Over the holidays my son asked me if I had ever been on an oil drill rig. In enlightening him as to what his old man did in the 80s I realized the story might me interesting to others, so here goes. It started with a telephone call from a purchasing engineer with the Gulf Canada Resources. He was interested … Read More
Cleaning Carbon Tanks In Carbon in Leach And Carbon in Pulp Processes
The two gold extraction processes CIL (Carbon in Leach) and CIP (Carbon in Pulp) are quite similar, both using granulated activated carbon to extract the gold from the solution. For the extraction processes to function efficiently a specific carbon granule size must be maintained. It is therefore critical to handle the fragile carbon particles in a manner that does not … Read More
Understanding How Static And Dynamic Balancing Affect Cantilever Pumps
I was recently asked to investigate a vibration in a vertical cantilever pump. The client had recently rebuilt the pump and was wondering what he had missed or done wrong. In the absence of any vibration monitoring equipment, we resorted to physical checks. With the pump out of the sump, we carefully rotated the shaft and there was no evidence … Read More
What exactly is an impeller’s “tip speed” and how do you calculate it?
Establishing an impeller’s “Tip Speed” is very useful when selecting the best pump for your application, but what exactly is tip speed and how do you calculate it? The tip speed is simply the distance that any selected point on the peripheral of the impeller travels in a set time. In other words the “speed” of that point. To calculate … Read More
Differences Between Flush and Quench In Slurry Pump Seal Support Plans
When discussing slurry pump seal support plans it seems that the terms “Flush” and “Quench” are often confused and or misused. With the concept being slightly different for mechanical seal boxes vs packed seal boxes I will separate these, discussing each in turn. Mechanical Seal The basic mechanical seal flush plan is very simple. It calls for a clear/clean liquid, … Read More
Pumping Cow Manure
I just thought I would share my latest adventure. It was quite smelly to say the least. We had a customer who bought a HS-E81-80 pump for a dairy farm. Now who would have thought that a manufacturer that produces the best slurry pumps in the world would be called upon to provide a pump for a dairy. This pump … Read More
Impeller Designs
I recently received an e-mail asking to explain what the terms “open” or “closed” referred to when discussing impellers in a slurry pump. So here it is. Although there are numerous styles/designs offered by pump manufacturers, most slurry pump offerings boil down to a variation of one of two basic designs, with a third design, slightly less common, that is … Read More
Checking The Condition Of A Submersible Pump Motor
Whether it be a submersible pump you already own or a used pump you are looking to buy, it is important to know the condition of the electric motor. A few quick checks can save you a bunch of time and or money. The most common problem in a submersible pump motor is water ingress. Whether it be entry though … Read More
To Check or not to Check?
I often receive questions as to whether a check valve in a pumping system is a good or a bad thing. Auto closing check valves are often an integral part of a successful pumping system; however, they can also be the root of many system failures. The question then becomes “when is it appropriate to incorporate check valves in a … Read More
Single Phasing in Electric Motors
Causes and Solutions to Protect your Motor I once had a customer ask me for some advice to help them come up with some ideas as to why their pump would trip as soon as it was lowered into slurry. I asked questions such as: Have you checked for proper rotation? Did you check for pluggage in the discharge line? … Read More
