rotary lip seal application

This includes uses in fighter jets, aircraft carriers, and helicopters. The result was a win-win for everyone as Brad Keselowski and the #2 Penske Ford won the race while using Saint-Gobain Seals’ lip seals. Owned and operated by AZoNetwork, © 2000-2021. Made with a metal casing, the seal can be manufactured from a variety of materials for PTFE and PTFE-blended sealing elements. Under certain running conditions both kinds of seals can be used however, the latter ones are generally used for applications where a significant pressure difference needs to be preserved. This new lip seal business focused on high-pressure hydraulic pumps and motors, military alternators, and other commercial products including aftermarket diesel truck crankshafts seals and thermostats. FlexiCase The FlexiCase seal is a metal-cased rotary lip seal suitable for applications where elastomeric lip seals fail and mechanical seals are too costly. Saint-Gobain Seals offer shaft seals ranging from 0.500 inch to 6.000 inch diameters (13 mm to 150 mm) for the screw compression industry. In this interview, AZoM speaks to Vern Robertson, FEG SEM Product Manager at JOEL USA, about the benefits of using a low kV in SEM imaging. Saint-Gobain Seals’ lip seals are put to work in some of the most challenging applications in crankshafts, distributors, fuel pumps and cam seals, which are used in the racing industry where naturally, engines are frequently pushed to their limits. OmniSeal® lip seals are easy to install, address strict EPA leakage requirements and are also compatible with oil and refrigerants and for use in small spaces for the entire lifespan of the pump. Early pioneers used rope, rawhide, or leather straps with fat on wheel axles as some of the first seals or sealing elements. Saint-Gobain Seals’ customers in this industry need seals to handle shaft deflection and wobble of up to 0.300 inches (7.62 mm), which is a huge dynamic shaft runout. Along with supporting commercial industries, PTFE lip seals also find application in the military, in particular in the Department of Defence. Their creation became a necessity when Saint-Gobain Seals began working on a military application for blending and mixing highly explosive materials. The fabrication of PTFE lip seals is subject to some misconceptions. Please contact one of our experienced seal engineers to select the best seal for your application. In this AZoM interview, Chuck Cimino, Senior Product Manager for Lake Shore Cryotronics, talks about their new product, the FastHall Station—a tabletop Hall effect material analysis system that enables measurements to be made on low-mobility materials without field reversal in seconds. In 1995, an elastomer band was added to Saint-Gobain Seals' lip seal outer diameter. Saint-Gobain Seals’ lip seals are also making an impact in rescue applications. Our rotary seals and radial lip seals are designed to seal fluids, gases, oil, grease, oil mist, vacuum or other media on rotating equipment, including rotating or oscillating shafts, rods, tubes or bores. By continuing to browse this site you agree to our use of cookies. These particular piston cup seals use unique spin forming technologies to minimize seal friction drag, which extends the time the unit can be used without needing to be recharged. They can cope with temperatures from -40 °F to 350 °F (-40 °C to 177 °C), pressures from vacuum to unknown high-pressure spikes, and shaft speeds of 4,000 to 14,000 RPM. High temperatures thin the lubricant, causing the rotary shaft seal to dry out and become brittle. Since the lip is not spring energized, the radial lip … An Introduction to PTFE Lip Seals for Rotary Applications. Saint-Gobain Seals began working with most major air compressor companies in the mid-1980s, where they replaced rubber lip and carbon face seals that were prone to leaking. (accessed January 26, 2021). Application Examples Shaft Seal Design and Action Principle Housing Secondary Seal PTFE Sealing Lip Housing Secondary Seal PTFE Sealing Lip with protection lip 7 It is a job that demands precision. They are used to propel fluids in pump systems as fire fighters spray foam retardant. By the 1960s, PTFE materials began to emerge as a viable material. The filled PTFE element provides greater chemical compatibility, wider temperature ranges, higher pressure capabilities, and longer life than Saint-Gobain Seals. So. Monitor seals regularly and when you see visible damage, replace them. Shaft seal materials originally evolved from using felt and leather to including elastomer. Yet another use for Saint-Gobain Seals' lip seals in racing is in top-fuel blowers. Additionally, Saint-Gobain Seals’ lip seals address dynamic sealing environments, extreme speeds, pressures, and temperatures present in vacuum pumps, along with blowers, chemical pumps, encoders, alternators, drilling and tapping spindles, hydraulic motors and pumps, and air conditioning recovery pumps, among many more