The burks BKS/JXM series chemical dosing pump

Introduction

The BKS series Metering pumps are suitable for metering corrosive and non-corrosive, non-abrasive media. The pumped medium must strictly comply with the medium properties specified in this manual. If this Metering pump is used in a potentially explosive environment as specified, a special explosion-proof version must be customised.

Safety

Warning: using this pump for other purposes, or operating it in an unapproved environment and under unapproved working conditions, is regarded as unreasonable use and is not permitted. Chemicals may be hazardous; pay attention to the warnings on the labels and handle them with care. Follow the instructions for each chemical; do not assume chemicals of similar appearance are of the same type; confirm the safety of the chemical; we accept no responsibility for damage caused by feeding the wrong chemical.

1. During installation, operation and overhaul of the pump, the general safety instructions in this manual must be observed. Therefore, before installing and starting the pump, the installation engineer and other relevant qualified personnel/operators must read this manual carefully, and the manual must be conveniently available at the installation site at all times.
2. Personnel responsible for operation, maintenance, inspection and installation must be appropriately qualified for this work; when operating or approaching the Metering pump, wear work clothes including gloves and glasses; chemicals and supply tanks must be placed out of the reach of children and other persons.

Performance

The Metering pump is suitable for conveying corrosive and non-corrosive liquids at temperatures of -30~100 °C and viscosities of 0.3~800 mm²/s, with a metering accuracy within plus/minus 1%. Plunger Metering pumps are simple in construction and economical in price; diaphragm Metering pumps are absolutely leak-free and highly safe, suitable for conveying all kinds of flammable, explosive, highly toxic, strongly corrosive, strongly irritating, radioactive and valuable special liquid media (explosion-proof motors must be fitted in explosion-proof locations). The flow is adjusted by an "N"-type shaft adjustment structure; the flow can be adjusted steplessly from zero to the maximum rated flow, and the pressure can also be adjusted freely from normal pressure or even negative pressure up to the maximum allowable range.

Operating Environment

Permissible ambient temperature 0 °C to +40 °C; permissible storage temperature -20 °C to +50 °C; permissible air humidity (maximum relative humidity, no condensation): 70% at 40 °C, 90% at 35 °C. The installation site must be covered! Ensure that the enclosure protection rating of the motor and pump is not affected by atmospheric conditions; pumps with electronic equipment may only be used indoors! Never install outdoors! Warning, danger: hot surface! Pumps with AC motors may become hot; leave at least 100 mm of space above the fan cover! Minimum pressure on the suction side: 1 bar.

Materials

A typical pump head assembly consists of the liquid end, the diaphragm and the inlet/outlet cartridge check valves. This assembly is the only part of the pump body that contacts the pumped medium, so its maintenance is essential to the performance of the pump. Pump head assemblies of different materials can be provided: stainless steel, polytrifluoroethylene, polytetrafluoroethylene, molybdenum-dititanium, etc.

Storage

Storage of the pump for less than 6 months is short-term storage. Recommended storage steps: 1. Store indoors at room temperature in a dry environment; 2. Take preventive measures as required by the operating environment (such as adding a protective film inside the original packaging) to isolate it from the outside; never store it in a humid environment for a long time; 3. Carry out a full inspection before start-up, then start the pump according to the instructions in this manual; 4. In addition to the short-term storage steps above, for long-term storage, power the motor every 12 months and run the pump for at least one hour; during this operation there is no need for fluid in the pump head, but the inlet and outlet must be open to the atmosphere. After 12 months of storage, the warranty does not cover parts that age over time, such as seals, gaskets and packing.

Maintenance

Before any maintenance on the pump and pipelines, disconnect the pump from the power supply, confirm that the shut-off valves are closed and the system pressure has been released, and take the necessary steps to ensure that the hazardous liquid contained cannot leak out or come into contact with the operator; protective facilities must be provided. Before dismantling, check carefully to ensure there is no pressure in the system.

