For a lot of plants, the year-end shutdown is the one stretch of the year when a process tank can come out of service without stopping production. That makes it the natural time to inspect a rubber lining and, if it’s worn, to reline it.
The catch is timing. Moon’s typical lead time for a reline is 4 to 6 weeks, to inspect the tank, specify the lining, order materials and schedule a crew before the window opens. If your plant shuts down at the end of December, the planning starts now. Here’s how to work backward from your shutdown date so the tank is back in service, lined and cured, when production restarts.
Signs a tank lining is due for inspection or reline
Rubber linings protect tanks for years, but they don’t last forever. Heat, abrasion, chemical exposure and cleaning all wear on them. These are the common signals that a lining needs a closer look:
• Blisters or bulges in the rubber, which can mean the lining is losing its bond to the steel
• Cracks, cuts or worn spots, especially where slurry or solids hit the wall
• Edges or seams lifting around nozzles, manways and corners
• Rust staining or leaks on the outside of the tank
• Product contamination, since corroding metal can get into what the tank holds
• A change in service, such as a new chemical or a higher operating temperature than the lining was specified for
Moon recommends regular inspections to catch these problems early. A small repair found during a planned inspection is far cheaper than an unplanned outage. If the tank stores oil or petroleum products, federal and state rules may also require routine inspection; see our overview of tank inspection regulations.
Shop reline or field reline: it comes down to size
The first planning decision is where the work happens, and the tank’s size usually makes it. Tanks and parts that can be removed are relined and cured in Moon’s Kokomo shop. Large-diameter storage tanks, 16 feet across or larger, are lined in place by Moon’s field crew.
| Shop reline | Field reline | |
| Which tanks | Tanks and parts that can be removed and shipped | Large-diameter storage tanks, 16 ft across or larger |
| Where | Moon’s shop in Kokomo, Indiana | Lined in place at your plant |
| How it cures | Pressurized steam in Moon’s vulcanizer | Atmospheric cure: steam injected into the tank itself |
| Cure temperature | 275°F or higher | About 200°F |
| Cure time | Generally under 3 hours | About 36 hours |
| Bond strength | Highest adhesive bond | Lower than vulcanized; still meets the manufacturer’s prescribed properties |
| Plan around | Removal, freight both ways, reinstallation | Site access, confined-space entry, and 36 hours of cure time in the shutdown schedule |
Why the two cures are different
Steam can’t get hotter than 212°F, its boiling point, unless it’s under pressure. Moon’s vulcanizers are pressure vessels: a 12-foot by 40-foot unit for large components and a 2.5-foot by 30-foot unit for smaller parts. Under pressure, a shop cure reaches 275°F or higher and is generally done in under three hours. For more on that process, see rubber vulcanization for tank and pipe liners.
A 16-foot storage tank won’t fit in a vulcanizer, so the field crew makes the tank its own steam containment. Steam is injected into the tank and held at about 200°F for roughly 36 hours. This is called atmospheric curing: a lower temperature, held much longer.
Atmospheric-cured linings have a lower adhesive bond strength than vulcanized linings, but both methods produce a lining with the mechanical properties the rubber manufacturer prescribes. Moon’s field service crews handle the sandblasting, lining installation and cure on site.
How to plan a reline around your shutdown
Start from the date production restarts and work backward, giving yourself at least six weeks. These steps, in order, keep a reline from running past the window:
- Inspect the lining six or more weeks out. Use the last scheduled inspection, or bring in a crew, to decide whether the tank needs a spot repair or a full reline.
- Gather what you know about the service. Chemicals, concentrations, operating temperature, abrasion and cleaning methods all drive which lining system will hold up.
- Choose the lining and the location. Rubber, abrasion-resistant, fiberglass (FRP) or a specialty coating. Removable tanks go to the shop; storage tanks 16 feet across or larger are lined in place.
