Use the durometer chart below to help you narrow down your shore hardness requirements. (Powders and moulding compounds), Used mostly as wood adhesives for the bonding of plywood and particleboards, concerns about the release of formaldehyde into the atmosphere have led to it being substituted by other adhesives, e.g. Removal of residual molecules under vacuum and solidification at approximately 140C. For this test, ASTM D785-08 (2008) and ASTM E 18-11 (2011) methods can be applied for measuring the hardness. polypropylene properties and their values, Detailed Property Comparision: PP Impact Copolymer, PP Copolymer and PP Homopolymer, Watch free video tutorial to improve PP cycle time and limit part shrinkage, View all PP Grades Suitable for Injection Molding , View all PP Grades Suitable for Extrusion , View all PP Grades Suitable for 3D Printing , Be the first to comment on "The Definitive Guide to Polypropylene (PP)", Get more information about polymer properties here , Learn more about the benefits and applications scope now , new additives, polymerization processes and blending solutions, Check out PP grades with various conversion mode here , Explore several nucleated PP grades here . Hapco is proud to be celebrating 50 years in business. The unit Pascal is used for hardness, but it's very different from pressure. only. These cookies track visitors across websites and collect information to provide customized ads. British Standard 903 (1950, 1957), Methods of testing vulcanised rubber Part 19 (1950) and Part A7 (1957). What factors affect the hardness of the material? The most used hardness scales are Shore, using a carbide tungsten indenter (ball, cone or frustum) with specific testing loads and the IRHD (and Micro IRHD) using a ball indenter, a clamping system with defined hole and a specified testing load . cereal packaging and packs for cold meats, cheeses. Tech Tip For O&P FabricatorsHomopolymer recommended oven temperatures are 325Fto 350F. The hardness value is read directly from the durometer scale. So without further ado, lets get started. Hanover, MA 02339, Phone:(781) 826-8801 $(document).ready(function() {
Rockwell Hardness A specimen of at least 1/4 inch (6.35 mm) thickness is indented by a hard steel ball and the depth of indentation is measured. Decorative laminates, laminating resins, surface coatings, buttons, dinner ware, tanning of leathers. xref
The Shore D hardness test, aka the durometer test, came into existence so people could have a common reference when discussing materials. For Rockwell hardness test in samples of PE composites, a total of 10 indentation points can be measured on the samples' surface. Data and information contained in the Polymer Selector In laymans terms, a durometer is a dimensions measurement. The Shore A scale uses a blunt indenter with a moderate spring force. It has good chemical resistance and weldability, which makes it ideal for the automotive industry, consumer goods, furniture market, and industrial applications such as custom wire baskets. 0000001064 00000 n
Shore Hardness is measured using a device called a Durometer. $('#fieldblock-message').css('clear','both');
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These techniques provide a corresponding ranking of the hardness of two polymers. There are over 85 thousand types of injection molding plastic materials to choose from, but that doesn't mean picking just the right material is impossible. The term polymer comes from the Greek words "poly" meaning many and "mer" meaning units. This linear hydrocarbon resin is the lightest polymer among all commodity plastics. Some common uses of polypropylene include: Some of the polypropylene structure and material properties that you should know when choosing a coating for your custom wire basket include: An ideal use case for polypropylene would be an aqueous parts washing process where the basket being coated would be submerged in non-oxidizing agents for prolonged periods of time. The MatWeb Material Property database has records of 55,468 polymers. You also have the option to opt-out of these cookies. The resulting penetration is dependent on the following factors: Fascinating Read What is Processing and Drying Temperatures of Plastics. Shore hardness (analog here) ISO 7619-1, ISO 868, ASTM D2240 Shore hardness to ISO 7619-1, ASTM D2240 and ISO 868 is a test method that can be easily performed with a portable hardness tester. as binding specifications. It enables it to withstand plastic deformation, penetration, scratching, and indentation; hence, hardness is significant for determining specific material applications, pros, and cons from an engineering standpoint. How additives help improve PP properties? Analyzing hardness parameters is seen in mostly industrial parts and construction devices. Shore hardness is often used as an indication of flexibility or stiffness, which is called flexural modulus. The higher the number harder the material. Bowling balls, buttons, resin component of GRP, used for boat hulls, canoes, car and lorry body panels, embedding, coating. Injection moulding. Material for testing needs to be in laboratory climate storage at least one hour before testing. Polypropylene is easy to decorate withtransfer patterns for O&P applications. 0000001244 00000 n
