Fertilizer

Waste Heat Boilers

Background

A company had a vessel that leaked constantly during start-up, while running and during shut-down.

The client attempted to remedy the problem with either a hydraulic wrench or clicker wrenches, which was costly since they could never find an accurate setting and the dismantling and resetting was time consuming.

Problem Being Addressed

The vessel always leaked.

Approach Taken

We suggested they perform a flange study and use eight hydraulic tools at one time.

The flange study told us gasket type, desired torque and the type of lubrication needed.

End Result

We were correct in our assessment: using eight hydraulic tools, we were able to bring the flange down evenly and seal the gasket without pinching or ruining it.

After start-up, when there were no leaks, we reverted to hot torque and saw no movement on the nuts.

Stud and Nut Cleaners

Background

Alltite was called out to break loose, clean, re-lubricate and reinstall 20 5-inch acorn nuts on a secondary urea reactor. This case study highlights the methods used for cleaning the studs and nuts.

These nuts were a custom product with three parts and then the 5” studs.

In the past, they client had cleaned the parts by hand, assigning approximately five employees to the task of using electric wire wheels to clean off the caustics like rust and old bolt lube, which took approximately three days.

The process consisted of cleaning the outer nut sleeves, washers, and the threads on the inner sleeve of the nuts along with the OD of the studs. The wire wheels caused localized pitting of the material on the threads, which acted as premature galling of the nuts and studs.

Alltite’s suggested approach provided a more even, clean and non-destructive method that proved to be 10 times faster with fewer than half the people.

Approach Taken

Alltite came on-site with our bolt cleaning system including inner and outer portable cleaning sockets made to exactly fit the thread diameter and  run on a standard electric drill. We also brought a stand-up machine with three wire wheels rotating in different directions to clean a stud in 20 seconds and spin for re-lubrication with anti-sieze.

This system was rented to the customer and was cost-justified on the first use by reduction of man hours alone. The cleaning system did a much more thorough, uniform job cleaning the hardware, minimizing the possibility of galling and reducing the coefficient of friction between the thread-bearing surfaces.

End Result

The new cleaning system only took two men a total of 20 hours. The 80-lb nuts were steam-cleaned, which was such a leap forward from former methods that the customer volunteered to be a reference for anyone interested in this bolt cleaning method.