Lifecycle costing means adding up everything a part will cost you over the years you use it, not only what you pay for it today.

In corrosive environments, such as near the sea, around road salt or in chemical plants, that bigger picture often changes which part makes sense to buy. 

A cheap part that rusts quickly has to be replaced again and again. Each replacement means paying for new parts, paying someone to fit them and losing time while the equipment is out of action.

Over the years, those costs can add up to far more than the price of a better part that lasts.

What is lifecycle costing for components?

Lifecycle cost analysis adds up the costs of buying, owning, operating and disposing of an item. It lets you compare options that do the same job but differ in what they cost up front and later. Future costs are discounted back to today’s dollars, so a repair in year 12 doesn’t count the same as money spent today.

For a single part, that means the price you pay, the cost of fitting it, any cleaning or touch-up work, and the cost of replacing it when it wears out. If the equipment has to stop while that happens, the lost time counts too.

Picture a metal panel fixed to equipment that sits outside near the coast. Using stainless steel rivets to hold it on costs a little more at first. But the rivets have no outer coating that can wear off and let rust in. That means the panel can stay in place for years without someone having to come back and swap out rusty rivets.

Why does a corrosive environment change the math?

In mild conditions, a coated steel part may outlast the machine it’s fitted to. Near the sea, around road salt or in a chemical plant, the same part may need replacing several times.

The U.S. Department of Defense saw this with fencing at its sites. DoD research showed that bare zinc-coated steel has lower first costs but much higher life-cycle costs in corrosive environments. Standard fence and railing materials in those locations last only 5 to 7 years before they need replacing.

Corrosion cost the world about US$2.5 trillion in 2013, or 3.4% of global GDP. Using the corrosion control methods we already have could cut that bill by 15% to 35%.

How do you run a lifecycle cost comparison?

Start with how long you need the part to last, then price each option across that whole period.

1. 1. Decide on the time frame. For outdoor equipment, this is usually the expected life of the machine or structure, such as 20 years.
   2. Note what the part will face: salt spray, road salt, chemicals, damp air or standing water.
   3. Estimate how long each option will last in those conditions, using supplier data or your own maintenance records.
   4. Count every replacement in that time frame, including parts, labor, any lifts or scaffolding, and the time the equipment sits idle.
   5. Convert future costs to today’s dollars with your company’s discount rate.

The table below is an illustration, not a real quote. It compares 400 rivets on outdoor equipment near the coast over 20 years. It assumes plated steel rivets need replacing every six years, each replacement costs $1,500 in labor and downtime, and the discount rate is 3%.

Cost item	Zinc-plated steel rivets	Stainless steel rivets
Purchase price	$40	$150
Replacement in year 6 (today’s dollars)	$1,256	$0
Replacement in year 12 (today’s dollars)	$1,052	$0
Replacement in year 18 (today’s dollars)	$881	$0
20-year lifecycle cost	$3,229	$150

Over 20 years, the plated rivets end up costing more than 20 times as much as the stainless ones. Swap in your own prices and labor rates. The bigger the replacement bill compared with the part price, the bigger the gap.

Which component choices change most?

Coated steel versus stainless steel. Zinc plating can get scratched or chipped while parts are being installed. Once that happens, the steel underneath starts to rust. With stainless steel, service life depends on choosing the right grade for the conditions.

One stainless grade versus another. Not all stainless steel handles salt equally well. Type 316 stainless steel contains molybdenum, which helps it resist salt far better than Type 304. That makes it worth considering for parts near the coast or anywhere road salt is used in winter.

Matching the fastener to the metal it joins. When two different metals touch and get wet, one of them can rust faster than it would on its own. This is called galvanic corrosion, and which metal is the fastener matters. Stainless steel rivets in aluminum sheet are normally safe, but aluminum rivets holding stainless steel parts together are a poor match.

When does the cheaper component still make sense?

The lower-cost option often wins when:

• The part sits indoors in a dry, heated space.
• The equipment will be scrapped or replaced before the coating fails.
• The part is easy to reach and quick to swap during planned maintenance.
• A failure would cause no safety risk and no unplanned downtime.

What should procurement teams ask suppliers?

Before you sign off on a corrosion-resistant part, get these four things from the supplier in writing:

• The exact grade and finish, such as 316 rather than just “stainless.”
• Material certificates that trace the part back to the mill that made the metal.
• Service life data for conditions like yours.
• Advice on which metals the part can safely touch.

Material traceability protects the finished asset because it confirms you received what you specified. A 304 part supplied in place of 316 looks the same on the shelf, so the paperwork is often the only way to spot the swap.

It also helps to buy these parts the way you would treat industrial screens as a long-term purchase, planning for availability and service life rather than the lowest price. That matters most when a replacement means shutting down a line or sending a crew to a remote site.

Pricing parts for the long run

The next time two quotes land on your desk for the same part, ask each supplier how long it will last where you plan to use it. That answer often matters more than the price.