Multisafe Double-Hose Diaphram Pumps

Welcome to Feluwa

FELUWA Pumpen GmbH has at its base in excess of 100 years‘ corporate history. In 1901, the parent company was established in Neuwerk/Mönchengladbach as a foundry and expanded in 1931 by the addition of a machine factory, based in Cologne. At that time, the company focused on the production of equipment of fire, air and water technology.

The company name FELUWA is de- rived from the German words for the former business operating areas “fire” (FEUER), “air” (LUFT) and “water” (WASSER).

After a relatively short period of time, the company started concentrating on pump technology. In 1960, the company moved to Mürlenbach in the Eifel area. The integration of FELUWA Pumpen GmbH into the ARCA Flow Group in November 2000 provided the opportunity for further global growth. For in excess of 80 years, ARCA Regler GmbH has been one of the leading manufacturers of control valves, pneumatically activated actuators and positioners. With a diverse range of control valves, pumps and level indicators the ARCA Flow Group is firmly established in various fields of operation, such as chemical, petrochemical, power plants and synthesis gas plants, oil and gas, mining, food industries.

The continuous process of innovation and development of FELUWA Pumpen GmbH has been subject to multiple high-ranking recognition and awards.

The total company land area exceeds 100,000 m2, including more than 9,350 m2 of building area for production and office facilities. FELUWA is continuously expanding and investing in new machinery and production halls in order to ensure constant and

optimum quality standards.

Although hose diaphragm piston pumps already represent a significant technical innovation with several thousand units being well proven, consistent further development has been pursued with the MUL- TISAFE® double hose-diaphragm process and transportation pump. Basically, it is a hermetically sealed, leak-proof, oscillating displacement pump with double sealing of the wet end from the hydraulic drive end and the environment by means of two hose-diaphragms which are arranged one inside the other. The flat diaphragm is fully abandoned.

MULTISAFE® pumps utilise an overall diagnostic system for permanent condition monitoring of primary and secondary hose- diaphragms (by means of pressure sensors), check valves (FELUWA Valve Performance Monitoring System – FVPMS), suction pressure as well as hydraulic and gearbox oil temperature. Double hose-diaphragm pumps are characterised by unique design features and advantages, which are de- scribed in detail in this brochure and put this pump ahead of any other diaphragm pump design.

The conversion of the rotary motion of the motor output shaft into a reduced axial reciprocating action of the pump piston or plunger is achieved by powerful combined FELUWA stroke and reduction gearboxes or by a combination of FELUWA crank drives with separate gear units. Both drives are available in various ratings for a maximum power transmission of 3,500 kW. Design and development of these units are based on high reliability and long service life.

Fabrication, assembly and factory performance tests are carried out by a well-educated and trained expert team. Innovative fabrication and machining methods, proven material qualities and calculation systems for component and design strength ensure that customers may rely on high availability even under the most arduous of conditions. In order to offer maximum safety, finite element method (FEM) is applied for dimensioning and design.

All bearings of driving and crank shafts are designed as large antifriction bearings with an expected service life of 100,000 hours plus. All crank shafts of our crank drives are made of forged raw mate- rial to ensure highest operating safety and performance.

Check valves rank among the key com- ponents of oscillating displacement pumps.

With FELUWA MULTISAFE® double hose-diaphragm pumps and hose diaphragm piston pumps, the suction and dis- charge check valves are to be considered as the sole real wearing parts. For this reason, the achievement of utmost lifetime is paramount for valve design.

By means of the latest CFD methods FELUWA check valves are individually adapted to the application, both with regard to flow velocity and the selection of material and flow geometry.

Depending on the application, the check valves are either carried out as single or double ball, cone or plate valves.

FELUWA MULTISAFE® double hose-diaphragm pumps are typically characterised by easily removable check valves of wafer design. This valve design not only ensures linear flow path throughout the pump and valves.

By means of jacking bolts it also allows for easy withdrawal of the complete valve assembly like a cassette without prior removal of adjacent elements. In order to facilitate maintenance, bigger valves from design size 137 are designed with a swivel- ling style holder. Removal neither requires specialised staff nor special tools.

