High-Pressure Technology Glossary

The A-head is a load-change-free high-pressure pump head made from a forged stainless steel block, developed by KAMAT. Thanks to its stress-free design and minimal sealing points, it offers a long service life with reduced maintenance intervals. It allows full service access from the front without having to dismantle the pump head.

Advantages:

• Load-free → fatigue-free
• One-piece and forged: fewer seals, less leakage
• Service without special tools.

See also: Pump head, Modular system, M-Kopf

The loss of performance as a result of discontinuous move of the water column in the suction line. Acceleration loss has taken into account for any design of the suction line of the pump. Acceleration loss can lead to vapor pressure in the suction line and therefore to cavitation in the pump. Acceleration losses have to be taken into account for sizing the suction line.

API Standard 674 is an internationally recognised American Petroleum Institute standard for positive displacement pumps used in the oil, gas, and process industries. It sets out the technical requirements for designing, manufacturing, testing and documenting such pumps, with a particular focus on reliability, safety and ease of maintenance.

The standard is particularly relevant for critical applications involving continuous operation and high operational reliability requirements. It specifies tolerances for pulsating flow rates and vibration limits, as well as requirements for crankshaft, bearing and seal design.

More information on API 674

The rules for placing devices and products on the market in potentially explosive atmospheres are specified in Directive 2014/34/EU (ATEX) of the European Parliament.

ATEX = Atmosphere Explosible – potentially explosive atmosphere

The purpose of this directive is to ensure that devices and protective systems may only be placed on the market if they are manufactured in accordance with the state of the art in the community in such a way that they ensure the safety of people when they are properly installed and maintained and used as intended and, if necessary, of pets and farm animals as well as the observance of material assets. The potentially explosive areas are divided into Ex zones.

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Barrier or flushing fluids are used to protect seals and adjacent components. They can keep aggressive, hot or solid-containing media away from the seal packages, provide cooling and lubrication, or maintain a defined pressure in the sealing chamber. Properly designed barrier and flushing systems increase service life and operational reliability.

The base frame is the supporting element of a pump unit. It securely holds the drive unit, pump, coupling, control cabinet and other components of the power and drive train, ensuring stability, alignment and low-vibration operation.
At KAMAT, the base frames are welded in our own metalworking shop (Plant I). This enables high-quality, application-oriented design and flexible adaptation to customer-specific requirements.

The total volume throughput per unit of time at suction conditions. It includes both liquid and any dissolved or entrained gases (reciprocating pumps are not tolerating gas). For all practical purposes this can be considered the volume flow rate in the suction pipe not considering compression of water. The standard unit of KAMAT pump capacity is liters per minute also used as m³/h.

Cavitation is the formation and subsequent collapse of vapor-filled cavities when the local absolute pressure in a liquid drops below its vapor pressure—typically at constrictions, high velocities, or due to the periodic acceleration of the suction column in plunger pumps. The collapse releases micro-shock waves that cause erosive surface damage, increase noise/vibration, and impair flow stability.

Practice: Ensure NPSH margin, use short, large-bore, vented suction piping, keep speed moderate, and add a suction stabilizer if needed; limit fluid temperature and avoid unnecessary throttling.

See also: NPSH, Suction Stabilizer, Speed/Rated Speed

More Information on Cavitation

A component for vibration isolation between a pump, a device and the periphery. In pipelines, mostly a flanged part with a flow section made of flexible material, e.g. rubber. It could also just be a flexible hose line.

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Corrosion is the chemical or electrochemical degradation of metallic components. In plunger pumps, it directly affects service life, operational safety, and maintenance intervals.

Common corrosion types:

• Uniform corrosion: general material loss caused by saline, acidic, or CO₂/H₂S-containing fluids.
• Crevice corrosion: occurs in narrow gaps with low oxygen, e.g., at sealing faces.
• Pitting: localized, rapidly progressing attack, especially in chloride-containing environments.
• Stress corrosion cracking: caused by the interaction of tensile stress and corrosive media.
• Erosion corrosion: corrosion intensified by high flow velocities or solid particles.

Protection measures:

• corrosion-resistant materials (duplex/super duplex, Inconel, Hastelloy)
• coated pump heads
• replaceable valve seats and wear parts
• optimized flow geometry
• controlled operating conditions

Correct fluid analysis and material selection are essential to prevent corrosion damage and unplanned downtime.

See also: Pump Head, Viscosity, High-Pressure Valve, Pump Design,

The crosshead is the guide element between the connecting rod and the plunger rod. It converts the rotary motion of the crankshaft into a precisely linear reciprocating motion and absorbs transverse forces before they act on the sealing systems. Precise crosshead guidance reduces wear on the plunger, packing and bearings and increases the service life of the pump.