Seal-peel or easy-open packaging, e.g. Due to polypropylene structures rigidity and relative cheapness, its used in various applications. 0000002584 00000 n
1 Polypropylene (Shore Hardness D: 70) $ 39.00 - $ 1,479.00 These Polypropylene cutting boards have a Shore Hardness D rating of 70, which ensures a perfect blend of softness to ease wear and tear on your steel rule blade, while being resilient enough to guarantee a long life. Custom sizes and colors available upon request. This linear hydrocarbon resin is the lightest polymer among all commodity plastics. Soft, flexible, lightweight plastic material that is easy to fabricate and form. This website uses cookies to improve your experience while you navigate through the website. Hello mates, today Im going to talk about a very intriguing topic, the hardness of plastic materials. The tensile strength of a TPE material, which measures it's resistance to breaking under stress, is also directly related to hardness within a TPE family. Shore hardness scales simplify comparisons between materials that can otherwise be difficult to compare directly. S However, within a TPE family there exists a direct relationship between these properties; as hardness increases, so does flexural modulus. | The Definitive Guide, What is Anionic Polymerization? 40 top 10 injection molding machine manufacturers in china, Top 10 Plastic Injection Molding Companies In United States, Top 6 injection Molding Machine Manufacturers, Top 10 Injection Moulding Companies In UK 2022. There are different Shore Hardness scales for measuring the hardness of different materials. phenolics, http://www.matweb.com
Force is 1kg +0.1kg for Shore A, and 5kg +0.5kg for Shore D. Calibration of the Durometer is one per week with elastomer blocks of different hardness. Learns and shares consistently about plastics technologies. With more than 50 years of experience, our ISO 9001 certified organization is dedicated to providing quality urethane and epoxy materials to meet your needs. Plastic and rubber materials have many useful physical and mechanical properties, but it can be challenging to select the right material for a specific project. 17 0 obj<>
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Extracting a product with a harder durometer reading would likely result in breakage. TPEs can even be used to absorb energy in acoustic or vibrational dampening applications. http://www.prospector.ides.com
2648 Merchant DriveBaltimore, MD 21230-3307. Get Traffic & Exposure. The slower, the better. Homopolymer Polypropylene (Polypro)Homopolymer polypropylene is stronger and stiffer than copolymer. polydimethylsiloxane, polybutadiene, polyisoprene or poly (ethylene-propylene)) Thermoplastic Styrenic Block Copolymers (SBC or TPE-S) The test is mainly utilized when the materials are too soft for the Rockwell test. The best way to examine hardness would be consulting your industry experts, literature references for the relevant vertical or region."}}]}. Fax:(781) 826-9544, Business Hours:Mon.-Thurs. What is recommended as a compound to pour over this capital and also hold the concrete poured into it. The higher the number harder the material. Several tests are used to determine the hardness of polymers including: The ultimate tensile strength of a plastic (or any other material) is the tensile (tension) force require to break it. Polypropylene is not recommended for any high-temperature processes because of its low melting point. Snack food packages, cereal box liners, wrapping, refuse sacks, carrier bags, industrial liners, freezer bags, water pipes. A is a hard thermoplastic at room temperature but soften at elevated temperatures (e.g. at A wiser choice would be a Shore 30A material that will offer enough flexibility to remove the part easily. That question doesnt have a definitive answer; however, there is a direction I can suggest you go when choosing what method and what scale is best for your industry and product. There are several scales made for discussing different materials. Materials with a very soft texture, like rubber and TPE, should be tested with Shore D. There are three most popular Shore hardness scales: Shore 00 Used for measuring gels and rubbers that are very soft in nature. Have a technical question? xb```"V ~g`0pt0410^5^b1(Vj)$dHL15. i Vbc`gQ`p`/ The Rockwell hardness tests harder materials like polycarbonate, polystyrene, and polyamide. The material under test should be a minimum of 6mm (0.25inches) thick. Below 20C, polypropylene embrittles. Low cost, chemical resistant plastic with excellent aesthetic qualities. It enables it to withstand plastic deformation, penetration, scratching, and indentation; hence, hardness is significant for determining the applications, pros, and cons of specific material from an engineering standpoint. 0000002009 00000 n