Big size valves are additionally provided with the patented FELUWA Quick Change System, which allows for replacement of the inner valve parts without previous removal of adjacent components or piping in less than 30 minutes. The valves are subject to hydraulic fixing only. For maintenance, opening and closing are effected by means of a hand pump, which permits minimum downtime for maintenance and guarantees maximum availability.

FELUWA Valve Performance Monitoring System (FVPMS)

For early recognition of wear in delivery valves, FELUWA has developed specific diagnostic equipment.

The measuring principle is capable of detecting leaks, even if the loss of output is still less than 1.5 %.

By means of the FVPMS diagnostic system, the operational safety and availability of pumps is significantly increased, since wear is precisely localised and detected at an early stage, which allows for specific forward planning of service and repair.

Loss of hydraulic fluid (VL, VÜ, VB) is automatically compensated by FELUWA pumps. For these situations the pumps are provided with a unique mechanical leakage control and compensation device within the hydraulic chamber. This system operates fully automatically, neither requires a separate oil pump nor a control system and is more- over not subject to wear.

During the suction stroke, the diaphragm (either hose-diaphragm or flat diaphragm, depending on the pump type) is drawn to- wards the hydraulic chamber of the piston or plunger. If the hydraulic oil volume de- creases due to leakage at the piston/plunger seal, the diaphragm will actuate a control disc, which in turn opens the compensation valve via a lever. Further backward movement of the piston/plunger causes a vacuum in the actuation chamber, since the diaphragm cannot move any further. As soon as the vacuum exceeds the setting range of the compensating valve (make-up valve), the valve opens. The actuation fluid (VL, VÜ, VB) that had been displaced into the oil reservoir during the delivery stroke is replenished during the increased suction stroke. By this means, the missing volume of hydraulic flu- id (VLE) is replaced in the hydraulic chamber. Since the compensating valve cannot open unless the leakage control valve is mechanically opened by a lever, it is ensured that the diaphragms cannot be overstretched.

Each pump head is provided with an in- dividual, easily accessible pressure relief valve in the hydraulic fluid. This valve is set to the exact nominal pressure required during the works test run of the pump. If an over-pressure situation becomes evident in the hydraulic fluid, i.e. due to a closed dis- charge sluice valve, the pressure relief valve will open, thus relieving hydraulic fluid (VÜ) into the hydraulic oil reservoir. From this reservoir the oil is automatically returned into the pump chamber via the leakage compensation valve. The relief valve protects the pump as well as the gearbox from overload which may arise from an erroneously closed isolating valve or from a blocked discharge pipe etc.

Pressure relief valves are also available with type approval and with lead seal.

A bypass system which functions in the same manner as the pressure relief valve is fitted to the pump as an option for short- term flow control. Essentially, with each delivery stroke of the pump, an infinitely adjustable portion of the hydraulic oil (VB) displaced by the piston/plunger is diverted into the hydraulic oil reservoir. Since the volume being displaced by the piston/plunger onto the diaphragm (either hose-diaphragm or flat diaphragm, depending on the pump type) is reduced by the volume being diver- ted into the hydraulic oil reservoir, the out- put of the pump decreases accordingly.

The bypass control is only designed for a relatively low driving power up to 5.5 kW or for short-term control (e.g. during system startup). Alternatively, brief opening of the bypass valve during pump startup generally enables relatively rapid bleeding and diaphragm positioning in line with the design.

Atypical characteristic of oscillating displacement pumps is the hydro-dynamic independency of the delivery flow from the pressure and vice versa. The reason for this feature is due to the mechanics of pressure generation by means of a displacement piston which prevents backflow and thus an escape of the displaced volume into the pipework.

This principle allows for the achievement of extraordinarily high hydraulic efficiencies of up to 96%. Conversely, the oscillating movement causes undesirable flow fluctuations and pressure pulsations. In order to ensure high efficiency of pulsation dampeners, the volume of moved liquid columns has to be kept as low as practicable.

For this reason, pulsation dampeners are always located close to the pump heads, i.e.