A damper is a component that reduces pressure and flow pulsations in the suction and/or pressure lines of plunger pumps. By decoupling volume and pressure, it ensures a more consistent flow rate, reduces vibrations, protects components, and improves the system's operational stability. Depending on their position and design, suction flow stabilizers, bubble traps, resonators or pulsation dampeners are used on the pressure side.

Also see: Suction Stabilizers, Pulsation Dampener

Dead space refers to the residual chamber in the cylinder that is not displaced by the plunger movement at the end of the stroke. A large dead space reduces volumetric efficiency – especially at high pressures due to the compressibility of the medium – increases pulsations and prolongs the time it takes to reach the relief or working pressure. High-pressure heads are therefore optimised for minimal dead space.

See also: volumetric efficiency, hydraulic power, pump head

A pulsation dampener reduces the periodic pressure fluctuations generated by a plunger pump on the discharge side, protecting piping, fittings, instruments, and tools. Acting as an elastic/volumetric buffer in the line, it lowers the residual pulsation at the point of use.

Sizing

• Define the target residual pulsation
• Match to the pump’s dominant frequencies (speed, cylinder count) and the local line volume at the installation point.
• Install close to the consumer or upstream of sensitive instrumentation; ensure streamlined connections.
• Consider operating range (pressure, temperature, fluid) and plan regular performance checks.

Benefits

Smoother operation, improved measurement stability, reduced component stress, and more consistent process behavior (e.g., steadier jet pattern, more stable test pressure).

See also: Pressure Pulsation, Speed/Rated Speed, Triplex Plunger Pump, Quintuplex Plunger Pump, Plunger Diameter , Water Hammer

A double-acting pump performs the pumping action in both the forward and backward movements of the plunger. This enables higher volume flows with a compact design, but requires a more complex construction.

See also: Single-Acting Pump, Plunger Pump

Drive power refers to the energy that a drive – such as an electric motor or internal combustion engine – transfers to a technical system. It is a key parameter in the design and sizing of machines, pumps, or hydraulic systems.

More information on Drive Power

A variable frequency drive controls the speed of the drive motor, allowing the volume flow and pressure to be adjusted to the process requirements. The advantages include reduced starting current, improved energy efficiency, lower mechanical stress and flexible operation. In high-pressure systems, the variable frequency drive supports low-wear and process-stable operation.

The portion of the pump that converts supplied rotary motion into linear motion used by the Fluid End to move the plungers back and forth including a gear reduction.

A high-pressure hydraulic pump is a positive displacement pump used to generate and maintain elevated pressures in hydraulic systems. It converts mechanical drive power into hydraulic power and supplies consumers such as cylinders, hydraulic motors, clamping devices, and presses with defined pressure and flow.

For very high pressure levels and demanding operating conditions, plunger pumps are commonly used. Depending on the configuration, KAMAT high-pressure plunger pumps are suitable for water hydraulics as well as oil-based and special fluids, and are applied in hydraulic systems for mining, steel production, presses, test rigs, and safety-critical applications. By combining modular pumps with matching valves, dampeners, accumulators, and safety devices, complete high-pressure hydraulic power units can be engineered based on KAMAT technology.

Also see: Plunger Pumps, Positive Displacement Pumps, Pressure

This is a high-pressure pump based on the reciprocating principle (using pistons or plungers), driven by a crank mechanism. As a positive displacement pump, it converts the rotary motion of a motor or engine into the linear motion of the pump elements. This enables fluids to be delivered at very high pressures with precise flow control.

High-pressure reciprocating pumps are ideal for industrial applications that require reliable operation, high efficiency and consistent performance, especially when handling viscous or contaminated fluids.

Also see: Poitive Displacement Pumps, Plunger Pumps, High-Pressure Hydraulic Pump, Piston Pump

More Information on High-Pressure Pumps

A high-pressure unit is a modular system designed to generate and deliver fluids – typically water or oil – at extremely high pressures, often ranging from several hundred up to over 4000 bar. These units are used in industrial applications such as hydrostatic testing, pipe and surface cleaning (jetting), and pressure calibration – across industries like oil & gas, construction, chemical, and heavy industry.

KAMAT high-pressure units stand out for their robust design, easy maintenance (no special tools needed), compact footprint, low noise and vibration, and highest material quality – entirely Made in Germany. Units are available in mobile or stationary versions and can be flexibly customized using a standardized modular system to meet specific customer requirements.

