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20-432: The park features a 22 Acre lake surrounded by 25 Acres of land. A children's playground is also located in the park which is covered with EPDM , a special rubberised material for comfort and safety. The park also features a 2 km jogging track. This Selangor location article is a stub . You can help Misplaced Pages by expanding it . EPDM rubber EPDM rubber ( ethylene propylene diene monomer rubber )

40-413: A roofing membrane it does not pollute the run-off rainwater (which is of vital importance for rainwater harvesting ). It is used for belts , electrical insulation , vibrators , solar panel heat collectors, and speaker cone surrounds. It is also used as a functional additive to modify and enhance the impact characteristics of thermoset plastics , thermoplastics , and many other materials. EPDM

60-1181: A limit, depending first on the EPDM polymers available, then the processing and curing method(s) employed. EPDMs are available in various molecular weights (indicated in Mooney viscosity ML(1+4) at 125 °C), varying levels of ethylene, third monomer, and oil content. Because of chemical interactions, EPDM degrades when in contact with bituminous material such as EPDM gaskets on asphalt shingles. Relative to rubbers with unsaturated backbones ( natural rubber , SBR , neoprene ), rubbers with saturated polymer backbones, such as EPDM, exhibit superior resistance to heat, light, and ozone exposure. For this reason they are useful in external harsh environments. EPDM in particular exhibits outstanding resistance to heat , ozone , steam , and weather . As such, EPDM can be formulated to be resistant to temperatures as high as 150 °C, and, properly formulated, can be used outdoors for many years or decades without degradation. EPDM has good low-temperature properties, with elastic properties to temperatures as low as −40 °C depending on

80-433: A non-slip, soft, porous safety surface for wet-deck areas such as pool decks. It is used as safety surfacing under playground play equipment (designed to help lessen fall injury). (see Playground surfacing .) Production of synthetic rubber in the 2010s exceeded 10 million tonnes annually and was over 15 million tonnes in each of 2017, 2018, and 2019 and only slightly less in 2020. Cushioning Package cushioning

100-409: Is a type of synthetic rubber that is used in many applications. EPDM is an M-Class rubber under ASTM standard D-1418; the M class comprises elastomers with a saturated polyethylene chain (the M deriving from the more correct term polymethylene). EPDM is made from ethylene , propylene , and a diene comonomer that enables crosslinking via sulfur vulcanization . Typically used dienes in

120-534: Is also used for components that provide elasticity ; for example, it is used for bungee cords , elastic tie-downs, straps, and hangers that attach exhaust systems to the underfloor of vehicles (since a rigid connection would transfer vibration, noise, and heat to the body). It is also used for cushioned edge guards and bumpers on appliances, equipment, and machinery. Colored EPDM granules are mixed with polyurethane binders and troweled or sprayed onto concrete, asphalt, screenings, interlocking brick, wood, etc., to create

140-559: Is always compounded with fillers such as carbon black and calcium carbonate , with plasticisers such as paraffinic oils, and has functional rubbery properties only when crosslinked . Crosslinking mainly occurs via vulcanisation with sulfur but is also accomplished with peroxides (for better heat resistance) or phenolic resins. High-energy radiation, such as from electron beams , is sometimes used to produce foams, wire, and cable. Typical properties of EPDM vulcanizates are given below. EPDM can be compounded to meet specific properties to

160-417: Is critical. Field experience may indicate the types of damage previously experienced. Laboratory analysis can help quantify the fragility of the item, often reported in g's . Engineering judgment can also be an excellent starting point. Sometimes a product can be made more rugged or can be supported to make it less susceptible to breakage. The amount of shock transmitted by a particular cushioning material

180-407: Is dependent on its proper design and use. It is often best to use a trained packaging engineer , reputable vendor, consultant, or independent laboratory. An engineer needs to know the severity of shock (drop height, etc.) to protect against. This can be based on an existing specification , published industry standards and publications, field studies, etc. Knowledge of the product to be packaged

