PPG Aerospace® P/S 870 Class B-1/2 Corrosion Inhibitive Sealant

Create a durable seal in seconds using PPG Aerospace P/S 870 Class B Corrosion Inhibitive Sealant from SkyGeek. The low-sag formula is specifically designed for use on aircraft parts and is resistant to drips or streaks, making it a great choice for sealing vertical surfaces. This high-performance aerospace sealant has many different uses. Use it to seal fuel tanks, electrical work, aluminum alloys and more. It can also be used for priming and top coats or for bridging mixed metals. Apply the low-sag formula with a spatula or extrusion gun without running the risk of the sealant dripping or sagging, leaving behind a smooth, beautiful surface. Once the sealant is fuel aged or fresh cured, P/S 870 works to prevent leaks and to maintain a quality seal. It's slightly flexible after curing, offering better protection in all types of weather and conditions. It even works in extreme temperatures, holding strong without melting or pulling away. It also maintains excellent adhesion and easily withstands weathering and stress for a quality seal you can depend on.

PPG Aerospace P/S 870 Class B Corrosion Inhibitive Sealant is the perfect choice for use throughout your aircraft. The low-sag formula is easy to apply and dries quickly, preventing leaks and forming a tight bond. The adhesive sealant is available in a variety of container sizes and a manufacturer's certification may be added to any order for a small additional charge. Same day shipping is also available on select sizes.

Approvals, References and Specifications:

• MIL-PRF-81733D

Features:

• High-performance corrosion inhibitive sealant
• Can be used for fuel tanks, electrical work, priming and top coats, aluminum alloys and bridging mixed metals
• Remains flexible in extreme temperatures
• Withstands weathering and stress
• Can be fuel aged or fresh cured
• Retains adhesive properties in harsh conditions
• Low-sag formula can be applied with a spatula or extrusion gun
• Service temperature range: -65 degrees Fahrenheit to 180 degrees Fahrenheit
• Available as P/S 870 B-1/2 two-part kits or Semkit ® cartridges

PRC and Pro-Seal Aeroscape Sealants Application Guide

Introduction

PRC-DeSoto International PRC®, Pro-Seal®, Permapol® P-3 brand products are designed for interior/exterior aircraft sealing and coating applications. The traditional Polysulfide and the high performance Polythioether compounds are used for fuel tank sealing, corrosion inhibition, aerosmoothing, electrical insulation, windshield/canopy sealing, priming and topcoating.

Note: It is important to read and understand the MSDS, process specification, and technical data sheet before working with these products.

Surface preparation

Immediately before applying sealant to primed substrates, the surfaces should be cleaned with a solvent i.e., Desoclean® 110. Contaminants such as dirt, grease, and/or processing lubricants must be removed to insure good adhesion prior to sealant application.

A progressive cleaning procedure should be employed using the appropriate solvents and new lint free cloth (reclaimed solvents or tissue paper cannot be used). Always pour solvent on the cloth to avoid contaminating the solvent supply. Wash one small area at a time. It is important that the surface is dried with a second clean cloth prior to the solvent evaporating to prevent the redeposition of contaminants on the substrate. Substrate composition can vary greatly. This can affect sealant adhesion. It is recommended that adhesion characteristics to a specific substrate be determined prior to application of sealant on production parts or assemblies.

Special notes: For integral fuel tank repair where fresh sealant will be applied over aged fuel soaked sealant, the use of an adhesion promoter like PR-148 or PR-182 is essential.

If a Polythioether is to be applied over a polysulfide, either PR-186 or PR-1826 AP must be used at the sealant interface.

For a more thorough discussion of proper surface preparation, please consult the SAE Aerospace Information Report AIR 4069. This document is available through SAE, 400 Commonwealth Avenue, Warrendale, PA 15096-0001.

Packaging

PRC-DeSoto International Sealants are generally available in three different package configurations:

1. Two-Part Can Kit: Packaged with part A and part B pre-measured into separate containers.

2. Semkit® package: A complete package assembly that stores, mixes, and applies sealant. Semkit® packages eliminate the labor intensive task of measuring and handling materials, and prevent contamination when opening and closing cans kits.





3. Premixed and Frozen (PMF): Pre-measured mixed material and frozen at extreme low temperature. PMF material is the most convenient package configuration for high usage applications, simply thaw and use.

Mixing instructions

Proper mixing and correct component proportions are extremely important to assure optimal results.

