ourpump.com blog

In today’s upstream and midstream oil and gas environment, screw pumps are playing a larger role in what has traditionally been a centrifugal and reciprocating pump market. This is due in large part to technological innovation by screw pump manufacturers and the industry’s need to pump heavier crude oils. Both twin screw and three screw pumps are successfully operating in multiphase, heavy crude oil and crude oil/water emulsion applications.

The oil and gas industry is producing, transporting and refining more unconventional, heavier grades of crude oil from places such as Canada, California, Mexico and South America. Crude oil from these areas is highly viscous, often requiring diluent, steam or other stimulation just to flow the oil from the reservoirs to the pipelines. These nontraditional grades of crude oil are ideally suited for pumping with a screw pump.

Depending on the actual application, either twin screw or three screw pumps are used in crude oil pipeline services. Three screw pumps are typically found boosting pressure from laterals to the main pipeline, while twin screw pumps are predominantly utilized in the main pipeline boosting stations. The primary advantages of screw pumps include the ability to handle a wide range of viscosities; centrifugals can vapor lock while pumping diluent blended crude oils and become extremely inefficient when pumping crude oils heavier than 250 cSt. Screw pumps have extremely low pulsation, eliminating the need for pulsation dampeners or complicated pipeline support systems required by reciprocating pumps.

Three Screw Pumps

Three screw pump designs are generally capable of flow rates exceeding 1100 gpm and differential pressures up to 1700 psi. The pump consists of three rotors, one power and two driven; one externally lubricated bearing capable of handling thrust loads induced by high inlet pressure; one balanced mechanical seal; a liner; a casing and a bearing/seal housing. The power rotor (coupled to driver) performs the pumping work, while the idlers act to seal off the pumping chambers. The torque is transmitted to the driven rotors by a rolling contact. The pumped fluid creates a barrier between the rotating elements, preventing metal-to-metal contact of the rotating elements. The liquid film also supports the rotors in the liner, eliminating contact between the rotors and the liners.

As crude oil enters a three screw pump, it fills the suction pumping chamber of the screw set; as the screws turn, crude oil is conveyed from suction to discharge. This positive displacement action simply moves a volume from suction to discharge, as if it were an infinite stroke piston without the need for complicated internal porting and valving.

In most cases, three screw pumps are used in applications where sand and particulate have been removed from the crude oil (i.e. pipeline grade crude oil).  However, since some particulate may have survived the crude oil settling process, most pumps are available with alternative liner coatings to prevent premature wear, and the rotors are normally hardened.

Three screw pumps usually boost pipeline lateral pressures to the main pipeline that flows to a refinery or terminal. The main pipelines usually require higher flow rates and pressures, which is best accommodated by large twin screw pumps. Today, twin screw pumps have flow capabilities exceeding 11,500-gpm and differential pressures to 1,400-psi.

Twin Screw Pumps

Twin screw pumps are hydraulically balanced, pulsation free and deliver a given volume from suction to discharge, meeting whatever back pressure the system puts on the pump. The pump has two rotors, one drive and one driven, and relies on the pumped fluid to fill the clearances between the rotors and rotors and liner. The pumped fluid seals the individual pumping chambers of the screw profiles, allowing the pump to maintain prime. In a rigid rotor design, the liquid acts as a sealing mechanism only and does not act as a bearing support for the rotors.

The rotors are supported on both ends by bearings, and torque is transmitted from drive to driven rotor via timing gears. By eliminating rolling contact between rotors, as is the case with three screw pumps, twin screw pumps can handle everything from water to heavy crude oils.

In most designs, the timing gears and bearings are external to the pumped fluid. The timing gears are oil lubricated, while the bearings are lubricated by grease or oil. Depending on differential pressure requirements, the bearing and timing gears may require a forced lube oil system to properly dissipate heat and improve overall component reliability.

Since there are at least four bearings in a twin screw pump, there are four shaft penetrations and four mechanical seals. Seals are available in both single and double seal configurations, depending on the actual service. Single seals are typically used for crude services, while double mechanical seals with a barrier fluid system are also available.

Twin screw pumps are increasingly popular in the midstream market, where their ability to handle high viscosities allows operators to pump colder or use less diluent. This is especially evident in ongoing pipeline projects bringing heavy Canadian crude oil to the American Market.

Multiphase Applications

The evolution of twin screw pumps has led to their implementation in multiphase applications. Twin screw style pumps dominate the upstream market in multiphase applications due to their operational flexibility and economical installation. Multiphase pumps boost the untreated flow stream produced from oil wells to downstream process or gathering facilities. This means the pumps handle 100 percent liquid to 100 percent gas (with recirculation) and every combination in between. These pumps are packaged for land-based, offshore and subsea applications.

