Products
Solutions
|
|
You are here: Knowledge Base > Information Guides
|
General advice for handling Cyanoacrylates adhesives Last Updated: 26/01/2012 |
|
Cyanoacrylates are used in ... Ammunitions Appliances Automotive Components Batteries Consumer Products Cosmetic Containers Electronics Loudspeakers Medical Devices Writing Instruments Thousands of tons of cyanoacrylate are sold each year. Much of this cyanoacrylate is destined to become waste due to improper handling and application techniques. The good news is ADL dispensers and valve systems provide precise control of cyanoacrylate application � efficiently, without the waste, mess, and hazards of alternative devices (squeeze tubes and bottles, sticks). When using an ADL system, the benefits to the customer are: Better quality Reduced fluid use�typically by 65% Less downtime Minimal maintenance Improved operator safety The information contained in this guide booklet is written to help you develop confidence setting up ADL cyanoacrylate dispensing systems and to provide beneficial support for customers with cyanoacrylate applications. Background What are cyanoacrylates? Cyanoacrylates, also known as instant adhesives, crazy glues, CAs or super glues, are moisture-cure adhesives usually having a rapid curing time. How do cyanoacrylates work? Unlike other adhesives, the curing reaction occurs without the need for heat, presses or catalysts. Curing is based on the presence of moisture. Note: Humidity is sufficient to start the reaction. This curing reaction creates the bond. Note: The strongest bond is created with a minimal amount of cyanoacrylate. �Less is better� is the way to think about cyanoacrylate deposits. Precise, accurate deposits give the customer control over cure time and bond strength. The main challenge when dispensing cyanoacrylates is to prevent premature curing. Unwanted moisture MUST be kept away from the cyanoacrylate process. Moisture can originate from a number of sources: humid air, skin perspiration, condensation on refrigerated adhesive or components, use of moisture-absorbing nylon fittings and factory compressed air systems. Remember: 1. Keep moisture out. 2. Less application of cyanoacrylate gives a stronger bond. Carefully control the size of the cyanoacrylate deposit. 3. Avoid metal components. The only exception is passivated stainless steel. * Wetted surfaces (parts that contact the cyanoacrylate) are best when made of polypropylene (PP) or polyethylene (PE) or Teflon (PTFE). Passivated stainless steel is generally suitable for cyanoacrylate dispensing. Passivation is an acid etching process that strips free iron from the surface of stainless steel (free iron deposits are the result of machining and drawing processes). Free iron on the surface of stainless steel can react with cyanoacrylate and cause clogging. Why use ADL dispensing equipment? Productivity gains It is possible to double output, while maintaining and even increasing the quality of parts. How this works�doubled output does not mean working twice as fast or twice as hard. Doubled output comes from working smarter�increasing the yield of each production run and each hour of production time. The application is cleaner with ADL products. This means less time and cost for cleanup. Rejects due to misapplied fluid are eliminated using EFD dispensing equipment. Consistency and reliability in deposit size leads to constant curing times. The safety time to guarantee a completed cure is cut to a minimum. The product is transferred faster to the next stage in the assembly process and production bottlenecks are eliminated. Overall, production is more efficient when using ADL dispensing equipment. Fluid savings Typically, customers that use ADL dispensing systems experience fluid savings of 60% or more. The savings build from several areas: 1. No wasteful over-deposits. Human nature is that if a �little bit is good, a lot must be better.� This is wasteful for production quality, especially with cyanoacrylates. 2. When dispensing with the 700 series system, all cyanoacrylate in the barrel is used. (Premature curing frequently occurs inside the squeeze bottle. The bottle is then discarded only partially used.) 3. Eliminating rejects saves the fluid that would have been used to build the reject parts. 4. When using the valve system, the fluid can be fed directly from the 500 gram standard bottle without any transfer. Eliminate skin problems from contact with fluids When working with cyanoacrylates, skin contact should be avoided. This is easy with ADL equipment. ADL systems safely contain the cyanoacrylate, making it less likely for operators to come in contact with the adhesive. Less skin contact, less risk !! Higher quality � reduced costs from rejects and rework Customers using ADL dispensing systems enjoy consistent, high quality output. This cuts costs and reduces labor time from rejects and rework. (The actual saved costs depend on the rework time or, more likely, the cost of the part that needs to be discarded.) Reasons for higher quality products with ADL equipment: 1. Precise deposit control ensures the best cure times and stronger bonds. 2. Controlled, closed system prevents contamination of the cyanoacrylate and avoids messy workstations. 3. Better product appearance through precise application. 