Flamemaster CS-143 Class B - Non-Chromate Corrosion Inhibitive Sealant (AMS-3265)

CS 143 Class B is a two-part, manganese dioxide cured polysulfide sealant specifically designed as a non-chromate corrosion inhibitive sealant for aerospace applications. It offers the traditional excellent fuel and fluid resistance of polysulfide sealants but incorporates environmentally friendly corrosion inhibitors that do not contain hexavalent chromium. The "Class B" designation indicates its trowelable consistency, making it suitable for application by spatula or extrusion gun for sealing seams, fasteners, and small access panels. Upon curing at room temperature, CS 143 Class B forms a tough, flexible, and resilient rubber that provides long-lasting protection against corrosion and leaks, even in harsh aviation environments, while addressing environmental and health concerns associated with chromates.

Key Characteristics:

• Two-Part System: Consists of a base compound and an accelerator, mixed immediately prior to application.
  
• Polysulfide Chemistry: Provides excellent resistance to a wide range of aviation fuels, hydraulic fluids, and lubricants.
  
• Non-Chromate Corrosion Inhibition: This is its defining feature. It contains advanced corrosion inhibitors that offer effective protection without the use of hexavalent chromium, making it a safer and more environmentally compliant choice.
  
• Manganese Dioxide Cure: A common curing agent for polysulfide sealants, contributing to robust and durable properties.
  
• Class B Consistency: Trowelable, making it easy to apply with a spatula, spreader, or extrusion gun for creating fillets and sealing larger areas.
  
• Excellent Adhesion: Forms strong, durable bonds to typical aircraft substrates, including aluminum, titanium, stainless steel, and composite materials, even on clad aluminum.
  
• Superior Fuel and Fluid Resistance: Highly resistant to aviation jet fuels (JP-4, JP-5, JP-8, Jet A/B), hydraulic fluids (e.g., Skydrol), and engine oils.
  
• Wide Service Temperature Range: Maintains flexibility, sealing properties, and corrosion inhibition across the typical operating temperatures of aircraft.
  
• Flexibility and Resilience: Cures to a flexible, rubbery seal that can withstand aircraft vibrations, thermal cycling, and structural movement without cracking or delamination.
  
• Good Work Life (Pot Life): Provides sufficient time for application before curing, depending on the specific "B" class variant (e.g., B-1/2, B-2, B-4, where the number indicates the pot life in hours).

Application in Aviation:

• Sealing Integral Fuel Tanks: Provides a leak-proof and corrosion-inhibiting seal for fuel tanks, especially relevant in new aircraft designs or major repairs moving away from chromated products.
  
• Sealing Structural Airframe Joints: Used in various structural joints, seams, and fasteners throughout the aircraft to prevent corrosion from moisture ingress or dissimilar metal contact.
  
• Corrosion-Prone Areas: Applied in areas known to be susceptible to corrosion, such as bilge areas, landing gear bays, and other compartments exposed to environmental elements.
  
• Fastener Sealing: Ensures effective sealing and corrosion protection around rivets, bolts, and other fasteners on fuel-wetted or exposed surfaces.
  
• Access Panel Sealing: Used to seal removable access panels on fuel tanks or other compartments requiring both sealing and corrosion inhibition.
  
• Repair Applications: An excellent choice for both production and field repairs, offering a safer alternative to chromated sealants while maintaining high performance.
  

• All in-stock orders are processed within 1–2 business days (excluding weekends and holidays) after receiving your order confirmation email.
• Orders with a lead time will ship according to the estimated shipping time shown on the product page.
• If we experience a high volume of orders or if an item is backordered, processing times may be slightly delayed. We will notify you promptly via email.

• Returns must be made within a maximum of 3 business days after receiving the product, with prior authorization from Aircraft Shop Supply (Return Material Authorization). Returns without prior notice or written authorization will not be accepted.
• For products with 3 to 6 months of remaining shelf life, claims must be made within the next 2 business days after receipt.
• Returns are not accepted for products with less than 3 months of remaining shelf life.
• Returns are not accepted for products purchased during a low Shelf Life promotion, items sold with discounts, or special orders that must be placed directly with the factory.
• The customer is responsible for the return shipping cost, except in cases where the return is due to an error on the part of Aircraft Shop Supply.
• Refunds will only be issued after the product has been inspected and no damage is found.
• A 25% Restocking Fee will be charged for returns of products in good condition that are either no longer needed or were ordered incorrectly.
• A 35% Restocking Fee will be charged for returns of products with one year or less of remaining shelf life.
• No Restocking Fee will be charged if Aircraft Shop Supply is responsible for incorrectly shipping a product, or if the order is damaged upon leaving the warehouse.
• Hazardous Materials & Dangerous Goods: These items are sold as final and are not eligible for return approval.