Galvanized Steel Vs Stainless Steel Wire Rope
Wire rope is available in both stainless steel and galvanized steel compositions.
Stainless steel wire rope and galvanised steel wire rope are used for various industrial applications including rigging, lifting, utilities, marine and infrastructure projects, and it can be used in and around commercial and domestic properties.
This wire rope guide will help you make an informed decision before you buy either stainless steel wire rope or galvanised steel wire rope.
Although simple in its appearance, wire rope is a complex mechanical device that makes lifting, moving or supporting a load simple. Wire ropes are available in various compositions to suit different purposes. For example, wire rope can be rigid, flexible, restrict rotation and have features that limit corrosion, abrasion and crushing. In particular, it is common for wire rope to be fabricated from stainless steel or galvanised steel.
Galvanized Steel Vs Stainless Steel
What is Stainless Steel Wire Rope?
Stainless steel wire rope is very common and used in many commercial and industrial applications. Stainless steel has chromium added to the steel to provide some degree of protection against rust and corrosion. Stainless steel is not immune to those environmental effects but is better protected than pure non-treated steel. Stainless steel wire rope is used predominantly in applications where it is not exposed to the outdoor elements to avoid rust or corrosion damaging the wire rope.
Stainless steel wire rope is available in grades 304 and 316. 304 grade stainless steel is standard whereas 316 grade stainless steel is ideal for use in and around marine locations. 304 grade stainless steel contains approximately 18% chromium and 8% nickel while 316 grade stainless steel contains 16% chromium, 10% nickel and 2% molybdenum. The molybdenum is added to help resist corrosion to chlorides (like sea water, chlorides and de-icing salts).
What is Galvanized Wire Rope?
Galvanised wire rope is steel wire rope coated in a layer of zinc. The coating helps protect the steel from moisture in the air to prevent the wire rope from being susceptible to rust. This type of wire rope is ideal for use in marine locations where the wire rope is exposed to wet, damp and humid conditions. Galvanised wire rope helps to prevent the inner steel degrading from rust deposits.
While galvanised wire rope provides this benefit, it is not ideal for use in certain circumstances. These circumstances include: applications in and around salty sea water, use where corrosive chemicals are being handled, when food or medical products are being handled, applications where aesthetics are important and a shine is required, and others. In these circumstances it is preferable to use stainless steel wire rope.
Difference Between Galvanized Steel & Stainless Steel Wire Rope
The main difference between stainless steel and galvanised steel wire rope is the tensile strength. Given stainless steel is steel combined with chromium when the steel is in liquid molten state, this provides additional strength compared to galvanised wire rope composed of steel and a coating of zinc. Stainless steel wire rope is favoured by many for this very reason and during the wire rope’s service life, if maintained well, it performs highly effectively in various applications.
In addition to strength, here are a few other differences:
- stainless steel wire rope tends to be slightly more expensive than galvanised wire rope;
- galvanised wire rope is comparatively lighter in weight;
- since galvanised steel has a coating only, if the coating is damaged, the insider steel wire will be exposed to the elements; and
- stainless steel wire rope is used in applications where it will be exposed to oils and gasses.
Galvanized Wire Rope Specifications
Galvanised wire rope is steel wire hot dipped in zinc or electro-galvanised to protect the steel from rust and corrosion. This treatment provides a coating only and protection to the internal steel wire will no longer exist if the coating is breached. We stock galvanised wire rope available in fibre core or steel core, in 6x7, 6x19, 6x24, 6x25, 6x36, 7x7, 7x19 constructions.
Each type of wire rope construction is suited for different purposes and it is important that you check your standards, regulatory requirements and industry codes to ensure the correct wire rope is used. A wire rope with a thicker diameter will be more abrasion and crush resistant, whereas a thinner diameter will provide flexibility, bendability and not suffer fatigue.
Fibre core wire ropes are used where flexibility in handling, moving or supporting a load is required. Fibre core wire ropes are not suited for applications where there is prolonged outdoor exposure or crushing against other objects. On the other hand, steel core wire ropes have a higher tensile strength and are better suited to applications where there will be abrasions and crushing.
Stainless Steel Wire Rope Specifications
We stock stainless steel wire rope available in grades 304 and 316 in 1x19, 7x7 and 7x19 constructions. Each type of wire rope construction is suited for different purposes and it is important that you check your standards, regulatory requirements and industry codes to ensure the correct wire rope is used.
Here is an overview of the stainless steel wire ropes we stock:
- 1 x 19 construction: this type of wire rope consists of a single strand with 19 wires. Given the number of wires formed into the rope, it offers a high breaking load and is the least flexible wire rope construction. It will not bend around corners or angles and is ideal for straight line applications to support objects.
- 7 x 7 construction: this type of wire rope consists of 7 strands of 7 wires. It is not as flexible as the wire rope with a 7 x 19 construction but still has bendability characteristics.
- 7 x 19 construction: this type of wire rope consists of 7 strands with 19 wires each. This combination offers the greatest flexibility and is the most common and versatile in industrial and commercial applications. The wire rope is ideal for applications where there are bends and turns in the system. This type of rope also has some stretch in it.
Benefits of Galvanized Wire Rope
The benefits of galvanised wire rope are:
- cheaper than stainless steel wire rope;
- coated in zinc for enhanced protection against rust and corrosion;
- lighter weight than stainless steel;
- can be used in various applications as an alternative to stainless steel; and
- wire ropes are available in steel core or fibre core.
Benefits of Stainless-Steel Wire Rope
The benefits of stainless steel wire rope are:
- stronger than its galvanised counterpart – has a higher tensile strength;
- limited protection from rust – due to the addition of chromium;
- withstands higher pressures – ideal for freezing and high-altitude temperatures;
- impervious to fire and heat – suited for reasonably high temperatures;
- flexible – depending on the diameter of the rope, it offers flexibility and bendability; and
- longevity – owing to its strength it offers protection against abrasion and crushing.
At Keble’s Trading, we are a wire rope supplier that has been in business for 33 years. Supplying Melbourne with high-quality wire rope that has been selected to meet the needs of our customers, we understand what matters most.
If you are interested in a long-term relationship with us, you can open an account with us, and we will assign an account manager to give you a single-person contact for all your needs. Enquire today by calling 1800 067 687 or visiting one of our four showrooms today.