Primeline Pumping
James Talbot
Pump Priming is the process of removing air from a pump and suction line by filling the pump with the liquid being pumped forcing all the air, gas, or vapor contained in the passage ways to escape. Centrifugal pumps require a priming after every shutdown to avoid airlock, which occurs when the impeller is full of air; and consequently, cannot produce suction lift to bring liquid into the pump. This occurs due to water being approximately 800 times denser than air, so when the pump is primed with the pumped liquid it creates a low-pressure zone at the impeller eye. Because atmospheric pressure is greater than the created low-pressure zone, liquid is forced through the piping allowing the pump to operate as rated, but when the pump is void of liquid, meaning it is immersed in air, the pump fails to create the low-pressure zone, which causes the air to circulate within the pump as there is not enough suction lift to force the liquid upward. This is known as dry running, and if done for a prolonged period of time, will induce damage and ultimately failure to the pump. In positive displacement pumps failure to initially prime leads to a mixture of air and liquid entering the pump which could cause cavitation, a phenomenon where vapor bubbles form and expand on the suction side of the pump. Upon reaching the high-pressure discharge side of the pump, the bubbles collapse violently producing vibration and deterioration to the pumping elements.
Self-Priming pumps evacuate air from the suction side at startup before commencing its normal pumping mode. This offers the potential for increased operating efficiencies in applications where pumps are used for a variety of repeated yet intermittent operations.
Self-Priming pumps from Mitchell Lewis & Staver are design for fast priming, dependable performance, easy serviceability, and are available in the follwing configurations: S.A.E., Frame Mount, and Close-Coupled Electric Motor Drive.
Reference: 1. Agilia Volumetric Infusion Pump Instructions for Use.
Reference 2: Sossai D., et al (2016). Efficacy of safety catheter devices in the prevention of occupational needlestick injuries: applied research in the Liguria Region. J Prev Med Hyg.
M46441960
Standard Pump Set with convertible piercing pin, roller clamp, calibrated silicone pumping segment with SafeClip, downstream pinch clamp, needle-free port, rotating male luer lock.
M46445475
Primary Pump Set PVC free with non-siliconized convertible piercing pin, pinch clamp, backcheck valve, needle free port, roller clamp, calibrated silicone pumping segment with SafeClip, downstream pinch clamp, needle-free port, rotating male luer lock.
This article was co-authored by Anthony "TC" Williams. Anthony "TC" Williams is a Professional Landscaper in Idaho. He is the President and Founder of Aqua Conservation Landscape & Irrigation, an Idaho Registered Landscape Business Entity. With over 21 years of landscaping experience, TC has worked on projects such as the Idaho Botanical Garden in Boise, Idaho. He is a Idaho Registered Contractor and a previously Licensed Irrigator in the State of Texas.
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Water pumps will run out of pressure and stop working if turned off for an extended period of time, such as over the winter. In order to get the pump working again, it needs to "primed": water needs to be flushed back into it and forced through in order for it to create enough pressure to begin pumping again. Although methods vary slightly for different types of water pumps, the steps below will show you the basic steps of how to prime this type of water pump.
When it comes to priming your pump there are a lot of different ways to go about it and a lot of different products. There is no right or wrong way of it, but certain situations may call for a little bit more lubrication than others and that is where mortar clay, also known as fire clay, does a fantastic job of priming out your hose for those long distances pushes. 90% of the time we prime with fireclay, it is just a no brainer. Especially if you are pumping in an area that uses a lot of crushed aggregates like here in California. You really need that extra lubrication.
Where do you prime on your pump? Do you prime via the hopper? Or do you prime through your reducer? There is only one right answer here. Or at least there is an answer that will, without fail, work a whole lot better than the other. We recommend priming your hose starting at your reducer. We know the book tells you to prime in the hopper, but for a line pump, break the reducer off and pour your prime directly into the hose through the reducer. This maximizes coverage on the inside of your hose, and it goes directly to where it is needed most.
You are going to use about half a bag of fire clay per mix. Fill your bucket half way with water, then add some fire clay and give it a good mix. Keep on adding fire clay to the water and mixing until the consistency is between pancake batter and chocolate milk. Add clay and water until you get that consistency. Not to thick, not to thin.
With the ASI check valve, priming is easy. Open the pump outlet to release backpressure on the pump, and turn on the pump. Your pump will prime itself, even if the head and intake lines are completely dry. You won't need to use syringes or draw-off valves to prime your pump.
Because of the rapid and repeatable closure rate of the valve, the ball returns to the seat and seals before solvents have a chance to flow back through the valve. The result is a flow rate that is extremely repeatable and accurate, which means more repeatable retention times.
The ASI check valve will not crush, crack or leak due to high pressure. We designed the ASI cartridge so that loads are transmitted through the valve casing rather than through the seat, as in conventional valves. The result is a valve that can withstand up to a 10,000 PSI continuous operating pressure, and will never fail no matter how much you tighten the housing (go ahead and try it -- it's guaranteed!). High pressure valves, up to 15,000 PSI, are also available.
ASI check valves we ship must pass three stringent tests before it is shipped.
These tests are by far the most stringent in the HPLC industry, and indeed it is unlikely that any other valves would even pass these tests. But we do all these tests because we know how important it is to make sure that when you put a new valve in your pump, it will perform properly. After all, HPLC is hard enough as it is without worrying about your check valves!
This test uses a special pump test fixture that simulates an HPLC pump to verify that the valve is self-priming. After the test pump and intake line are purged of water, the valve must operate well enough so that the pump can draw water from a reservoir that is 36 inches below the pump intake. If the valve fails to prime, or "skips" even once during this test, it is rejected. This test not only guarantees that the valve will prime, but also that the valve will perform properly even at very low pressures, where most other valves do not work well.
2) High Pressure Leak Test
The valve is pressurized to 12,000 PSI and tested for leakage. Valves that exceed 50 nano liters per minute are rejected. This test not only insures valve integrity at very high pressures, but it also insures that the valve will still function properly even when the customer inadvertently over tightens the valve housing. We do not monitor nitrogen bubbles to measure leak rate, because a liquid can leak due to capillary action whereas gas will not. Besides, the chromatographer is pumping liquids, not gas!
The valve is pressurized to 500 PSI and tested for leakage. Valves that exceed 50 nano liters per minute are rejected. Most valves have difficulty closing and sealing properly in the absence of the large closing forces due to high pressure. ASI valves are designed so that they do not require any backpressure to operate properly, and this test verifies it.
When it's time for routine maintenance, you only replace the cartridge, not the entire assembly. The ASI cartridge costs no more than most conventional valve rebuild kits, and you won't spend time chasing balls all over the lab bench.
With Wastecorp, you get a host of options to customize your dry prime pump the way you need it. Select from diesel, electric or natural gas motors, sound attenuated enclosures, trailer or skid mount, float regulator systems and much more.
For pumping in residential areas or where reduced noise is critical, Wastecorp offers the Trash Flow TVP Husher Series. This sound attenuated lockable enclosure reduces noise to 68 dBa @ 7 M TIER 4 FINAL ENGINES Trash Flow engine driven pumps use Tier-4 final engines. Select from Deutz, CAT or John Deere diesel engines.
Wastecorp adheres to the highest quality dry prime pump manufacturing and reduced environmental impact. The Trash Flow is ISO 9001 and ISO 14001 certified. The best part is, your dry prime pump is manufactured close to home.