High-pressure valves are fittings used in positive-displacement pump systems to control/limit pressure and switch fluid flows. They must open and close quickly, tightly, and repeatably at high operating pressures—otherwise pressure losses, pulsation, and wear increase.

Functions & types

• Safety valve (SV) – independent last line of defense against overpressure; opens at a fixed set pressure.
• Pressure relief valve (PRV) – operational limiting/control, diverts flow into a bypass line.
• Unloader/bypass valve – routes flow pressure-free to return (filling/stand-by).
• Directional / multi-consumer valves – distribute flow and switch consumers on/off.
• Check / foot valves – ensure one-way flow and keep suction lines primed.

Design & installation

• Always provide SV and PRV separately and match settings to maximum / operating pressure.
• Choose streamlined valve geometries and piping (low valve Δp); avoid cavitation.
• Use media- and pressure-resistant materials (high-strength, corrosion/erosion resistant); ensure service access (seat/cone/ball).

Correct selection and placement of high-pressure valves improves safety, control quality, and service life of the system.

See also: Safety Valve,  Unloader Valve,  Operating Pressure, Maximum Pressure 

More Infos High-Pressure Valves

Hydraulic power is the useful power transferred from the high-pressure system to the fluid. It is calculated as the product of pressure and flow rate and is typically expressed in kW. It forms the basis for sizing the drive power and evaluating overall efficiency.

In hydrodemolition, concrete is selectively removed using a high-pressure water jet. This process causes minimal cracking and does not result in thermal damage, while protecting the reinforcement. The design is based on pressure, volume flow and nozzle geometry, as well as suitable pulsation management (e.g. damper/resonator), to ensure uniform removal. The safety chain comprises a pressure relief valve, a safety valve, and approved hoses and fittings.

KAMAT plunger pumps and pump units (KAMJET) cover the typical pressure and volume ranges required for hydrodemolition. These pumps enable precise pressure ramps and standby mode via a recirculation valve or pneumatic suction valve lift. The modular design of valves, dampers and filters supports both manual and robotic concrete removal solutions.

See also: Plunger pumps, pulsation dampers, pressure control (VFD/recirculation/SVH), safety valves

More Infos to Concrete Removal

A hydrostatic plain bearing is a type of sliding bearing in which the lubricant film between the bearing surface and the shaft is maintained by an external pressure source. The fluid (e.g. oil or hydraulic water) is pumped into pre-defined recesses or flow paths to establish and sustain a film thickness, independent of the relative motion of the surfaces. This enables virtually contact-free operation, a very high load capacity, high stiffness and low friction.

Also see: High-Pressure Pump, High-Pressure Hydraulic Pump

Hydrostatic test pumps are high-pressure systems that can be used to generate and maintain defined test pressures during hydrostatic pressure testing. An incompressible fluid, usually water, is used as the test medium. Plunger pumps are preferred for high pressures and cyclic test profiles as they allow for precise pressure ramps, consistent holding times, and reliable continuous operation.

Technical features:

• Pressure and volume flow can be set to match the standard or test volume for fast filling and sensitive pressure maintenance.
• Control and pressure maintenance features include defined ramps and plateaus, minimal pressure drop and the option of adding dampers and accumulators to reduce pulsations.
• Safety: Safety valve and pressure limitation; complete venting of the system.
• Measurement and documentation: Calibrated pressure sensors and gauges; specification of measurement uncertainty; data logging; and protocols.
• Operating conditions: - Temperature stabilisation of the test medium (influences density/volume).
  - Materials suitable for the medium.

Also see: Safety Valve, Pressure Limiting Valve, Dampener, Volume Flow

More Infos on Hydrostatic Testing 

Hydrostatic testing is a method used to verify the leak-tightness and pressure integrity of pressure-containing components such as pipelines, vessels, heat exchangers, valves, and hoses. The test object is completely filled with an essentially incompressible liquid—typically water—and pressurized to a test pressure above the normal operating pressure. The pressure is maintained for a specified holding period while the system is monitored for leaks, permanent deformation, or other irregularities.

Using water significantly reduces the risk in case of failure compared to gas pressure tests. Common terms include “hydrostatic testing”, “hydro test”, and “water pressure test”.

KAMAT high-pressure plunger pumps and pump units are used to generate accurate and repeatable test pressures for hydrostatic testing, including high-pressure and cyclic tests. Combined with dedicated valves, measuring equipment, and control systems, they enable both stationary test rigs and mobile test units. Detailed information on typical applications, pressure ranges, and system configurations is provided in KAMAT’s application section on pressure testing of pipelines and vessels.

