RDI - PTFE Hydraulic Rod Seal with NBR/FKM O-Ring

 Which material is better for O-rings? This is because many customers do not know what material O-rings should be used for their machinery. In fact, this is easy to do: 1.Natural rubber NR (Natural Rubber) is made from latex collected from rubber trees and is a polymer of isoprene. It has good wear resistance, high elasticity, tear strength and elongation. It is easy to age in the air, becomes sticky when exposed to heat, easily expands and dissolves in mineral oil or gasoline, and is resistant to alkali but not strong acid. • It is a raw material for making tapes, hoses, and rubber shoes. It is also suitable for making shock-absorbing parts and products used in liquids containing hydroxide radicals such as automobile brake fluid and ethanol. 2.Styrene-butadiene rubber S B R (Styrene Butadiene Copolyme) is a copolymer of butadiene and styrene. Compared with natural rubber, it has uniform quality and less foreign matter, but its mechanical strength is weaker. It can be blended with natural rubber. advantage: • Low cost non-oil resistant material • Good water resistance, hardness below 70 with good elasticity • Poor compression deflection at high hardness • Can use most neutral chemicals and dry and nourishing organic ketones shortcoming: • It is not recommended to use strong acids, ozone, oils, esters, fats and most hydrocarbons. • Widely used in tire industry, shoe industry, cloth industry and conveyor belt industry. 3.Butyl rubber IIR (Butyl Rubber) is the polymerization of isobutylene and a small amount of isoprenes. It retains a small amount of unsaturated groups for sulfur addition. Because the methyl group has less steric hindrance to the movement of molecules than other polymers, it has less gas permeability and is resistant to heat and It has high resistance to sunlight and ozone, and good electrical insulation; it has high resistance to polar solvents such as alcohols, ketones, and esters. The general operating temperature range is -54~110 ℃. advantage: • Impermeable to most common gases • Good resistance to sunlight and ozone • Can be exposed to animal or vegetable oils or oxidizable chemicals shortcoming: • Not recommended for simultaneous use with petroleum solvents, gum kerosene and aromatic hydrogen. • Used to make rubber parts resistant to chemicals and vacuum equipment. 4.Hydrogenated nitrile rubber HNBR (Hydrogenate Nitrile) Hydrogenated nitrile rubber is a nitrile rubber that has been hydrogenated to remove part of the double chains. After hydrogenation, its temperature resistance and weather resistance are much higher than that of ordinary nitrile rubber, and its oil resistance is similar to that of ordinary nitrile rubber. The general operating temperature range is -25~150 ℃. advantage: • Better wear resistance than nitrile rubber • Excellent corrosion resistance, tensile resistance, tear resistance and compression distortion properties • Good resistance to ozone, sunlight and other atmospheric conditions • Generally suitable for use in laundry or dishwashing detergents shortcoming: • Not recommended for use in alcohols, esters or aromatic solutions. • Air-conditioning and refrigeration industry, widely used as seals in environmentally friendly refrigerant R134a systems. • Automotive engine system seals. 5. EPDM (Ethylene propylene Rubber) is a copolymer of ethylene and propylene with no double-stranded main chain. Therefore, it has excellent heat resistance, aging resistance, ozone resistance, and stability, but it cannot be vulcanized with sulfur. In order to solve this problem, a small amount of a double-stranded third component is introduced into the EP main chain and sulfur is added to form EPDM. The general operating temperature range is -50~150°C. Excellent resistance to polar solvents such as alcohols, ketones, glycols and phosphate ester hydraulic oils. advantage: • Good weather resistance and ozone resistance • Excellent water and chemical resistance • Alcohols and ketones can be used • Resistant to high temperature vapor and has good impermeability to gases shortcoming: • Not recommended for food use or exposure to aromatic hydrogen. • Seals for high temperature water vapor environments. • Plumbing fixture seals or parts. • Rubber parts in brake (brake) systems. • Seals in radiators (car radiators). 6.NBR (Nitrile Rubber) is copolymerized by acrylonitrile and butadiene. The acrylonitrile content ranges from 18% to 50%. The higher the acrylonitrile content, the better the resistance to petrochemical hydrocarbon fuel oil, but the low temperature performance is Deterioration, the general operating temperature range is -25~100 ℃. NBR is one of the most commonly used rubbers for oil seals and O-rings. advantage: • It has good properties of oil resistance, water resistance, solvent resistance and high pressure oil resistance. • It has good compression distortion, wear resistance and elongation strength. shortcoming: • Not suitable for use in polar solvents such as ketones, ozone, nitrohydrocarbons, MEK and chloroform. • Used to make fuel tanks, lubricating oil tanks, and rubber parts used in fluid media such as petroleum-based hydraulic oil, gasoline, water, silicone grease, silicone oil, diester-based lubricating oil, glycol-based hydraulic oil, etc., especially sealing parts . It can be said to be the most widely used and lowest-cost rubber seal at present.