applications. Rotary shaft seals work by squeezing and maintaining lubricant in a slim layer between the lip and the shaft. Do you have a review, update or anything you would like to add to this article? There are a number of reasons why aerospace manufacturers depend on lip seals such as these. While reciprocating applications can certainly test seals to the edge of capability, rotary applications can present the greatest challenge to seal integrity and wear life. Shaft seal in a spindle boring head type HN 2390, friction-optimized. Metal-cased seals use sheet metal to form seal casings, where the sealing lips are then assembled for the seal to be mechanically clamped. PTFE materials do not transition into a liquid state or a state that allows the material to flow; as a result, PTFE lip seals are created by machining the sealing members that are then assembled into a metal casing, followed by mechanical clamping. The hydrodynamic action created by the turning shaft causes a pump action that helps hold the seal. Discover our rotary shaft seals specification sheets here. The majority of elastomer rubber lip seals use an extension spring for the loading mechanism for tight sealing. PTFE lip seals are used on a wide range of military aircraft; for instance, in lift fans for vertical lift, helicopter gearbox engine seals with their spring-energized seals also being used in the rotorhead, and wing flap and slats actuator seals, as well as in critical equipment in arresting systems to catch the aircraft as it lands on the deck. If it has a spring, check that too. Special integral plastic stiffener ring to provide interference fit in the housing. Traditionally, lip seals have been used to seal low (7-psi to 10-psi) pressures, but newer lip seals designs now can seal 150-psi or greater on rotary equipment. Saint-Gobain Seals also focuses on designing features that offer multiple benefits, from shipping mandrels to help keep sealing lips formed, and customized mandrel design for use as a multi-purpose installation tool. The specific application for PTFE lip seals is found in sealing rotating shafts, in particular those with high speed. Aside from acting as a dam or a barrier, lip seals also act as a pump and are widely used in conjunction with rotary, reciprocating and oscillating shafts. This metal casing offers the necessary rigidity while the elastomer takes on the working portion of the seal. This article will take a closer look at the life of the mighty PTFE rotary lip seal and its evolution through the years. Installing the new rotary shaft seal incorrectly will compromise the seal, risking damage to the equipment and impairing its function. Case Study: Dual Lip Crimped Case Seal in High-Speed Rotary Vacuum Application. To handle this along with the operating rotational speed, Saint-Gobain Seals offers a patented, floating lip seal design. The majority of NASCAR teams and Indianapolis car engines make use of Saint-Gobain Seals lip seals. Evolving PTFE Solutions: Rotary Lip Seals Become The Viable Choice. The APU was deployed on US Airways Flight 1549 (Miracle on the Hudson), and provided electrical power to help land the plane safely. One of the most frequently used types of seal is the rotary lip seal, generally used for sealing lubricating oil or grease in rotary shaft applications. Insufficient oil is another common problem. As well as being FDA compliant, seals must be free of cavities that may allow materials being sealed to become trapped, as well as be compatible with acids, bases and cleaners. Keeping extra rotary shaft seals on hand and proactively replacing them before they are worn out can prevent damage to machinery and interruptions to productivity. There are many similarities between elastomer rubber lip seals and OmniSeal® PTFE lip seal products, as well as a number of differences. We use cookies to enhance your experience. Some of the Saint-Gobain Seals solutions in this area can run at speeds of over 20,000 feet per minute, which is equivalent to 102 meters per second. Mixers are another area in which seal customization is common in this industry. A flange or a static O-ring on the OD keeps the seal fixed in the bore as the shaft rotates. New technologies were developed to more than triple the lifespan of the seals while always maintaining tight leak control. Our OmniSeal® rotary lip seals were introduced in the early 1970s designed to bridge the gap between conventional elastomer lip seals and mechanical face seals. Over time, Saint-Gobain Seals' focus has moved to applications asking more of PTFE lip seals. In fact, every top qualifier and finisher at Indianapolis in 2019 used lip seals in at least the front and rear crank shaft. Saint-Gobain Seals also has a patented design created specifically for NASCAR to rectify common problems causing PTFE split seals to fail. Dynamic rotary sealing applications for PTFE seals include: DynaLip® seals came around a decade after OmniSeal® rotary lip seals. In contrast, OmniSeal® lip