The cookie is used to store the user consent for the cookies in the category "Other. Strong, stiff, versatile low cost plastic material that is easy to fabricate, bond, and weld. Curbell supplies fabricated and machined plastic parts manufactured via CNC routing, milling, vacuum forming, die cutting, and more. PP comes either as a homopolymer or as a copolymer and can be greatly boosted with additives. It comes at the high end of the softer materials, making it semi-rigid. After some time, the pre-stressing is still registered the remaining indentation is read from the scale. = Rockwell hardness is generally chosen for 'harder' plastics such as nylon, polycarbonate, polystyrene, and acetal. The Rockwell hardness is usually chosen for "harder" plastics. As you can see from the graphic, there is overlap on the different scales. It is made from propene (or propylene) monomer. Melting waste plastic to 250C to get rid of contaminants. Once the needle is pierced as far as it can be, the depth of indentation of the needle is measured, which is proportional to the hardness of the plastic. Rockwell hardness is used to compare the hardness of metals but there are Rockwell hardness scales suitable for the harder plastics such as polycarbonate (PC), nylon (PA) and acetal (POM). In yield and tensile strength, a plus-minus linear correlation is observed (The flowing image will make it more clear). [3] Theoretical background of the test is considered in Stoprobleme in Physik, Technik und Medizin by Grundlagen und Anwendungen[4], The ASTM D2240 standard recognizes twelve different durometer scales using combinations of specific spring forces and indentor configurations. Enter custom cuts or cut-to-size when ordering. The tensile force is measured in either pounds per square inch (psi) or megapascals (MPa). Shore hardness measures the hardness of a material by determining its resistance to indentation. Rockwell M 18 - 99
Marlin Steel is a leading manufacturer of customengineered products from steel wire We use the durometer hardness scalealso known as the Shore hardness scaleto help you determine the best molding materials for your project. Superior strength in engineering applications (vs. 4657. The basic test requires applying the force in a consistent manner, without shock, and measuring the hardness (depth of the indentation). {\displaystyle S=100} However, an important factor to note is that the hardness is not always a good indicator of other properties like abrasion to wear, strength, and scratch resistance and hence, should not be considered alone for product design. By assessing the hardness of materials at various stages of the manufacturing process, they can detect any variations and make appropriate adjustments to sustain consistent quality. The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is used to store the user consent for the cookies in the category "Analytics". If a timed hardness is desired, force is applied for the required time and then read. | The Definitive Guide, Food Grade Plastic: The Best Plastics for Food Applications, What is Condensation Polymerization? The standard test specimen for ASTM D2240 is 64 x 12.7 x 3.2 mm (2 x x 1/8 inch). Nylon fibres are used in textiles, fishing lines, carpets, upholstery fabrics, seat belts, toothbrush bristles, ropes. 100 HWMoFW cAp==0dGJ*)fIrL*\*oY}CiY.5SlYH4+V al*\gXx\;\1sT1B[!/{^K. Let's look in detail at plastic hardness testing.You'll discover the shore (durometer) hardness test (or rockwell hardness test) which is commonly used to me. The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". To illustrate, we can compare common objects and materials that exhibit similar hardness. the specific gravity of a polymer = density of polymer. Telephone handsets, suitcases, kitchen appliance housings, handles, computer cases. Alternative to glass, used as windows, screens, vehicle signal lights, lenses, light fittings, signs, adhesives. ","acceptedAnswer":{"@type":"Answer","text":"Hardness is dependent on plasticity, strain, strength, toughness, viscosity, viscoelasticity."}}]}. To answer that question, its important to know about your process! to be accurate and correspond to the best of our knowledge, they are provided without Nylon 6/6 (Polyamide) Products > Plastic Stock Shapes > Nylon 6/6 (Polyamide) Nylon 6/6 is the extrusion grade of the Nylon family of solid polymer shapes. Shore Durometers Hardness Range Shore durometers come in a variety of hardness ranges. Shore hardness is measured using a Durometer, so the result of the test is also known as the Durometer hardness. Hard elastomeric urethane tooling materials range in hardness from Shore A 90 to Shore D 60, and are work horse metal forming materials. Inserting clarifiers into PP enables it to match PET's transparency. the optimal processing temperature for line bending a thermoplastic polymer will be different to the optimal processing temperature for extruding or injection moulding it.
