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Ethylene Acrylate Rubber (AEM, Vamac® )

Ethylene/Acrylic elastomer (AEM, Vamac®)

Ethylene/ acrylic elastomer is a copolymer of ethylene and methyl acrylate plus a small amount of a curesite monomer containing carboxylic acid groups. AEM is a tough, low-compression-set rubber with excellent resistance to high temperatures, hot mineral oil, fluids and weathering. The low temperature flexibility and mechanic properties are better than ACM, but it is not well resistant to low aniline oil (like ASTM No. 3 oil) and polar solvents. AEM is typically chosen for applications requiring improved performance versus Nitrile rubber, Neoprene or reduced cost versus higher-end elastomers such as HNBR, FKM. It also usually is applied in automotive industry.

General Information
ASTM D 1418 Designation: AEM
ISO/DIN 1629 Designation: AEM
ASTM D2000 / SAE J 200 Codes: EE
Standard Color(s): Black
Hardness Range: 40 to 85 Shore A
Relative Cost: Medium- High

Cure system – Amine-Cured

Standard AEM compounds are Amine based vulcanization system.

Characteristics

  • Excellent weather & ozone resistance
  • Very good heat resistance
  • Low compression set
  • Resistant to most oils, greases (even with aggressive additives)
  • Good low temperature properties

Service Temperatures

Standard Low Temperature: -30°C / -22°F
Standard High Temperature: 150°C / 300°F

Applications

Typical applications for AEM are all kind of static seals, hoses, gaskets in contact with oil as it happens in gear boxes, oil pumps, cam covers or others.

Vamac® is a registered trademark of DuPont Performance Polymers.

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Polyurethane

POLYURETHANE (PU)
(Urethane – Polyurethane – Thermoplastic & Thermoset)

Polyurethane is a unique material that offers the elasticity of rubber combined with the toughness and durability of metal. Because urethane is available in a very broad hardness range (eraser-soft to bowling-ball-hard), it allows the engineer to replace rubber, plastic and metal with the ultimate in abrasion resistance and physical cost. Many applications using this ultra-tough material have cut down-time, maintenance time and cost of parts to a fraction of the previous figures. 

Urethanes have better abrasion and tear resistance than rubbers, while offering higher load bearing capacity. Compared to plastics, Urethanes offer superior impact resistance, while offering excellent wear properties and elastic memory.

Urethanes have replaced metals in sleeve bearings, wear plates, sprockets, rollers and various other parts, with benefits such as weight reduction, noise abatement and wear improvements being realized.

Applications:

  • Belts
  • Metal forming pads
  • Wear strips
  • Bumpers
  • Gears
  • Bellows
  • Machinery mounts
  • Cutting Surfaces
  • Sound-dampening pads
  • Chute and hopper liners
  • Prototype machined parts
  • Gaskets
  • Seals
  • Rollers
  • Roller covers
  • Sandblast curtains
  • Diaphragms
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Physical Properties of Rubber – Second Part

Second Part covers Tear Resistance, Ozone Resistance, Low Temperature Resistance.

Tear Resistance

The tearing of rubber is a mechanical rupture process started where forces are concentrated in an area usually caused by a cut, defect or deformation. 

How to Test Tear Resistance

Tear resistance is tested on a tensometer in the same manner as the tensile strength test except the specimen is one of 5 specific shapes: Type A, B, C, T or CP. A graph is produced in the same manner as the stress-strain curve except the Tear Strength graph is force over jaw separation length. Tear strength is calculated by taking the maximum force divided by the median thickness of the specimen (Ts = F/d).
Type A – Crescent shaped specimen with a nick or cut
Type B – Tab End specimen with a nick or cut
Type C – Right Angle specimen with a nick or cut
Type T (Trouser)– Molded block, 150 X 15 X 2mm, with a 40mm cut
Type CP (Constrained path)– Molded specimen 125 X 28.5 X 5.33mm. This is a special molded shape with fabric reinforcement molded in the mid-plane of the sample. The specimen has a narrows groove down the length in the center. 

Ozone Resistance

Ozone (O3), resistance is used to test the relative ability of the rubber compound to resist outdoor weathering or ozone chamber testing. Some applications like door and window trim would be subject to weathering so testing would give an estimation of how the rubber compound will react to weathering. Other sources of ozone exposure include air purifiers and ozone generators used to purify, deodorize, disinfect and kill bacteria in just about everything from air to food. 