200-445: Is largely dependent on the thickness of the cushion, the drop height, and the load-bearing area of the cushion (static loading). A cushion must deform under shock for it to function. If a product is on a large load-bearing area, the cushion may not deform and will not cushion the shock. If the load-bearing area is too small, the product may “bottom out” during a shock; the shock is not cushioned. Engineers use “cushion curves” to choose

220-422: Is used for door seals, window seals, trunk seals, and sometimes hood seals. Other uses in vehicles include wiper blades, cooling system circuit hoses; water pumps, thermostats, EGR valves, EGR coolers, heaters, oil coolers, radiators, and degas bottles are connected with EPDM hoses. EPDM is also used as charge air tubing on turbocharged engines to connect the cold side of the charge air cooler ( intercooler ) to

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240-410: Is used to create weatherstripping, seals on doors for refrigerators and freezers (where it also acts as an insulator ), face masks for industrial respirators, glass run channels , radiators , garden and appliance hose (where it is used as a hose material as well as for gaskets), tubing , washers , O-rings , electrical insulation , and geomembranes . A common use is in vehicles , where EPDM

260-431: Is used to protect items during shipment . Vibration and impact shock during shipment and loading/unloading are controlled by cushioning to reduce the chance of product damage. Cushioning is usually inside a shipping container such as a corrugated box . It is designed to absorb shock by crushing and deforming, and to dampen vibration, rather than transmitting the shock and vibration to the protected item. Depending on

280-612: The intake manifold . EPDM seals can be a source of squeaking noise due to the movement of the seal against the opposing surface (and its attendant friction). The noise can be alleviated using specialty coatings that are applied at the time of manufacture of the seal. Such coatings can also improve the chemical resistance of EPDM rubber. Some vehicle manufacturers also recommend a light application of silicone dielectric grease to weatherstrip to reduce noise . This synthetic rubber membrane has also been used for pond liners and flat roofs because of its durability and low maintenance costs. As

300-424: The natural frequency of the cushioned item. The process for vibration protection (or isolation) involves similar considerations as that for shock. Cushions can be thought of as performing like springs. Depending on cushion thickness and load-bearing area and on the forcing vibration frequency, the cushion may 1) not have any influence on input vibration, 2) amplify the input vibration at resonance , or 3) isolate

320-425: The best thickness and load-bearing area for a cushioning material. Often two to three inches (50 – 75 mm) of cushioning are needed to protect fragile items. Computer simulations and finite element analysis are also being used. Some correlations to laboratory drop tests have been successful. Cushion design requires care to prevent shock amplification caused by the cushioned shock pulse duration being close to

340-645: The grade and the formulation. EPDM is stable towards fireproof hydraulic fluids , ketones, hot and cold water, and alkalis. As a durable elastomer , EPDM is conformable, impermeable, and a good electrical insulator. Solid EPDM and expanded EPDM foam are often used for sealing and gasketing , as well as membranes and diaphragms . EPDM is often used when a component must prevent fluid flow while remaining flexible. It can also be used to provide cushioning or elasticity . While EPDM has decent tensile strength , its flexibility makes it inappropriate for rigid parts such as gears , shafts , and structural beams. It

360-502: The manufacture of EPDM rubbers are ethylidene norbornene (ENB), dicyclopentadiene (DCPD), and vinyl norbornene (VNB). Varying diene contents are reported in commercial products, which are generally in the range from 2 to 12%. The earlier relative of EPDM is EPR, ethylene propylene rubber (useful for high-voltage electrical cables), which is not derived from any diene precursors and can be crosslinked only using radical methods such as peroxides. As with most rubbers, EPDM as used

380-474: The product from the vibration. Proper design is critical for cushion performance. Verification and validation of prototype designs are required. The design of a package and its cushioning is often an iterative process involving several designs, evaluations, redesigns, etc. Several (ASTM, ISTA, and others) published package testing protocols are available to evaluate the performance of a proposed package. Field performance should be monitored for feedback into

400-417: The specific situation, package cushioning is often between 50 and 75 mm (2 and 3 in) thick. Internal packaging materials are also used for functions other than cushioning, such as to immobilize the products in the box and lock them in place, or to fill a void. When designing packaging the choice of cushioning depends on many factors, including but not limited to: Proper performance of cushioning

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