Multiphase pumps are typically found in the following services:

• Lower well head pressure-As reservoirs mature, their natural pressure declines and production decreases. Multiphase pumps are able to boost the flow line pressure, allowing increased production flow rates, while bucking downstream line pressure.  By drawing down well head pressure, additional production will occur as the inflow to the production tubing increases.
• Reduced facilities-Rather than separating the gas from the liquids, treating the phases and then compressing and pumping the individual phases, multiphase pumps handle untreated well flow with one piece of equipment. By utilizing one piece of equipment, economic justification is significantly higher for remote single well production and well cluster development with centralized process facilities.
• Flow assurance-Multiphase pumps deliver a constant flow at a given speed regardless of system pressure. By changing the pump speed, operators can optimize the flow rate and inlet pressure, thus boosting total reservoir recovery, improving end of life production and reducing paraffin or hydrate buildup.

Current multiphase pump designs deliver up to 330,000-bpd (total flow) at differential pressures up to 1,200-psi. Given the current trend toward deepwater development, the oil and gas industry has recently identified the need for multiphase pumps capable of flows up to 600,000-bpd (total flow) and differential pressures exceeding 2,400-psi.

The operational flexibility, higher efficiency and robustness of screw pumps make them ideal candidates for an increasing array of applications within the oil and gas industry. Ongoing development of screw pump technology will only broaden their use in multiphase, crude oil, emulsion and produced water services.

Barbecue is a very delicious food, people in different countries around the world have their own different ways of barbecue. However, it is difficult to avoid scorch in the babecue. Some people think it is more delicious when the meat scorched a little, but the study shows that it is harmful to health because the scorched meat contains cancer-causing substances.

So a company has developed this water-cooled barbecue. It’s principle is very simple that the traditional barbecue stick is made into hollow metal pipes, and then use circulation pump and condenser to make the cold water circulating in the barbecue, to reduce its temperature, thus avoiding the scorched.

This kind of Screw Pump is produced by  HG Machinery Group Co., Ltd.
This twin screw pump can transfer various fluid medium without solid, and high viscosity paste medium. Twin screw pump has wide availability and reliability, no matter lubricating or not, and no matter corrosion or medium with gas and liquids.

Parameter:
1. Capacity: 0.5-2000m3/h
2. Pressure: 0.1-3.0MPa
3. Viscosity: 0-100, 000Cst
4. Temperature: -30-250 Degree Centigrade

The leading features:

1. Deliver arious medium smoothly without and pulsation. There are medium to be pumped throughout in the working elements ad sealing liquid which guaranteed by the construction of pump casing. All of the pump possess high self priming ability and can deliver the liquid mixture with gas or oil.

2. The high suction performance ling very low NPSHR was guaranteed by the special design of pump

3. Adopted the external bearing which lubricated individually, so can deliver various non-lubrication medium.

4. Adopted synchrinous gear, there is on metallic contact between rotating parts, there is no dangerous even dry running in a short time.

5. Various construction completely such as horizontal, vertical and casing with liner, and so on. The pump can handle various clean liquid without solid grain, low or high viscosity medium, even can deliver some corrosive medium with a correct material selection.

6. Suction of the pump is at the flank and discharge is on the top, the pump has small cubage, so it is especially used to the place of small space, such as ship.

Fluid motion and control solutions provider Flowserve has won an order of approximately $8 million for pumps from Shell Malaysia Exploration & Production to aid in the oil recovery efforts for the St Joseph field, located in the South China Sea.

The St Joseph field comes under the North Sabah 1996 production sharing contract. Shell and its co-venturer Petronas Carigali are the production sharing contractors of the Malaysian national oil company Petronas with Shell being the operator.

The order was booked with Flowserve in an earlier quarter in 2009 via a Malaysian company, Enserv Sendirian. Flowserve barrel pumps will be used on the redevelopment project to inject seawater into the field to boost oil extraction.

Tom Ferguson, president of Flowserve Pump Division, said: “This is another example of the world’s leading energy companies relying on Flowserve to help them increase their production capabilities.

“Our customers are responding to increasing global demand for oil, which is driving continued infrastructure investment. Flowserve is well-equipped to meet these needs through our extensive product offerings used in the upstream business, and our service facilities located throughout the Asia-Pacific region.”

This is a very usful invention for people who offen go out for camping or survey.  In the field, we can’t find water that can drink although there are a lot of lush vegetation surrouning. If you have this portable water purifier, it will become better.

You only need to find a water source, then repeatedly squeezing the pump, about two minutes late, the special suction device can absorb water and expel through the pipes at the other side, ultimately. The build-in filtration sterilization system can ensure the water is safety. And it can prevent the iodine-deficiency diseases because adding a small amount of iodine to sterilize. Each portable water purifier can absorb and filter 5 liters drinking water at most.