The scale operates within a numeric range of 00 to 100, with 00 being the softest material and 100 being the hardest. A vast range of polymer solutions means each customer receives the best fit for their needs. Durable, versatile, low cost, abrasion and chemically resistant plastic material. Hapco's employees are knowledgeable and ready to help. Do you have any questions about measuring hardness or about TPEs in general? How to compare between the main PP types? {"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"Which are the two main methods to measure plastic's hardness? Hardness - Introduction; Hardness Shore D; HDT @0.46 Mpa (67 psi) Heat Deflection Temperature of Plastics; Hardness Rockwell M; Haze; HDT @1.8 Mpa (264 psi) M. Max Continuous Service Temperature; Modulus of Elasticity; Min Continuous Service Temperature; S. Shrinkage; Stiffness; Strength at Yield (Tensile) Durometer measurement scales range from 0 to 100, but there is no such thing as a durometer unit of measurement. Mechanical Properties of Plastic Materials Material Formula Abrasive resistance - ASTM D1044 mg/1000 cycles Coefficient of . Materials like plastics, rubbers, and elastomers are rated on the Shore D scale for hardness. Shore hardness measures are dimensionless, which comes between 0 to 100. Basic Scheme of Shore Durometer (Source: Springer) What does the depth of penetration depend on? Toys, rigid packaging, refrigerator trays, costume jewellery, lighting diffusers, cassette and CD cases, storm windows, disposable medical ware. These resistance values can be found using a durometer, which measures the hardness of plastics, silicone, rubber, and other polymers and elastomers on a standardized scale to ensure that the material has the right amount of flexibility or hardness. but departs from experimental data for http://www.indianplasticportal.com, Copyright Laszlo Lipot: Multimedia Design and Technology Education
Is a polypropylene coating right for your custom wire basket or tray? trailer
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Shoes, hammer heads, skate board wheels, synthetic leather fabrics. 0000000984 00000 n
I was just wondering if there is a certain range of Shore A hardness that is best for different types of plastics. 0000014885 00000 n
Different types of hardness have different scales for measurement. Another great example of that same phenomenon is seen in the case of manufacturing a gasket for a high-pressure application, the manufacturer would require a material with a higher Shore hardness to withstand the pressure and avoid any leaks. Shore Hardness (Shore D) ISO 868 70 Table 3. DSM's material portfolio meets strict medical industry requirements. On the other hand, the Shore method is used for testing elastomers, rubbers, and softer materials like polypropylene, polyethylene, polyvinyl chloride, etc. "}},{"@type":"Question","name":"Why is hardness in plastics so important? Extruded pipes for water, gas, corrugated pipes and conduit for electrical cables, wire and cable insulation. Polypropylene is a material that is frequently compared to PVC (polyvinyl chloride). Any suggestions? A typical speed for flexible filaments is usually 20 mm/s, the maximal recommended speed is somewhere between 30 and 40 mm/s. // ]]>. This cookie is set by GDPR Cookie Consent plugin. I hope you like my piece. ","acceptedAnswer":{"@type":"Answer","text":"The Shore D hardness test, aka the durometer test, came into existence so people can have a common reference when discussing materials. http://www.design-and-technology-education.com
Polypropylene (PP) is one of the most versatile polymers widely used in packaging, textiles, automotive, and electrical applications. startxref
Variations in the properties of a polymer are made by varying the polymerisation process and by changing the composition of the polymer, e.g. The Shore A Hardness Scale measures the hardness of flexible mold rubbers that range in hardness from very soft and flexible, to medium and somewhat flexible, to hard with almost no flexibility at all. It has been commercially available since 1948; developed by Dupont. Solid tyres, wheels, shoe heels, automobile bumpers. It offers a comprehensive snapshot that makes it one of the most valuable plastics and rubber hardness scales available. The Shore durometer is a device for measuring the hardness of a material, typically of polymers.[1]. from assessments of our experts. New polymers are being developed all the time. Hardness - Rockwell -1 Izod impact strengt h J m-1 Poisson's ratio Tear strength N mm Tensile modulus GPa Copolymer polypropylene tends to have better stress crack resistance and low temperature toughness than homopolymer polypropylene. You can read more about him at About me page. One polymer may have different processing temperatures for each manufacturing process, e.g. Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. However, the ASTM D2240-00 testing standard calls for a total of 12 scales, depending on the intended use: types A, B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R. Each scale results in a value between 0 and 100, with higher values indicating a harder material. hi, i want to make a mold of a roman temple of the winds capital which sets on my concrete columns. We carry an extensive inventory of plastic sheets, rods, tubes, film, tapes, adhesives and more from highly qualified manufacturers. 2023 Curbell Plastics, Inc. All rights reserved. %%EOF
polystyrene, polyethylene, or polypropylene) B is a soft elastomer (e.g. Sandwich bags, films, sheets, cling wrap, car covers, squeeze bottles, toys, houseware, carrier bags, rubbish sacks, packaging, gas and water pipes, liners for tanks and ponds, moisture barriers, in construction, cable and wire insulation, used for rotational moulding. Send me an email. Shore A, D and Rockwell Values of Different Plastics Materials (Source: ScienceDirect), ABS/PC Blend - Acrylonitrile Butadiene Styrene/Polycarbonate Blend, ASA/PC Blend - Acrylonitrile Styrene Acrylate/Polycarbonate Blend, Ionomer (Ethylene-Methyl Acrylate Copolymer), Deliver medical devices trusted by patients and professionals, Develop strong and durable automotive parts with flat glass fibers. It is sensitive to microbial attacks, such as bacteria and mold. On the other hand, shore D is preferred when testing hard rubbers, semi-rigid plastics, and hard plastics. The major difference between the Shore A hardness scale and Shore D is that the former measures softer rubbers (including thermoplastic rubber). Curbell Plastics Polypropylene Data Sheet, Curbell Plastics Chemical Resistance Chart, Rchling Polystone G HDPE & Polystone P Polypropylene. Resin Shortage and Supply Chain Disruptions, Filters: A Key Tool in the Fight Against Covid-19, Casting a Clear Sculpture Using Hapco Materials, Equipment, and Expertise Part 2, Shore hardness is an important consideration. Fashion and footwear, packaging, cling film, credit cards and synthetic leather, wire insulation, floor covering, roofing membranes, shower curtains, table covers, stationary, automotive seat coverings, upholstery sheets, wall covering, garden hoses, handbags, inflatable boats and toys, rainwear, tubes, automotive pedals and trim,
What are the commercially available PP grades? As a manufacturer, one needs to understand that material with specific hardness for your application. The R designation is applicable to any D2240 Type, with the exception of Type M; the R designation is expressed as Type xR, where x is the D2240 type, e.g., aR, dR, etc. Learns and shares consistently about plastics technologies. Cost advantage in blow molding bottles (vs. neat or reinforced with cheap mineral fillers, short or long glass fibers, natural fibers or even self-reinforced. The table below provides details for each of these types, with the exception of Type R.[5], Note: Type R is a designation, rather than a true "type". Polypropylene is a thermoplastic that is manufactured through the polymerization or combination of propylene monomers. More Efficiency. We work closely with our customers to determine the perfect durometer hardness as well as other physical and mechanical characteristics for particular components and applications. Now, the question is, how seamlessly will you be able to remove the original model from the mold once it is cured? Melamine-Phenolic Copolymer moulding compound. Lower numbers indicate less resistance and softer materials. FDA compliantpolypropylene grades are available. How PP challenges polyethylene terephthalate (PET)? Hardness of the samples was tested using a Shore Type D CV durometer according to ASTM D2240. We help brands optimize their online presence & performance. Polypropylene has excellent fatigue resistance, but it is also used for many single-use plastic applications, such as food packaging. | Mechanical Properties | Special Properties | Types of Plastics. Several verifiable hardness scales have been developed to test and analyze hardness. Shore hardness values range typically from 45A to 45D. acrylic, polythene and nylon, have at some point been soft and have been shaped and moulded. Higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. "}},{"@type":"Question","name":"Which device is used to measure Shore hardness? < Lower numbers indicate less resistance and softer materials. That was my take on the Shore hardness