Repairs – Riggs Machine and Fabricating, Inc.

Precision Shafts to Get You Running Again!

05/30/201912/17/2021RMF

They say “wheels make the world go round”, but without shafts, nothing would ever move.

A shaft connects a mechanical power source to gears, wheels, turbines, rotors and much more. Shafts can be as simple a basic round bar or as complex as containing exacting bearing fits, keyways, sleeves, grease fittings, snap ring grooves and splines.

Often, the shafts we see have been in service for many years, sometimes running non-stop. Unfortunately when these older shafts break (as shown here), there aren’t drawings available and not a lot of time to get the new shaft machined and the unit running again.

This shaft broke and we got it in 2 sections, still in the housing. After disassembly, we made hand sketches. While the housing was cleaned and checked, we created 3D drawings and then machined a new shaft.

Here is the new shaft ready for inspection. After passing final inspection, the housing was reassembled and the unit was ready for production use.

Finished Shaft – Ready for Unit Assembly

Hopefully a broken shaft won’t take one of your machines, or worse, your facility down. But if it does, Riggs Machine has the experience to get you running again.

Riggs Machine & Fabricating – Serving industry in KY, OH and WV for over 45 years!

Shims – more than just a strip of metal

04/12/201904/17/2019RMF

SHIM – A washer or thin strip of metal used to align parts, make them fit or reduce wear.

These, sometimes extremely slender, strips of metal are very crucial in industrial operations. From getting a pump to line up perfectly or to make a surface level, a shim must be exact.

Shims come in a variety of materials, but most commonly from metals such as carbon steel, brass and stainless steel. And they also vary greatly in their thickness from up to 1/4” thick and down to .001 thick (imagine an industrial foil).

.003 thick shims – for precise applications

And the tolerances they must hold are key to their functionality. They cannot deviate across the surface, their dimensions must be held.

Often industrial shims come in sets of varying thicknesses. They can be added individually to get the final adjustments perfect.

They also come in many different shapes, often having to be custom designed to fit around existing bolt holes and other features. We like to add the small hand holds (show below) to make installation and adjustment easier.

At Riggs Machine and Fabricating we understand Industrial Shims and their importance in setup, maintenance and repairs. We understand the tolerances and design elements that separate a shim from a strip of metal. Yes, there is a difference. If the shop you are working with now doesn’t agree with that, then you are working with the wrong place. Time to call Riggs Machine.

Riggs Machine & Fabricating – Serving industry in KY, OH and WV for over 45 years!

Tapered Tube Plugs – Not as Simple as it Seems

11/20/201804/17/2019RMF

Used during repairs and outages, this simple looking device becomes a necessity. The Tube Plug is hammered or welded into the open section of pipes in boilers and heat exchangers. They plug the end of the pipe to either stop the flow of steam or coolant. If the plug’s seal is not tight the coolant can seep into the material and contaminate it.

What makes this seemingly basic item so important are a few factors. First, its fit must be right. Sure they are tapered, but they must fit without damaging the existing pipe or sliding too far in. Also, the material specifications for Tube Plugs can vary greatly. While some plugs can be made out a carbon steel like 1018, other plugs must match the existing pipe section (i.e. A350 with more carbon content) or even stainless steel, nickle or other metals. If the wrong type of metal is used, it could lead to corrosion, rust, leaks or a possible reaction with existing materials in the system.

Even the machining isn’t always as simple as it may seem. Bar stock in not always available in a size close to what the job requires or the material type needed is only available as plate. In that case, a plug larger than the finished size would be cut from the plate and then turned turn by hand on a lathe. Time consuming, yes, but necessary for a professional fit.

At Riggs Machine & Fabricating, we not only have the experience, but we ask the questions to make sure the job is done right, the first time. Don’t trust those supposed simple jobs to just any shop. Call Riggs first for the dependability and quality your facility demands.

*(Morton, John, 2 Electrolyte Heat Exchanger Tube Bundles in the 8×6 Foot Wind Tunnel, 1975) – http://catalog.archives.gov

Riggs Machine & Fabricating – Serving industry in KY, OH and WV for over 45 years!

Grapple – A Hook or Claw to Catch or Hold

08/28/2018RMF

And boy do they!

You may be familiar with the design, it has been used for years from junk yards to the toy dispenser in the mall arcade. The reason is simple, they work. The four finger design can lift almost anything. This is very handy in a scrap yard when you never know what is coming in next or the condition an item may be in.

This set is from a metal yard and they are abused on a daily basis. They pull scrap from rail cars and trucks all day and drop it into awaiting shredders and barges.

To extend the life of the hooks, the ends are cut off and new tips are welded on. All four “fingers” are replaced at the same time to keep balance and even wear of the unit. The key is making sure all four tips line up and meet in the center of the unit, ensuring maximum performance. Not an easy task on such a large and unwieldy assembly.

Here they are, ready for assembly on the unit. Soon they will be helping in the cycle of converting scrap into metal that will go back to the steel mills to make new products.