Industrial Pumps Blog

For clients, the total cost of ownership is the primary focus when making an acquisition decision.  This runs true no matter what the industry or application is involved, but whenever a decision is made the costs which should be included are not only the initial deployment or acquisition costs, but also the life cycle costs which provide a more accurate costing. Lifecycle costs include energy consumption costs, the opportunity cost associated with downtime, the cost of maintenance and spare parts.  Collating all these costs provides a Total Cost of Ownership or TCO.

The challenge is to source and implement an industrial pumps solution which minimize the TCO but achieve all the project deliverables.  Knowing what pumping principles are involved in a specific project (and therefore what type of pump is most appropriate) is essential, as is making a proper assessment of the dimensions involved.

Overall, the TO will be determined by numerous factors, some of which are under the control of the plant operator and some which are not.  Minimizing TCO involves:

• Pump optimization in respect of the liquid, especially taking into account viscosity;
• Optimization of pump system components;
• Understanding and addressing the deliverables of the pumping system;
• Optimization of the pump drive;
• Ensuring installation is optimal with minimal installation and downtime for other plant operating processes; and
• Ensuring dimensions are fully understood and are optimized.

All of these factors must be considered if TCO is to be minimized. However, it is not enough to understand each factor in isolation as they all interact to one degree or another – this means a holistic approach to the pumping process must be adopted, in order to gain the most accurate understanding of the project and the underlying cost issues.  Pumping components and solutions must be designed and implemented to work in relation to the surrounding infrastructure and also to handle the liquid or gas which is the subject of the pumping system.

The Three Gorges Dam is one of the largest engineering projects ever undertaken in the world, and certainly it is the largest dam ever.  It is not simply sheer size which makes the Three Gorges Dam special; it has a total electricity generation capacity of 22,400 Mega Watts (MW) which requires a 24/7 x 365 oil pumping system to govern the hydropower unit. Such a huge system requiring continuous operation presents a number of unique and highly challenging engineering problems.

The original industrial pump which was installed failed to operate successfully requiring them to be replaced.  Before replacements could be sourced, a detailed analysis of the pump system which had broken down had to be undertaken, including returning to the original design parameters for the electricity generating system, to understand the challenges and reasons for failure.  There was also the design challenge of having to come up with a work around solution in order to implement a modified installation to the existing infrastructure.

Only after a detailed analysis was conducted could a new engineering solution be implemented.  The new pumping system now incorporates fail safe technology together with properly loaded pumps to handle the capacity which is generated.  The replacement solution is now in situ and operating successfully.

For an energy hungry such as China, the Three Gorges Dam is only part of a series of power generation infrastructure projects which are being developed to supply energy to one of the world’s fastest growing, manufacturing based economies.  Despite the size and scale of the Three Gorges project and other energy generation projects, there is still the need to curb electricity usage in major Chinese cities today – a sign that further projects and more efficient power usage will need to be developed further.

The vacuum pump was invented over 350 years ago by German scientist, Otto von Guericke.  The vacuum pump’s first application was in scientific experiments which required the removal of gas molecules to create a vacuum or a partial vacuum. The humble vacuum pump has modern applications, but there are now several variants which use the fundamental operating principal.

Broadly, there are three types of vacuum pump:

• Positive displacement pumps;
• Entrapment pumps; and
• Momentum transfer pumps.

Positive displacement pumps continuously create a vacuum by manipulation of a diaphragm or rotary action. Positive displacement pumps are by far the most common variant of vacuum pumps in operation today. The primary application of positive displacement pumps are in fluid transfers because they actively move the fluid (hence positive displacement and because a fluid cannot be “pulled”).

The entrapment pump works by using temperature.  Cold temperatures are used to create condensation from gases and convert them into a solid state. Molecules of gas are trapped in a confined space (hence entrapment) which is known as a “cold trap”.  Here the gas molecules are turned into condensation or a liquefied state, while ionized gas is used to power an ion pump.