scale and all its attributes. Copolymer recommended oven temperatures are 300F to 350F. Polypropylene used in the manufacturing ofupper and lower extremity orthoses and prostheticsoffers the O&P fabricator a material that is easy to drape, blister form and seam. Mold shrinkage lies between 1.5 and 3%. As the density of water at 4C is 0.9999 g/cc and at 30C is 0.9956 g/cc, it is so close to 1 through a range of temperatures that for practical purposes, it may be counted as 1. The Rockwell hardness tests harder materials like polycarbonate, polystyrene, and polyamide. It is 200 times stronger than glass and is warranted against cracks and breakage. Indentation Hardness (Shore) Resistance of a material to deformation. Density of a polymer = Mass of polymer Volume of polymer, expressed as grams per cubic centimetre (g/cc). 0000000016 00000 n
Besides being susceptible to impacts and scratches, polypropylene has poor resistance to UV and its heat- aging stability can be adversely affected by contact with metals. Cant find what you need? Such materials are also less prone to deformation under pressure or stress, thus ensuring consistent performance over extended periods. the Polymer Selector including but not limited to material suitability, material Polypropylene can be manufactured using blow molding, injection molding, and extrusion. The hardness of plastics is an important factor to consider when selecting materials for various applications. Rubber stamps are most common materisl to have 50 Shore A hardness. <<91bd0c0a21c5e94eb7a02e91d1612b75>]>>
What are the test methods to measure Shore D Hardness? Used in many of the same applications as homopolymer polypropylene, but where slightly more flexibility is needed. Shore D Utilized to measure the hardness of semi-rigid plastics, hard rubbers, and hard plastics. Today, Hapco has established itself as an industry leading partner for some of the worlds most reputable companies. Onthe other hand, the Shore method is used for testing elastomers, rubbers, and softer materials like polypropylene, polyethylene, polyvinyl chloride, etc. Therefore, the units are not suitable for direct comparison. Additionally, polypropylene is dense enough to make it nearly impervious to water. Nucleators can speed up crystal formation in PP during cooling. Always go for a reliable hardness test depending on your material, which will help make good products and save time and money. ","acceptedAnswer":{"@type":"Answer","text":"Shore and Rockwell methods are the most popular methods for measuring plastic's hardness. The cookie is used to store the user consent for the cookies in the category "Performance". You can use the durometer chart below to get a rough feel for different Shore D hardness values. To measure different categories of materials, there are three main Shore hardness scales: Shore hardness scales offer easily quantified hardness levels. Since a polypropylene structure will absorb shock rather than redistribute it, a polymer-coated basket would be ideal for processing delicate parts such as glass tubes or crystal components. [8], Another relation that fits the experimental data slightly better is[9], A first-order estimate of the relation between ASTM D2240 type D hardness (for a conical indenter with a 15 half-cone angle) and the elastic modulus of the material being tested is[10], Another Neo-Hookean linear relation between the ASTM D2240 hardness value and material elastic modulus has the form[10]. Which device is used to measure Shore hardness? Introduction. The A scale is for softer ones, while the D scale is for harder ones. Understanding these factors can help engineers and designers choose the right plastic for their specific applications. Toll Free:(877)-729-4272 This thereby shortens cycle times, and sometimes also improves clarity as well. One property that varies inversely with hardness is coefficient of friction. The best way to examine hardness would be to consult your industry experts and literature references for the relevant vertical or region. A spring-loaded needle is kept under the plastic in Shore hardness, and pressure is registered. [1] Higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. By clicking Accept, you consent to the use of all the cookies. Thermal insulation materials, packaging, impact protection and cushioning, drinks cups, food trays, clam shell packaging. While not quite as soft as some formulations of PVC, polypropylene is still a semi-soft material that will absorb impactshelping minimize the risk of parts getting scratched during the agitation cycle of many aqueous-based cleaning processes.
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