Why Choose Custom Rubber Molding?
Custom rubber molding is the ability to create a design and
have it manufactured on the spot by a rubber molding manufacturer. Customized
designs are better for certain companies that require unique designs for their
needs and new products. There are many other ways to create custom products,
but not all methods are best for all uses.
Rubber molding is beneficial because it offers a variety of
services to the user. For injection molding, the costs of custom rubber molding
is lower than some other forms of rubber manufacturing. In large volume runs,
injection rubber molding is the ideal choice.
When using custom rubber molding, the run time of the process
is reduced. This will save both time and money for large volume rubber runs.
Machines using the latest molding technology have a variety of automation
capabilities that reduces the cost of custom molding even lower. Using a
material like liquid silicone rubber creates precision, tight tolerance parts.
It is possible to create products with a variety of finishes and textures when
using rubber molding.
Some of the industries that can benefit from custom molding
Medical: Custom devices, blood analysis machines, surgical
Electronics: Electrical connector inserts, EMI shielding,
high performance seals and gaskets.
Aerospace: Cable boots, vibration isolators, power supply
Industrial: oil and gas components, fluid pumps, customized
buttons and vibration absorbers.
There is no end to the types of products you can manufacture
for an affordable price using the techniques of custom molded rubber
Rubber molding is the process by which raw rubber is melted and formed in a mold. It is the method of choice in the creation of many different kinds of complex rubber products. For example, rubber seals and rubber diaphragms, which prevent seepage of liquids or gasses, must be precisely designed in order to fit the equipment in which they are installed. The same is true for rubber grommets and rubber washers, both of which must be precisely designed, because they are used to protect equipment. Extrusion can produce seals, diaphragms, grommets and washers, but an extruded seal or grommet's construction is limited to detail in two axes. This means that an extruder can produce three-dimensional shapes, but it only has design control over the X and Y axes (the rubber product grows in the Z axis as rubber passes through the extrusion die). For this reason, extrusion is more appropriate for the production of simple rubber sheets, rubber baseboards and other long or thin rubber products. Because rubber molding processes use enclosed molding cavities instead of open dies, molding allows for design control over all three axes. Natural rubber as well as synthetic rubbers like neoprene, silicone rubber, liquid silicone rubber, EPDM and foam rubber can all be molded.
Every industry makes use of some variety of molded rubber products to some extent. Manufacturing operations that involve machinery often must contend with issues of vibration caused by moving parts. In order to protect workers, other machinery and the vibrating equipment itself, machinery that creates vibration is often secured using rubber washers or bushings that absorb vibration and prevent excessive movement. Rubber sheets are also used to absorb vibration; large, thick sheets are often placed beneath machinery that creates vibration. This also can reduce noise, which improves working conditions. Rubber grommets are used in industrial, commercial and consumer contexts. A rubber grommet is a rubber shape that fits around a hole in a surface; the grommet can protect wires or other hardware that passes through the hole, or grommets can protect the holes from becoming torn or otherwise damaged. Wire entry ports in electrical paneling are often fitted with grommets to prevent wires from becoming damaged or disconnected. Simple rubber grommets can also be used in office desks, which are often drilled with holes to allow for the passage of wires from computers and other office hardware to electrical outlets.
For every given molded rubber product application, a host of raw rubber materials are available. Natural rubber, which may be the best known rubber variety, has been in use on an industrial scale since the 19th century (rubber's first suspected uses are prehistoric, and the earliest known use of primitive rubber was by the Mayans around 1600 B.C.E.). Fueled by conflict and scarcity during the first half of the 20th century, synthetic rubber development flourished and gradually began to replace natural rubber development; natural rubber now accounts for less than half of all the rubber materials produced worldwide. Neoprene was the first synthetic rubber produced on an industrial scale, and it and other materials like it feature all of the desirable qualities of natural rubber, but few of its undesirable qualities. Synthetic rubber like EPDM, silicone and neoprene can be engineered to varying levels of resistance to corrosion, chemical inertness, heat resistance, ozone resistance, strength, durability, flexibility, rigidity and many other properties. Industries for which natural rubber products were not practical can now enjoy the benefits of rubber products without enduring the problems they can also cause. Health care facilities, for example, which make extensive use of rubber tubing, must make considerations for patients with latex allergies (natural rubber is derived from rubber latex). Silicone tubing allows for the transmission of intravenous fluids without causing allergic reactions.
There are many kinds of rubber molding, the most common of which are injection molding, liquid injection molding, compression molding and transfer molding. Each method is similar, though of the four injection molding is the most widely employed method of rubber molding. The injection molding process begins with a collection of raw rubber stock in a hopper suspended above a conveyance channel. When the stock is released, a large, turning screw within the conveyance channel forces the stock toward a mold cavity at the end of the channel. Friction caused by the turning screw heats the rubber to a molten state; by the time it reaches the end of the channel, the rubber is completely molten and ready to be formed. The mold at the end of the channel is a specially-designed opening into which molten rubber is injected. The rubber fills the cavity and forms along its contours. The combination of heat and pressure applied to the plastic ensures that it completely fills the cavity, allowing for uniform, complete distribution of rubber throughout the mold. Once the rubber has taken the shape of the mold, it is allowed to cool and harden. The newly molded rubber product is then ejected from the mold, cleansed of imperfections (like seams) if necessary and prepared for shipment or further processing.
