Air diaphragm pump that uses a combination of the reciprocating
action of a rubber,thermoplastic or teflondiaphragm and suitable
valves either side of the diaphragm (check valve,butterfly
valves,flap valves,or any other form of shut-off valves) to pump a
- Place of Origin:China
- Brand Name:BSK
- Model Number: BSKA25AL-P99-A
- Min. Order Quantity: 10 Unit(s)
- Price Term: FOB
- Port: Guangzhou/Shenzhen
- Price: Negotiable
- Payment Terms:T/T
- Production Capacity: 1000 Unit(s) Per Month
- Guarantee: one year
Air Diaphragm Pump
1. Non leakage
2. Good self priming performance
3. Convey all kinds of medium
4. Material:Cast steel,Alu,SS,PP
A 06 X X - X X X - X (model selection)
Form of pipe mouth:A-BSP B-NPT(F) C-Flange
Diaphragm material:9 – Santoprene H – Hytrel T - PTFE/Santoprene
Ball material:9 -Santoprene H – Hytre T – PTFE A - Acetal
Ball seat material:P/K –Polypropylene/Kynoar SS –Stainless Steel
Pump material: SS –Stainless Steel AL –Aluminum Alloy CI- Carbon
Steel P/K –Polypropylene/Kynoar
Main Performance Parameters
No. Parameter Names Units Reference Values
1 Max. Working Air Pressure Mpa 0.83
2 Max. Flow l/min 135
3 Max. Head m 70
4 Max. Fluid Output Pressure Mpa 0.83
5 Max. Particle Through Diameter mm 3
6 Weight kg 9.5/12.5 ( PP/KV ) /9.5 (AL)/ 14.5(SS/CI)
7 Noise Level db <85
Maximum Applied Temperature Limits (diaphragm / ball / seal material)
Acetal ···············································40°- 150°F
225°F (-40°- 107.2°C)
220°F (4.4°- 104°C)
180°F (-12°- 82°C)
0.25” Flow diagram
The BSK diaphragm pump offers high volume delivery even at low air
pressure and a b road range of material compatibility options
available.Refer to the model and option chart.The BSK pump is
provided with the modularized air motor and fluid section.
The air operated diaphragm pump alternately generates the intake
fluid pressure and positive fluid pressure in the fluid chamber by
using the pressure difference in the air chamber. The ball valve
can ensure the forward flow of fluid.
Pump cycling will begin as air pressure is applied and it will
continue to pump and keep up with the demand. It will build and
maintain line pres -sure and will stop cycling once maximum line
pressure is reached (dis -pensing device closed) and will resume
pumping as needed.
Requirements for Air and Lubrication
EXCESSIVE AIR PRESSURE. Can cause pump damage, personal injury or
- A filter capable of filtering out particles larger than 50 microns
should be used on the air supply. There is no lubrication required
other than the “O” ring lubricant which is applied during assembly
- If lubricated air is present, make sure that it is compatible with
the “O” rings and seals in the air motor section of the pump.
- Always flush the pump with a solvent compatible with the material
being pumped if the material being pumped is subject to “setting
up” when not in use for a period of time.
- Disconnect the air supply from the pump if it is to be inactive for
a few hours.
- The outlet material volume is governed not only by the air supply
but also by the material supply available at the inlet. The
material supply tubing should not be too small or restrictive. Be
sure not to use hose which might collapse.
- When the diaphragm pump is used in a forced -feed (flooded inlet)
situation, it is recommended that a “Check Valve” be installed at
the air inlet.
- Secure the diaphragm pump legs to a suitable surface to insure
against damage by vibration.
- Please refer to the component schematic in the assembly drawings to
look up the serial numbers and names of parts and grasp the
information of parts and maintenance service pack.
- Some BSK parts are marked as "wearing parts", which can conduce to
quick service and downtime reduction.
- Service kits are divided to service two separate diaphragm pump
functions: 1. AIR SECTION, 2. FLUID SECTION. The FLUID SEC -TION is
divided further to match typical part MATERIAL OPTIONS.
- Provide a clean work surface to protect sensitive internal moving
parts from contamination from dirt and foreign matter during
service disassembly and reassembly.
- Keep good records of service activity and include pump in preven
-tive maintenance program.
- Before disassembling, empty captured material in the outlet man
-ifold by turning the pump upside down to drain material from the
FLUID SECTION DISASSEMBLY
- Remove the upper and lower manifold (1) and (11).
