Welding – Riggs Machine and Fabricating, Inc.

Handwheel Extensions & Ease of Operation

06/14/2019RMF

When a valve handle is not readily accessible, or the distance for proper operation is too great, a Handwheel Extension might be the solution.

Once affixed to the existing valve, workers have quick, ready and safe access to the controls when need arises.

Shown above, an inaccessible gate valve is below a platform. With a bolt-on Handwheel Extension, a worker on top of the platform now has convenient, safe access within reach and can operate the valve freely (without the need of ladders or rigging).

Also, by increasing the diameter of the handle on the Handwheel Extension, the valve may be easier to operate than it may have been with its original smaller handle.

These Handwheel Extensions are custom designed based on the valve size and distance from the valve to the operator’s control location.

Handwheel Extensions are often galvanized to help withstand the weather, elements and possible corrosion from chemicals in the facility.

If you have inaccessible valves that require outside rigging to operate or controls that put your employees in dangerous situations, call Riggs for an overview of the benefits that Handwheel Extensions can offer.

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

A Fabrication Story – The Bearing Pedestal

03/20/201904/17/2019RMF

There’s a reason for the fabricating in Riggs Machine & Fabricating. Here’s a perfect example. A client has an older machinery pedestal in very poor condition and needs a new assembly. There are, of course, no design drawings for the item, but luckily we can bring it to our shop.

First we make hand sketches of the unit. We review the original design to see if there were any structural defects that should be improved or any new features that the client would like to have implemented in the current design.

Next, these sketches are converted to CAD drawings and then 3D models are created for fit-up and testing. It’s much faster (and cheaper) to test a new design in 3D than it is after cutting 1/2” thick plates. When we are satisfied with the design, the files are sent out to have plates cut.

This is what we get back from the waterjet cutters (Swift Manufacturing), nice pallet of loose parts. Now fabrication begins. If the designers did their work properly, the welders job should go smoothly.

And here we have the final assembly. From hand sketches to CAD to 3D models to cut parts to fabrication in less time than it takes some companies to return your call.

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

Industrial Platform Handrail – Ergonomics and Safety

10/31/201804/17/2019RMF

Industrial platforms and walkways typically use one of two types of handrail – round bar or angle.

But recently we’ve seen the addition of a lower handrail, which is more ergonomic and comfortable.

This additional handrail makes transversing stairs much safer. There are no breaks or pinch points as you move your hand along the rail. The placement is more convenient and it just has a better feel to it.

Even better, this handrail can be added to existing walkways and platforms. If you have a heavily trafficked area or a thoroughfare on which you’d like to beef up the safety – rather than replace the entire structure, consider this simple (and cost effective) addition. Give Riggs a call, we’re here to help.

easily added to existing walkways

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

Screw Conveyor – Auger

09/19/2018RMF

The Auger Conveyor uses a rotating helical screw blade to move materials along its length. This unit moves abrasive materials from hopper to hopper then to bagging.

Notice how the abrasive material has worn down the blades. Also, material is sticking to the untreated blades. Material slides over the smaller, worn out blades making the conveyor ineffective. Jobs take longer and costs rise quickly.

This new unit has Hardfacing Wire (Lincore 55) welded to the blades to reinforce them and add durability. This surface resists sliding wear and mild abrasion. These new blades will have a longer service life.

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.

The Target Blind – Revisited

08/03/201804/17/2019RMF

Blinds, sometimes known as blanks, isolate a section of pipe for repair, maintenance or testing. There are many types of blinds as we have shown before from the slip blind, the spectacle blind to the bleeder blind.

Here we have a nice assortment of Target Blinds. Used much like the bleeder blind, the target blind is placed on the end of a pipe section rather than in the center of a section. Gauges can be placed on the valves to test the pressure in the section of piping. Sampling can also be taken from the valve if desired.

The different sizes correspond with the different sizes of piping found within the refinery.

This group of target blinds is a bit “beefier” than usual. They will be used during the permanent shutdown of a unit until the demolition of the unit occurs. There may be need for occasional venting of the piping section until the demo.

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

Explosion Proof Hatch – Pyrite Ducts

07/27/2018RMF

Here are some newly machined explosion-proof hatches for pyrite ducts.

In preparing coal for energy production, pyrite, a sulfide that contributes to air pollution and acid rain, is removed before burning. The separated pyrite is forced through ducts to waiting hoppers using high pressure fans. These ducts have negative pressure in them. If a chunk of pyrite gets stuck in a hopper then unit has to be shut down and the duct removed from the unit to be cleaned.

Photo by James St. John / CC by
Sphalerite-Pyrite

With the addition of these hatches, if a chunk of pyrite gets stuck in the hopper, it is only a temporary shut down while the hatch is opened and the material is washed out. Once the hatch is sealed, the unit is quickly brought back on-line.

These hatches have also been used as inspection doors on gearboxes, giving quick access to the internals for routine maintenance or adjustments. The locking tab on the hatches also helps keep the unit secure.

Primary Air Fans

05/17/2018RMF

Primary Air (P.A.) fans force air into the furnaces of coal-fired power plants. Rotating at 1,600 RPM, they have to be solid, balanced and reliable.

Here is a new P.A. fan. It has been welded and the center hub riveted. The welds are then inspected to AWS D14.6 Standards using Magnetic Particle Inspection.

The fans are then balanced; much like you’d balance the wheels on your car. The shafts are also balanced and a mated set is created to ensure smooth rotation and a long service life.

The Gator – First Test

04/11/201804/11/2018RMF

The Gator is a remote controlled tank cleaning unit we built for Veolia Environmental Services. It is driven into large tanks to clean the walls of hazardous materials. Its infrared lights cut through the dark and mist while recording all operations from the safety of a control booth.

This is a test of the unit running up a ramp and squeezing through a manway as it would enter a tank in the field.