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Rubber Products, Inc.
Rubber Molding Types
- is a less-common process of placing a hollow tube between the two halves of a blow mold. The blow mold then closes, pinching off the bottom half of the tube, and air is injected into the top, forcing the material outwards to the walls of the blow mold.
- is a process that compresses the rubber material in a mold under heat and pressure to achieve the desired shape.
- , or Ethylene-Propylene-Diene Monomer, an elastomer, is a type of synthetic rubber.
- Foam rubber is rubber that was manufactured with the addition of a foaming agent in order to create a flexible, air-filled substance.
involves melting rubber in an injection unit and then injecting it into the mold where it stays until after cooling when the finished product is ready.
- Liquid silicone rubber is the liquid form of a synthetic, two-component, elastomeric polymer that is made from silicone elastomers.
- is formed through pressing melted rubber into dies.
- Natural rubber is an elastic hydrocarbon polymer that was originally developed from a milky substance, known as latex, which can be found in the sap of some plants.
- Neoprene is a brand name for a type of synthetic rubber that is also known as polychloroprene.
- Rubber baseboard is a molded rubber product used to cover the joint that is formed when a wall meets the floor.
- Rubber diaphragms are flexible seals that are resistant to a variety of media at different pressures.
- are rubber rings inserted into a hole in sheet metal to protect cords or electrical wires from the abrasion.
- are used to prevent leakage at joints.
- Rubber sheets are flat pieces of rubber used for a variety of purposes.
- refers to long, hollow cylinders used to transport liquids and gases.
- Rubber washers are primarily used to support the weight of a threaded fastener, but also are also used in taps or valves to control the flow of liquids or gases.
- Silicone rubber is a synthetic, two-component, elastomeric polymer that is made from silicone elastomers that can be cured at room temperature into a solid elastomer for use in molding; however, it is usually molded from a liquid form.
involves building a "piston and cylinder"-like device in the mold and squirting the rubber into it through small holes. The mold is then closed and under hydraulic pressure the rubber or plastic is forced through a small hole into the cavity where it cures.
Rubber Molding Terms
- A rubber compound's
capability to withstand mechanically caused deterioration.
- A test made to replicate in a short period
of time the breakdown resulting from normal working conditions.
- A substance that increases the speed of vulcanization
when used in small quantities in conjunction with vulcanizing agents.
- A compound used to increase the effectiveness of an
accelerator, small amounts at a time.
- Tendency of rubber to cling or bond to any surface it
- The continuance of vulcanization, even after the energy
source has been taken away.
- Depressions and marks on the surface of rubber, caused
by air trapped during the molding process.
- Uses steam under pressure to vulcanize rubber products.
- A defect in the molding process, where the rubber near
the parting line sinks below the surface and the parting line ends up
ragged and torn.
- The result of a mixing operation.
- Rubber compound that fills a mold.
- A discoloration of rubber, caused by a liquid or solid
migrating towards the surface.
- The necessary force to start the sliding between
a rubber seal and its mating surface.
- The development of a powdery residue on a rubber surface
as a result of surface breakdown.
- Small cracks on the surface of rubber, usually from
- The permanent deformation of rubber after removing
- Rubber that is able to conduct electricity.
- A chemical bond between polymer chains.
- The date of completion of the molding process for a
- Any of a variety of processes for waste edge removal
from molded rubber parts.
- The application of force used to evenly disperse various
compounds through rubber.
- An instrument that measures the hardness of rubber.
- Applying powder to rubber to prevent adhesion to something
- A seal necessary for the prevention of leaks beyond
parts that are in relative motion.
- A characteristic of rubber, describing its tendency
to return to its initial shape after warping.
- Extension of rubber when exposed to stress.
- A machine that forces rubber through a hole that shapes
it into the finished product.
- The wearing out of elastomers after repeated
- The flexing capability of a material with no
permanent deformation or breakage.
- Capability of uncured rubber to move in the mold and runner
system in the molding procedure.
- Rubber processed on a rubber mill
that has a much greater viscosity than liquid silicone rubber.
- The process of mechanical energy changing to heat
in rubber under strain.
- A material that rubber is chemically or physically bonded
to during the molding process.
- Slow recovery rate of rubber after stress.
- The softening of raw rubber by mechanical and atmospheric
- A chemical compound that is able to endure polymerization.
- A defect that occurs when the rubber does not completely
fill out the mold.
- A line on the surface of rubber resulting from where
the two halves of the mold met.
- A material that is used to quicken the softening of
rubber compounds under heat or mechanical action.
- An insoluble compound that gives rubber its color.
- The degree to which rubber will retain deformation.
- Chemical reaction in which one or more simple
materials are transformed into complex materials that have different
properties from the originals.
- A substance that is added to rubber to increase
its resistance to the harms of the vulcanization process.
- The result when rubber vulcanizes too quickly.
- Extra material that leaks from the mold as it closes.
- The term for the uniting of two parts of vulcanized rubber
to make a whole.
- A thermo-setting
reaction that involves the use of pressure and heat, and results in highly
increased elasticity and
strength of materials like rubber.