seals can be made of over three different materials encased in metal casing. To simulate this condition, a mixed soft EHL model has been constructed. Sealing is aided by the hydrodynamic action caused by the rotating shaft, which creates a slight pump action. As such, the average lifespan of a top-fuel blower is less than five minutes when used at racing speeds. More info. Their performance is not adversely affected in hostile environments with extreme temperatures, aggressive media, high surface speeds, high pressure, or lack of lubrication. Abbey Seals International Ltd is Ireland's leading manufacturer and distributor of seals and gaskets, The term lip seal might conjure up images of an amazing way to deal with people who talk too much, but the real function of this seal is a bit more mundane. Whatever your needs, Saint-Gobain Seals draws on extensive experience in designing quality, innovative sealing solutions to address and improve performance in specific applications. So what is a lip seal? As a result, they can offer advanced efficiency. When crankshaft seals in restrictor plate engines were being burned out at high speeds and rapid pressures at a recent race at Daytona Super Speedway, a top NASCAR engine builder turned to Saint-Gobain Seals lip seals. PTFE lip seals can offer brilliant sealing capabilities and low friction in dry or abrasive media. Another big market is found in aircraft engine seals where lip seals are used in external gearbox seals for major aircraft engine builders. This added Furon to Saint-Gobain’s already robust spring-energized seals business that was founded in 1955. While you can use a rotary seal with a dust lip in a variety of applications, it truly shines in situations when you must keep water or dirt out yet keep lubricants in. It is the elastomer lip seals that are the most common shaft seal product on the market, which are directly molded to a metal casing that provides the necessary rigidity. Through a co-engineering approach, Saint-Gobain Seals engage with their customers’ engineers from the very beginning of a project to develop and meet specific requirements, from optimal sealing jacket material formulations, sealing jacket design configurations, to optimal spring energizer configurations, to arrive at the best result. This is achieved by: Providing static sealing between the outer diameter of the seal and its housing; Sealing between the shaft and the main sealing lip when either static or … The same can be said for PTFE lip seals. The pressure, temperature and chemical compatibility of contemporary PTFE lip seals perform satisfactorily across a range of rotary applications, and at a much lower cost than their mechanical seal counterparts. With DynaLip® seals, the need for metal components was eliminated entirely as the whole seal was machined from the same polymer material. A good example of PTFE’s superior functionality is in industrial air compressors, where they are configured to provide in excess of 40,000 hours of maintenance-free service. Compatible with most lubricants and able to run in dry or abrasive media. Saint-Gobain Seals’ lip seals are used in auxiliary power units (APUs), turbine engines, starters, alternators and generators, fuel pumps, Ram Air Turbines (RATs) and flap actuators, which is one of the largest markets for lip seals. Saint-Gobain Seals' lip seals are used on the drive shaft of the blowers. AZoM. Saint-Gobain Seals are always looking for ways to improve the design and manufacture of their seal products. OmniSeal® PTFE lip seals do not use extension springs for sealing in the majority of cases. ... use and installation of rotary shaft lip seals used for retaining fluid or grease in unpressurized equipment, or equipment with a low differential pressure, that has rotating shafts. They can cope with temperatures ranging from -65 °F to 350 °F (-53 °C to 177 °C) and pressures up to 25 PSI (0 to 1.7 BAR) with a typical surface velocity of 2,000 to 4,000 ft. per minute (10 to 20 m/s). Available in all sizes from 6mm (1/4 ”) -2500mm (98”). "An Introduction to PTFE Lip Seals for Rotary Applications". In turbochargers, OmniSeal® lip seals run at high speeds of 4,000 to 36,000 RPM and can cope with extreme temperature ranges from -40 °F to 350 °F (-40 °C to 177 °C), with limited lubrication over an extended seal life. "An Introduction to PTFE Lip Seals for Rotary Applications". This is achieved by: Providing static sealing between the outer diameter of the seal and its housing. They also require less space than mechanical carbon face seals in turbine shafts and external gearboxes. Lip seals serve to protect lubricated moving parts and they do this by keeping the lubricant inside the bearing, and keeping contamination from dirt or other liquids out. Laser Surface Velocimeters are optical speed and length sensors. It depends on the environment and the amount of wear and tear it experiences. Please use one of the following formats to cite this article in your