find a few discrete sentences from some industrial standards where fusible plugs are included, e.g. refrigeration (UL207-2004), compressed air cylinder (ISO3807-2), steam boilers and compressed air applications (BS 1123:2006).\nThese standards specify two common types of tests in common regarding fusible plugs: the yield temperature test and the hydrostatic test. Yield temperature test is to verify that the fusible plugs operate at their designated temperature. Hydrostatic test tells whether the fusible plugs can continuously withstand normal operating pressure without leakage.\nWe have necessary test devices in house to check every aspect of the performance of our fusible plug. Our test results are often more reliable than third-party certificates. You can rest assured with the quality of every single product we deliver. Other types of test (including RoHS) certificates can be arranged upon agreement.\nApplication Note # We make sure that all our products function as they are designed to be. However it is the customer’s responsibility to choose fusible plugs with the right temperature rating for their application. Apply anaerobic sealing adhesive or thread sealing tape for installation to avoid leakage. Please inform us if the service pressure of your application is higher than 5.0 Mpa. Fusible plug does not protect against over-pressure from improper charging practices. In other words, fusible plugs only respond to over-temperature instead of over-pressure. Please replace the fusible plugs if you know that they have been exposed to over-temperature within 10°C of their nominal yield temperature, even if no leakage is currently observed. ","externalUrl":null,"permalink":"/quality-assurance/","section":"Fusible Plug Expert","summary":"","title":"Quality Control","type":"page"},{"content":"","externalUrl":null,"permalink":"/series/","section":"Series","summary":"","title":"Series","type":"series"},{"content":"","externalUrl":null,"permalink":"/tags/","section":"Tags","summary":"","title":"Tags","type":"tags"}]