Directly above the discharge valves or below the suction valves, respectively.

To avoid pressure pulsations, an array of different pulsation dampeners is employed. Dependent on the actual working conditions, traditional pulsation dampeners (pressure air vessels) with air or gas cushion or so-called hose-diaphragm pulsation dampeners (PULSORBER) with nitrogen-filled accumulators are applied.

In-built FELUWA piston compressor

When using standard air vessels or hose-diaphragm pulsation dampeners, the attainable residual pulsation depends on the com- pressed gas volume above the liquid column within the pressure vessel. With air vessels, however, there is a constant loss (solution) of gas at the contact surface of the conveyed fluid, which reduces the dampening volume accordingly. The compensation of this loss within the air vessel requires periodic refilling by means of costly monitoring and filling devices equipped with shut-off and control units.

For this purpose, FELUWA has developed an ingenious and most effective ‘’inbuilt piston compressor”.

Foroperatingpressuresintherangeof≥40 bar and products which do not allow for the contact of air or gas, considerably more efficient diaphragm pulsation dampeners are applied.

The FELUWA hose-diaphragm pulsation dampener PULSORBER consists of a hose-diaphragm pulsation dampener and a bladder-type accumulator. The newly developed and more flexible PULSORBER 900 is made up of a roller diaphragm accumulator, which is able to cover higher ranges of operating pressure. Both systems offer all the advantages of traditional air vessels.

With each discharge stroke the displaced volume that exceeds the average flow is stored within the attached, hermetically sealed nitrogen accumulator. The stored volume is then released during the suction stroke and thus compensates the inevitable flow fluctuations.

Efficient diagnostics for mechanical and plant engineering

FELUWA has developed unique diagnostic systems which allow for supervision of the most important parameters. As a consequence, operators benefit from predictive maintenance, increased availability of the pumps and reduced operating costs. Optional direct linking of the pump in standard configuration with the control room permits remote diagnostics as well as coordination of maintenance with the operating schedule.

Diagnostics for hose-diaphragms: Hose-Diaphragm Guard (HDG)

Whereas traditional diaphragm piston pumps require conductivity measurement systems, permanent condition monitoring of MULTISAFE® hose-diaphragms is ensured by means of pressure switches, pressure gauges or contact pressure gauges. In the event that one of the hose-diaphragms leaks or fails, either product or actuation fluid will penetrate into the unpressurised intermediate space. The resulting build-up of pressure is led to the condition monitoring system, which in turn immediately provides a signal with manifold processing options. Nevertheless, operation can be maintained with a single hose-diaphragm until the system allows for scheduled shutdown and repair.

Diagnostics for check valves:

FELUWA Valve Performance Monitoring System (FVPMS)

Permanent condition monitoring of individual check valves is effected by means of acoustic

sensors which are fixed to the outside of the valve casing. They are not in contact with the product and easily retrofittable. The sensor is capable of detecting leaks, even if the loss of output is still less than 1.5 %. By means of the FVPMS (FELUWA Valve Performance Monitoring System) diagnostic system, the operational safety and availability of pumps is significantly increased, since wear is precisely localised and detected at an early stage, which permits specific forward planning of service and repair. Furthermore, the system allows for partial replacement of the valve trims in dependence on the respective wear rate.

For early detection of faults and with the objective of ensuring maximum availability, FELUWA supports the redundant nature of MULTISAFE® double hose-diaphragm pumps by means of an overall diagnostic system. Touch panels, which are integrated into the control cabinet, give the pump a transparent character and provide the operator with information on current operating parameters and the condition of fundamental parts. Bus systems link the touch panel to local process control, whereby Ethernet provides best conditions for communication and control of system frequency converters, PLC, touch panels and the FVPMS (FELUWA Valve Performance Monitoring System).