This portable water purifier has passed the test of  London School of Hygiene and Tropical Medicine.

It’s cost £ 30.

Consider a typical sewage collection system. At the initial point of discharge, water first flows (by gravity) into a network of (sloped down) drain pipes, which gradually intercept a larger main pipe. Eventually, all this water needs to be lifted to a sewage wastewater processing plant.

The lift varies from several feet to hundreds of feet in some cases. To accomplish this eventual lift, there are several options:
1. Archimedes Screw

Archimedes screw is the oldest known pumping method, and it is rarely used today. The obvious benefit is its simple design, with no seals or packing to worry about. However, it requires significant space to accommodate the necessary low angle of incline, which also increases weight substantially. Typically, only one bearing near the discharge (drive) side is provided, so the entire rotor sits cantilever at a tight clearance required to keep water from flowing back.

Eventually, the rotor sags through the clearance and wears the bottom trough, requiring frequent-and rather expensive-repairs. When a second (lower) bearing is provided, it is lubricated by grease, which-due to submergence-eventually washes out and is difficult to reduplicate. Removal of the unit for maintenance is also difficult due to weight and inaccessibility.
2. Self-Priming Centrifugal Pumps

Self-priming centrifugal pumps are common, mostly for relatively low flow applications (under 1,000-gpm or so). Like any other pump, it has pluses and minuses. Maintenance is easy since the pump sits on the surface, and trash can be removed by the access ports at the side of the casing. Priming is achieved by:

a. Foot valve

b. Check valve

c. Auxiliary vacuum pump evacuation of the inlet air

Both (a) and (b) options are the Achilles’ heel of the method, and a vacuum pump adds complexity to the system. However, if these issues are understood and pumps regularly and properly maintained, a reliable operation results. If an install-and-forget maintenance is practiced, these applications become a problem after three to five years, when wear opens clearances and priming no longer looks or works as good as promised in the glossy paper brochure.
3. Vertical Sump

Vertical sump design solves priming problems by submersing the pumping element under water. A long shaft connects it to a surface-mounted electric motor, which keeps it from getting wet. The maintenance of packings or seals is easy since the pump does not need to be pulled for repacking service. However, with a long shaft comes an alignment problem, unbalance or wear of the line bushings. Lubrication of bushings can be problematic, due to plugging or breaking of the long (and often flimsy) grease tubing. When tubing, bushings or impeller require maintenance, the entire unit needs to be pulled, which can be an issue for hard-to-access places.
4. Submersible (Wet) Pumps

Submersible (wet) pumps have an electric motor directly coupled to a pump. The entire unit is compact and relatively light, which makes it acceptable for relatively low depth wet wells (10-ft to 20-ft) at horsepower typically under 30-hp. Submergence of the motor, while a benefit, can also be trouble. To ensure water does not get to the motor windings, a double mechanical seal, filled with oil, is installed. As the impeller wears out (wastewater applications can be nasty!), unbalance and vibrations eventually tend to deflect the cantilever shaft and fail the seal.

Given this issue, submersible pump motors are typically made with better quality stator windings as compared to dry, surface application motors. Even after being flooded, the windings continue to function without shorting for some time. Moisture sensors are provided to detect, warn and alarm, but unfortunately, many operators do not have these connected-or disconnect them on purpose-to avoid nuisance alarms, and thus set the units on a road towards eventual undetected failure.

Even for a perfectly maintained submersible pump, with no impeller wear and resultant unbalance to consider, a mechanical seal life has a finite lifespan. While the secondary seal sees a better environment (clean oil), the primary seal is in direct contact with dirty sewage and eventually wears. While the exact value of such seal life depends on the application, it will likely not significantly exceed five years on average, so the pump cannot be viewed as install-and-forget.
5. Submersible (Dry) Pumps

Submersible (dry) pumps are similar to the wet submersible except that they are installed in the dry well, and connected to the wet well via suction piping. Servicing and pulling such a pump for maintenance is easier with simpler, obviously cleaner access. The issue of mechanical seal life, however, remains the same as for the wet submersibles. Since cooling of the motor is no longer done by submersion, dry submersibles require circulation of a portion of the pumpage through the cooling passages of the motor housing, which can clog these passages with dirty pumpage and overheat the motor.
6. Dry Well Sewage Pumps

The expense of constructing a dry well next to a wet well is often justified by the elimination of a long shaft (as in (3)) or the dangers of flooding the motor windings (as in (4) and (5)). Such installation looks no different than any other surface-mounted pump with a vertically oriented shaft coupled to the motor shaft. Packing or mechanical seals are a matter of choice and preference, with decisions on that very similar to regular surface-mounted pumps.

