HIGH-SOLIDS COATINGS THE IMPACT OF MATERIALS AND SPEEDS ON PISTON PUMP CONFIGURATION PISTON PUMP PROBLEM SOLVER High-Soild Coatings Material Impact
PISTON PUMP PROBLEM SOLVER High-Soild Coatings Material Impact Finishing With one-coat coverage and minimal or no solvent use, high-solids coatings reduce labor costs and health, safety, and environmental risks Paints Coatings High-solids coating application systems are now being used across many different finishing, painting, and coating applications in industry, construction, and transportation. Many of these new coating systems, which minimize the use of environmentally toxic solvents, rely on reciprocating piston pumps to move high-solids mixtures (often containing either 80/20 solids/solvent content or fully 100% solids content) at high pressures through the application system In addition to minimizing or eliminating the health, safety, and environmental risks of toxic solvents, also known as volatile organic compounds (VOCs), high-solids coating systems offer other benefits. They eliminate the added labor costs required to apply additional topcoats in traditional finishes due to the evaporation loss of solvent during the drying process, which reduces the thickness of conventionally applied coatings after drying. Because high-solids coatings consist mostly of the coating material itself and use little or no solvent, these coatings also produce a far more consistent surface finish, with no thickness variation between angled and flat areas of the work surface. This advantage makes high-solids application an ideal method for products, parts, or work surfaces requiring coating layers having precisely-measured thicknesses. 2 AROzone.com High-Solid Coatings Material
These advantages have popularized high-solids coating systems across a wide variety of industrial applications, such as in shipbuilding, bridge building, pipefitting, and also in automotive, aviation, and general manufacturing applications. Shipbuilding Bridge Building Pipe Fitting Manufacturing High-Solid Coatings Material AROzone.com 3
ABRASIVE PROPERTIES Fillers Used in High Solids Coatings Cause Excessive Wear on Key Internal Piston Pump Components The materials used in high-solids coatings present challenges to OEMs when designing application systems to handle these new paint, coating, and finishing materials. For example, high-solids coatings contain pigments, resins, and other filler materials with abrasive properties, like talc, which is used to improve surface adhesion and workability of coatings. When transferred at pressure and continuous speed through the piston pump, even the smallest abrasion effect of these materials is magnified significantly, and can lead to excessive wear on critical, unprotected internal pump components, such as packings, seals, plungers, and cylinders. In fact, high-solids coatings are often more abrasive than many other types of materials commonly processed in fluid transfer operations. Fillers used in high-solids coatings are some of the most abrasive materials found in fluid transfer operations 4 AROzone.com High-Solid Coatings Material
FAILURE POINTS OF PUMP COMPONENTS In High-Solids Coatings Applications If the material composition of internal pump parts is not engineered to resist the abrasive action of these coatings, and with the multiplier effect of continuous motion and fluid pressure, over time, the abrasive filler materials will grind against the packings, plunger, and cylinder areas of the pump lower assembly, causing scoring of packing seals and galling on cylinder walls. Continuous speed and pressure flow of high-solids coating fluid multiplies the abrasive effect of fillers used in these materials, leading to premature wear and reduced service life on improperly configured piston pumps Pump manufacturers, such as ARO, have spent many years researching the effects of virtually all chemical ingredients and compounds on every critical component of their products, and should be consulted by OEM builders for specific pump configuration advice early in their system design process During normal operation, abrasive wear on improperly-specified internal pump components leads to a number of problems: For example, these abrasive fillers may damage the upper and lower packing seals and score the plunger, which reduces pump efficiency and could eventually create a leak path in the pump lower assembly, or cause total pump failure by allowing for coating material to migrate into the air motor. For the customer, the cost impact of abrasion wear can be serious, evidenced by shorter intervals for required service, production down time, emergency service, and shortened pump life. These increased service and failure risks require OEM system builders who design and specify spray systems for high-solids coatings applications to be acutely aware of the potential for abrasion wear on piston pumps, lines, regulators, filters, nozzles, and all other in-line components of the system. The first step in configuring the right pump for the application is for OEM system builders to carefully evaluate the properties of the specific high-solids coating being used by their customer for their application by referencing the SDS data sheet. This analysis, done in consultation with the pump manufacturer s technical team, will identify abrasive, corrosive, reactive, or other chemical properties that require pump components specifically designed to resist the effects of these materials. High-Solid Coatings Material AROzone.com 5
OPTIMIZE MATERIAL TYPES Resist Abrasive Wear in Critical Pump Components Pump packing seals and plungers are a particular area of concern when handling abrasive materials in pumps for high-solids coatings applications. Upper and lower packings, available in leather, are highly resistant to abrasive scoring that causes fluid leakage between the upper or lower packings and the plunger or cylinder wall. Depending on the chemical properties of the specific type of filler or other component being used in the coating formulation, packings made from EPR (ethylene propylene rubber), UHWM-PE (ultra-high molecular weight polyethylene), or polyurethane may also be suitable materials for use as packing seals based on the specific coating to be applied in the system. Heat treatment of metal components, such as plungers and cylinders, also resists ongoing abrasive wear. Depending on the properties of the material being used in the customer s specific coating application, abrasion-resistant plungers and cylinders, available in hardened carbon or stainless steel, or hard chrome-plated steel, enhance pump reliability and performance, reduce maintenance costs, and extend service life. In some applications, especially when coating materials may also have corrosive properties, ceramic coated internal parts can provide additional protection for key pump components. In addition to internal pump components, any in-line component that comes into contact with the coating material at speed and pressure must be designed for abrasion-resistant use. Nylon hoses work well for abrasive applications and in-line components such as regulators and filters made from hardened carbon, tungsten carbide, or stainless steel, also offer the best abrasion resistance. 6 AROzone.com High-Solid Coatings Material
