Sikaflex® - General Guidelines
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Industry General Guidelines Bonding and Sealing with Sikaflex®

General Guidelines for Bonding and Sealing with Sikaflex® Products Selecting Adhesives and Sealants Design and Dimensions of Adhesive Joints and Seals Working Place Conditions Surface Preparation Techniques 6.2 Surface Activators (e.g. Sika® Cleaner-205, Sika®Aktivator, etc.) Application of Adhesive and Assembly Tooling / Smoothing 12. Practical Testing Procedures to Evaluate the Quality of the Adhesion 12.2 Through Hardening Test for Booster Applied Products Legal Notes © August 2006 / Version 3 / Sika Services AG

General Guidelines for Bonding and Sealing with Sikaflex® Products Purpose and Scope These Guidelines contain information and recommendations for users on the correct use of Sikaflex® sealants and adhesives in industrial applications. They should be read in con­junction with the relevant Product Data Sheets, Pre-tratment Chart and Working Instructions. This document covers general recommendations, for specific recommendations please contact your local Sika company (www.sika.com). This document contains important Sika know-how. It is therefore primarily for internal use only and may handed...

General Guidelines for Bonding and Sealing with Sikaflex® Products Working Place Conditions The working place should be as dust free as possible. No work with silicones, paints or solvents should be performed in the surrounding area. For best practice the work area should be separated from the other areas and provided with corresponding signs. Ideal conditions are 23°C (73°F) and 50% relative humidity. As these conditions are usually attainable only in a laboratory, try to make plant conditions as close as practicable. Be aware that all values stated in the Product Data Sheets are based on...

General Guidelines for Bonding and Sealing with Sikaflex® Products Therefore, it is essential to assure that surface characteristics of all bonded components are constant and uniform in terms of chemical compo­sition, manufacturing processes, production aids such as mould release agents or preservatives such as waxes, oils, etc. Paint coatings must be carefully analyzed and identified. The chemical composition of the paint, type of substrate preparation, application parameters, and the presence of additives in the paint to modify texture or finish can affect final adhesion. Important note...

General Guidelines for Bonding and Sealing with Sikaflex® Products 6.3 Priming Sika Primers are clear or pigmented liquids that bond well to the substrate and dry to form an ideal surface for adhesion. Primers are generally applied with a clean, dry brush, a special felt-pad or a piece of open cell elastic polyurethane foam applicator. A broad selection of applicator systems are also available at www. designetics.com. In certain limited instances Sika® Primer can be applied by spray or with rollers. Always contact Sika Technical Service for advice in such cases. Each Sika® Primer has a...

General Guidelines for Bonding and Sealing with Sikaflex® Products Application of Adhesive and Assembly Sika adhesives and sealants supplied in cartridges and unipacks are applied with a pneumatic-, electric- or manually operated application gun. They may also be dispensed from drums and pails through a pump system. For more controlled dosage and limiting air entrapment, adhesives are best applied in the form of a triangular bead. Do not exceed the tack free (skin formation time) or open time published on the Product Data Sheet. Cold temperature and low humidity slows the tack free time...

General Guidelines for Bonding and Sealing with Sikaflex® Products Tooling / Smoothing Tooling is performed using the most suitable tool for the desired appearance, such as spatula, spoon or cut potato having a even edge. The operation may be optimised using an appropriate tooling liquid. We recommend Sika® Tooling agent N. Important note Tooling products such as solvents, concentrated detergents or other cleaners may cause tacky surfaces or accelerated aging of the smoothed surface. Never under any circumstances use alcohol or alcohol containing products as a tooling agent (it prevents the...

General Guidelines for Bonding and Sealing with Sikaflex® Products 11. Quality Assurance Quality assurance measures play a vital role in adhesive bonding technology. These include the following points: • Monitoring the substrate materials for consistency and assure information flow from purchasing department in case of changes of substrates or material suppliers. Laboratory analysis or empirical bonding tests may be necessary to verify it. • Detailed Working Instructions must be clearly displayed in the workplace. Instructions should be easy to read and preferably based on the use of...

General Guidelines for Bonding and Sealing with Sikaflex® Products 12. Practical Testing Procedures to Evaluate the Quality of the Adhesion 12.1 Adhesion Test Apply a triangular bead on an original substrate which has been prepared in accordance with the Primer Chart or Working Instructions (see pic. 1). Use release paper, wax paper or polypropylene foil to press bead down approximately half of the bead height (see pic. 2 and 3). Allow the bead to cure for 7 days at room temperature (23°C/50% relative humidity). Using a sharp razor knife, separate the first 3 cm of the leading edge of the...

General Guidelines for Bonding and Sealing with Sikaflex® Products 12.2 Through Hardening Test for Booster Applied Products A thick bead of about 3 cm diameter and 100 mm length is applied on cardboard. After 2 hours at 23°C/50% relative humidity, the bead is cut with a razor knife to determine if the entire bead has cured. If not fully cured, repeat every half hour until curing is complete. 13. Additional Information These General Guidelines must be read and interpreted in conjunction with Sika’s Product Data Sheets, Material Safety Data Sheets and instructions for use current at the time...