Air lines that are damaged with cracked, chaffed or kinked jacketing, or that have corroded, or leaky fittings should be replaced to avoid air line failure on the road, Phillips says.

When replacing air lines, it’s important to select proper replacements that are not only quality, but also meet DOT standards, to ensure safety and avoid downtime while on the road.

Phillips suggests following these tips when selecting your next set of air assemblies:

• Select air assemblies that display appropriate markings that signify compliance with DOT regulations (required by law). Air lines are clearly marked DOT on the fittings and hose jacketing. If not, they are not approved as legal or safe for use as air brake lines.
• Select air coils made from nylon 11 and 12 (PA11 & PA12) which far surpass those made from polyurethane and nylon 6/6 in strength, durability, flexibility and memory recoil.
• Select air lines with Type B (dual wall) jacket layering, which has internal braiding. The smaller and tighter the braid, the more reinforcement there is throughout the walls of the air coil. Avoid Type A single wall jacketing with no internal jacketing.
• Select air lines with three or four-piece tractor side fittings. Unlike one-piece fittings, these types of fittings avoid spinning /corkscrewing the entire cable during installation.
• Select air lines with spring guards to protect the hose and tubing from sharp bends at or near the fitting.
• Select air lines that extend to their maximum expected service length and return to their retracted position without sag.
• When deciding between coiled or rubber, take into consideration the added weight of rubber air lines, which will require a stronger suspension system.

This Tech Tip was contributed by Phillips Industries.