More Infos to Hydrostatic Testing

The M-head is a robust high-pressure pump head built in modular block construction. Unlike the monolithic forged A-head, the M-head consists of precision-machined individual components connected by bolted joints. This design allows for easy replacement of individual parts while maintaining high pressure resistance.

Applications:

• Medium to high pressure ranges
• Ideal for systems requiring frequent reconfiguration or scaling

Advantages:

• Replaceable individual components
• Cost-effective and proven in standard industrial use
• Modular and service-friendly construction

See also: Pump Head, Modular System,  A-Head

The maximum pressure is the highest permissible pressure that a pump or system may briefly reach without exceeding its permissible stresses and safety limits. It serves as the basis for the design of components such as high-pressure heads, valves, hoses and fittings. The operating pressure must always be below the maximum pressure.

Mechanical efficiency refers to the ratio between the drive power supplied and the power mechanically transmitted to the pumped medium. Losses occur due to friction in bearings, gears, and seals. High efficiency means energy-efficient operation.

See also: Volumetric efficiency, Gears,

A modular system is an approach to design that enables the standardised production of technical components. The individual modules can be combined in a variety of ways. In high-pressure pump technology, for example, this principle enables plunger pumps to be adapted flexibly to different performance and application requirements, while reducing the number of variants.

Using standardised components simplifies development, storage and maintenance. Reusing proven components leads to high system reliability, shorter delivery times and more economical production. At the same time, the modular system enables precise design of application-specific configurations in terms of parameters such as pressure, flow rate and materials.

Also see: A-Head, M-Head, Pump-Head

More infos about the Modular System of KAMAT

A multi-consumer system supplies several consumers (e.g. blasting tools, process units) from a central high-pressure pump or pump station. Volume flows, pressures and switching states for individual consumption points can be individually controlled and secured via multi-user valves or modules. This allows high-pressure systems to be operated efficiently and flexibly.

Multi-pump systems can be used to flexibly expand the pressure and flow ranges. Parallel operation enables a higher flow volume or redundancy, while series operation enables a higher final pressure. To achieve optimum performance, it is crucial to implement a suitable pressure control strategy, effective pulsation management (e.g. dampers and pipe routing), an appropriate suction side design (e.g. common or separate inlets) and synchronous start/stop/speed control to avoid load jumps and resonances.

See also the topics of pressure control, pulsation dampers, and drive and automation technology.

The NPIP test (Net Positive Inlet Pressure Test) verifies that a plunger pump has sufficient positive inlet pressure margin under real operating conditions. NPIP is the absolute inlet pressure minus the fluid’s vapor pressure; for positive-displacement pumps it is preferred over classical NPSH because it directly captures dynamic inlet effects (especially acceleration head).

Objective: Demonstrate that the available NPIP during all stroke phases is ≥ the pump’s required minimum NPIP (as specified by the manufacturer), even under adverse combinations of speed, temperature, viscosity, and suction piping.

Typical procedure (concise):

• Place an absolute pressure sensor close to the inlet flange; record temperature to determine vapor pressure.
• Use high-frequency sampling (kHz range) to capture stroke-by-stroke minima.
• Test at rated/max speed, elevated fluid temperature, full flow; include suction-line worst-case.
• Evaluate instantaneous minima per stroke; report time histories with a “Required NPIP” threshold.

If margins are insufficient: shorten/enlarge suction piping, use lower-loss components (filters/valves), add a suction stabilizer, adjust allowable speed window, reduce fluid temperature.

See also: NPSH  Suction Stabilizer

NPSH (Net Positive Suction Head) describes the available pressure head at the pump suction connection in relation to the vapour pressure of the medium. For cavitation-free operation, the available NPSH value (NPSHa) must be higher than the NPSH value (NPSHr) required by the pump.

More on NPSH

Offshore Design refers to the structural and material engineering of machinery and components intended for use in marine environments such as offshore platforms, FPSOs, and coastal installations. Offshore conditions expose equipment to salt-laden air, permanent humidity, temperature fluctuations, vibration, and restricted accessibility for maintenance—requiring enhanced durability and operational reliability.

For high-pressure pumps, Offshore Design typically includes:

• Corrosion-resistant materials, such as duplex/super-duplex steels, Inconel, or coated carbon steels
• Specialized coating systems, e.g. NORSOK M-501 or customer-specific offshore standards
• Resistance to shock and vibration under maritime operating conditions
• Compact installation footprints for confined spaces or containerized units
• High uptime and extended service intervals, due to limited maintenance opportunities offshore
• Compliance with ATEX requirements, commonly found on offshore installations

An offshore-designed pump system must therefore combine high performance with robustness against extreme environmental influences.