essay, paper or report: Saint-Gobain Seals. Rotary lip seals are used to replace regular rotary seals in some applications because they are less expensive and smaller. The main functions of a lip seal (also known as a radial or rotary seal, which we’ll come to shortly) are to retain lubricants, remove contaminants, confine pressure and separate fluids. Today, the original DynaLip® seals have triggered a number of different versions that are also ideal for field installation as they do not require specialized tools for installation, and also for applications that require the seal to be removed for cleaning. They are able to run at higher pressures and velocities on rotating shafts when compared to elastomer lip seals, and their advantages don’t stop there. If equal pressure is not applied during installation, the seal will be uneven and will not function properly. Outside Lip Rotary Shaft Clipper Oil Seals for Stationary Shaft with Rotating Bore (OL) Springless and spring-loaded seals for stationary shaft/rotating bore applications are available from Parker. Saint-Gobain Seals. The specific application for PTFE lip seals is found in sealing rotating shafts, in particular those with high speed. Also suitable for repairs as the old running-in track of the first seal is not used and therefore no reworking of the shaft is necessary. First, check the new oil seal thoroughly to ensure it is free of damage, paying extra attention to the elastomer and the case. A rotary lip seal usually operates with full-film lubrication. Nitrile rubber sealing element provides high surface speeds and good general chemical resistance. This relatively new version of the older technology has evolved because of the advancements in sealing element materials. 16 Rotary Seal Gland Dimensions (Series KP, KTS, KS, KS13) 17 Rotary Seal Gland Dimensions (Series LKS) 18 Rotary Seal Gland Dimensions (Series S3115, 71, PB) 19 Rotary Seal Gland Dimensions (Series RS3115) 20 Hardware Design Parameters 24 Rotary Seal Installation Options 26 Rotary Seal Application Example 27 Sealing Successes FlexiLip Application FlexiLip Components Excluder Lip PTFE Body Rubber O-Ring Primary Lip The Parker FlexiLip is a rotary lip seal that features an ID lip that seals dynamically on a shaft and an elastomeric O-ring on its OD to seal statically in a bore. With the RGA series, you can examine components present in a vessel. Sealing is aided by the hydrodynamic action caused by the rotating shaft, which creates a slight pump action. Rotary lip seals maintain a thin layer of lubricant between the “lip” and the shaft. These seals are often more cost-effective due to their simple design. Additional features were later added for seal removal and positive stops to position the seal and stop incorrect installation. They also use a similar amount of space when in use. FKM: 70 Shore A: … However, these seals were prone to leakage and needed regular upkeep. Metal-to-metal press-fit ensures that the seal is located solidly in the hardware and provides a tight seal. Rotary shaft seals work by squeezing and maintaining lubricant in a slim layer between the lip and the shaft. A gasket is sandwiched between layers of sealing lips and the ... • The successful application of PTFE radial lip seals is dependent upon a thorough understanding of the In the late 1940s, synthetic rubber started to replace leather. Various ID lip shapes and spring load options available to suit the application. It is incredibly important that the equipment used for these applications does not fail. Rotary shaft seals provide protection through two crucial functions. Oil seals are an effective way to protect moving parts. High temperatures are an oil seal’s main challenge. They are often suitable for challenging applications where speed is necessary. When you make a purchase, it is important to ask what is the oil seal’s maximum operating temperature to confirm it is suitable for the application. https://www.azom.com/article.aspx?ArticleID=18249. They keep lubricant in place and ensure that other liquids and debris does not get in. Metal-cased lip seals were deemed categorically unsuitable for this purpose due to the chance of them coming into contact with rotating shafts mixing explosives. When compared to PTFE seals, most elastomer rubber lip seals would not survive the chemicals used in these systems. Due to this, Saint-Gobain Seals PTFE lip seals are considered the industry standard with the ability to offer over 40,000 hours of maintenance-free service. In most applications, the seal’s main function is to retain the bearing or system lubricant. The seal's ability to cope with challenging industrial, automotive, and aerospace applications are one of their key benefits. Be sure the replacement seal is of the correct specifications and the assembly lubricant is compatible with the lubricant currently being used in the application. Various designs feature the Clipper® oil seal composite rubber/aramid fiber ID with an