The 17-hectare Navy Annex site consists of a parking area and buildings ranging from four to five storeys high. The Navy Annex was built in 1941 to be a temporary warehouse facility, but was converted to federal office use after the Pearl Harbour attack.
It served as Marine Corps headquarters for more than five decades, as well as providing office space for numerous navy personnel. It was also used extensively during the renovation of the nearby Pentagon before and shortly after the 9/11 attacks.
Demolition Services Inc, headquartered in Manassas, Virginia, specialises in demolition, abatement and hazardous materials projects in residential, commercial/industrial and government applications.
The company, founded in 2007, offers 45 years of combined key personnel experience in structural, selective, marine and implosive demolition, as well as field management services, site excavation and renovation and site development.
DSI currently services an area that includes, but is not limited to, Virginia, North Carolina, Washington DC, Maryland, West Virginia, Delaware, New Jersey, New York and Pennsylvania.
?The Navy Annex is not the biggest or most involved project we?ve ever done,? DSI owner and president Ron ?Boots? Feather said. ?But it is indeed a massive job. We have complete responsibility for the total demolition of all the buildings, inside and out, and disposal of all materials. When we?re gone from here, we?ll leave a flat, empty site ready for cemetery grounds preparation.
?Virtually all annex materials will be recycled ? crushed stone, metals, everything. Practically nothing will go to landfills. A tracked Powerscreen XR400S primary jaw plant and a tracked XH320SR horizontal impact crusher plant are the key components of the recycling operation.
?The crushers are producing 21A roadbase, also called RC6. We?ll use a little of it ourselves for various backfilling applications on other projects in the area. All the rest is being sold to contractors.?
RUNNING TO THE LIMIT
?We work our crushers hard,? DSI general supervisor Justin ?Bulldog? Stanley said. ?We run them to the absolute limits of everything Powerscreen claims they can do ? and sometimes beyond. This is tough, dependable, high performance equipment.
?But the key to maximum performance of any equipment is the operator. We get maximum tonnes per hour because we?re putting quality equipment into the hands of expert operators.?
?The equipment/operator factor is a big part of being able to bid jobs competitively and still be profitable,? Feather said. ?Another major factor is downtime, especially unplanned downtime. Over the years I?ve had minimum downtime with Powerscreen equipment and practically no major unplanned downtime. That?s crucial because unplanned downtime is often the difference between profit and loss.
?Before I started DSI, I worked for other companies and had very good experiences with Powerscreen equipment. Based on that, I purchased a Powerscreen XH250 impactor plant for DSI several years ago and we?ve had no issues with it whatsoever. It?s currently at work at our demolition project in Hampton, Virginia.?
DSI has 30 pieces of equipment and 40 employees, including two full-time mechanics. The mechanics are normally very busy, so equipment operating crews are generally the people performing normal maintenance procedures.
?This is one of the areas where our equipment shines,? Feather said. ?The maintenance is simple ? we just strictly follow the manufacturer?s recommendations. Well maintained equipment is dependable, high production equipment with a long service life.
?Our crews love this equipment and they treat it like they own it. You can imagine how important that is.?
Feather said the distributor was often as important as the equipment. He has worked with Powerscreen Mid-Atlantic, headquartered in Kernersville, North Carolina, for about 12 years ? including before he started DSI ? and has found the company to be knowledgeable, dependable and able to provide excellent service on a timely basis, especially in a pinch.
He added that Mid-Atlantic?s rental fleet was another vital factor. He said he was basically concerned about four things: do we have the equipment we need, in good working condition, delivered to us on time and at a fair price? Mid-Atlantic did all that, he said.
JAW TO IMPACTOR
For crushing on the Navy Annex job, Feather said DSI adopted the Powerscreen XR400S jaw as the primary crusher feeding directly to the XH320SR impactor.
?Some recyclers will use an impactor as the primary or even the only crusher, depending on the project and materials. We?ve found on this job that using a primary jaw greatly increases our overall crushing efficiency and doubles the life of our impactor blow bars.
?We?re working with a lot of very large pieces of concrete rubble, and much of it is loaded with steel. The jaw crusher breaks down the large rubble to minus 127mm and frees up much of the steel before feeding the impact crusher, which then finishes the process by shattering the rubble to roadbase size and leaving the metals clean and ready for sale to metals recyclers.?
?We use medium chrome blow bars,? Stanley added. ?We?ve found it to be better for metals and rubble on this job than manganese or ceramic. And one of the really great things about the Powerscreen XH320SR impactor is that it is actually a self-contained combination of crusher, screener, return conveyor, and stacker.
?The return conveyor sends oversize material back to the crusher inlet. This helps minimise the number of machines we need for our crushing operation.?
?A prime feature of the XR400S jaw plant is the hydraulic release,? Feather said, ?which provides overload protection. It prevents damage to the crusher by uncrushable objects such as metal and unduly large rubble.
?The crusher simply pops open, we remove the obstruction and we get on with production instead of shutting down for crusher repairs. Some other features of Powerscreen crushers that I really value have to do with dust control, safety shutdowns and Scania engines for prompt response, high performance and fuel economy.
?Powerscreen?s fast set-up is good, too. For example, the XH320SR impactor came to our Navy Annex site directly from a ship in Baltimore harbour and was set up and running within a half-hour after it arrived.?
LEAN AND MEAN
When DSI bids for work, the company is often bidding against much larger companies. Feather said that was actually one of DSI?s advantages.
?We run lean and mean. We?re very flexible, we can react quickly to the unexpected, we have no bureaucracy, we all work and we all share the load. In fact, sometimes you?ll find Justin and me out running equipment or whatever is needed in a specific situation. We have no ?feet on the desk? people at DSI.
?You?re always dealing with the top people when you do business with us. Our family name and reputation are on the line with every job so we pull out all the stops and do our level best all the time.
We always make good on what we promise. And we?re ?above? on every job, with regard to making spec, being on or ahead of schedule and within budget. Our contract for the Navy Annex job requires completion in 330 days. We?re well ahead of that so far.?
The Powerscreen XR400S primary jaw plant is designed for medium scale operators in quarrying, demolition, recycling and mining. Basic features include up to 400 tph, a hydraulic folding feed hopper with boltless fixing system, a hydraulic tilting conveyor system, efficient direct drive, a high swing jaw, a height adjustable product conveyor and a hydraulic folding extended hopper. Numerous options are available.
The Powerscreen XH320SR is a mid-sized horizontal impact crusher designed for excellent reduction and high consistency of product shape for recycling, demolition and quarry applications.
Standard features include efficient direct drive, up to 317 tph, a bolt-in cartridge grizzly with 42mm nominal spacing, a load management system to control feeder speed, a hydraulic overload protection and adjustment, four-bar rotor and twin apron design, PLC control of crusher speed, an independent under-crusher vibrating pan feeder and double-deck 11? x 5? post-screen. Numerous options are available.
?When you buy equipment,? Feather said, ?you?re buying two things: a manufacturer and a dealer. With Powerscreen, we?re very happy with both.? In Australia, the Lincom Group distributes Powerscreen plant and equipment.