Momentum transfer pumps, also known as molecular pumps, work by means of a high speed jet of fluid, or alternatively, a very high speed rotor.  In either case, molecules are “knocked out” of the pump chamber and the gas molecules are transferred to the exhaust stage of the pump. There are two main types of momentum transfer pump – diffusion pumps and turbo-molecular pumps.  The diffusion model uses a jet of dense fluid such as mercury to create molecular displacement, while the turbo-molecular pump uses the high-speed rotor method. Typically, both these types of pumps work at very low pressures, i.e. 1kPa, and in both cases the pumps will fail if the gases are vented directly into the atmosphere or exhaust environment of similar pressure, then the pumps will fail, so it is necessary that they vent into low-pressure vacuum which will require the use of another mechanical pump.

Positive displacement pumps operate by trapping fluid and physically moving it through the pump to the discharge outlet. There are two principal types of positive displacement pumps; rotary and reciprocating.  In this post we will deal with reciprocating types of positive displacement pumping systems.

Examples of reciprocating pumps include pistons, hand water pumps and windmills. Though they are still in use today for certain applications, they have largely been displaced by more efficient pumping mechanisms.  However, in the 19th Century and during the height of the Industrial Revolution, reciprocating pumps played a huge role in the economic development of both Europe and the United States.

Reciprocating pumps operate by the use of a plunger, piston or some form of diaphragm.  The operation of the plunger or piston acts to create a vacuum which acts on the fluid (i.e. suction), and this moves the fluid in the direction of the vacuum. The reciprocating pump may be a “simplex” or single cylinder pump or multiple cylinders may be used.  Reciprocating pumps tend to be produced in duplex and triplex forms, though there are some examples of quad cylinder mechanisms.

In addition to the number of cylinders, reciprocating pumps are further classified by how they “fire”, i.e. the pump can be a single action suction creating and discharge mechanism or it may have a double action so that suction operates in both directions (as does discharge).

Reciprocating pumps can be powered by a variety of energy forms including water, air, steam and belt-driven motors.  Clearly, these pumps are forerunners of modern pumping systems, but they are relatively inefficient and suitable for pumping relatively small amounts of fluids, typically water.  Modern applications of reciprocating pumps include managing highly viscous fluids, such as concrete.  Reciprocating pumps tend to be chosen where there is a need for a low flow rate to be delivered against high resistance.

After the electric motor, pumps are the most ubiquitous machine in the world and as such, they have a tremendous impact on how much of an impact we make upon our environment.  We rely upon pumps to deliver clean drinking water, to deliver fuel to our car engines, to make our refrigerators and washing machines work, and so many more applications. In this instance, we refer to “greener pumping systems” as ones which use less energy or utilize fewer material resources in their construction and design.

Reducing energy consumption by pumps is a highly effective way to make pumping systems greener.    The primary opportunity to make pumps more energy efficient is in the appropriate application of pumping technology to the application.  Using pumping solutions which are not well-designed or suitable for the use to which they are being put will render the environmental cost in terms of inefficient energy consumption, inordinately high.

In addition, deciding upon an appropriate pump type is also essential for efficient pump operation generally and not simply energy consumption.  Inefficient pump operation will not only consume greater energy for work performed units, but will also result in great material consumption by the installation in respect of shortened life cycle and increased maintenance and repair materials required.

The road to greener pump solutions starts with a proper assessment of the pumping system and work which is required to be performed.  Immediate gains in pumping efficiency can be achieved by concentrating on pump sizing at the design stage.  The average pump only operates at 40% efficiency while 10% of pumps operate at less than 10% efficiency – more than half of pump installations are operating at less than 50% efficiency resulting in a huge waste of energy being consumed.

Greener pumping systems can also be achieved by focusing on the materials used in the construction of the pumps themselves.  Modern design tools allow for precise calculations of stress limits which means better material use can be designed into the construction of the pump itself.  By minimizing the amount of material needed in construction, a greener pump results however the pump’s structural strength and capacity are still within the design tolerances needed for the pumping solution to perform its job.