Pipeline Installation

1. To protect the Metering pump pipelines and process equipment, install a separate system safety valve to avoid unnecessary losses from exceeding the rated working pressure.
2. Shut-off valves and pipe joints (or flanges) on the inlet and outlet pipelines allow the check valves to be inspected without draining the pipeline; the size of the shut-off valves should match the connecting pipe size. Ball valves can be used preferentially because they restrict the flow the least.
3. The inlet strainer, Y strainer, pump head and check valves easily collect dust and other solid contaminants, and any accumulation of contaminants may cause malfunctions. Therefore, when installing the pipeline, fit a filter before the inlet pipeline shut-off valve and the pump inlet valve; its size should be determined by the flow rate and the expected contamination; a filter screen of 80–100 mesh is usually recommended.
4. Vacuum gauges and pressure gauges on the inlet and outlet pipelines are used to check system operation; the pressure gauge should be installed together with a shut-off valve so that it can be isolated and protected when not in use.
5. The weight of the pipeline must not be supported by the valves or pump head components, because the resulting stress may cause leakage; support the pipeline with separate brackets so that no external force or torque is applied to the pump.
6. Use a sealant chemically compatible with the materials inside the pipeline assembly; users of sealing tape should take extra care not to seal the thread head of the inlet pipe, and ensure that the old sealing tape has been completely removed from the threads before reuse. All new or existing pipelines should be flushed clean with a clean liquid (compatible with the materials) and blown dry with air before being connected to the pump. Clean the debris in the pipeline system before start-up to ensure the check valves work properly; this is an essential preparation.

Inlet and Outlet Pressure Requirements

Inlet pressure: although the Metering pump has a certain self-priming capability, use flooded suction (i.e. suction pressure above atmospheric pressure) wherever possible. Place the pump as close as possible to the suction-side storage tank or liquid source, with a suction lift of about 3 m or less; if this requirement cannot be met, the pump cannot provide reliable and accurate flow. For self-priming installation, it is recommended to install a foot valve at the lowest point of the inlet pipe, and at the first start-up it may be necessary to fill the pump with the corresponding liquid first for the pump to run normally.
Outlet pressure: all Metering pumps are designed for continuous operation at the rated outlet pressure. If the system inlet pressure is greater than the outlet pressure (a situation sometimes called "gravity flow"), the pump will produce additional flow (siphoning), which reduces accuracy and causes uncontrolled metering overflow. To avoid this overflow, the outlet pressure must exceed the inlet pressure by at least 0.35 bar; if necessary, this pressure can be achieved by installing a back-pressure valve on the inlet pipeline.

Installation Diagram

Installation Tips

To facilitate venting of the Metering pump head, install a ball valve (11B) on the bypass line (back to the dosing tank) immediately after the discharge valve; if the discharge line is long, install a check valve (12B) on the discharge line.

Points to note when installing the suction line: keep the suction line as short as possible and avoid tangling; use large bends and avoid sharp angles wherever necessary; always install the suction line rising towards the suction valve; avoid loops in the line, which may produce air bubbles.

If the pumped medium is a non-degassing medium with a viscosity similar to water, the pump can be installed on the tank (mind the maximum suction lift; use flooded suction wherever possible); prefer an overflow suction port; when pumping media with a tendency to settle, fit a filter (13B) on the suction line and keep the suction valve a few millimetres above the plane where sediment may form.

Suction-End Installation Notes

If the suction line of the metering system exceeds 1 m, depending on the metering flow it may be necessary to install a suitably sized pulsation dampener (4B) immediately in front of the suction valve of the pump.

Discharge-End Installation Notes

To protect the pipeline system, install a pulsation dampener (8B) at the discharge end when the rigid pipe exceeds 3 m and the hose exceeds 5 m.

For pumping degassing and viscous media: overflow suction port. To protect the metering pump and the discharge line from overpressure, install an overflow valve (6B) on the discharge line.