- Lock in the schedule and materials. Moon’s typical lead time is 4 to 6 weeks, so book the crew and order materials early enough that nothing waits once the tank is drained.
- Prepare the site. Drain and clean the tank, and plan access, permits and confined-space entry before the crew arrives.
- Reline, cure and test. Surface prep, lining application, then the cure: generally under three hours in the vulcanizer, or about 36 hours for an atmospheric cure in the field. Build that cure time into the shutdown schedule, followed by inspection and testing.
- Return the tank to service and record the lining type, cure method and date, so the next inspection starts with a baseline.
How Moon handles relines
Moon has been fabricating and lining tanks in Kokomo, Indiana since 1923, and serves plants across the United States. That means the team relining your tank also builds new ones, and knows how the steel underneath was meant to perform.
• One team from inspection to return to service. Moon’s field service crews handle inspection, sandblasting, repairs and on-site rubber lining installation, with a project manager guiding the job.
• The right cure for the tank. Removable tanks and parts are vulcanized under pressure in Moon’s Kokomo shop for the strongest bond. Large storage tanks are lined in place and atmospheric-cured on site.
• Linings matched to the service. Moon applies rubber, abrasion-resistant, Hypalon, chlorobutyl, Koroseal and PVC, vinyl ester, and fiberglass (FRP) linings, and is an approved applicator for Blair Rubber Co. and Polycorp Ltd.
• Built to standard. Moon’s rubber linings meet ASTM D7602, the standard for installing rubber lining sheet stock in metal tanks and pipes, and each job is tested and inspected before the tank goes back into service.
If a tank bottom has small perforations, an FRP lining can bridge them and extend tank life by 10 to 20 years, which can make a reline a better option than replacing the tank. Not sure rubber is the right choice? See Is rubber lining the right solution for you?
Frequently asked questions
During a planned shutdown, when the tank can come out of service without stopping production. With a typical 4- to 6-week lead time, start planning at least six weeks before the shutdown begins.
Look for blisters, cracks, worn spots, lifting edges or seams, rust staining or leaks on the outside of the tank, and product contamination. A change in chemicals or operating temperature is also a reason to recheck the lining.
Yes. Large-diameter storage tanks, 16 feet across or larger, are lined in place by Moon Fabricating’s field crew and cured on site with steam injected into the tank.
A shop reline is for tanks and parts that can be removed. They’re cured in Moon’s pressurized steam vulcanizer at 275°F or higher, generally in under three hours. A field reline is for storage tanks 16 feet across or larger, which are lined in place and atmospheric-cured at about 200°F for roughly 36 hours.
Atmospheric curing cures a rubber lining in place by injecting steam into the tank, so the tank serves as its own steam containment. Without pressure, steam can’t exceed 212°F, so the lining is held at about 200°F for roughly 36 hours instead of a few hours in a vulcanizer.
Vulcanized linings have a higher adhesive bond strength, because the pressurized cure runs hotter. Atmospheric-cured linings bond less strongly but still meet the mechanical properties the rubber manufacturer prescribes.
Moon’s typical lead time for a reline is 4 to 6 weeks. Once work starts, the cure itself is generally under three hours in the vulcanizer, or about 36 hours for an atmospheric cure in the field.
Rubber, abrasion-resistant rubber, Hypalon, chlorobutyl, Koroseal and PVC, vinyl ester, fiberglass (FRP) and specialty coatings. Moon is an approved applicator for Blair Rubber Co. and Polycorp Ltd.
Often, when the steel shell is still sound. An FRP lining can bridge small perforations in a tank bottom and extend tank life by 10 to 20 years.
Get your reline on the shutdown schedule
With a 4- to 6-week lead time, a reline for a year-end shutdown needs to be on the calendar now. If a tank is due for inspection or showing signs of wear, Moon’s team can help you decide between a repair and a full reline, pick the right lining and cure, and schedule the work.
Request a quote or call (765) 459-4194 to talk with our team.