Steel Mills

Tensile testing (aka tension testing)

RMF

We recently got to work with a local steel company to help create samples for the tensile testing of their rolled products. I wanted to look at what the samples were going to be used for once they left the shop.

 

Tensile Testing measures tensile strength, breaking strength, maximum elongation and reduction in area. There are several variations of these tests, including how the loads are applied across the materials. Below is an example testing unit. The prepared bars are held in the arms and pulled apart.

Universal Tensile Tester
CC BY-SA 4.0 Ganitz

 

These tests are performed after rolling to ensure uniformity and consistency in the product line.

 

Other reasons for performing these tests are:

– to find out how well a product will perform

– to see if it meets the client’s standards

– to test a new design

 

Pallet of Bars to be Cut
A pallet of bars to be cut for testing.

 

To perform the tests properly, the samples must be prepared for the testing device (tensometer). The ends are wider to be easily held by the device, while the center is cut thinner to allow the deformation and fracture to occur at this point. To help repeatability of testing, the samples must be as similar as possible.

 

Cutting a Bar for Testing   Cutting a Test Bar

 

The tester will apply an even and consistent force across the sample until it fractures. The elongation that occurs, as well as the amount of force that was necessary to create it, is used in the final calculations.

 

bar cut for testing

 

These calculations will help with the following tests:

Yield Strength – The point at which deformation in the part occurs.

Ductility – Percentage of elongation.

Strain Hardening – How much the part hardens with plastic deformation (plastic deformation – a yield point, once passed, is some fraction of the deformation that will be permanent and non-reversible)

Modulus of Elasticity – The point where the material will no longer return to its original length and permanent deformation occurs.

Ultimate Tensile Strength – The maximum stress that the material can withstand while being stretched or pulled before breaking.

 

thick bar for testing

Thick Bar for Testing - Side Shot

 

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

Mill Caps – Handling the Heat and Pressure of the Modern Forge

RMF

As molten billets of steel race through the plant, they are formed into their final shape through a series of ever tightening rolls and presses.

The stands that hold these forming rolls are under extreme stresses as they progressively squeeze the metals into shape; be it flat sheets, bars, round stock or rails.

At the top of these stands are the mill caps – holding the components together, absorbing constant shock and vibrations as they maintain pressure on the searing metal as it is is worked beneath it.

The original cap was a cast part. This machined version will be stronger and less susceptible to cracks and weak spots due to the possibility of bad casting. It is also made of a finer grade of metal than the old, worn piece.

Using the drawings, we will CNC a new component from a 22 inch burn-out weighing over 19,000 lbs. (Not many suppliers can provide a single piece of metal that large.) Hooks were welded on the sides so the block could be moved throughout the shop.

These higher quality mill caps will provide a better support system and a more dependable and stable stand. In the long run, they will help provide our client produce a better product and maintain a longer running mill.

 

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

What’s Up with the Price of Steel?

RMF

The cost of steel has tripled! This has been a blessing for the mills in the U.S. that had just recently been suffering. Some have been hiring and even running additional shifts to keep up with the growing demands.

Steelworks 62 – Ben Cooper – 2010
Licensed under CC

 

 

 

 

 

 

 

 

Profits are up as the price and demand for the products continue to grow – but there is a downside to all of this …

 

www.lemonloco.com

 

 

 

 

 

 

 

 

 

New fabrication and repair costs have skyrocketed. Metal quotes that our vendors once held valid for up to 30 days, are now only good until the end of the day! This makes submitting a large quote that will have to go for budgeting and long-term planning difficult for many companies.

updated angle based handrail

 

 

 

 

 

 

 

 

Jobs that we had routinely run for clients, have to be re-quoted and adjusted – upward. Some clients are putting off the work while others are trying to find inventive ways to keep the costs down. At times running equipment that should have been repaired or replaced.

 

original housing

 

 

 

 

 

 

 

The analysts see this current price jump as a bubble and believe it will continue for a short time and then drop drastically. How it will affect the mills who have been riding on the higher profits is hard to say. It’s too early to tell.

 

Steelworks 68 – Ben Cooper – 2010
Licensed under CC

 

 

 

 

 

 

 

 

But fabricators and repair facilities are hoping for a stabilization so we can help our clients get over the sticker shock they are now facing and prepare for these large capitol upgrades, outages and major repairs.

 

Malecon Sunset –  Mark McNestry
licensed under CC

 

 

 

 

 

 

 

 

 

 

 

 

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

Preparing for the Outage

RMF

Preparing for an outage can be almost as stressful as the actual event. Gathering drawings, getting materials ready, prepping vendors, suppliers and employees. Trying your best not to overlook any details.

 

construction workers
Photo by Jess Lis from Freeimages
blueprints
Photo by Fira Anuar from Freeimages

 

 

 

 

 

 

 

 

But often it’s not the big ticket items that slow or even stop production, it could be something as simple as missing shims to get a new pump to the correct height, a missing blind to close off a pipe section before adding a new unit, keys for new shafts or custom bolts you swore you ordered and now will take a week to machine.

 

bleeder blind pump shim

 

 

 

 

 

 

 

 

I’ve seen all of these, and more. The excuses are varied, who was responsible for ordering the items, I thought they were included with the quote, the existing ones should have worked with the new unit, and even – I just forgot!

 

frustrated man
Photo by Marabu from ABSFreePIC.com

 

 

 

 

 

 

 

 

So how best to avoid these situations?