The purpose and material selection of Guide strips导向带的用途和材质选用 DMS Seals Technology Co., Limited specializes in the production of various types of seals and has extensive experience in the design, production and use of seals. Customers often ask about the performance and use of seals. Let me introduce them to you now. What are Guide strips:         Guide strips are strips that guide moving parts. Its main function is guidance. In order to realize this function of guidance, it must support the guided part and guide and correct its movement trajectory. In order to realize the function of the guide well, it also requires isolation, shock absorption and noise reduction of the guide parts. Guide strips are mainly used in oil cylinders and cylinders. Due to their excellent performance, they are also widely used in other motion mechanisms. 1. Main requirements: 1）Support and positioning: Provide radial support and motion positioning to the piston and piston rod in the cylinder barrel. 2） Isolation: Isolate the two pairs of moving pairs, the piston and the cylinder barrel, the piston rod and the guide sleeve, to prevent direct scratches, wear and strain between the moving pairs. Especially when the moving pairs are all made of steel, they must be isolated, otherwise they will be easily injured. 3） Friction reduction: Guide strips also play an important role in reducing friction and friction work between moving parts, reducing ineffective work and heat. 4） Vibration absorption and noise reduction to reduce system operation vibration and noise 2. Materials:         It is mainly filled with tetrafluoroethylene and phenolic cloth, and a very small amount of polyformaldehyde, nylon and soft metal are also used. 3. Use:         Supplied in roll or split ring form. The open ring shape can be installed and used directly. The roll shape must be cut when used. The cutting length must be calculated in advance: there can only be one opening. The opening form is a 45° inclined opening. The opening distance is about 3-15mm, or the diameter of the guide ring. 3-5%.         Generally, the openings are inclined openings. Straight openings or Z-shaped openings are rare, and they all have specific uses and purposes. The purpose of the opening is two-fold. First, it is to facilitate installation. If there is no opening, it will be a whole ring, which is difficult or impossible to install, so the opening must be made. Secondly, the opening should be opened with a certain opening distance to facilitate the automatic coordination of volume changes. Otherwise, the movement may be stuck or the moving parts may be strained due to excessive volume expansion of the guide strip under certain conditions. Rolled ones are relatively cheap, and the same rolled material can be used to make guide rings of different sizes. （1） Phenolic cloth is generally in the shape of an open ring, and a small amount is in the shape of a roll. （2）PTFE is generally in roll shape, and a small amount is in open ring shape.4. Production method:         Extrusion method (low cost, large batch size) and cutting and shaping method (high cost, small batch size, flexible production, many styles) 5. Carrying capacity:         Varies depending on the hardness of the material. The general phenolic cloth is hard and has a large load-bearing capacity, while the PTFE-filled cloth is softer and has a smaller load-bearing capacity. 6. Operating temperature:         Generally, the operating temperature range of phenolic cloth is -40 ~ 120 ℃. Those filled with PTFE can be used at -200~200℃, but the load-bearing capacity decreases as the temperature increases.7. Life span:         Phenolic cloth guide strips are prone to physical aging at higher temperatures (greater than 80°C) and in certain working media. The material gradually becomes hard and brittle, and finally cracks and scratches the working surface. Teflon guide tape does not have similar problems. 8. Friction coefficient:         The dry friction coefficient between PTFE guide strip and steel is 2-10%, and the wet friction coefficient is 0.1-4%. The dry friction coefficient between phenolic cloth and steel is 20-40%, and the wet friction coefficient is 10-20%. 