How to Test Weathering/Ozone Resistance

ASTM Method D1171 addresses how to test weathering and ozone resistance. In D1171, rectangular cross section samples are wrapped around a wooden mandrel and left in the sun or placed in an ozone chamber. After a period of time either method A or method B is used to grade the samples. In method A no cracking is permitted under 2X magnification and in method B, three samples are checked and graded depending on the severity of cracking and given a quality retention value (expressed as a percentage) derived from Table 1 in ASTM D1171.
 
ASTM Method D1149 is used to test the effects of specific levels of ozone concentration on specimens that are under dynamic or static surface strain conditions. 

Low Temperature Resistance

There are two low temperature tests that are used in testing low temperature properties of elastomers, ASTM D2137, Low Temperature Brittleness, and ASTM D1379, TR-10/TR-70 Temperature Retraction test. Low Temperature Brittleness is the most common low temperature test you will see on a physical properties data sheet. The temperature retraction test is not as common but will give you more accurate continuous operating low temperature results and a better indication of the viscoelastic and crystallization effects at low temperature.

ASTM D2137 – Low Temperature Brittleness 

The Low Temperature Brittleness test is use to determine the lowest temperature at which a rubber specimen will not exhibit fractures or cracks when subject to a specific impact condition. There are two tests methods, A and B. Test Method A is for rubber volcanizates and Test Method B is for rubber coated fabrics. This test is useful for development purposes but may not necessarily indicate the lowest temperature at which the compound will operate. The TR-10/TR-70 Temperature Retraction Test is more effective in determining the lowest temperature at which a compound will continue to operate.

How to Test Low Temperature Brittleness

Specimens are cut from a die and placed into a fixture. The specimens are immersed into a liquid bath at the specified test temperature for a determined length of time. After immersion deliver a single impact to the specimen and note any cracks, fissures or holes visible to the naked eye. Repeat the test at the next highest temperature (usually 10°C increments) until the specimen passes with no cracks, fissures or holes. 

ASTM D1379 – TR-10/TR-70 Temperature Retraction

The TR-10/TR-70 Temperature Retraction test is used to evaluate the crystallization effects and viscoelastic properties of the rubber specimen at low temperature. This test will give you a better indication of compounds lowest temperature at which it will continuously operate. 

How to Test TR-10/TR-70 Temperature Retraction

This test is performed by stretching a die cut specimen in a special fixture to 250% elongation or 50% of the ultimate elongation if 250% can not be obtained. The stretched specimens are immersed in in a liquid at -70°C for 10 minutes freezing the sample to a state of reduced elasticity. Now, after releasing the specimens, slowly raise the temperature of the samples and measure the temperature and length of the specimens at 2 minute intervals. Report the temperature at which the sample retracted 10% (TR10), 30% (TR30), 50% (TR50) and 70% (TR70). 
 
The TR10 value can be used to indicate the low temperature at which it will continuously operate, and it also correlates with the brittle point. The greater the temperature difference between the TR10 and TR70 the greater the tendency of the rubber to crystallize. TR70 also correlates with low-temperature compression set.
 
Understanding the physical properties of rubber will help you determine what properties are important to your application.

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Physical Properties of Rubber – First Part

First part covers Hardness, Ultimate Tensile Strength, Elongation, Tensile Set.

Hardness

Hardness is the measure of how resistant solid material is when a force is applied. There are 3 main type of hardness measurements, scratch, indentation and rebound. We will only be talking about the indentation hardness for elastomers. Indentation hardness is the materials resistance to indentation by an indentor. 
 
Rubber is made in different hardness’ for several reasons. Some sealing surfaces may not be totally smooth. The little voids, pits and scratches allow a pathway for fluid or air to escape through. Softer materials tend to flow better into these voids and imperfections on the sealing surface creating a better seal. On the other hand, harder rubbers will not do this as well but they do resist extrusion cause by high pressures. Also, coefficient of friction is also affected by the hardness of the rubber. Softer rubber has a higher coefficient of friction and harder rubber has a lower coefficient of friction. Coefficient of friction plays a factor when the rubber seal is sealing a part that moves. 