When the metering medium flows out openly, or the back pressure is below 1 bar, install a pressure loading valve (7B) at the outlet or immediately in front of the injection unit; a positive pressure difference of at least 1 bar must be ensured between the back pressure at the injection point and the metering medium pressure at the pump suction valve. If this cannot be achieved, install a pressure loading valve (7B) on the discharge line.

To prevent siphoning, install a pressure loading valve (7B) on the discharge line; if necessary, also install a solenoid valve (14B) on the suction line.

Pipe Connections

Warning: to protect the metering pump from overpressure, install an overflow valve on the discharge line; use only the specified types of pipeline! Keep all pipelines free from tension! Keep the suction line as short as possible to avoid cavitation! Use large bends and avoid sharp angles wherever necessary; when handling chemicals, observe the safety instructions of the chemical manufacturer! Ensure the compatibility between the pump and the actual pumped medium; the metering liquid must flow in the direction opposite to gravity! Caution: the resistance of the parts in contact with the metering medium depends on the medium, its temperature and the working pressure; ensure that the parts in contact with the medium will not react chemically with the metering medium under working conditions!

Motor Connection

Observe the direction of rotation of the motor! A fuse matching the rated current of the motor must be provided by the user; if the pump is used with a frequency converter, the jumpers in the terminal box must be set according to the conversion wiring method.

Start-up Preparation

Start-up checks: check that the rated voltage on the pump nameplate matches the local supply voltage; check that all pipe joints are securely connected and retighten if necessary; check that the pump head screws are tightened to the specified torque and repeat if necessary; check that all electrical connections are correct; tighten the pump head screws after the first start-up and after each diaphragm replacement; after about 6 to 10 hours of operation or after two days, tighten the pump head screws of the metering pump symmetrically with a torque wrench, maximum torque 70-80 Nm.

Start-up steps: fill with gear oil (No. 220 worm gear oil or No. 50 gear oil is recommended). The pump has been tested before leaving the factory and the oil is drained before delivery; before start-up, fill the pump with the special oil as follows: 1. Make sure the pump is switched off; 2. Loosen and remove the filler screw and the dipstick; 3. Slowly add gear oil through the filler hole until the oil level reaches the mark on the dipstick; 4. Switch on the pump; 5. After about 10 minutes, switch off the pump, check the oil level and top up if necessary; 6. Refit the filler screw and the dipstick.

Starting the metering pump: 1. Loosen the stroke locking bolt on the adjustment seat; turning the micrometer-scale stroke adjustment knob changes the flow of the pump — clockwise increases the flow and anticlockwise decreases it; the whole stroke adjustment range is marked in percent and the minimum handwheel interval is 1%; after setting the knob to the required flow, tighten the stroke locking bolt by hand to keep the set flow; 2. For pumps with a frequency converter, set the metering flow to 100%.

Oil Change and Maintenance

The first oil change is at 300–500 hours (No. 220 worm gear oil or No. 50 gear oil is recommended); to maintain the normal performance of the pump, change the gear lubricating oil every 1500 hours; this interval should be shortened when running at extreme temperatures or in dusty environments; also check the oil level in the housing regularly and irregularly, and top up with oil of the same brand and model when needed. Oil change steps: 1. Disconnect the drive motor power supply, release all pressure in the pipeline system, and close the inlet and outlet shut-off valves; 2. Unscrew the drain plug, drain all the lubricating oil in the housing, clean the dead corners of the housing to ensure they are clean and free of debris, and screw back the drain plug (check whether the sealing ring is damaged and replace it if necessary); 3. Unscrew the filler/breather plug and add new lubricating oil up to above half of the oil sight glass; 4. Screw back the filler/breather plug.