See also: ATEX, Pump Head, Pump Design

The operating pressure is the pressure at which a high-pressure pump or system is operated in regular continuous operation. It is below the maximum permissible pressure and is defined taking into account safety, material selection and application. The permissible operating pressure is a key parameter for the design of KAMAT systems.

Overall efficiency of a plunger pump is the ratio of hydraulic output power to shaft input power. It is the product of
volumetric, hydraulic, and mechanical efficiency.

Key factors:

• Volumetric: internal leakage (packing, valves), clearance volume/compressibility; decreases with pressure, temperature, and wear.
• Hydraulic: flow/valve losses, throttling, unfavorable piping, excessive pulsation.
• Mechanical: friction in packing, bearings, and gearbox (typically very high for plunger pumps).

Practice notes: A robust suction layout (NPSH margin), proper speed, effective filtration, and healthy valve dynamics improve overall efficiency; monitoring pressure and flow rate enables trend evaluation during operation.

See also: Volumetric Efficiency, Mechanical Efficiency, Hydraulic Power, NPSH

More Information on Overall Efficiency / Pump Efficiency

The packing is the central sealing element in the high-pressure head of plunger pumps. It seals the moving plunger rod against the high-pressure chamber and prevents medium leakage. The design and materials are adapted to the pressure, temperature, medium and mode of operation. The condition of the packing has a significant influence on the efficiency, tightness and operational safety of the pump.

The packing system is the complete sealing arrangement in the high-pressure head sealing the reciprocating plunger rod against the high-pressure chamber. It consists of several coordinated packing rings and, if required, support and guide rings. Design, material selection, lubrication, flushing or barrier systems, and proper installation determine service life, leakage behavior, and operational safety.

Also see: Plunger, Stuffing Box, Wiper

A piston pump is a positive-displacement pump in which the seal is mounted on the moving piston and runs back and forth inside a stationary cylinder. Displacement is generated by (near) complete reduction of the cylinder volume; flow is controlled by suction and discharge valves. Typical traits include good suction capability but higher sliding seal friction and a different service concept compared with plunger (tauchkolben) pumps, where the seal is stationary in the head and the plunger moves through it.
Note: KAMAT pumps are plunger pumps, not piston pumps.

See also: Plunger Pump, Packing System, Positive Displacement Pumps

A submersible piston pump, also known as a plunger pump, is a type of positive displacement pump. In this type of pump, the submersible piston (or plunger) moves back and forth within a stationary packing system located in the high-pressure head. Unlike a piston pump, the seal is fixed in the head rather than being located on the moving piston. The plunger moves through the packing into the delivery chamber. This design enables very high pressures, a compact design, and easy access for servicing the seals. The delivery rate is proportional to the stroke length, plunger diameter, and speed. Pressure is generated by automatic suction and pressure valves. Typical designs include triplex and quintuplex pumps, which reduce flow pulsation.

See also: Plunger, plunger pump

The plunger is the pressure-loaded, reciprocating displacement element in a plunger pump. In contrast to a conventional piston, the plunger itself is not sealed by a moving piston ring inside the cylinder but runs through a fixed packing system in the high-pressure head. This design enables high operating pressures, compact pump dimensions, and easy access to the sealing system.

Plungers are manufactured from high-strength, wear- and corrosion-resistant materials with tight dimensional tolerances and fine surface finishes. Plunger design, material, and surface quality directly influence sealing performance, packing lifetime, and overall pump reliability.

Also see: Plunger Pump, Packing, Packing System, Piston Pumps

The plunger diameter is the outer diameter of the plunger in the high-pressure section of the pump. It directly influences the combination of pressure level and delivery rate: smaller diameters enable higher pressures, larger diameters enable higher volume flows. The selection is made depending on the desired operating pressure, medium and application.

A plunger pump is a reciprocating positive displacement pump used to deliver fluids at extremely high pressures. It operates with a moving plunger that displaces the medium through an inlet and outlet valve system. Plunger pumps are known for their energy efficiency, durability, and precise pressure control – even under the toughest industrial conditions.

See also: Plunger, High-Pressure Pumps, Positive Displacement Pumps, Triplex Plunger Pump, Quintuplex Plunger Pump

More Information on Plunger Pumps

A type of a positive displacement pump that uses a cylindrical plunger to drive fluid through the valves. The plunger reciprocates through a stationary of seals set fixed to the pump head known as packing.