Increasingly stringent regulations are becoming more of the norm for the global marine industry, particularly in the areas of sulfur emission control and pollution impact upon the environment.  The European Union has spearheaded sulfur emission legislation and certain notable hotbeds of environmental legislation are following in the United States.  It is only be a matter of time before federal law and regulation ties operators to more stringent requirements and this is impacting pump design in various ways.  One key issue with pump design is the ability to self-detect and alert operators to leaks, impending failure and other prevention features.

It is not simply environmental considerations which are driving industrial pump development as on board a ship, any leak in confined space has the potential for calamity, particular in machine rooms.  Whereas previously tolerable leaks could be ignored for operational purposes, this is no longer an option if the operator is to comply with safety ratings or satisfy the commercial need to control costs.

The key commercial issue with self-detection and prevention has been to design and implement a cost-effective solution.   One issue is found in the question, “When is a leak not a leak?” – mechanical seals require lubrication over their moving surfaces otherwise the pump will quickly degrade and fail, so lubricant leakage has practically been inevitable. (more…)

Multiphase or tri-phase pumping solutions are commonly found in oil and gas fields and their application is increasing as a direct consequence of increases in drilling operations.  Multiphase pumping solutions allow for simplification of the upstream drilling operation and also provide for smaller and less costly pumping installations.

Typically, a multiphase solution will deal with all of the fluid stream characteristics using an integrated piece of machinery instead of using different, discrete equipment units.  It is usual to find twin-multiphase units in operation rather than a single, larger installation and it is not uncommon to find three-multiphase units installed in series.

Multiphase solutions also find application in midstream and upstream operations, both onshore and offshore and may be serve single or multiple wellheads.

Multiphase solutions are used to transfer crude oil and gas from the wellhead to the downstream facilities, either for further processing or in the storage farm.  The multiphase solution is capable of managing anything from 100% gas through to 100% fluid and intermediate mixtures, which may also incidentally contain abrasive detritus, such as sand from the operation as well as managing varying flow and pressure rates.  However, a major environmental attraction is that multiphase solutions substantially reduce the emission of pollutants, particularly greenhouse gases by reducing the requirement for tank venting and flaring of excess gases.

There are five main categories of multiphase pumps:

• Twin Screw – Positive Displacement (PD) – comprises twin, intermeshed screws which find common pumping application for high-gas content product or where there are fluctuating input rates;
• Helio-Axial Pumps – Centrifugal – sometimes referred to as the Poseidon Pump, this uses one rotodynamic pump operating along a single shaft;
• Progressive Cavity – PD – used in shallow or surface wells where fluids may have a high solid content (typically sand or earth);
• Buffer Tank – this is usually found upstream and eradicates variable input flow rates and also reduces the level of solid detritus in the fluid stream; and
• Electric Submersible – Centrifugal – typically used when the liquids are being pumped and are used to provide artificial lift.

Crude oil is a heavy, viscous liquid which is required to be transported from some of the most extreme and harshest environments on the planet.  Not only must crude oil transfer pumps and components be reliable and capable of withstanding environmental considerations, but the application of technology must also be appropriate to ensure smooth functioning of the pumping solution.

To achieve effective and safe operation, both the industrial pump supplier and oil operator must work closely together.

Industrial pump suppliers must be capable of delivering a broad range of pumping solutions backed by in-depth application experience.  Oil operations typically tend to be conducted in remote locations, and this aspect of oil exploration and acquisition is only likely to continue to intensify.  Oil operation isolation demands that all aspects of the technology used are robust and capable of high-availability and short maintenance cycles in order to minimize plant downtime and costs.

