Bob Sheaf

President
CFC Industrial Training

Robert J. Sheaf Jr., is the founder and president of CFC Insustrial Training, formerly Certified Fluid Consultants, part of CFC-Solar Inc. CFC-Solar provides technical training, consulting, and field services to any industry using fluid power technology. 

Articles by Bob Sheaf
Troubleshooting Challenge: ABS testing setup needed low pressure

A supplier of anti-lock braking system (ABS) control modules was competing for a contract to supply the braking system for a newly designed hybrid vehicle. The vehicle manufacturer specified that the new design had to be cycle tested at several different pressures. This was a normal specification, but one of the test pressures had to be only 15 psi, with a tolerance of ±1 psi.

Troubleshooting Challenge: Appliance manufacturer has sluggish polishing machine

Troubleshooting Challenge: Telescoping double-acting cylinder failure

An aerospace manufacturer has a vehicle with a 50-ft, 4-stage double-acting telescoping cylinder mounted to the front.

Troubleshooting Challenge: Street sweeper motor shaft seals failing

Cleaning up the aftermath of Hurricane Katrina was a huge undertaking. Street sweepers were in great demand and used heavily to keep debris off the roads that were still passable. It was important to continually sweep nails and sharp objects that would fall
off trash hauling trucks and flatbed trailers.

One contractor complained that his sweepers were breaking down frequently due to their hydraulic motor shaft seals failing. The part of the circuit for the brush motors is shown. The motor on the curb side seemed to fail more often than the one on the street side.

Troubleshooting Challenge: Pressure faults and leaks in classified military project

A contractor was awarded a contract to build a hydraulic system that needed 60 gpm flow at up to 1000 psi, then a controlled flow from 20 down to 3 gpm in 12 sec, then up again to 2200 psi. It then had to return at full speed with a maximum required return pres.</p>
      </div>
<!--/ views-view-fields.tpl.php -->
  </div>
  <div class=

Troubleshooting Challenge: Cable hoisting system overheats

Many coal powered electric generating plants receive their coal via river barges. The barge pulls into a lock, and a large vertical conveyor with multiple rectangular buckets is lowered into the front of the barge to unload the coal. To remove the coal from the barge, the conveyor is lowered until it reaches the bottom of the barge. A cable attached to the front of the barge then pulls it forward while the vertical conveyor continues to transfer the coal to a horizontal conveyor system.

Troubleshooting Challenge: Smelting plant’s hydraulic ladle can’t pour the liquid gold

A gold smelting plant couldn’t get the hydraulically operated ladle to tilt and pour molten gold into ingot molds. The hydraulic system for this part of the system had its pressure and return lines connected to a central supply. All the other functions supplied by this system worked well.

Troubleshooting Challenge: Rolling mill overheating problem 1

A plating mill receives 6- to 8-ft wide coiled steel and chemically treats it with a process similar to galvanizing. The rolls have about a 4 to 6 ft OD and are unraveled like paper towels. The loose end of a sheet is fed into a pair of pinch rolls that directs the steel through several stations that wash, rinse, dry, and heat it. After it is coated and treated, the steel is then rolled back into 4- to 6-ft coils and shipped to automotive stamping plants. The complete mill can be a city block long.

Troubleshooting Challenge: Cogging Cylinder Problem
What causes erratic cylinder motion?
Troubleshooting Challenge: Low-pressure hose failing
A large forming press had a problem with a small, low-pressure return line hose. The press was used for forming a 1-in. thick flat stainless plate into a convex shape with a lip around the edges. The part is called a head and is welded to the end of a round tank that used on tanker trucks and storage systems.
Circuit design when you’re new to the game

As the economy started improving after the recent downturn, several hydraulic distributors were adding new people that sometimes got in over their head designing circuits for their customers. We received a call from a new salesman asking for our help in solving problems he was having with a system he designed and installed.

Troubleshooting Challenge: Cruise ship’s bow thrusters making docking difficult
Acruise ship was having problems docking after a cruise. If strong winds were blowing outward from the dock, the bow thrusters that moved the ship sideways weren’t powerful enough to move the ship against the wind to the dock. The captain ...
Troubleshooting Challenge: Engine block foundry’s motor circuit not rotating properly
Asand core forming machine at a cast iron foundry was experiencing a problem with its mold rotation motor circuit. Personnel could rotate a mold full of sand clockwise, but when a cycle required rotating an empty mold back to the home position, ...
New blog posts

Subscribe to the Hydraulics & Pneumatics Newsletter!

Keep up with the latest news with our newsletter

Hydraulics & Pneumatics Bookstore

Our online bookstore features most of the industry’s most popular and classic technical training books available.  

Click below to browse the bookshelves today!

Follow Us