Technical Data

The range covers three sub-series: the BKS/JWM series (mechanical diaphragm): flow 5–65 L/H, pressure 1.5–10 bar, effective diaphragm diameter 65 mm, pump speed 75–150 SPM, motor 0.06 kW, inlet/outlet pipe diameter DN9; the BKS/JXM series: flow 80–2200 L/H, pressure 2–10 bar, effective diaphragm diameter 70–185 mm, pump speed 96–200 SPM, motor 0.37–1.5 kW, pipe diameter DN15–DN40; the BKS/JWZ series (plunger): flow 20–65 L/H, pressure 5–20 bar, plunger diameter 25–50 mm, strokes 96–116 min⁻¹, motor 0.25 kW, pipe diameter DN9. Protection rating IP54 for the whole range, motor 220 V/380 V. For detailed per-model data, see the user manual / selection catalogue.

Note: the rated flow and pressure are based on water-like viscosity and are subject to change without notice; customised multi-head series connection is available — heads of the same model and parameters, or of different models and parameters, can be connected in series; for the flow and pressure parameters of any single head of a multi-head metering pump, refer to the single-head metering pump parameter table.

Troubleshooting

1. The metering pump does not run
a) Power cable not connected → Connect the power cable
b) Supply voltage does not match → Replace the metering pump
c) Electrical fault → Repair
d) Diaphragm leakage detection activated → Replace the diaphragm

2. The metering pump stops drawing liquid
a) Suction line leaking → Replace or seal the suction line
b) Suction line cross-section too small or suction line too long → Improve the piping
c) Suction line blocked → Flush or replace the suction line
d) Foot valve covered by sediment → Suspend the suction line at a higher position
e) Crystal deposits in the valves → Clean the valves
f) Diaphragm ruptured or diaphragm push rod worn → Replace the diaphragm
g) Dosing tank empty → Replace the tank

3. The pump stops metering
a) Air has entered the suction line and the pump head → Wait until the pump has finished venting
b) Medium viscosity or density too high → Check whether the installation is correct
c) Crystal deposits in the valves → Clean the valves
d) Valves installed incorrectly → Install the internal components of the valves in the correct order, check and correct the liquid flow direction if possible
e) Injection point blocked → Check and correct the flow direction (injection unit) if possible, or clear the obstruction
f) Pipeline installed incorrectly or peripheral equipment installed incorrectly → Check that all pipelines are unobstructed and the equipment is installed correctly

4. The pump flow is inaccurate
a) Pump head not completely vented → Vent repeatedly
b) Degassing medium → Check whether the installation is correct
c) Valve components covered with dirt or scale → Clean the valves
d) Back pressure unstable → Install a pressure loading valve and a pulsation dampener
e) Suction lift unstable → Keep the suction level constant
f) Siphoning (inlet pressure higher than the back pressure) → Install a pressure loading valve
g) Suction or discharge line leaking or weeping → Replace the suction line or discharge line
h) Material of the wetted parts corroded by the medium → Use corrosion-resistant materials
i) Metering diaphragm aged (premature tearing) → Replace the diaphragm and observe the maintenance instructions
j) Metering medium changed (density, viscosity) → Check the medium concentration and use a stirrer if necessary

5. Excessive gear noise
a) Gear backlash too large → Contact the dealer
b) Bearing worn → Contact the dealer
c) Wrong lubricating oil grade or insufficient filling → Replace or top up the lubricating oil

6. Noise at the liquid end during operation
a) Noise in the check valves → A special "clicking" noise is normal

Warranty Terms

1. This is to certify that the product listed is covered by our company warranty and has passed strict quality control and inspection under our quality management system.
2. Please keep this certificate properly; no replacement will be issued if it is lost.
3. Failures not caused by human factors under normal use are warranted for one year from the date of purchase.
4. After the warranty period, spare parts are charged at part cost plus a service fee.
5. During the warranty period, replacement parts may be improved parts.
6. Failures caused by force majeure (such as cold weather, earthquakes, floods and other natural disasters) or by human factors are not covered by the warranty.
7. The product must be installed and used in a ventilated, dry environment with an ambient temperature not exceeding 40 °C; installation and use must be carried out by professional personnel in accordance with the instructions, and failures caused by improper installation are not covered by the warranty.
8. Please test-run and inspect the product immediately upon delivery; any quality objection must be raised within one week, otherwise it will not be accepted.