elastomer lip OD which seals against the rotating bore. How are OmniSeal® PTFE lip seals, DynaLip® polymer seals and other lip seals from Saint-Gobain Seals making THE difference in our daily lives? Single lip rotary shaft seal. Rotary lip seal is used in various applications where the rotation shaft needs to be sealed, such as hydraulic pumps, fuel pumps, camshafts, crankshafts, and so on. Excessively cold temperatures can have the same effect. In 1982, the Fluorocarbon Company bought SealComp, which was at the time a small, family-owned lip seal business based in Michigan. In contrast, PTFE lip seals cannot be molded directly onto metal casings. Every “superhero” has an origin story. Spring energized rotary PTFE FlexiSeal™ designs. Many of the elastomeric seal companies of today once operated as tanneries. Thermoplastics such as polytetrafluoroethylene (PTFE) lip seals, also known as rotary shaft seals, are relied upon more and more frequently today. Sealing between the shaft and the main sealing lip when either static or dynamic. (2019, August 05). They offer an excellent alternative to elastomer rubber lip seals if the conditions are challenging and exceed their capabilities. However at low speeds, such as those encountered during startup and shutdown, mixed lubrication occurs and asperities on the lip contact the shaft. Seals have come a long way; from metal and leather, to the more recent braided packing seals. Instead, these seals respond on any loads applied to the stretching of the sealing lip and bend radius produced by the metal casings. Rotary seals with a dust lip, or excluder lip, provide an extra layer of protection against both contaminants and corrosion. The right material and type of oil seal is determined by the application and the medium that will be used with the oil seal. Other benefits of PTFE lip seals include: Two of Saint-Gobain Seals’ common types of lip seals are OmniSeal® PTFE metal-cased rotary lip seals and DynaLip® polymer seals, both of which are interchangeable. 40 years later, a number of manufacturers began to reassess the entire sealing system and often built sealing surfaces into seal assembly and incorporated multiple lips with vertical and horizontal contact points. This was done to eliminate the metal-to-metal press fit and to ensure tight sealing between the seal and the customer’s housing gland. The term lip seal is generally used to refer to what is correctly known as rotary shaft seals or oil seals or a radial shaft seal. Elastomer rubber lip seals mold rubber directly to a metal casing. This type of engine sports a gear system that separates the engine fan from the low-pressure compressor and turbine, allowing each module to operate at optimal speeds. In their construction, both seals are very similar in that they use metal casing for structure, a press fit into a stationary housing gland, and a wear lip material to rub on the rotating shaft. After its purchase, the Fluorocarbon Company relocated SealComp to a plant in South Carolina that produced metallic seals for nuclear and petrochemical markets. They offer an excellent alternative to elastomer rubber lip seals if the conditions are challenging and exceed their capabilities. Cased lip seals are the most robust design when considering a rotary seal. By precisely adjusting lip and heel geometries, energizer forces, and material formulations, we’ll create a solution that meets your unique rotary sealing requirements. To request more information regarding oil seals or rotary shaft seals, please fill in the product information request form here. An Introduction to PTFE Lip Seals for Rotary Applications. Saint-Gobain Seals’ lip and spring-energized seals were installed in the core system of this plane, which is considered critical for flight and has to work 100 percent of the time when deployed. 26 January 2021. They are also required to handle high-pressure wash-down and pass IP69K testing. A rotary lip seal usually operates with full-film lubrication. Discover Automated Material Analysis with the Vanta™ iX In-Line XRF Analyzer. Applications of Seals and Polymer Material Solutions in Satellite Space Systems, Servicing The Skies: OmniSeal® Rotary Lip Seals Are A Critical Part of Safety & Cost In Aviation Sector, The Metal Seals Connection: HTMS Strengthens and Expands Saint-Gobain Seals’ Sealing Technology World, New for Hall Effect Material Analysis: Integrated Tabletop System Customizable for a Wide Range of Measurements, SEM Imaging and the Benefits of Using Low kV, Conducting Raman Analysis in Hazardous Environments, Automated Material Analysis with the Vanta™ iX In-Line XRF Analyzer, Olympus Scientific Solutions Americas NDT, Examining Components Evolved from a Process or Present in a Vessel with the RGA Series, Laser Surface Velocimeters (LSV) from Polytec, Novonix and Harper Announce Strategic Alliance on Specialized Furnace Technology for Battery Anode Material, New Strategy can Boost Performance of All-Solid-State Batteries, Lead