Quench Tub Leak Repair

Not long after Thanksgiving I opened the studio one morning and was greeted with a flooded floor in the forge room.  It didn’t take long to notice that the quench tub was nearly empty.  The tank is 20” in diameter and 31.5” deep so there was a lot of water loose.

As a digression, I went to Google and did a couple of quick calculations with their handy dandy conversion tools.  First, I figured the volume of the cylindrical tank if full and then converted the cubic inches to gallons.

Calculation of cubic inch volume.

Conversion of cubic inches to gallons.

I had a big pile of old newspapers collected to use as coal fire starter so I scattered those all over the wet area to act as a makeshift sponge.  In a few days all the water was contained and I put the soaked newspapers outside to dry.  I shuffled them off and on until they were dry and I could store them again for their intended use.  

I was in the assembly mode and not the forging mode at that time so I waited until one of my sons came from California to spend Christmas to tackle moving the tub to a position where I could inspect and repair the leak. The drain spigot near the bottom had rusted and failed.  

I cut it away and brushed rust debris from the tank and fabricated a new plug which could be hammered in snug and then wired in place from the outside.  The hole area was sealed with Permatex thread sealant. http://www.permatex.com/products-2/product-categories/thread-compounds/thread-sealants/permatex--pipe-joint-compound-detail

New plug with safety wire.

When it dried I sprayed the inside with Rustoleum Leak Seal.  http://www.rustoleum.com/product-catalog/consumer-brands/stops-rust/leakseal

Since I wasn’t in any hurry I waited about three weeks to fill the tub  to a few inches above the spigot and wait to see what happened.  After another week without any sign of leak I filled it to near the top - the normal level.  A week has passed and the floor is dry.

Full of water and back in business.

Quench Tub Sieve

My main quench tub is a steel tank of about 40-gallon capacity which I hauled home from the scrap yard. I rarely actually quench anything as in the sense of rapidly cooling steel through the eutectoid point to harden it. I mostly use the water to cool steel that is still a bit too hot to pick up bare handed.

Too often a tong-held work piece would slip free and settle to the murky bottom where I’d have to retrieve it with a shoulder-depth plunge and finger search. I finally tired of that so I equipped all my quench tubs with handled sieves which can be easily lifted. The big one is in the forge room and there are three other smaller ones at other work stations.

In each case I used a ring roller to make a ring of strip stock such as 1/8” x 1” that loosely fitted the inside diameter of each quench tub. I then welded on a piece of expanded metal and cut around the outside of the band with the torch to remove the excess. A cross bar was welded for added strength and to provide a place to attach a vertical handle near the center.

I once stuck a sharp pointed bar into one of the tubs and poked a hole in the bottom which caused a leak and required repair. At the time I thought about cutting pieces of stall mat or some similar tough material to line the bottoms to protect them but so far haven’t gotten around to doing that.

http://www.persimmonforge.com/