JWT Rubber & Plastic Co.,Ltd

Passive radiators are not super advanced alien technology; in fact they are very simple. A passive radiator performs the same duties that a "bass-reflex" port tube/hole does, but a passive radiator has many advantages over ported designs. The physical positioning of a passive radiator is not as crucial as that of a tuned port hole. This fact is important as it means there is less risk of error during the engineering process. As stated above, passive radiators also enable the use of smaller enclosures. This is because in order for a port tube to provide the same air mass as the speaker cone, the port tube may be physically large, which would require a larger speaker cabinet. (Remember, the port tube must be inside the cabinet.) Speaker boxes featuring passive radiators are much easier to adjust/tune than ported cabinets. Tuning a bass reflex port tube is a very complicated process which involves much mathematics to achieve. Tuning a passive radiator is very simple b...

Passive radiators allow woofers to produce deep tones that otherwise may not have been possible. Depending on the tuning when incorporated, a passive radiator will start to move as the drive woofer begins to produce lower frequencies. By engaging at this point, the passive radiator absorbs energy from the drive woofer thus reducing the drive woofer's motion (we call this dampening). Since the drive woofer is now moving less, there is less risk of damage occurring due to over excursion (speaker moves so far it breaks). There are two main advantages here: 1.   The motion of the drive woofer is dampened thus flattening the frequency response; this makes for smooth sound reproduction. 2.   Passive radiator systems can have the same sonic output as larger speaker cabinets, but in a much smaller size*. In a nutshell, when a passive radiator is tuned properly it can greatly enhance the sonic capabilities of a speaker in regards to low frequency production. ...

How Passive Radiators Work A passive radiator speaker is a simple device that increases the low frequency response (Bass) of a speaker system*. When used properly, a passive radiator can give a speaker system the comparable performance characteristics of a much larger system; that's the point, in a nutshell. A lot of air needs to be moved in order to produce audible bass frequencies. Traditionally, when it comes to bass production, a larger woofer meant louder, clearer bass. Passive radiator technology has broken this tradition. What is a Passive Radiator? A passive radiator looks like a normal driver (speaker) from the front, but on the backside, it appears to have had all of its "guts" removed. See the picture on the right. A passive radiator is a speaker without the magnet, and electronic structure attached to it; it is just the cone, suspension, and frame. Really though, a normal speaker can be used as a passive radiator, the "guts" would just be ...

Natural rubber , also called  India rubber  or  caoutchouc , as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds, plus water. Malaysia and Indonesia are two of the leading rubber producers. Forms of polyisoprene that are used as natural rubbers are classified as elast omers. Currently, rubber is harvested mainly in the form of the latex from the rubber tree or others. The latex is a sticky, milky colloid drawn off by making incisions in the bark and collecting the fluid in vessels in a process called "tapping". The latex then is refined into rubber ready for commercial processing. In major areas, latex is allowed to coagulate in the collection cup. The coagulated lumps are collected and processed into dry forms for marketing. Natural rubber is used extensively in many applications and products, either alon...

Let’s be honest, passive radiators add a whole lot more to the cost of a system than a standard port, even though they both work on the same principles. Now, you might hear some say that a passive radiator system acts more like a sealed box, but that is an audio myth.  Passives tune a box the same way a port does . They act as a resonance system coupled to the air spring inside the box and resonate based on their tuning. For both passives and ports, the box volume plays a role in that tuning and output. For passives, the weight added to the passive helps tune it to its final level, whereas a port is tuned using the surface area of the opening and length. Given that both play the same role in speaker design, you might ask why anyone would choose the much more expensive passive radiator over a cheap piece of plastic tubing of which most ports are made. There are a few things you need to consider when designing a ported system. First, you want to make sure the vent air velocity...

Nitrile rubber , also known as  NBR ,  Buna-N , and  acrylonitrile butadiene rubber , is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. Trade names include  Perbunan ,  Nipol ,  Krynac  and  Europrene . Nitrile butadiene rubber  ( NBR ) is a family of unsaturated copolymers of 2-propenenitrile and various butadiene monomers (1,2-butadiene and 1,3-butadiene). Although its physical and chemical properties vary depending on the polymer’s composition of nitrile, this form of synthetic rubber is unusual in being generally resistant to oil, fuel, and other chemicals (the more nitrile within the polymer, the higher the resistance to oils but the lower the flexibility of the material). It is used in the automotive and aeronautical industry to make fuel and oil handling hoses, seals, grommets, and self-sealing fuel tanks, since ordinary rubbers cannot be used. It is used in the nu...

Plastic recycling  is the process of recovering scrap or waste plastic and reprocessing the material into useful products. Since the vast majority of plastic is non-biodegradable, recycling is a part of global efforts to reduce plastic in the waste stream, especially the approximately 8 million tons of waste plastic that enters the Earth's ocean every year. Compared with lucrative recycling of metal, and similar to the low value of glass, plastic polymers recycling is often more challenging because of low density and low value. There are also numerous technical hurdles to overcome when recycling plastic. When different types of plastics are melted together, they tend to phase-separate, like oil and water, and set in these layers. The phase boundaries cause structural weakness in the resulting material, meaning that polymer blends are useful in only limited applications. The two most widely manufactured plastics, pol...

Posted by Sally Yu  on June 26th, 2018 What are elastomers?  The term derives from “elastic”-one of the fundamental properties of rubber.   The words “rubber” and “elastomer” are used interchangeably to refer to polymers with viscoelasticity-commonly referred to as “elasticity.”  The inherent properties of elastomers include flexibility, high elongation and a combination of resilience and damping (damping is a property of rubber that causes it to convert mechanical energy to heat when subjected to deflection).  This unique set of properties makes elastomers an ideal material for gaskets, seals, isolators, and the like. Over the years, elastomer production has migrated from natural rubber yielded from tree latex to highly engineered rubber compounding variations.   In creating these variations, specific properties are attained with the help of additives such as fillers or plasticizers or by varying content ratios within the copolymer structure....

Normally, the rubber include the EPDM, NBR, FKM, Viton and so on. Silicone Rubber is a man-made elastomer made up primarily from silicone, hydrogen, carbon and oxygen with catalysts that cure it into a rubber with heat. There are many formulations used, and Silicone Rubber is able to support many different additives that means it can be used in a very wide range of applications. Some of the main advantages of Silicone Rubber are its inherent wide temperature ranges, typically -60°C to + 200°C , excellent weather(long rainy season), UV and Ozone resistance, excellent elongation and shape memory characteristics, natural resistance to moisture and biological growth, natural self extinguishing properties, and its ability to be produced in a huge range of colours and hardness’s. Applications where Silicone Rubber’s properties make it a key material choice include medical and life science, any extreme (high or low) temperature environment, flame retardant and low smoke emissi...