9. Media resistance:         Teflon is resistant to all working media, while phenolic cloth is not resistant to working media containing water or brake oil. 10. Dirt holding capacity:          The PTFE guide strip has excellent dirt-holding capacity and can block dirt in the working medium for the main seal and prevent damage to the main seal. Generally, when a phenolic cloth guide strip is installed, a tetrafluoroethylene guide strip must be installed, the purpose of which is to block dirt. 11. Running speed:         The PTFE guide strip can be used in extremely high-speed or extremely low-speed cylinders. The phenolic cloth guide strip has a large friction coefficient, so the effect is not ideal at extremely high speeds or extremely low speeds. 12. Application:        The phenolic cloth guide strip has strong load-bearing capacity. This guide strip must be installed for cylinders with large eccentric load, such as various heavy-duty cylinders, high-pressure cylinders, and large cylinders.        The PTFE guide strip has a small friction coefficient and strong dirt-holding capacity. It is actually used in all types of oil cylinders, especially high-speed oil cylinders, high-efficiency, low-friction oil cylinders, and various engineering machinery oil cylinders. 13. Notes on use:         Rolled guide strips are generally cut as needed before installation. When cutting, two issues need to be paid attention to: angle and length. The angle should be guaranteed to be around 45°, and the length should ensure that the opening size meets the standard.         In a word, if the load capacity is the main consideration, it is recommended to give priority to phenolic cloth guide strips, and in all other cases, priority is given to filled PTFE guide strips.

Polychlorotrifluoroethylene (PCTFE) seal product introduction聚三氟氯乙烯（PCTFE）密封件产品介绍Overview: PCTFE has excellent rigidity, low temperature resistance, and cold flow resistance. It is an ideal sealing material under low temperature and high pressure conditions and has special uses in high-tech fields. application: 1. High molecular weight PCTFE is white powder or granules. It is commonly used in contact with strong corrosive media, sealing and gasket materials for ultra-low temperature and high-pressure systems, transparent materials for observation windows, electrical insulation materials, etc. 2. Low molecular weight PCTFE is liquid or waxy and is used as sealing fluid, grease for highly corrosive media and balancing fluid for navigation gyros. Specification: The company produces PCTFE rods, pipes and related products of various specifications. Product specifications can be customized according to customer service requirements.

On Women’s Day on 3.8, DMS SEALS distributes benefits to female employees3.8妇女节，达曼森密封为在职女员工派发福利啦 March 8th is International Women's Day, also known as March 8th Day, Women's Day, and March 8th International Women's Day. It is a festival for women around the world to fight for peace, equality, and development. For a century, women in various countries have made unremitting efforts to fight for their rights.     March 8, 1911 was the first International Women's Day.  China began to commemorate the March 8th Day in 1922. The first mass event for Chinese women to commemorate the March 8th Day was held in Guangzhou in 1924. In December 1949, the Government Affairs Council of the Central People's Government designated March 8 every year as Women's Day. In 1977, the General Assembly passed a resolution requesting each country to select a day of the year as the United Nations Women's Rights and World Peace Day in accordance with its own history and national traditions and customs. International Women's Day is celebrated on March 8th.         On March 8th, in order to thank female employees for their hard work, DMS SEALS distributed red envelopes to female employees as a Queen's benefit for March 8th Women's Day. It also allowed female employees to dress up freely on the holiday without having to wear work clothes and celebrate the holiday beautifully. I wish the goddesses happiness and good health, and I also wish DMS SEALS gets better and better!