Measuring Hardness

The durometer gauge is used to test the hardness of elastomers. The 3 most common durometer gauges used to measure rubber are Type A, Type M and Type D. Type A is used to test soft rubber materials while Type D is used to test hard rubber and plastic materials. Type M, also for soft materials, was developed to test small specimens, typically O-rings, that do not meet the physical size requirements specified in ASTM D2240. Is is important to know that although each of the hardness scales are graduated from 1-100, these scales are not the same. 90 Shore A is not the same as 90 Shore D or 90 Shore M. A piece of rubber measuring 90 on a Shore A gauge will read around 42-43 on a Shore D gauge. 

Tensile Strength

Ultimate tensile strength, or just tensile strength, is the maximum force a material can withstand without fracturing when stretched. It is the opposite of compressive strength. Have you ever purchased a pair of shoes and they came joined together with a piece of string? Instead of getting a pair of scissors, did you opted to test your physical strength against the tensile strength of the string and try to break it by pulling on it? If the string has a low tensile strength you should be able to pull and break the string easily. You can apply more tensional force than the string can withstand. If it has a high tensile strength it will be much harder to break by pulling. Are you starting to understand what tensile strength is? 
 
Tensile strength is an indication of how strong a compound is. Any time you have an application where you are pulling on the part, tensile strength is important to know. Whether your product is designed to break easily or not at all the tensile strength will let you know how the object will react to the tensional forces. A few rubber products that tensile strength are important would be bungee cords, rubber tie downs, drive belts. Some elastomeric compounds, like Silicone, have a low tensile strength making them unsuitable for a dynamic types of seal because they can fracture easily. 

Measuring Tensile Strength

Tensile strength is measured with a tensometer. A tensometer is special machine that is designed to apply a tensional or compressive force to a specimen, in our case a die cut dumbbell shape, and measure how much force it takes to deform and fracture the specimen. The force is typically displayed on a stress-strain curve that shows how much force was required to stretch the specimen to deformation and ultimately break. 

Elongation

Maximum elongation, with respect to tensile testing, is the measure of how much a specimen stretches before it breaks. Elongation is usually expressed as a percentage. I had an application where a very small O-ring with an inside diameter of .056 inches had to stretch over a rod with a diameter of .170 inches. A Nitrile O-ring worked fine since it’s ultimate elongation was well over 400% and the O-ring was able to withstand the 200% stretch during installation. But when we tried to use a fluorocarbon compound several of the O-rings were breaking during installation. This fluorocarbon compound had an ultimate elongation of 150% and could not withstand being stretched to over 200% during the installation and the o-ring would break. 

Measuring Elongation

Elongation is measured with a ruler or an extensometer. An extensometer is an electronic ruler that is attached to the tensometer and will measure the extension of the specimen while torsional force is being applied. Another way of measuring elongation is with a regular ruler. To measure the elongation with a ruler, make two bench marks 1 inch a part on the specimen. This is the Initial Gage Length (Lo) and then measure the distance between the marks just before the specimen breaks. This is the Final Gage Length ( Lx). Calculate the elongation with the following equation: elongation % = 100( Lx – Lo ) / Lo. 

Tensile Set

While we are using bench marks, let quickly talk about Tensile Set. Tensile Set is the extension remaining after a specimen has been stretched and allowed to relax for a predefined period of time. Tensile Set is expressed as a percentage of the original length. Tensile set results are not found on the stress-strain curve. It’s a measurement that can be performed after the tensile strength test. Do not mistake Tensile Set with Elasticity. Elasticity is the mechanical property of a material to return to its original shape where Tensile Set is the amount on extension remaining after being stretched. 
 
A rubber band would have a low Tensile Set percentage. After stretched it relaxes close to, if not exactly to, its original length. Now take a piece of Teflon and stretch it. It does not return to its original length and it stays in its stretched state. This would have a high Tensile Set percentage. 
 
One test we perform in our Q.C. inspection is to pull on the O-ring and see how fast and how close it returns to its original diameter. The O-ring should fairly quickly return close to its original diameter. Often times a seal has to be stretched during installation and the last thing you want to happen is the O-ring stay stretched and not fit which could cause problems during assembly.

Measuring Tensile Set

Remember the 2 bench marks 1 inch apart on the specimen in the elongation test? To determine Tensile Set after break, wait 10 minutes after the specimen breaks and then fit the two halves of the specimen back together so there is good contact along the full length of the break. Measure the distance between the bench marks. Use the same equation used in the elongation test except the Final Gage Length (Lx) is the final measured distance between the bench marks. Another way to test without breaking is to stretch the specimen to a specified elongation and hold for 10 minutes. Release the specimen as quickly as possible, making sure not to allow it to snap back, and let sit for 10 minutes. Measure the distance between the bench marks. Again, use the same equation used in the elongation test except the Final Gage Length (Lx) is the final measured distance between the bench marks.

