Pump repair is a significant portion of our daily routine. And those pumps include all types, brands, and sizes. And, of course, it's not just the pump that we're talking about, but the repair of the associated electric motor is also of prime importance to you, and to us.
It starts by a diagnosis of the problem by either you, us, or a coordination of our collective efforts. Once we know (or think we know) the real issue, the decision has to be made as to whether the pump needs to be pulled or can be repaired "on site". We do some explaining of the "field service" type of work on pumps in that topic page on our site. Click here to be taken to that "Pump Field Service" page.
Once the pump is in our shop a lot of mechanical checks are made to ascertain the pumps mechanical condition; like shaft and seal dimensions, impeller condition and size, casting condition (any cracks or deterioration), and numerous other tests and checks. Everything is recorded to help us make the proper decision on the full repair.
One thing we find is a deterioration of the "sealing" mechanism. This seal can be "packing" or a "mechanical" seal. If it's packing, we ALWAYS replace the packing with new, but further check the packing gland and shaft surface for extensive wear or damage. When it comes to "packing" and the normal wear of the shaft surface, we have a couple solutions. First, we can "metalize" the shaft surface with a "harder" material, or depending on location on the shaft, we can make a "shaft sleeve" of a harder steel. In this case, we turn down the shaft to even the surface, then press on a sleeve of steel and finally, re-machine the surface to it's proper dimension. This "may" save us making a complete new shaft due to seal wear. If the seal is a "rotating mechanical seal", the seal face and body will almost ALWAYS be replaced. While the seal spring doesn't usually weaken, the spring and bellows is part of the seal package. The seal "face" and "body" are the points of contact and need to be replaced as they wear.
Seals come in a myriad of materials for different applications and fluid being pumped. The least expensive seals have the stationary portion made of "ceramic" and the rotating portion made from a "carbon" type of material. More exotic seals are made of Silicon Carbide, Tungsten Carbide, Ni-resist, GFPTFE (Glass Filled "Teflon"), Metals, Elastomers, and Nitrile. All of these seal materials exist based on the reaction of the seal seat material with the fluid being pumped.
A really beneficial thing for our customers is the ability of A.R.&E. to work with a couple of our vendors to design and "retro-fit" pumps with "rotating mechanical seals". A pump may have been designed and built with packing glands and graphite based packing as the seal material. We all know that the packing glands need to be monitored regularly and "tightened" slightly as the packing wears and the "leakage" becomes too aggressive. We can eliminate that maintenance issue by retro-fitting the pump with the mechanical seal. The casting is machined to accept the new seal profile, the shaft is modified to accept the rotating portion and the pump is reassembled with the new seal in place. It's a real benefit to our customers when it comes to the savings in maintenance time and headaches.
While it doesn't happen too often, there are times when impellers need to be replaced. Usually, we're able to obtain replacements from the manufacturer, but, there are also times when (due to the age of the pump) the manufacturer no longer exists or it's simply an impeller that is no longer stocked by the factory. It's these times that we partner with a vendor who can "re-cast" the impeller and machine it to the exact same dimensions as the original. This is invaluable for these obsolete pumps that have "outlasted" the manufacturer!
Pump impellers come in all sizes, shapes, materials and types. Open, Closed, Semi-closed, Semi-open, Mixed Flow, Axial Flow, etc. You name it, and some pump company has probably called one of their impellers by that name! But they all have a purpose. Some are made to pass larger diameter "solids" while others are designed to NOT pass any solids. The vanes are flat, curved, some look like a starfish while others look like a space ship! So selecting a replacement impeller is NOT something that is done lightly. A lot of communications take place between us and the manufacturer (or design vendor) if the manufacturer is no longer in existence. And proper material is critical based on the fluid that is being pumped. We don't want to select a particular alloy metal that is high in copper or brass content, only to find out that it's going to be pumping some chemical that will react adversely with the composition.
Pump repair entails significant mechanical checks and a knowledge of the pump's application too. If the pump wasn't designed to pump the particular fluid that it is being asked to move, it could be a disaster waiting to happen. We've experienced pump impellers that look like "a lace tablecloth" because the chlorine concentration was too high for the bronze alloy from which the impeller was cast. A new impeller made of "cast iron" solved the problem.
Pumps come is all sizes, types and makes, too. And Apparatus Repair & Engineering, Inc. can handle them all. Vertical Turbine, Centrifugal, Submersible, Fresh Water, Waste Water, High Pressure, you name it... we can help you maintain your system and keep the water flowing. Just give us a call, we're here to help.