Plunger pumps, by laypersons often just called piston pump, belong to the group of oscillating positive displacement pumps – one of the oldest pump types. The displacers in plunger pumps are moved/pressed by crankshafts which is integral to the pump and the pump has one or more cylinders. The displacer of this pump is called “plunger”. In contrast to piston pumps the plunger “dives” through a fixed seal into a sealed off working space, displacing the fluid. Since 1974 the company KAMAT is an experienced producer of plunger pumps in Witten, Germany. In this video KAMAT’s CEO Dipl. – Ing. Jan G. Sprakel explains the technology and some of the benefits of plunger pumps.

Positive displacement pumps are hydraulic machines designed for the continuous conveyance of fluids. The delivery volume in these machines is generated by mechanical displacement within a closed working chamber. The delivery volume per revolution remains largely constant, regardless of pressure. This makes them particularly suitable for applications requiring precise volume control or operating at high counterpressure.

Typical designs include piston, diaphragm and gear pumps. Positive displacement pumps are characterised by their high pressure capability and self-priming capacity, as well as their ability to convey viscous or particle-laden media. They are used in a variety of fields, ranging from process engineering and water jet technology to the petrochemical industry.

More Information about Positive Displacement Pumps

Pressure is the force acting on a surface (units: bar, MPa, Pa). In high-pressure plunger pump systems, we distinguish between gauge pressure (relative) and absolute pressure – the latter is decisive for suction-side issues such as NPSH.

The operating pressure is the pressure level of the system designed for continuous operation; all components must be permanently suitable for this. The maximum permissible operating pressure forms the upper design limit and may only be reached for a short time; the safety valve (independent protection level) and pressure relief valve must be adjusted accordingly.

Together with the volume flow, the pressure determines the hydraulic power and thus the dimensioning of the drive. For cavitation-free operation on the suction side, the following applies: NPSH-a > NPSH-r with sufficient reserve. Good suction conditions (short, large-dimensioned, vented pipe; suction flow stabilizer if necessary) stabilize the delivery behavior and reduce pulsation.

See also: Operating Pressure, Maximum Pressure, Volume Flow, NPSH, Suction Stabilizer, Hydraulic Power, Safety Valve, Pressure Limiting Valve

A pressure limiting valve limits or regulates the system pressure during normal operation. It opens when the set pressure is reached and diverts part of the volume flow to keep the pressure in the line constant or to relieve a pump.

Unlike a safety valve, the pressure limiting valve is primarily used to limit operating pressure and relieve the plunger pump, and is integrated into ongoing operations as an adjustable control or regulating device. If it is mistakenly regarded as the sole safety device, impermissible operating conditions may arise – therefore, functional separation and interaction with a correctly designed safety valve is absolutely essential.

Also see: Safety Valve, Plunger Pump , Volume Flow

More Infos to Pressure Limiting Valve

Pressure pulsation in a plunger pump results from stroke-by-stroke displacement. Frequency increases with speed; amplitude grows with displacement per stroke and decreases with a higher number of cylinders (e.g., quintuplex vs. triplex). Valve dynamics, gas/compressibility, and line compliance (e.g., hose sections) further affect pulsation level.
On the system side, throttling elements, long/narrow lines, and nozzles often raise the pulsation measured at the tool; countermeasures include pulsation dampeners and streamlined piping with a moderate speed window and suitable cylinder count. Note: Water hammer is a transient event (switching/shutdown spike), not the same as periodic pressure pulsation—treat them separately.

See also: Pulsation Dampener, Speed/Rated Speed, Triplex Plunger Pump, Quintuplex Plunger Pump, Plunger Diameter, Water Hammer

Pulsations are pressure and flow fluctuations that are typical for positive displacement pumps. They are caused by the intermittent operation of the pistons or plungers. Their effects can be minimized by using pulsation dampers or multi-head pump arrangements.

See also: Pulsation Damper, Plunger Pump,

Pulsation dampeners are components designed to reduce pressure fluctuations in high-pressure systems and ensure a smooth, continuous flow of liquid. They protect pumps, pipelines, and valves from mechanical stress, thereby extending the lifespan of system components. In industrial applications such as high-pressure cleaning, waterjet cutting, and pressure testing, pulsation dampeners are essential for improving efficiency, stability, and system reliability.

Also see: Pulsation, Plunger Pump

More on pulsation dampeners

Pump design refers to the technical process of selecting and dimensioning a pump based on the specific requirements of an application. Key parameters include the required operating pressure, flow rate, fluid properties (viscosity, temperature, purity), the operating profile (continuous or intermittent duty), and the suction conditions (NPSH).

In addition to operating data, structural and mechanical aspects such as material selection, sealing systems, valve geometry, number of cylinders, drive technology, and ease of maintenance play a central role in pump design. The objective is to define a pump that delivers long-term reliability, energy efficiency, low wear, and economic operation.