The main concern is the potential of flooding the entire pumping station, in which case a dry-designed motor fails quickly. Any corrective action is difficult until the entire station gets pumped out on emergency service.
7. Dry Well U-Jointed Shafting Pumps

Dry well U-jointed shafting pumps solve the concern of possible station flooding. However, all issues of longer shafting come into consideration. Typically, two, three or even more segments of the pump-to-motor shafting are present, with pillow blocks guiding the shafting along the way. Alignment of such shafting is critical. Just as critical is a need to balance the shafts and (preferably) the entire shafting train, with balancing machines designed to accommodate very long shafts (a difficult or expensive process). Lubrication of the bearings of the U-joints as well as pillow blocks is also critical, and needs to be followed by the proper preventative maintenance procedure. If neglected, high vibrations and failures would be the norm, not an isolated event.
Recommendations

There are several methods to lift water to the surface, each with pluses and minuses. None allow an install-and-forget attitude. The modes of failure, critical path to failure and root cause for each of these are different. By understanding the fundamental principles and applying proactive maintenance and operating strategies, you can prevent or significantly reduce failures.

Which of these methods works best for you? What are the issues you may have had and overcame by implementing this methodology? Let us know. Pumps & Systems and Pumping Machinery present this series to help build awareness and knowledge of how these alternatives work and when. Don’t fear the pitfalls-instead, understand the potential issues and apply the best options for your application.

As always, a parting quiz! Which other method of water lifting is common and what are the benefits and drawbacks of it? The first three people who answer correctly will get a free pass to a Pump School session.

Post so many things about pump, Now let me show you some fantasy pics that nothing to do with pumps.The British photographer, Richard Heeks,has great interesting in taking photos of soap bubbles. Recently he got crazy about “Death of Soap bubbles” — it means take photos of the moment that the bubble disappears.The following pictures is he photographed, the moment is very beautiful.

The bubble is about to be burst

the moment when the finger touch the bubble

The bubble is about to disappear

The bubble disappeared completely

A gas station pump burst into flames after a truck backed into the pumps. The fiery explosion threatened a small child - and the whole incident was all caught on video.

NewsChannel 5 reporter Jeff Tang talked to the man who saved the day.

Each day, Casey Kahasay adds to a remarkable streak when he shows up for work at his Shell gas station on the corner of Tiny Town Road and Fort Campbell Boulevard in Clarksville.

Since 2006, Casey has not taken a vacation - not even on a weekend.

“I’ve never had a day off,” he said.

Casey deserved one after what happened at his store Sunday night.

“I was nervous,” he said. “I never had that experience before.”

Just after 10 p.m. Sunday, one of Casey’s regular customers stopped by to fill her tires up with air. As she walked into the store for change, the truck started moving backwards with her 2-year-old child in the back.

“I see the truck moving back and it hit [the pump],” Casey said.

Video surveillance showed a burst of flames behind the truck.

Casey sprang into action. He told the woman to grab the child while he brought out fire extinguishers.

“The flame was from the pump to the truck - to a little bit higher,” said Casey.

As he fought the fire, witnesses like Rich Palleschi watched in horror.

“I was fearing the worst - not just the pumps, but the tanks underneath. Plus, I run a [fireworks store} right across the street,” said Rich.

It took three extinguishers and a garden hose, but Casey held off the flames long enough for firefighters to arrive and finish the job.

“That’s Casey. That says ‘Casey’ every day. I’m not surprised by it. He doesn’t want a pat on the back for it - that’s something he would have done for anybody,” said customer Al Ellison.

So why did Casey risk his life for a stranger’s child? He has his own children - ages 7 and 4.

“That was my life. I work hard for this store because of these two kids,” he said.

Amazingly, no one was injured during the explosion. By mid-afternoon on Monday, the other pumps were back in working order at Casey’s Shell station - and his attendance streak continued.

“Still, I’m going to work - got to keep going,” he said.

Police advise children should not be left in a vehicle by themselves when adults go into a store - even if just for a brief time.

Spray gun for pumping wine

Bartender can make various patterns when they are pouring a whisky in the bar, but we can only do such things in ordinary way. Don’t worry, this wine gun is prepared for ordinary people to have a funny pumping wine way.

Its appearance is designed as a pistol, comes with holsters.You only need to fix the fitting in the bottle holsters, and then squeeze a few force supporting the air pump above, you can spray the wine through the wine gun.

A interesting wedding, pump bride, pump bridegroom and pump priest. So funny! The hand pump get married. Wish them be blessed with love and happiness forever! Cool!