– Get current manufacturer drawings for new equipment. Trying to fit a new pump on an old base never works out. Plan for modifications and additions. Make sure everyone has the same version prints. Don’t rely on old drawings someone pulled from the file or had stored on their computer. Verify you are on the same version. If you have to, create a new master set and pass them out to everyone involved.

 

parts and prints

 

 

 

 

 

 

 

– Next, and sometimes more importantly, is having a local machine shop who can respond timely, ready for such emergencies. This might require several shops of varied disciplines; one for burn outs, one for custom bolts or nuts, one for blinds and piping…

 

weld shop

lathes in machine shop

 

 

 

 

 

 

 

 

– You might want to get the shops involved early in the process, rather than late one evening when you realize something has gone wrong. They may make recommendations as to what items you may have overlooked. They may need to stock up on certain materials so you don’t have to wait to have them shipped in (and overnighted at an additional expense).

 

They may also have to juggle their schedule around to make sure they have the manpower available during the outage. Are they normally closed on weekends? Will they have a method to call someone in for a quick job? Are they in the middle of other shutdowns or production runs?

 

worker drilling

production parts being inspected
Photo by Michael Adkins photography

 

 

 

 

 

 

 

 

 

 

Some common last minute items:

  • Blinds (slip/paddle, bleeder and orifice)
  • Keys for shafting
  • Shims
  • Tube Plugs
  • Custom Bolts and Nuts (or just odd sized)
  • Non-stock metals (stainless piping or angle, brass bushings)

 

Benjamin Franklin

 

 

 

 

 

 

By failing to prepare, you are preparing to fail. – Benjamin Franklin

 

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

Shims – more than just a strip of metal

RMF

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

 

a new shim set – ready for installation

 

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.

 

don’t let your shims get this bad!

 

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.

 

a pack of new new shims

 

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.

 

custom designed shims
pump shims w-install tabs

 

 

 

 

 

 

 

 

 

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!

Welcome Gregg Nichols to the Riggs Team!

RMF

We’d like to welcome Gregg Nichols to our staff. Gregg has a combined 28 years in Industrial Distribution & Manufacturing Operations and Sales.

Gregg Nichols

 

 

 

 

 

 

 

 

 

 

His prior experience includes 5 years with Perfection Rubber (operations manager and sales), 18 years with MSC / Dolin Supply (team leader and outside sales) and 4 years with American producers (outside and industrial sales)

The business segments he previously focused on included:

  • Coal
  • Construction
  • Chemical
  • Manufacturing
  • Petroleum
  • Power Generation
  • Steel Production
Gregg and Brent Inspect a New Platform

 

 

 

 

 

 

 

 

 

Gregg’s areas of expertise include:

  • Hydraulic Hoses, Tubes and Fittings
  • Metal working – Machining – Hole Making
  • Material Handling (lifting and rigging)
  • Pipes, Valves & Fittings
  • Safety

Gregg has jumped right in and got off to a strong start. His outgoing personality and years of knowledge have been a perfect fit here at Riggs. Call him for a visit to your facility and see why he’s an invaluable asset to our team!

Is Your Scaffold System OSHA Compliant?

RMF
Ladder on Scaffold by George Hoden

Do you use long term scaffolding in place of permanent platforms? Are they stable, secure and up to the new OSHA regulations? Are you still renting your scaffolding and paying for it month after month?

FALL PROTECTION & SCAFFOLDING VIOLATIONS

remain among OSHA’s most frequently cited standard violations.*

 

 

OSHA violations are now subject to higher penalties,

this signals a 78% increase in penalty amounts.*

 

Convert your temporary, unstable scaffolding to a sturdy, permanent structure. No more rentals, no more repairs, no more guard rails that are dangerously low and above all, avoid the fear of those outrageous OSHA fines.

A Riggs Machine representative will review your current needs and outline the best options for your facility. We even offer 3D renders of the unit before construction begins so you can visualize the actual unit design.

  

Walkways – Handrail – Ladders

Riggs can not only deliver new assemblies for your facility, but update your existing equipment to bring it up to the new standards.

 

 

 

 

 

OSHA – Final Rule to Update General Industry Walking-Working Surface and Fall Protection Standards

OSHA – Top Violations

* bdlaw.com – Notes regarding OSHA penalty increases and violation citation frequency.

Roll Turning

RMF

precision cut roll

The Heart of the Steel Plant – the Rolls!
Flat rolls, grooved rolls or custom cuts, if the rolls aren’t to spec, the final product won’t be either.
Not only do bad rolls produce bad products, they can be dangerous to your facility.

roll dwg

A Pioneer in CNC Roll Turning
Riggs was one of the first shops to use CNC lathes to dress passes in rolls.
This is far superior to the old plunge cutting method. CNC pass cutting gives exacting tolerances and an exceptional finish.

cnc roll turning  cnc roll cutter

Roll Dressing
Work roll turning, with or without the chocks. Another convenience Riggs offers. Local pickup and delivery is also available.

finished roll set

Coal and Coke Facility Repairs

RMF

clinker grinder

Rebuilds and Overhauls
After years of hard service your equipment will need an overhaul. Riggs will tear down your worn machinery and rebuild it from the ground up.

Using the newest components and most modern techniques, they might run better than they have in years!

ash gate

Minimal Downtime – Fast Turnaround
Though coal and coke can be hard on your equipment, Riggs’ employees work even harder to get your machinery back on-line and keeping you operating.

component breakdown

Better Components …
A lot has changed since many of these units went into service.
Many components are just made better than the OEMs. Better springs, rings and gaskets mean more reliable equipment.

coal feeder - ready to ship      coal feeder weldment