Two-part can kits

1. Kits consist of the proper proportions of base compound (part B) and accelerator (part A). The entire contents of both containers are intended for mix at one time.

2. Before using material, read and understand the process specification and the Material Safety Data Sheet (MSDS), which provides information on health, physical and environmental hazards, handling precautions and first aid recommendations.

3. Carefully, remove the rim from Part B container.

4. Thoroughly stir Part A in the original container with a flat metal spatula until an even consistency is obtained.





5. Slowly stir the entire contents of Part A into the Part B container and thoroughly mix to uniformity for approximately 7 to 10 minutes.

6. Scrape the sides and bottom of the container to include all compound in the mixture and assure uniform blending. The mixing spatula should also be scraped clean periodically.

Note: Slow mixing by hand is recommended. A high speed mechanical mixer should not be used as internal heat will be generated reducing application life and introducing air in mixture.

Injection style Semkit® package

1. Before using material, read and understand the process specification and the Material Safety Data Sheet (MSDS), which provides information on health, physical and environmental hazards, handling precautions and first aid recommendations.

2. Hold cartridge, grasp dasher rod, and pull back approximately one inch.

3. Insert ram rod into hollow of dasher rod, break piston loose, and inject about one-third of the contents into the back third of the cartridge.





Note: Use even pressure; do not use force, tap, pound, or jolt ramrod if piston does not break loose readily.

4. Pull back dasher rod and inject one-third of the rod’s contents at the mid point, then pull back dasher rod and inject the last third one inch from the threaded end of the cartridge. Remove ramrod.

5. To mix, hold cartridge and push dasher rod to the plunger end. Begin stroking the dasher rod in a spiral clockwise motion from the end of the cartridge to the plunger. Rotate the dasher rod approximately 90 degrees each stroke. A stroke is one complete in and out cycle. Mix material for the required number of strokes for hand mix, or for the required time for machine mix, as indicated on the instructions provided with the Semkit®.

6. After mixing, remove bottom cap.

7. Pull dasher rod back to the neck of the cartridge. Grasp cartridge firmly at the neck, unscrew dasher rod and remove.

8. Screw nozzle into cartridge, insert into Semco® extrusion gun, and use as required. For hand extrusion, press used dasher rod against plunger to force material from cartridge.

Note: It may be desired to use a Semco® mixer model 388 for mixing sealants packaged in cartridges. Mixer does not reduce the number of strokes required for complete mixing, it does allow the material to be mixed easier and faster.

Storage instructions

Two-part kits and Semkit® package

Sealants should be stored according to the instructions on the container.

Premixed and frozen (PMF)

Polysulfide sealants in a PMF form should be stored in a freezer at –40°F (-40°C) or below for optimal retention of application properties and shelf life.

Polythioether sealants require extreme low temperature refrigeration at –80°F (-62°C), or below for optimal retention of application properties and shelf life.

Thawing of PMF can be accomplished in two ways:

Ambient Thaw: Place the PMF cartridge to be used on a bench in a vertical position. Let stand at 70-80°F (21-27°C) for approximately 30 minutes. Dry any condensation from the exterior of the cartridge prior to use.

Water Bath Thaw: Place the PMF cartridge upright in a 120°F (49°C) water bath for approximately 4-6 minutes. Upon removal from the bath, carefully dry the exterior of the cartridge before using.

Cure

Application life and cure times are dependent upon ambient environmental conditions. Increases in temperature will shorten application and cure time. Conversely, lower temperatures will increase application life and cure time.

Manganese dioxide cured polysulfides: relative humidity affects the cure rate. Low humidity increases tack free and cure times. High humidity accelerates or shortens the cure time for manganese dioxide cured polysulfides.

Cure may be hastened by applying heat. Polysulfide sealants with a two hour, or less, application time, can obtain a serviceable cure hardness of 30 Durometer A after eight hours at 125±5°F (52±3°C).

Although polysulfide sealants develop a high state of cure in 14 days at 75°F (25°C), longer cure times further improve ultimate resistance to fluids, heat, and pressure. Maximum cure is usually obtained in 30 to 50 days.

Cleaning of application equipment

Wash equipment with a non-chlorinated solvent immediately after use or before sealant cures. Use commercial stripping compounds to remove cured sealant.

Health and safety

Before using a product, read and understand the Material Safety Data Sheet (MSDS), which provides information on health, physical and environmental hazards, handling precautions and first aid recommendations. Avoid overexposure. Obtain medical care in case of extreme overexposure.