- Remove the ball (2), “O” ring (3) (47) and ball seat (4).
- Remove the fluid cap (5).
NOTE: Only diaphragm models use a primary diaphragm(6A) and a
backup diaphragm(6). Refer to the aux iliary view in the Fluid
- Remove the screw (10), washer (9), diaphragm (6A, 6) and diaphragm
washer (7, 8).
NOTE: Do not scratch or mar the surface of (23) diaphragm rod.
FLUID SECTION REASSEMBLY
- Reassemble in reverse order.
- Clean and inspect all parts. Replace worn or damaged parts with new
parts as required.
- Lubricate (23) diaphragm rod and 25) “Y” ring with grease.
- Fix the diaphragm rod (23) with the auxiliary installation tool.
- Prior to the final fastening of bolts and nuts, please determine
whether the diaphragm (6A,6) is aligned with the fluid cap (5)
properly to avoid the twisting of the diaphragm.
- For the models using Teflon diaphragm: three rubber diaphragms (6)
on the side, which are marked with AIRS SIDE "air chamber" are
mounted in face of the pump body.
- Start the pump, check the fastening and sealing after it runs for a
period of time.
Disassembly of the Parts in Fluid Section
a)First, remove the pump from the pipeline system and drain off the
materials from the pump inside. b)Place the pump in a clean work
environment. c)Dismantle the outlet pipe (1) from the pump first,
and then take out the ball (2), O cup (3) and (47) and ball seat
(4) from the upper end of the fluid cap (5) in sequence. After
that, place the pump upside down and dismantle the inlet pipe (11)
so as to take out O cup (3) and (47), ball seat (4) and ball (2)
from the fluid cap (5). d)Release the bolts around the two fluid
caps to disassemble the cap (5). e)Release the diaphragm screw (10)
and remove diaphragm washer (7), (8) and diaphragm (6) from the
both ends. Remove the diaphragm rod (23) and the lip-shape seal
ring (25) can be replaced. Disassembly of Parts for Air Valve
f)Loosen the bolt (39) first, and then dismantle the air valve
casing (38), air baffle (42) and sealing gasket (40), and (41). g)
Take out the valve slice (36) and valve plate (37) from the air
valve casing (38). h) Dismantle the circlip (29) and take out the
limit end cap (31) from both ends of the air valve casing (38), and
you can replace the cup (30) as needed. i)You can check the
lip-type packing (33) after pushing out the spool (35) from the air
valve casing (38) with the hands. Disassembly of Parts for Pilot
Valve j) Loosen 4 bolts (16) fixing the cylinder head first, and
then dismantle the cylinder head (14) and (18) on both ends and
remove the O cup (17). k) Remove the sealing gasket (19) from the
groove of the motor casing (15). l) Eject the pilot rod (22) and
trigger rod (45) from the motor casing (15) and you can replace the
lip-type packing (20) on the trigger rod or the O cup (44) on the
pilot rod. Reassembly of Diaphragm Pump The reassembly steps of the
pump are incompatible with those of disassembly, so you are kindly
asked to pay attention to the following in the reassembly process:
1) All the sealing elements, as well as their contact parts, must
be greased. 2) Please check carefully prior to the use of all
sealing elements whether they are damaged, such as surface damage.
If damaged, please replace the new ones. 3) The lip direction of
the lip-type packing (20)(, 25) and (33) should be consistent with
the direction shown in the chart. 4) The bolts on the fluid cap
should alternately be fastened by opposite angles to achieve a
better sealing result. Troubleshooting 1. Some fluid is drained
from the exhaust opening along with the air flow. Check the
diaphragm for any damage. Check the diaphragm screw for looseness
2. There are Air bubbles in the outlet fluid Check the suction pipe
connection for good sealing. Check the connection between the
suction pipe and the intake manifold for good sealing. Check the O
ring between the intake manifold and the fluid cap Check the
diaphragm screws for looseness 3. Low pump output Check the air
supply is stable. Check the inlet/outlet for any blockage. Check
connectors connecting the intake manifold for air tightness Check
that the ball is not stuck to the seat or the ball is not
improperly seated. 4. Air is discharged from the exhaust opening
when there is no reciprocating movement. Check seal ring (33) on
slid valve (35). Check seal ring (20) on trigger rod (45). Check
seal ring (25) on diaphragm link rod