Compression Set

The purpose of the compression set test is to measure the ability of the rubber specimen to retain its elastic properties after compressive forces have been applied for a prolonged period of time at elevated temperatures. 
 
Compression set results can be useful to know when rubber seals, mounts or dampeners are subject to compressive forces in the application. This is particularly important when the seal is in a prolonged compressed state and even more so when simultaneously being exposed to elevated temperatures. When an O-ring is squeezed the rubber has elasticity. It wants to go back to its original shape. This elasticity is how the O-rings seals, especially under low or no pressure. When pressure is applied to the system the O-ring seal pushes against the groove wall opposite the direction of the pressure, forcing it to expand perpendicular to the direction it is being squeezed. This expansion provides additional sealing capability. 
 
When an O-ring is squeezed and subjected to excessive heat it can loose some or all of its elasticity and take a permanent set. Then, when you pull the o-ring out it no longer has a nice round cross section but instead has flat spots were it was squeezed in the application. This permanent set will reduce the sealing ability of the O-ring. The compression set test is a great way to see how the compound will react to compressive forces while subjected to heat. Also, poor compression set along with poor tensile strength can be an indication of the state of cure of the specimen. If you don’t cure the compound enough these properties will diminish.

How to Test Compression Set

The specimen, usually a molded rubber disk, is squeezed between two metal plates to about 75% of its original thickness and then placed in an oven at elevated temperatures for a period of time. After the specimen comes out of the oven and is allowed to cool, measurements can be taken and the percentage of original deflection is calculated. 
 
The original deflection is the amount you compressed the specimen in the fixture. If you have a 1 inch thick specimen and compress it to 0.750” thickness, the original deflection is 0.250”. Now lets say the 1 inch thick sample measured 0.875” thick after the test. It took a 0.125” set. 0.125 is 50% of the original deflection of 0.250” or a compression set of 50%. The higher the percentage the poorer the results. 
 
You may see “Method A” or “Method B”. Method A is compression set under a constant force and Method B is compression set under constant deflection. Method B is the primary method used throughout the ASTM D2000 specification. 

Compression-Deflection

The purpose of the compression-deflection test is to compare the stiffness of the rubber materials under a compressive force. This test can tell you how much a part will deflect under a given load or, alternatively, how much load it will take to deflect a part a given distance. Rubber mounts and dampeners are some examples of parts that are subject to compressive forces and knowing the relationship between compressive forces and deflection can be important.

How to Test Compression-Deflection

Compression-Deflection is measured on a compression testing machine or can be measured on any other type of machine that can apply a measurable force to a specimen at a given rate and be able to measure the deflection to one thousandths of an inch. At Hebei Shida Seal Group, our tensometer can apply compressive force at the specified rate and also measure the deflection. The test is performed by compressing the specimen to a specified compressive force and measuring the deflection results or compressing to a specified deflection and measuring the compression force results. 

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What is rubber blooming?

What is rubber blooming?

You may often ask “What is that white stuff on the surface of rubber parts.

Most EPDM and NBR rubber materials undergo a process called “blooming” when they are stored. “Bloom” is a milky dusting of dry powder on the surface of the rubber. Typically, this is caused by unused vulcanizing agent(s) migrating to the surface of the rubber part.

Will it affect my rubber part’s function?

Bloom is entirely superficial. If the gray color is not acceptable, wash the rubber part in water or light mineral oil to remove it. Since blooming is entirely normal and does not affect the function of a rubber part, it is not considered a defect. Likewise, it is not considered a contaminant in the rubber material.

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Hot Splicing / Vulcanizing

Splicing is a process where a material, usually an extrusion, is cut to length and bonded together to form an endless seal. Hebei Shida Seal Group utilizes both cold and hot vulcanization bonding techniques to produce spliced parts to customer specifications.
 
Uses the hot splicing/vulcanizing process to chemically bond two ends of a rubber extrusion together. By creating an endless seal, the rubber seal is more impermeable to the elements.  Hebei Shida Seal Group can vulcanize extruded rubber seals into circles and squares.
 