SPECIFY A CORRECTLY-SIZED PUMP Avoid Material Separation in High-Solids Coatings and Maximize Pump Service Life Regardless of the brand or manufacturer of the pump being used, to maximize piston pump performance and service life, select a pump that can meet your system s fluid delivery requirements without running continuously at its maximum cycle rate Speed is another very important consideration when configuring pumps for use in high-solids coatings applications, and one which is especially important for these types of materials. By specifying a pump that can operate at the correct speed, and not at an overly fast cycle rate, OEMs can avoid material separation in the coating during application. Also, a pump that must continuously run at its maximum cycle rate in order to provide the fluid transfer rate needed for the application will require more frequent service and will ultimately have a shorter operating life. This applies to any piston pump produced by any manufacturer. Using a smaller pump that must operate at a higher cycle rate to generate an adequate flow rate for the application also risks damage to the coating material. This is due to shear, which is caused by agitation of the material at higher speeds inside the pump, where the solids separate from the solvent used in the coating. If material separation occurs, the result is uneven coverage of the coating and poor finish quality. Overspec the piston pump to operate below its peak cycle rate for your specific OEM application. To prevent material separation in coatings applications, and to reduce service costs and maximize long-term service life for the pump, select a pump that is capable of meeting your system s fluid delivery requirements at a rate which is below its fully rated speed in cycles per minute. For example, if a transfer rate of 5 GPM is required for the application, specifying a pump with a 10 GPM transfer rate will allow this pump to run continuously below its maximum cycle rate, extending its service life. This approach results in the best overall combination of low ongoing service costs, longer service intervals, and longer operating lifetime for the pump used in the application system. High-Solid Coatings Material AROzone.com 7
PLURAL COMPONENT AND AIR-ASSIST COATING SYSTEMS Two-part, or plural component, systems, are also used in many high-solids coatings applications. Plural component systems feed two (or more) different types of materials through the application system, such as in epoxy finishes, where individual resin and catalyst fluids are pumped from different containers and mixed at the end of the nozzle just before they are applied to the work surface. In these cases, it is best to specify piston pumps explicitly designed for plural-component high-solids finishing systems. Typically, these consist of a pump with a single air motor and two pump lower assemblies, where the air motor drives a piston for each lower assembly, to transfer each component material through its own separate delivery line to the mixing end at the nozzle. These systems may deliver each coating component at a 1:1 ratio, or in unequal ratios. These ratios can be changed in the system s configuration, either by using separate pumps, each having its own displacement rate, or by placing an in-line regulator to reduce the delivery rate for one component of the system. In addition to flow control, some plural component systems utilize air-assist atomization, where an additional air line is integrated into the system to atomize the component mixture at the end of the applicator nozzle as the material is being applied to the workpiece. 8 AROzone.com High-Solid Coatings Material
EARLY FOCUS ON SPECIFIC HIGH-SOLIDS COATINGS AND APPLICATION SPEED By focusing on the unique properties of the specific high-solids coating material being used by your customer, selecting a pump that delivers the correct delivery rate, and working with your pump supplier to configure the internal components of the pump to maximize reliability and service life, you can reduce your customer s operating costs on your system and avoid expensive production downtime due to unscheduled service calls. Selecting the right pump for your system, early in your system design and configuration process, eliminates these future problems and allows you to focus on delivering the highest-quality application High-Solid Coatings Material AROzone.com 9
PISTON PUMP OVERVIEW For over 85 years, the ARO Fluid Products business of Ingersoll Rand has developed partnerships with more than 200 original equipment manufacturers and distributors, enabling us to better focus on the unique pumping needs of many industries. It s a strategic merger of our partners application expertise, along with our decades-long legacy of designing and building outstanding piston pumps. Simply Versatile ARO piston pumps are capable of handling a wide variety of viscous fluids. With a wide selection of pressure ratios and displacement rates available, ARO offers a number of piston pump packages that can meet your specific application needs. Offered in multiple configurations, including single-post, two-post and heavy-duty two-post. Our partnerships create unmatched application expertise in: z Finishing z Coatings z Sealants and adhesives z Lubrication z Bulk material transfer and circulation z High-pressure cleaning Finishing Coatings Sealants and Adhesives Lubrication Bulk Material Transfer and Circulation High-Pressure Cleaning 10 AROzone.com High-Solid Coatings Material
Distributed by: www.arozone.com arotechsupport@irco.com youtube.com/aropumps (800) 495-0276 ARO is a brand of Ingersoll Rand. Ingersoll Rand (NYSE:IR) advances the quality of life by creating comfortable, sustainable and efficient environments. Our people and our family of brands including Club Car, Ingersoll Rand, Thermo King and Trane work together to enhance the quality and comfort of air in homes and buildings; transport and protect food and perishables; and increase industrial productivity and efficiency. We are a $13 billion global business committed to a world of sustainable progress and enduring results. For more information, visit www.ingersollrand.com. We are committed to using environmentally conscious print practices 2016 Ingersoll Rand IRITS-1016-186