What Makes Fiberglass Rope Unique?

Rope is used everywhere from rock-climbing to sailing to clothing accessories to exercise equipment, and more. The history of rope making dates back to ancient Egypt (~20,000 years ago), but the use of rope extends back much further. The exact timeline of rope history is unknown, but what is known is how useful it has become in everyday life. One very specific type of rope used today is fiberglass rope.

Fiberglass rope is a flexible rope made from heat tolerant material which is typically used as a sealing solution in high temperature environments, but can also be used as compression packing for rotary equipment such as pumps and valves. What makes this type of rope so unique? Let’s explore this question by:

• comparing fiberglass rope to a similar product
• looking at its different variations
• identifying its significant properties

Fiberglass rope vs. Ceramic fiber rope

Fiberglass rope isn’t the only rope designed for high temperature use. Ceramic fiber rope, manufactured from alumino-silicate based ceramic fiber combined with fiberglass reinforcement, is another product used for packing and sealing in high temperature environments. The main differences between the two are their working temperature, strength, and price. While ceramic fiber rope can be used in higher temperature environments it is not as strong and is more expensive.

Fiberglass rope variations

Standard rope comes in various forms and windings. The same is true for fiberglass rope. Braid variations include round, square, multi-strand twisted, and knitted. These variations control density which is important depending on the application. If the application requires durability, a high density (square braid) is preferred. If installation in the application area is difficult due to an unusual geometry or sharp bends, then a lesser density (knitted) is needed. If an application requires a density somewhere between firm and medium, then a round braid (medium-high density) should be used.

Fiberglass rope properties

There are five notable properties of fiberglass rope:

1. Working temperature – The working temperature of a material is temperature at which a material will maintain it’s structural integrity. The working temperature of some common types of materials are listed in the article “Understanding the Properties of Flexible Graphite”. The working temperature of fiberglass rope is 1000 degrees F (538 degrees C).
2. pH – pH is a scale from 0 – 14 that is used to measure how acidic or basic an aqueous solution is. The middle of the scale (pH = 7) is considered neutral. Pure water has a pH of 7. The lower the pH, the more acidic it is. Similarly, a higher pH is more basic. Fiberglass rope can be used in applications where the aqueous solution has a pH range from 2 – 12.
3. Thermal conductivity – Thermal conductivity is a measure of a material’s ability to conduct heat. Fiberglass rope has low thermal conductivity, which is necessary in for materials that must be heat resistant. More details about thermal conductivity can also be found in “Understanding the Properties of Flexible Graphite”.
4. Tensile strength – Tensile strength is a material’s ability to resist breaking under tension. Fiberglass rope has high tensile strength and will resist stretching and shrinking. Tensile strength is also discussed in more detail in the “Flexible Graphite” article.
5. Dielectric strength – The dielectric strength of fiberglass rope is high, which means that it is a good insulator. Dielectric strength is a measure of a material’s electrical strength as an insulator, measured in volts per unit of thickness. The voltage at which a given material of given thickness starts to electrically break down is called the breakdown voltage. Dielectric strength and breakdown voltage have the following relationship:

Heat + Chemical + Electric + Strength

The five properties of fiberglass rope address four concerns:

1. heat
2. chemicals
3. electricity
4. strength

The working temperature and thermal conductivity properties of fiberglass rope allow it to be used in high temperature environments. The vast pH tolerance range of fiberglass rope makes it chemically resistant. The high dielectric strength of fiberglass rope makes it a great insulator. And the high tensile strength of fiberglass rope makes it resilient.

Uniqueness of Fiberglass Rope

Fiberglass rope is unique. It is used in very specific applications. Ceramic fiber rope can be used for some of the same applications but fiberglass may be a better choice, depending on the circumstances. If trying to decide between the two types, determine your heat management, budget, and durability requirements. Fiberglass rope may be the best option.