Luggage Weatherstrips
From vulcanized window seal, vulcanized frame seal, to spliced seals and vulcanized corners, we can manufacture the right endless rubber seal for your requirements.
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Rubber Compression and Injection Molding Process

The basic rubber molding processes we utilize are compression molding and injection molding.

Compression Molding:

Compression molding is a process that involves taking a rubber compound or mixed raw material and creating “pre-forms” in the basic shape of the end product. The pre-forms provide a surplus of material to be placed in the cavity, thus ensuring a total cavity fill. Once in place, the mold is then closed, applying both heat and pressure to the pre-form and allowing it to fill the cavity. When the cavity is filled, excess pre-form material spills out into overflow grooves. Following this step the rubber is then demolded, usually by hand, leaving us with the molded rubber product.

Compression Molding Diagram

Compression Molding Diagram

Compression molding is often chosen for medium hardness compounds in low volume production or in applications requiring particularly expensive materials. This process helps to minimize the amount of overflow, or flash created during the rubber molding process.

In creating compression molded rubber products, the pre-forms can be difficult to insert into more complex mold designs. Furthermore, the compression molding process does not lend itself well to the material flow requirement of harder rubber compounds.

Benefits of Compression Molding:

  • Cost effective tooling
  • Maximized cavity count
  • Economical process for medium precision

Compression molding can be a cost effective solution in situations where:

  1. The tooling already exists
  2. The cross-section of the part is very large and requires a long cure time

Applications of compression molding range from simple rubber grommets to complex air intake hoses, Hebei Shida Seal Group can offer a variety of other molded rubber products through compression molding.

Injection Molding:

This process is the most efficient way to mold rubber in most cases. Injection and injection-transfer molding start with more efficient material preparation. The material is mixed, typically in 500-pound batches, and then stripped immediately after being mixed, into continuous strips measuring approximately 1.25″ wide and 0.375″ thick. This strip is fed into a screw on the injection molding machines, which charges a barrel as needed with a pre-defined amount of material. When the mold is closed, the material in the barrel is injected into the mold cavities and cured.

Injection Molding Diagram

Injection Molding Diagram

Advantages of injection molding:

  1. The complete elimination of pre-forms
    • The production and need for pre-forms is a labor intensive step that can potentially affect the finished product through variability in pre-form weight and shape.
  2. Elimination of operator placement of pre-forms.
    • Since pre-forms are eliminated, the need for operators to place the pre-forms in a cavity (compression molding) or pot (transfer molding) is removed.
  3. Injection screw pre-heats material before forcing it into cavities
    • This process decreases the viscosity of the material, allowing it to flow more easily into the cavities.
    • This pre-heating provides the potential for decreased cure times through
      1. More rapid cavity filling due to lower viscosity
      2. Material already being in the curing process through the heat added during screw charging and shear created during injection
  4. Reduced cycle time
  5. Flashless tooling
  6. Economical process for high volumes of medium to high precision components
  7. Capable of producing overmolded components
  8. Minimal material waste

About us:

Hebei Shida Seal Group is an ISO/TS 16949 accredited manufacturer of molded rubber products and extruded rubber products from Hebei, China. We are tier-2 supplier to Hyundai and Kia. Look no future than Hebei Shida Seal Group if you need molded rubber products of high quality!

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Properties of Rubber Extrusions / Seals Tested

We test all materials and products to industrial, national standards and customer-specific requirements in-house or with third-parties. For example, we can test these properties of rubber extrusions / seals: hardness, density, tensile strength, elongation, brittleness temperature, heat aging, compression set, ozone resistance, staining in contact with organic material, corrosivity, low-temperature flexibility, low-temperature flexibility of coating, splice strength between solid &sponge, splice strength between extrusion and corner, dimensions, compression load, abrasion resistance of flock, insertion force, extraction force.

rubber seals test

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Types of Auto Weatherstrips – 2

According the characteristics, rubber weatherstrips for cars, trucks, and RV’s can be classified into two groups: dynamic seals and static seals.

1. Dynamic seals exist where there is relative motion between the mating surfaces being sealed. Typical dynamic seals include primary door seals(mounted on door), secondary door seal(mounted on body),hood/deck lid seals, trunk/tailgate seals, sunroof rubber seals, rocker seals.

dynamicseals

2. Static seals exist where there is no relative motion between the mating surfaces being sealed.Typical static seals include front and rear windshield weatherstrips, quarter window seals, window glass run channels, inner and outer belts & weatherstrips, etc.