Oil operators are increasingly turning to suppliers who can offer a collaborative approach beyond simply delivering lower TCO’s or high reliability.  Transfer of expert and specialist knowledge from the supplier to the operator’s team is increasingly viewed as essential in order to maximize in-house utility of resources (which avoids the need to engage external, highly paid consultants and specialist third-parties for maintenance operations).  In addition, by pursuing a collaborative approach to delivering robust pumping solutions, a well of experience is built up within the client operator for use in future projects which in turn reduces overall company costs even further.

There are discrete project benefits from engaging in a collaborative approach for both partners; not oil fields are equal, and the product’s physical properties can vary significantly from field to field.  By working together on the unique crude oil product from the field in question, a unique optimal solution is more likely to be identified and implemented.  This can, and does result in significant increases in overall profitability and productivity of the field.

With over 1,100 oil mist installations world-wide, many of the world’s refineries are familiar with LSC’s technology.  However, there are many persons in the industry that are not familiar with oil mist technology.  Oil Mist is best classified as an aerosol.  It is not a Volatile Organic Compound or a vapor.  OM is a mixture of one part oil to 200,000 equal pats of air and a lean mixture that will not support combustion or explode.  The appearance of oil mist resembles cigarette smoke or steam drifting from a pump or motor through a vent line.

Oil mist is generated by passing high velocity air over or through an orifice that pulls oil into the air stream.  The high velocity air shatters the oil into particle sizes of one to three microns.  Airflow transports these small oil particles through a piping system to the equipment to be lubrication – typically overhung process pumps.

Prior to bearing application, the small particles of oil are passed through an orifice, reclassifier or mist fitting, causing the small particles to impinge on each other and grow in size.  The heavier particles are then large enough to wet the surface and provide adequate lubrication for most rolling element bearings.  It is excellent lubrication for bearing operation at 1,800 to 3,600 rpm and it is often the preferred method of lubrication for bearings operating in the 10,000 to 15,000 rpm range where splash lubrication is ineffective.  Companies using oil mist lubrication typically see their mean time between repair increases from 24 – 36 months up to 48 to 60 months.  With the average repair cost per pump $8,000 – $15,000, the reduced repair costs attributed to oil mist lubrication can have a dramatic impact on a refineries bottom line.

Until the 1950’s, food handling equipment had to be cleaned by hand resulting in excessive labor usage, high production costs and inefficient cleaning.  The advent of hardware which removed the human element resulted in higher hygiene standards and reduction in labor costs; however the process still required use of an ancillary cleaning and tank system to perform cleaning-in-place.

Cleaning-in-Place (CIP) and Sterilization-in-Place (SIP) are systems which automatically clean and disinfect food handling systems without the need for disassembly.  This translates into reduced operating costs and greater plant uptime due to reduced stoppage for cleaning.  More than this, modern CIP/SIP systems allow for cleaning to take place without stopping the entire plant as the area to be cleaned can effectively be by-passed as CIP/SIP processes take place.

Many industries benefit from CIP/SIP technology including the food and beverage, pharmaceuticals, dairy, cosmetic, personal care and biotechnology industries where there is an overriding need for the most stringent, sterile operating processes.  Under such stringent hygiene and sterile requirements, operators are not allowed to touch or enter the operating surfaces and equipment – effective CIP/SIP operations remove any need for operator handling while minimizing downtime.

The CIP/SIP hardware must also be capable of handling a range of fluid materials; a practical example is in the food industry where many materials which form part of the final product are not fluid in nature.  Many soup varieties use a range of ingredients including vegetables, noodles and croutons which the processing pumps, valves and cleaning systems must be capable of managing.  The combined requirements of hygiene, improved uptime and materials handling characteristics, demand very high technical standards and expertise in both the design and implementation phases of any CIP/SIP project.

Overall, much higher hygiene standards are achievable with CIP/SIP systems, such as those provided by Allweiler Pumps, which have at their heart, highly efficient pumping systems.  Not only are the systems more hygienic and contribute to improved uptime, they are also effective in reducing environmental impact with minimal use of water and sterilizing materials.