Kofloc 6800 User manual

FJ400051D1
Created on 2021/12/20
- 1 -
Back Pressure Regulating Valve Model 6800
Large - flow back Pressure Regulating Valve Model 6801
Instruction Manual
Thank you for your selection of “KOFLOC Back Pressure Regulating Valve.”
Prior to use, read this manual thoroughly to ensure your new meter will work to its
fullest capacity.

FJ400051D1
Created on 2021/12/20
- 2 -
CAUTION
This is a relief valve designed to keep the pressure on the
primary side of the valve constant and may be used for
pressure up to:
Maximum working pressure: 0.8 MPa(G)
The use of fluids, such as toxic gas, other than those marked
on the flow meter or the use of the product at a temperature
or pressure above the maximum limits could result in
personal injury. Such a way of use is strictly prohibited.
Foreword
Thank you for your selection of Model 6800/Model 6801.
Prior to using your pressure regulating valve, please read this manual thoroughly to
ensure the valve will operate to its maximum performance.
・The contents of the manual are subject to change without prior notice.
・The manual has been carefully created and checked before shipment. If you notice
any deficiencies, errors or omissions, however, please inform us.
・The warranty period of the pressure regulating valve is one (1) year from the date of
shipment from our plant.
・Any failures which may occur during this period and are attributable to our
workmanship will be corrected free of charge.
・KOFLOC shall bear no responsibility whatsoever for breakage or troubles of
equipment resulting from neglect of the precautions presented in this manual or use
of the pressure regulating valve in manners not described herein.

FJ400051D1
Created on 2021/12/20
- 3 -
■Model 6800
1) Features
Panel-mount type for easy installation.
Small and compact design capable of high-speed control of the primary side pressure.
This is a greaseless clean valve for pure gas control.
2) Installation and Piping
①Prior to connecting a pipe to the valve, be sure to flush the pipe. Dust/dirt, sand,
scale, etc. remaining inside the pipe are causes of malfunction and failure.
②When processing piping materials for connection, exercise extreme care. Sealing
material, produced chips, etc. remaining inside the pipe are causes of malfunction
and failure. When applying sealing material to the pipe, be sure that it will not
cover the first one turn of threads.
③The IN marking indicates the inlet of fluid and the OUT marking the outlet. If the
valve is installed in a wrong direction, it will not operate properly.
3) Set pressure adjusting method
①From low pressure to high pressure: While checking the line pressure gage, turn the
adjust knob of the back pressure control valve clockwise to set a desired pressure.
②From high pressure to low pressure: Turn the adjust knob counterclockwise to lower
the pressure below the set pressure, and then turn the adjust knob clockwise to set a
desired pressure.
4) Other precautions
①Use this back pressure control valve within the specified range.
②Prior to introducing gas, turn the adjust knob of the pressure reducing valve
counterclockwise to keep it loosened fully. Then introduce gas.

FJ400051D1
Created on 2021/12/20
- 4 -
●Specifications
Type
6800A
6800B
6800AL
6800BL
Secondary side control
pressure
0.01‐
0.3MPa(G)
0.01‐
0.6 MPa(G)
0.01‐
0.3 MPa(G)
0.01‐
0.6 MPa(G)
Max.exhaust flow
1 L/min
0.8 L/min
10 L/min
10 L/min
Pressure resistance
0.8MPa(G)
Materials or areas in
contact with fluid
(A) Al, Brass, NBR, SUS316
(SS) SUS316, FKM, SUS303
Environmental temp.
5℃‐60℃
Connecting port
Rc1/4(Standard), Rc1/8(Optional)
●Construction and External Dimensions
1/ Body
2/ Diaphragm
3/ Bonnet
4/ Bonnet bearing
5/ Pressure regulating shaft
6/ Mounting nut
7/ Cap nut
8/ Knob
9/ Adapter
10/ Gauge port plug
MODEL
A
B
C
D
E
F
G
H
6800A
28
30.5
25
11
IN
OUT
10
37
6800B
31
30.5
30
11
IN
OUT
13
40
6800AL
28
34.5
25
14
OUT
IN
10
37
6800BL
31
34.5
30
14
OUT
IN
13
40
(mm)

FJ400051D1
Created on 2021/12/20
- 5 -
■Model 6801
1) Features
Panel-mount type for easy installation.
Capable of high-speed control of the primary side pressure. This is a greaseless
clean valve for pure gas control.
2) Installation and Piping
①Prior to connecting a pipe to the valve, be sure to flush the pipe. Dust/dirt, sand,
scale, etc. remaining inside the pipe are causes of malfunction and failure.
②When processing piping materials for connection, exercise extreme care. Sealing
material, produced chips, etc. remaining inside the pipe are causes of malfunction
and failure. When applying sealing material to the pipe, be sure that it will not
cover the first one turn of threads.
③The IN marking indicates the inlet of fluid and the OUT marking the outlet. If the
valve is installed in a wrong direction, it will not operate properly.
3) Set pressure adjusting method
①From low pressure to high pressure: While checking the line pressure gage, turn the
adjust knob of the back pressure control valve clockwise to set a desired pressure.
②From high pressure to low pressure: Turn the adjust knob counterclockwise to lower
the pressure below the set pressure, and then turn the adjust knob clockwise to set a
desired pressure.
4) Other precautions
①Use this back pressure control valve within the specified range.
②Prior to introducing gas, turn the adjust knob of the pressure reducing valve
counterclockwise to keep it loosened fully. Then introduce gas.