The pump can either be controlled via the frequency converter panel, the FELU- WA touch panel of the local control or via client’s DCS system with setpoint setting (via analogue input 4 to 20 mA). Touch panels provide time-related recording and direct or remote insight into check valves (via FVPMS), primary and secondary hose-diaphragms (via HDG), suction and discharge pressure (via SG and transducer), hydraulic and gearbox oil temperature (via TG), stroke rate, pre-compression of accumulators as a part of pulsation dampeners, oil lube systems of crank drive and intermediate gear (including temperature, pressure and flow), motor (including measurement of torque, absorbed power and FELUWA pump speed), transformer and frequency converter (variable frequency drive).

The Tailored Remote Maintenance Tool

The FelWebGuard (FWG) system allows for remote PC access to the control unit of the pump, which enables the operator to access the control unit via the Internet and view all the current data. In addition, a safe, bidirectional VPN conduit can be set up for remote access to the control unit. All data and trends can be checked on a web inter- face, so that the planning of maintenance and smaller issues can be solved by remote action.

The system is linked to the Internet. In the event that actual values differ from programmed nominal values, the system will email an according notification to a FELUWA service technician. The system not only allows for higher availability and productivity, but also for a reduction in service costs.

The Internet – medium for data transport: In times of “Industry 4.0” FELUWA increasingly focuses on wireless data communication and the users benefit from the new prospects resulting thereof.

If multiple pumps are being operated in parallel and are discharging into the same piping, intelligent electronic crank shaft coupling helps optimising phase shifting of the pumps. Residual pulsation can thus be reduced to a minimum.

The advantage of pump synchronisation for plants is obvious: Not only the pump itself is protected, but all downstream equipment accordingly. Thanks to the resulting reduction of life cycle costs, operation of the whole plant will become more efficient and economic.

One pump serves as master pump. The control unit calculates and controls the required phase shifting depending on the number of pumps.

Pump synchronisation requires a control unit, a frequency converter and a transmitter system to determine the crank angle for each of the pumps.

In comparison to typical bladder-type accumulators, the FELUWA PULSATROL 900

With roller diaphragm accumulator offers a unique advantage: The nitrogen cushion is automatically and individually adapted to the operating conditions by means of the Pump Condition Guard SMART. The position of the roller diaphragm is detected by an inductive transmitter. Based on this position, a coefficient of operating pressure and precompression can be calculated. By means of this index number the control unit is able to determine whether increase or decrease of the pre-compression and filling (V2) or bleeding (V1) of nitrogen is required.

The FELUWA PULSATROL is, therefore, not sensitive to operating conditions which deviate from the design layout and allows for a reduction of the uniformity coefficient to less than 0.5 % (p to p).

Pumping of heterogeneous mixtures and fluids containing coarse contaminations calls for custom-tailored solutions to ensure permanently trouble-free operation.

With traditional diaphragm pumps there is the risk of excessive stretching of the diaphragm in the pump head or suction valve due to sedimentation so that it may even be pressed into the discharge check valve, which inevitably results in diaphragm failure.

In order to avoid disadvantageous sedimentation, MULTISAFE® double hose-diaphragm pumps literally turn the traditional pumping principle upside down, which means a flow from the top to the bottom (Fig. 1). The cylindrical shape of the diaphragm with maxi- mum linear flow lines panders to the flow behaviour and avoids the settling of solids.

Fluids in aseptic process technology re- quire pumps which provide maximum cleanliness and biological safety. FELUWA MULTISAFE® double hose-diaphragm pro- cess pumps in aseptic design meet the necessary purity criteria and FDA regulations in terms of fluid-contacted materials. Designs with EHEDG conformity are available upon request.

Some media require a minimum temperature if they are to retain their positive flow characteristics. In the event of a temperature drop, they will become very viscous, solidify or crystallise. Also in terms of extreme pumping temperatures the modular system of double hose-diaphragms includes a great variety of options, such as

• Designs with ribbed casing area (convector)

• Designs with cooling or heating jacket

• Designs with double hose-diaphragms and additional flat diaphragm

Conveyed media with entrained gas or air must be compressed during the pumping action in order to avoid a loss in flow rate. By means of a so-called dead space reducing cylinder in the hose-diaphragm, the volume of the fluid chamber is reduced to minimum. Thus, entrapped gas bubbles are automatically compressed and the hydraulic efficiency of the pump is optimised.