The production of gas appliances is full of unique requirements. Thankfully, there is a unique material perfect for those demands. Liquid Silicone Rubber (LSR) offers physical properties and characteristics that make it ideal for applications involving the control of the flow of gas. The properties and characteristics of LSR, coupled with the precision and output available with the injection molding process to manufacture, are perfectly suited for components used in gas appliances. Thin LSR membranes, valves, seals, and diaphragms can be found throughout gas furnaces, water heaters, washers and dryers, ovens, stoves or grills
Gas appliances are essential parts of many homes and businesses, and ensuring that each component does its job effectively can influence the safety and satisfaction of their users.
WHY LSR IS AN IDEAL MATERIAL FOR COMPONENTS IN GAS PRODUCTS
In gas flow systems, you need components that are compatible with natural gas. LSR is a material with plenty of characteristics that make it excellent for use with gas appliances and components in contact with gas — for instance:
- Inert: Since LSR parts are inert, they are not chemically reactive and won’t degrade or alter their structure in response to natural gas and many other substances. This resilience is important to the function and longevity of the product containing the LSR components.
- Design flexibility: LSR’s physical properties and the precision of injection molding allow for part designs with very thin membranes. Many parts used in gas flow applications are designed with membranes of thicknesses down to 0.12mm to detect the slightest changes in pressure or flow. LSR and LSR two-shot (LSR with thermoplastic) diaphragms, and gaskets with thin part geometries provide the sensitivity needed to detect a change and prompt the response needed repeatedly.
- Low compression set and elongation attributes: The compression set of a material reflects how well it can snap back to its original form after being compressed. LSR withstands compression stress at a very high level and stands up to vibration without losing its strength or shape.
- Thermal properties: LSR is a material that maintains its structure and properties across a wide range of temperatures. It can maintain its flexibility and shape in temperatures as low as -40℃ and as high as 200℃. It won’t elongate at high temperatures, and it won’t become rigid at low ones. Many gas appliances are in locations subjected to a range of temperatures, including outdoor kitchens in the summertime or a water heater in a cold garage or heating up in a poorly-ventilated utility closet. LSR can tolerate changes that come from extreme temperatures.
- Tasteless and odorless: Some gas appliances operate in close proximity to food, so eliminating any factors that could affect taste or smell is beneficial. Other appliances, like dryers, work with clothing and linens, which can easily take on any unpleasant smells released by a product. LSR components in gas appliances do not give off these kinds of odors.
APPLICATIONS FOR LSR COMPONENTS
With such versatile characteristics, it’s no surprise that LSR can be used to create a wide variety of components.
- Flange Seals: Injection molding is used for producing precise liquid silicone rubber gaskets and seals that stand up to harsh environments and can keep unwanted substances out.
- Gas Flow Regulators: The superior design flexibility and sensitivity make LSR diaphragms an excellent option for creating consistent LSR and LSR two-shot diaphragms, and membranes with delicate features sensitive to the slightest changes.
- Pressure Sensors: The material’s flexibility and low compression set makes it an excellent choice for valves that can handle high pressures and revert to their original shape without losing form.
PRODUCTS USING LSR PARTS
Many products make use of LSR parts and components due to their array of useful characteristics. Some appliances that benefit from these parts include:
1. GAS COOKING APPLIANCES
A gas stove top, grill, or oven helps fuel cooking needs for an array of homes and businesses and requires components that stand up to the use of cleaning solutions and other common substances. Since LSR is inert and gas-permeable, any natural gas that moves through the LSR won’t react with it. The precision of liquid injection molding also allows for thin part geometries used in valves that provide sensitive responses to changes in pressure and flow.
Finally, though the components are not typically in direct contact with food items, it helps to minimize the environmental effects they can cause. The parts don’t usually need to be food grade, but the fact that LSR doesn’t give off any taste or odors is a plus.
2. GAS WATER HEATERS
Gas water heaters, also known as geysers, benefit from several characteristics of LSR components, especially their thermal stability and sensitivity.
LSR gaskets, diaphragms and valves are used throughout a water heater. The safety and control valves allow gas to flow to the pilot. Because of the exposure to natural gas, electrical currents, and heat, LSR’s gas permeability, thermal properties and inert behavior make it a good fit and a preferred choice. Additionally, water heaters often end up working in extremely cold or hot temperatures at the peaks of the seasons. LSR components will not suffer under these conditions and can maintain their size and shape.
3. GAS FURNACES AND HEATERS
Gas heaters utilize LSR (1- and 2-shot) diaphragms designed with thin, sensitive membranes, and are present in pressure sensing switches and valves. A low pressure sensing switch used in gas furnaces and heaters are important safety devices used to detect and prevent the heater from running unless the correct venting air pressure is present. Due to the thin, delicate geometry of the LSR diaphragm it is able to sense the accurate pressure level for safe operation.
4. GAS WASHERS AND DRYERS
Gas washers and dryers make use of LSR parts in several ways. They require components that are thermally stable and inert, as well as ones that offer sealing properties.
Gas washers and dryers are typically placed on a wall directly opposite the outdoors, so they must vent to the outside. With this proximity to varying temperatures, the summer and winter climates can necessitate parts that stand up to excessive heat or cold. The exceptional sealing properties of LSR can also help it keep liquids out of the inner workings of the machine.
5. GAS GRILLS
LSR components are perfect for gas grills. They offer thermal stability, inertness, and an effective seal.
Gas grills are unique in that they are often completely outdoors. Extreme temperatures in the summer and winter won’t cause stress to an LSR part, which won’t degrade or lose its shape or rigidity. LSR can withstand the temperatures and help keep the grill functioning as expected. Grills also benefit from the inert characteristics of LSR that allow for gas permeability and its sealing aspects to keep liquids out of the more sensitive components.
BENEFITS OF CHOOSING SIMTEC SILICONE PARTS FOR YOUR LSR COMPONENTS
Using LSR components in gas appliances offers many benefits to the product, but choosing the right company to make them is essential. Working with SIMTEC provides you with an expert hand every step of the way. From material selection and design advice at the start to customized quality assurance systems before the job is done, we work to meet the unique needs of our partners.
We offer several options for the injection molding process, including LSR single-shot, 2-shot, and multi-shot systems. To discuss LSR seals, membranes, diaphragms, and valve component requirements for your gas-permeable applications, contact a SIMTEC representative today.