FJ400051D1
Created on 2021/12/20
- 6 -
●Specifications
Type
6801A
6801B
Secondary side control pressure
0‐0.3MPa(G)
0‐0.6MPa(G)
Max.exhaust flow
300L/min
Pressure resistance
0.8MPa(G)
Repeatability
Within ±1% of rated pressure
Environmental temp.
5℃‐60℃
Materials or areas in contact with fluid
SUS303, FKM, PTFE
Connecting port
Rc1/2
●Construction and External Dimensions
1/ Main unit
2/ Bonnet
3/ Diaphragm
4/ Mounting nut
5/ Bonnet bearing
6/ Cap nut
7/ Pressure regulating shaft
8/ Knob

FJ400051D1
Created on 2021/12/20
- 7 -
●Troubleshooting (Model 6800)
Trouble
Cause
Corrective Action
The pressure
cannot be
adjusted.
1. The direction of flow is
reversed or the valve
installation is reversed.
2. The pressure regulating
spring has been broken.
3. The nozzle spring has been
broken.
4. Dust is sticking to the nozzle
O-ring.
5. The nozzle O-ring has been
damaged.
1. Check the direction of flow.
If it is reversed, reinstall the
valve correctly.
2. Please return it to us.
We’ll check it and repair it.
3. Please return it to us.
We’ll check it and repair it.
4. Please return it to us.
We’ll check it and repair it.
5. Please return it to us.
We’ll check it and repair it.
The set pressure
will not become
zero when the
pressure
regulating
handle is
loosened.
1. Dust is sticking to the nozzle
O-ring.
2. The nozzle O-ring has been
damaged.
3. The nozzle spring has been
broken.
1. Please return it to us.
We’ll check it and repair it.
2. Please return it to us.
We’ll check it and repair it.
3. Please return it to us.
We’ll check it and repair it.
Gas is leaking
from the small
hole of the
bonnet.
1. The diaphragm has been torn.
1. Please return it to us.
We’ll check it and repair it.
Gas is leaking
from around the
bonnet.
1. The bonnet is loose.
2. The diaphragm has been torn.
1. Retighten the bonnet.
2. Please return it to us.
We’ll check it and repair it.

FJ400051D1
Created on 2021/12/20
- 8 -
●Troubleshooting (Model 6801)
Trouble
Cause
Corrective Action
The pressure
cannot be
adjusted.
1. The direction of flow is
reversed or the valve
installation is reversed.
2. The pressure regulating
spring has been broken.
3. The valve spring has been
broken.
4. Dust is sticking to the valve
O-ring.
5. The valve O-ring has been
damaged.
1. Check the direction of flow.
If it is reversed, reinstall the
valve correctly.
2. Please return it to us.
We’ll check it and repair it.
3. Please return it to us.
We’ll check it and repair it.
4. Please return it to us.
We’ll check it and repair it.
5. Please return it to us.
We’ll check it and repair it.
The set pressure
will not become
zero when the
pressure
regulating
handle is
loosened.
1. Dust is sticking to the valve
O-ring.
2. The valve O-ring has been
damaged.
3. The valve spring has been
broken.
1. Please return it to us.
We’ll check it and repair it.
2. Please return it to us.
We’ll check it and repair it.
3. Please return it to us.
We’ll check it and repair it.
Gas is leaking
from the small
hole of the
bonnet.
1. The diaphragm has been torn.
1. Please return it to us.
We’ll check it and repair it.
Gas is leaking
from around the
bonnet.
1. The bonnet is loose.
2. The diaphragm has been torn.
1. Retighten the bonnet.
2. Please return it to us.
We’ll check it and repair it.

FJ400051D1
Created on 2021/12/20
- 9 -
●Product Warranty Policy
Thank you for your continued support of KOFLOC products.
Unless specified otherwise in quotations, contracts or specifications when you place
orders for KOFLOC products, the following warranty policy will apply.
Warranty Policy:
①Warranty period
The warranty period is one (1) year from shipment, provided that the product is
used within the KOFLOC specification.
②Scope of warranty
If the KOFLOC product fails during the warranty period due to a cause
attributable to KOFLOC, KOFLOC shall, at its option and expense, provide a
replacement product or repair the failed product at the KOFLOC factory.
This warranty, however, shall not cover damages due to a cause not
attributable to KOFLOC; opportunity loss, lost profit, secondary disaster,
accident compensation suffered by the customer and damage to other
equipment and any other damages due to a failure of the KOFLOC product.
③Non-warranty
The warranty shall not apply to the following failures and damages even if they
occur during the warranty period:
a) Failure due to misuse or improper repair or modification. (Failures
resulting from use under conditions different from the manufacturing
specifications are included.)
b) Damage and failure due to dropping of the product after purchase.
c) Failure due to fire, earthquake, flood, lightning or other natural disaster; or
riot, war or the like.
d) Failure due to intrusion of foreign matter from piping.
e) Failure caused by a specific problem due to combination with other
incorporated equipment.
f) Other failures and damages which are considered not attributable to
KOFLOC.
Please be aware that the warranty shall not cover opportunity loss suffered
by you or your customer or damage to other equipment or any other damages
due to a failure of the KOFLOC product.
URL：http://www.kofloc.co.jp