See also: Plunger Pump, Operating Pressure, NPSH

More Info about Pump Design

Often called lantern at KAMAT is the mechanical connection between the pump head and the gear box. It isolates the gear box and the pump head from each other in terms of fluid exchange or temperature. With KAMAT pumps it is possible to change high pressure packings, oil seals and wipers through the carrier without disassembly of the pump head.

The pump head is the central component of a plunger pump. Here, the fluid is pressurized and transferred into the discharge line. Acting as the connection between the mechanical drive (crank mechanism) and the fluid circuit, the pump head contains the main fluid-handling components, including inlet and outlet valves, seals, and plunger guides.

More on pump heads

A pump valve is a self-acting check valve used in positive displacement pumps to control flow direction. In plunger pumps a distinction is made between suction valve and discharge valve. Both are actuated by differential pressure: when the fluid pressure exceeds the opening pressure, the valve opens; when pressure drops or reverse flow occurs, it closes to prevent backflow.

Typical designs are plate, ball, or cone valves consisting of valve seat, valve body (e.g. plate or disc), spring, and cage/guide. Key performance factors are low pressure loss, fast response, optimized flow guidance, and wear- and corrosion-resistant materials matched to the required pressure range, fluid, and temperature.

A quintuplex plunger pump has five plungers and is characterised by its particularly low pressure pulsations and smooth operation. It is used in applications requiring a constant delivery rate at high flow rates, or in sensitive processes. Compared to three-plunger designs, this configuration allows for a steadier pressure curve.

Rod reversal (reversal point or dead center) refers to the moment when the plunger changes its direction of movement. Controlling this point is crucial for smooth operation and the service life of the mechanical components.

See also: Stroke, Double-acting pump, Gearbox

A safety valve is a self-opening valve designed to protect systems, components and personnel from excessive pressure. If the set response pressure is exceeded, the valve opens and releases the medium into a relief or return line until the pressure falls below the closing pressure again. Safety valves are designed as a last line of defence, must be dimensioned in accordance with applicable regulations and secured against unintentional adjustment.

The safety valve must be clearly separated from the pressure limiting valve, as it is designed as an independent, final level of protection against impermissible pressure exceedances and must not be used as an operating or control valve. Only with clearly separated functions and a design that complies with the relevant standards can the necessary system safety be achieved and the protection of components and persons be reliably guaranteed.

More Infos to Safety Valves

A single-acting pump conveys the medium in only one direction of movement of the plunger. It is simpler in design and particularly robust, making it ideal for high-pressure applications.

See also: Double-Acting Pump, Plunger Pump, Rod Reversal

Solids content describes the amount and size of particles present in the pumped fluid. Excessive solids or particle sizes above the specified limits cause increased wear on plungers, valves, packings, and seats. Proper filtration and compliance with the limits given in the pump specifications are essential for reliable operation.

Speed indicates the number of revolutions per minute of the crankshaft. It directly affects flow rate, pulsation, component loads, and NPSH requirements. Rated speed is the speed approved for continuous operation according to the pump design and must not be exceeded.

Also see: NPSH

The suction head is the difference in height between the liquid level in the storage tank and the pump's suction nozzle. A positive suction head (i.e. inlet pressure) improves the NPSH, whereas a negative suction head worsens it. Temperature, gas content and pipe losses also have an effect. The suction head should always be considered alongside the NPSH and acceleration pressure.

See also: NPSH

The stroke describes the linear movement of the plunger from one reversal point to the other. The stroke length, together with the plunger diameter, determines the volume delivered per cycle.

See also: Plunger Pump, Rod Reversal

The stroke length is the distance travelled by the piston or plunger during a complete reciprocating movement. It is usually specified in millimetres and corresponds to twice the distance between the stroke pin and the centre of the crankshaft (the crank radius). The stroke length influences the delivery volume per stroke and is therefore a key parameter in the design of high-pressure pumps.

The stuffing box is an assembly located within the pump head. Using a packing system, it seals and guides the reciprocating plunger rod from the high-pressure chamber. It accommodates packing, support rings and pressure rings, and allows a defined amount of leakage to facilitate cooling and lubrication. This leakage must be returned and vented.
KAMAT uses contact packing as standard, which is robust and adjustable. Non-contact gap/labyrinth seals, on the other hand, require very fine filtration and precise guidance. The tightness, friction and service life are influenced by the plunger surface and the packing preload.

In KAMAT plunger pumps the stuffing box forms part of the plunger/stuffing box unit (conversion kit), enabling quick adjustment of the pressure and volume flow.

