My Perspective on Driven Pile Drivability Studies

I originally posted this in 2013 on another forum. Recently I had a round of correspondence with a county official in Washington state re pile drivability studies and their place in the contract process.  (If you're looking for some explanation of this, you can find it here).  His question was as follows: During the bidding … Continue reading My Perspective on Driven Pile Drivability Studies

Inclusion of Rotational Inertial Effects in Power Consumption Calculations for Vibratory Pile Equipment Presented at the Chattanooga Development Symposium

The paper Inclusion of Rotational Inertial Effects in Power Consumption Calculations for Vibratory Pile Equipment was presented last Tuesday at the Chattanooga Development Symposium. You can view this presentation in the YouTube video below. https://youtu.be/nHlQ-bQEnXg The abstract--and a clarification--are below. Abstract: Virtually all treatments of power consumption and modelled performance for vibratory pile driving equipment assume … Continue reading Inclusion of Rotational Inertial Effects in Power Consumption Calculations for Vibratory Pile Equipment Presented at the Chattanooga Development Symposium

Checking the Soviets: Determining the Eccentric Moment

This is the first in an aperiodic series on design calculations for a piece of experimental Soviet construction equipment, in this case an S-834 impact-vibration hammer. A more complete history of these machines (a co-author was one of the designers) is here. We're going to compare the calculations originally done on these machines with what … Continue reading Checking the Soviets: Determining the Eccentric Moment

Analysis of Springs with Circular Cross Section

Coil springs never were a prominent part of most Vulcan hammers, but they did appear in spots and they are an important part of machine design. In this post we'll go over the basics of these, based on Belyaev and Juvinall and Marshek (1985). The basics of spring design and nomenclature. The springs shown in … Continue reading Analysis of Springs with Circular Cross Section

Curved Beam Analysis on a Hand-Forged, Non-Rectangular Cross Section

In a recent post I discussed curved beam analysis with a rectangular cross section, and as a follow-up a comparison of that type of analysis with finite element results. Many curved beams, such as the lifting hook shown above, do not have rectangular cross-sections. This is an interesting topic, not only because of the engineering … Continue reading Curved Beam Analysis on a Hand-Forged, Non-Rectangular Cross Section

How the Saximeter Works, and Why You Can’t Use It on a Vulcan (or any other External Combustion) Hammer

One interesting device people use to estimate the output energy of a diesel hammer is the Saximeter. Originally developed by Pileco, it's a quick way to estimate the output energy based on the blow rate of the hammer. The operating cycle of a diesel hammer, in this case a Nilens hammer. The Saximeter takes advantage … Continue reading How the Saximeter Works, and Why You Can’t Use It on a Vulcan (or any other External Combustion) Hammer

Condensing Gas Furnaces: the Vulcanaire Supertherm of HVAC

Our government moves to mandate them: The new proposed rule, announced by the U.S. Department of Energy (DOE) yesterday, would require that gas-burning residential furnaces achieve 95 percent energy efficiency by 2029. The stated goal is to lower consumers' energy bills in the long run and limit harmful emissions...The DOE press release says that homeowners … Continue reading Condensing Gas Furnaces: the Vulcanaire Supertherm of HVAC

Comparing Curved Beam Analytic Analysis with Finite Element Results

As sort of a "postscript" to the earlier post Stresses for Curved Beams with Rectangular Cross Sections, let's compare these results with those from finite element analysis. For the example we'll use the example from Belyaev shown below. For this example we'll stick with Those Pesky Kilogram-Force Units that he uses. We'll use an old version of … Continue reading Comparing Curved Beam Analytic Analysis with Finite Element Results

Interference Fits and Vulcan Ram Points

As was the case with the previous post Tapered Keys and Their Use In Vulcan Hammers, the topic of interference fits between machined parts doesn't get that much coverage these days. In spite of that it's an important part of machine design in general and Vulcan in particular, especially with the ram points. Before we get … Continue reading Interference Fits and Vulcan Ram Points

Tapered Keys and Their Use In Vulcan Hammers

Vulcan's hammers have been successful because they are simple and reliable, using very basic technology to do the job. One of those elements has been the use of tapered keys. Although keys have their problems--and both Vulcan and others have laboured to replace them--it's an interesting fastening method that doesn't get much coverage these days. … Continue reading Tapered Keys and Their Use In Vulcan Hammers