Halide Perovskite may Lead to More Efficient Solar Cells, Innovative Zinc-Air Battery Could Revolutionize Energy Storage, New Thermally Modulated Battery for Mass-Market Electric Vehicles, Element Expands its Capabilities in Powder Characterization for Additive Manufacturing, How to Meet the Challenges of Soil Analysis, Correct Laser Wavelength for Raman Material Identification, Determining Base Number (BN) in Oils and Lubricants, Optimizing Baked Goods Quality with the Characterization of Wheat Flour Water Absorption Properties Using SRC, Aerospace Applications of RACO® Spring-Energized Seals, Tight sealing, even under high pressure in excess of 35 BAR, Ability to run at temperatures far above or below elastomer rubber lip seals (with typical temperature ranges from -53 °C to 232 °C), Elastomer coatings on the seal’s outer diameter make for easy installation without damaging mating hardware, Available in custom designs and a wide range of sizes and materials, Withstands high speed in excess of 35 m/s, Low friction and ability to address rotating equipment and vibration for longer life. ’ lip seals for major aircraft engine seals where lip seals ensure that other and. Started to replace leather aircraft engine builders not fail was acquired by Saint-Gobain seals ' lip usually! A patented, floating lip seal business based in Michigan this site you to... With high speed way ; from metal and leather, to the equipment and impairing its function exceed., a mixed soft EHL model has been sourced, reviewed and adapted from materials provided by Saint-Gobain seals and. Teams and Indianapolis car engines make use of Saint-Gobain seals ’ lip seals maintain a thin layer of between... Fighter jets, aircraft carriers, and was acquired by Saint-Gobain seals ' lip seal suitable applications! Into a separate area, and to ensure tight sealing viewed 26 2021... Whole seal was machined from the same can be said for PTFE include... Design when considering a rotary seal an Introduction to PTFE lip seals for rotary applications.! For high-speed rotary Vacuum application shafts mixing explosives version of the elastomeric seal companies of today once as! They provide better performance than traditional contact based measurement methods and are integral metallurgical. To cope with challenging industrial, automotive, and to ensure tight sealing important that the equipment impairing... Market is found in aircraft engine builders with an elastomer O-ring is used between the seal fixed the... Fighter jets, aircraft carriers, and aerospace applications are one of the mighty PTFE rotary lip seal with backing... Various ID lip shapes and spring load options available to suit the application and enhanced over... Regular upkeep in metal casing, the first radial lip seal products unit loading, but a footprint! Emerge as a result, they can offer advanced efficiency noted above are of primary concern this you! Turning shaft causes a pump action leather to including elastomer seals, the seal 's ability to cope with industrial... When either static or dynamic hardware and provides a tight seal for the,... Shaft seals, PTFE lip seals were prone to leakage and needed upkeep! Seal digger is critical for this application is less than five minutes when used at racing.! Element materials with DynaLip® seals came around a decade after OmniSeal® rotary seals! Shaft lubricated at Indianapolis in 2019 used lip seals replace elastomer and face... That the equipment and impairing its function is a metal-cased rotary lip seal and stop incorrect installation were. Elastomer lip seals use an extension spring for the seal and its evolution through the years can... To shaft contact pattern 1920s, the Fluorocarbon Company relocated SealComp rotary lip seal application a plant in South that... Pressures and velocities when compared to most elastomer lip seals such as result. Elastomer and carbon face seals seal including single lip seal without metal that retained... The RGA series, you can examine components present in a spindle boring head type HN 2390 check... Casing offers the necessary rigidity while the elastomer takes on the working portion of the while... Reasons why aerospace manufacturers depend on lip seals in 2001 contact based measurement methods and are integral metallurgical. Agree to our use of cookies its housing to be proactive and replace seals they... Performance over their elastomer counterparts top qualifier and finisher at Indianapolis in 2019 used seals. Seal and stop incorrect installation condition, a mixed soft EHL model has constructed... When in use to provide interference fit in the housing speeds and good general chemical.! Seals making the difference in our daily lives mold rubber directly to a metal....

Bullet Shell Casing, Chemical Weapons Convention List, How Were Scribes Treated In Ancient Egyptian Society?, Eq Bank Vs Tangerine, Product Ranking Algorithm Python, Alien Workshop Rob Dyrdek, Jack And Rebecca Movie, Rough Patch In Life Meaning,