4. High quality through repeatable and reliable deposit sizes � even with different assembly operators. The final cyanoacrylate dot applied to the right spot. Just imagine throwing a part away that is nearly finished � the costs can be significant. ADL is an established expert and partner in fluid dispensing systems - Sales Specialists understand the needs of cyanoacrylate users and offer experienced advice in dealing with these high performance adhesives. - High quality performance products. - Orders are shipped within 48 hours. - Helpful, prompt customer support. Q & A 1. What tips should be used? The tip selection is based on the application. Note: where possible, it is best to use an all-plastic tip. Teflon-lined tips (5121TLCS, 5125TLCS) do not react with the cyanoacrylate and resist clogging. These tips are usually best for small deposits of low viscosity cyanoacrylates. If a larger deposit is needed, use any of the flexible polypropylene tips. Semi-rigid Teflon tips are premium components with see-thru shafts for fluid flow. In 0.5" and 2" lengths with colour coded double helix locking polypro hubs (TF22-2, TF16-1/2, TF18-1/2, TF22-1/2, etc) Flexible PP or PPS tips offer excellent performance with cyanoacrylates. Tip hubs are molded of inert polypropylene. Shafts are made of inert polypropylene. They can be used for medium to low viscosity cyanoacrylates on sensitive work surfaces or to easily drag around the edge of a part (short polypropylene tip PPS-style) or to deposit cyanoacrylate into deep recesses (long, flexible polypropylene tip PP-style). In applications where a rigid shaft is preferred, general purpose TE tips can offer good performance. Shafts are made of passivated, burr-free 304 stainless steel. Passivation strips free iron from the surface; this avoids an early reaction with the cyanoacrylate. For microdots, use stainless steel tips (30 gauge or 32 gauge). Tapered TTN tips offer smooth flow of adhesive through the tip and all plastic construction to prevent reaction with the cyanoacrylate. Use the tapered tips for gel cyanoacrylates when using TS255 dispenser, or for any cyanoacrylate when using an ADL Dispense Valve System. 2. How are cyanoacrylates typically packaged? 500 gram or (1-lb bottle), 20 gram or 50 gram squeeze bottle or gel tube. For specific questions on cyanoacrylate, contact the manufacturer. For questions on dispensing, contact us! Dos and Dont's - Avoid moisture. Use only clean, dry, compressed air. Compressed air is a prime source of moisture. Install and maintain an air dryer on compressed air supply. - Use the 5 micron air filter to remove moisture from plant air lines. - Monitor the bowl of the 5 micron air filter for accumulated water. - To prevent curing of the cyanoacrylate in the dispense system, use only polypropylene, polyethylene, or Teflon parts. Can the components be reused? While it might seem cheaper to reuse components, don�t. Here�s why: � Cyanoacrylate is easily contaminated. � Tight tolerances on the piston and barrel can be distorted. � Unnecessary labour costs are involved in cleaning. � �Fuss factor� decreases productivity. � Skin contact with the acetone is dangerous. � Solvent disposal costs are high. Fresh, new components are the only economical and safe solution. How to handle the equipment during short breaks, shift changes, overnight, over weekends, or longer breaks When not using the dispenser, set the barrel into the barrel stand. Put 100% fresh acetone into a catch bottle below to prevent the tip from drying up. For an expected downtime exceeding more than 1/2 hour, close the safety clip and install a tip cap. Use a 7016TC tip shield over the tip if left for short periods. This covers the tip itself. Dispensing cyanoacrylates with the Valve System When cyanoacrylate is applied within an automated manufacturing process and large amounts (typically more than 7 oz. per day) are used, the TS5622VU valve system provides trouble-free deposit control. When large amounts are dispensed manually by an operator, the hand-lever dispense valve (TS5623HU) is a good solution. Why is the Valve System ideal for dispensing cyanoacrylates? The TS5622VU diaphragm valve combined with the TS500R controllers is the most cost effective dispense valve system for controlled, reliable dispensing of cyanoacrylate adhesives. Note: The hand-lever dispense valve offers similar features for manual application of stripes or �by eye� deposit control. The valve controller: TS500R has a programmable time function that allows for exact, repeatable output, easy purge when changing to a new bottle of adhesive, simplifies initial valve setup and allows for fast on-the-fly valve adjustment. The reservoir: The cavity for the TS1215 tank is designed to accept standard 500 gram bottles of cyanoacrylate. This simplifies refilling and reduces handling. Air Source Plant air can be contaminated with moisture, particularly problematic in hot, humid climates. The inlet air to the TS5622VU valve needs to be clean and dry. Whenever plant air is used, be sure to install the TSD800-6FR 5 micron air filter. This filter removes remaining moisture from the air supply. If available, nitrogen gas is an excellent pressure source for system operation. Nitrogen is an inert gas and will not introduce moisture contaminants into the cyanoacrylate. Cyanoacrylate Reservoir A variety of reservoir options is available. ADL barrel reservoirs, cartridge assemblies, 1-litre and 5-litre tanks can be used to supply cyanoacrylate to the TS5622VU valve. To choose the best reservoir for the application, determine how much cyanoacrylate will be used in 8 hours. If this amount is unknown, make the best guess based on the deposit size required and the number of parts to be produced. Often the best reservoir to use is our TS1215 tank. The tank provides easy access for refill and/or purging. Top porting allows a user to feed fluid directly from a 500 gram size bottle. Some gel cyanoacrylates are packaged in 10.3 ounce (310ml) caulking tubes. Our TS918-110 caulking cartridge assembly is an excellent reservoir system to feed gel cyanoacrylates to the TS5622VU. It is necessary to install the TSD800-6FR regulator assembly for fluid pressure. Feed lines should be kept as short as possible so as not to restrict flow to the valve. Feed Tubing Feed tubing selection is important. ADL supplies polyethylene-lined tubing up to high pressures. Chemically inert to cyanoacrylate adhesives, our #TSD1099-23 (1/4� O.D. x 1/8 I.D.) polyethylene-lined tubing offers flexibility and performance. Input Fitting Selection Improper fittings lead to valve clogging and system failure. ADL recommends, and will only supply, polypropylene fittings for cyanoacrylate. Important: Do not use nylon or metal fittings. Nylon fittings absorb moisture, causing cyanoacrylate to cure. Metal fittings also react with the adhesive. Tip Adapter Use only ADL polypropylene tip adapters when dispensing cyanoacrylates. Do not use nylon or metal with CAs. Tags:
cyanoacrylate, superglue, crazy glue, instant glue, advice, overview, assistance, how to handle cyanoacrylate adhesive, Teflon tips, Teflon lined, TS1215, TS5622VU, TS500R,
|