About Us:
Hebei Shida Seal Group is located in Qinghe, Hebei, China, and is a Tier I supplier of dynamic and static rubber sealing weather-stripping to the automotive industry, and has attained TS 16949 designation. Main products are automotive body mounted sealing profiles & weatherstrips: EPDM rubber extrusion, sponge (cellular) rubber extrusion, flocked glass run channel, metal embedded and wire carries embedded rubber extrusion using latest curing system (microwave curing) .

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Rubber Molding Processes

Rubber Molding Processes

Processing rubber to produce final products for end use really depends on what the shape and product is. The main processes for shaping rubber are Extrusion, Compression Molding, Transfer Molding, and Injection Molding.

1. Rubber Extrusion

Extrusion is a continuous manufacturing process in which rubber is squeezed through a die and then vulcanized (industry terminology for cured). The die gives the extrudate its shape. The required pressure is produced via a conveying screw, in which the material is mixed, compressed and extruded through the die form to produce the final shape.

Extrusion Process Steps

  • The extrusion process begins with the unvulcanized (uncured) rubber compound being fed into the extruder.
  • Next, the flutes of the revolving screw will carry the rubber forward into the die, with an increase in pressure and temperature occurring as the material gets closer to the die itself.
  • Once it reaches the die, the built up pressure forces the material through the openings, where it will consequently swell in various degrees based on the material compound and hardness.
  • Because rubber has this tendency to swelling, many extruded parts require compensation on the cross sections of the die.
  • During the vulcanization (curing period), the extruded rubber will swell or shrink in both its cross section and its length depending on the type of rubber compound used.

2. Rubber Compression Molding

Compression molding is a process that involves taking a rubber compound or mixed raw material and creating “preforms” in the basic shape of the end product. The preforms provide a surplus of material to be placed in the cavity, thus ensuring a total cavity fill. Once in place, the mold is then closed, applying both heat and pressure to the preform and allowing it to fill the cavity. When the cavity is filled, excess preform material spills out into overflow grooves. Following this step the rubber is then demolded, usually by hand, leaving us with the molded rubber product.

Compression Molding Process Steps

  • Uncured rubber is preformed into a control weight, shape and specification.
  • Rubber preform is then placed into the mold cavity.
  • Rubber mold is then closed compressing the rubber to fill the molds cavities.
  • The mold remains closed under pressure and held at a temperature to allow the rubber to reach optimal cure.
  • Compressed rubber parts are then removed from the mold and the process is ready to begin again.

3. Rubber Injection Molding

Injection molding of rubber is based upon a process intended for the molding of plastics. Rubber injection molding successfully alters the plastics process by heating the rubber and placing it under significantly more pressure per square inch of cavity surface in molding. This is different from the plastic injection molding process where the materials are cooled under less pressure. Through various innovations, injection molding has become one of the most efficient ways to create molded rubber products in many cases particularly with more complex shapes.

The operation of an injection molding machine requires: feeding, mixing, and injection of a measured volume of compound, at a temperature close to the vulcanization temperature, into a closed and heated mold; a curing period; demolding; and, if necessary, mold cleaning and/or metal insertion (Overmolding process), before the cycle starts again. For maximum efficiency, as many of these elements as possible should be automated.

Injection Molding Process Steps

  • The uncured rubber is fed into the machine in the form of a continuous strip.
  • The uncured rubber is worked and warmed by the rotation of the screw in a temperature controlled barrel.
  • As the rubber stock accumulates in the front of the screw, the screw is forced backwards. When the screw has moved back to a specific point, this indicates the correct amount of rubber (shot amount) is ready for injection.
  • With the mold held closed under hydraulic pressure, the screw is pushed forward. This forces the rubber into the mold (this is the injection process).
  • While the rubber cures (vulcanizes) in the heated mold, the screw starts rotating and filling with the new rubber (the next shot).
  • The mold then opens and the part can be removed. The machine is ready to make the next shot as soon as the mold closes again.

About Us:
Hebei Shida Seal Group is located in Qinghe, Hebei, China, and is a Tier I supplier of molded rubber products to the automotive industry, and has attained TS 16949 designation. Main molded rubber products are rubber grommets, wire harness rubber parts, air intake hoses, rubber boots, rubber seals, rubber components, rubber diaphragms, rubber bumpers and stoppers using latest molding technology.