The suction manifold is where the suction piping is connected to the pump head. From the suction manifold the water is supplied to each individual cylinder of the pump head. It is designed to allow smooth flow from the inlet to the cylinders and may vary in size depending of the flow of a pump.

A suction flow stabilizer is a container located at the inlet of a plunger pump. It stabilises the suction side's volume flow, enabling safe and consistent pump operation. It compensates for pressure and flow fluctuations, reduces the risk of cavitation, and protects the pump and its components from premature wear.

KAMAT suction flow stabilizers are designed for specific volume flows, pressures and temperatures, and are available in a range of sizes. Additional connection options for pressure gauges, venting, drainage, temperature and pre-pressure monitoring are available on request. Depending on the application, they are available in either galvanised or stainless steel.

The pneumatic suction valve lift allows for a controlled transition between unpressurised circulation and high-pressure operation in plunger pumps. In the unloaded state, the suction valves remain open, allowing the medium to circulate without pressure build-up. When the required minimum pressure of control air is reached, the valves close and the pump builds up the desired high pressure.
At KAMAT, the pneumatic suction valve lift is used for pumps with M or M2 pump heads (formerly MC heads), and it can replace a separate circulation valve.

Advantages:

• Clearly defined switchover point between circulation and high-pressure operation
• Reduced piping and simplified system hydraulics
• Protection of the pump and components through pressure build-up only when required

It can be easily integrated into pneumatic control and safety systems.

Flexible couplings, which are used between the drive and the pump, decouple the torque fluctuations of the oscillating pump (torsional ‘pulsation’) from the drive. This protects bearings, plungers, seals and the entire drive chain – which is particularly important if the drive is powered by a combustion engine or if the speeds are variable. The coupling is the only flexible element in the line, while the unit itself is mounted on a rigid base frame.

See also: Base Frame, Speed, Drive Power

A triplex plunger pump has three plungers working in parallel, driven by a common crankshaft. The offset working cycles produce a comparatively even flow rate. Triplex designs are the standard in many high-pressure applications, as they combine high pressures with a compact design and good service accessibility.

Also see: Quintuplex Plunger Pump, Plunger Pumpe, Pump Design

Mor Informations about Triplex Plunger Pumps

A unloader valve allows fluid to flow back to the tank without pressure when there are no consumers being supplied, or when the system is being started up or shut down gently. This reduces load peaks and heat in the circulation system.

Please note that with KAMAT, the pneumatic suction valve lift (SVH) can replace the circulation valve, enabling the pump to operate without pressure in the circulation and without a return line.

See also: Pressure control, Suction valve lift (pneumatic), Safety valve.

Viscosity characterizes the flow behavior of a fluid and directly affects suction performance, NPSH requirements, permissible speeds, and efficiency. Excessive viscosity can lead to insufficient filling of the plunger chambers, higher loads and temperatures, and cavitation, and must be considered during system and pump selection.

The volume flow is the delivery rate of a pump per unit of time and is usually specified in l/min or m³/h. It is calculated from the stroke length, plunger diameter, number of plungers and rotational speed. Together with the pressure, the volume flow defines the hydraulic power and is a key parameter for the design of high-pressure systems.

Volumetric efficiency describes the ratio between the theoretical flow rate and the actual achievable flow rate of a pump. It is influenced by factors such as leaks in seals and valves and is a measure of the hydraulic efficiency of a positive displacement pump.

Also see: Mechanical Efficiency, Plunger Pump

A water hammer is a sharp pressure pulse caused by rapid changes in flow or valve position. Possible consequences include vibrations, seal damage and measurement errors. Possible countermeasures include defined ramps (VFD), a suitable valve sequence, damping and correct pipe routing.

See also: pulsation dampener

Water jetting is a powerful process involving the use of high-pressure pumps. It uses water at pressures of several thousand bar to cut, clean or process materials with precision. Since there is no thermal influence, this process is particularly gentle on materials, making it ideal for sensitive or temperature-critical materials. High-pressure pumps ensure consistently high performance and precise pressure control. Water jetting is used in numerous industrial applications, including manufacturing and surface treatment.

More infos about Water Jetting

The wiper is a protective and guiding component located in the area of the crosshead or plunger rod. It removes dirt, dust and particles that adhere to the moving rod before they can penetrate the sealing chamber and gearbox.

In KAMAT high-pressure pumps, the wiper protects the seal of the linear crosshead movement specifically, reducing wear and thus contributing to a longer service life for the sealing system and gearbox.

Also see: Packing, Packing System