
INSTRUCTIONS for
January , 2000
R-6700 HIGH CAPACITY
PIPELINE - STATION REGULATORS
These INSTRUCTIONS are for experienced operators who are familiar with the principles of operation and safe practices in handling
gases and gas regulation equipment. If you are not sure that you understand the principles fully, your ESAB representative can supply
you with additional instructions.
SPECIFICA TIONS
Delivery Delivery Max. Capacity
Pressure Pressure for Nitrogen
Regulator Range, Gauge, ft3/hr (L/min)
psig psig "C" Size 1/2" NPT
Model Part No. (bar) (bar) Outlet Outlet
R-6701 22234 0-15 0-30 2,000 6,000
(0-1.0) (0-2.1) (945) (2830)
R-6702 22235 0-75 0-100 6,000 13,000
(0-5.2) (6.9) (2830) (6150)
R-6703 22236 0-150 0-200 10,000 13,000
(0-10.3) (0-13.8) (4720) (6150)
R-6704 2227920 0-200 0-400 12,000 13,000
(0-13.7) (0-27.6) (5680) (6150)
changed if a more convenient reading position is desired after installation.
NOTE: If regulator is to be used for supplying oxygen
or a fuel gas from a station outlet for an oxyfuel gas process, a suitable shut-off valve and
check valve (or hydraulic back-pressure valve
for fuel gas if desired) must be installed between station outlet and regulator to prevent
possible backflow. For additional information,
refer to the latest National Fire Protection
Association's Standard, NFPA No. 51.
F-15-396-B
Capacity will depend on the inlet and delivery pressures, outlet
restriction, and type of gas used (see capacity curves on pg.2).
For other gases, multiply the given nitrogen flow rate by the
following correction factors:
acetylene 1.03 hydrogen 3.68
air 0.97 methane or natural gas 1.31
argon 0.83 oxygen 0.92
carbon dioxide 0.79 propane 0.79
helium 2.61
NOTE: Piped or distributed acetylene pressure should
never exceed 15 psig (1.0 bar).
Gas Service: Any noncorrosive industrial gas.
Max. Inlet Pressure: 400 psig (27.6 bar).
Max. Inlet Pressure: 400 psig (27.6 bar).
Inlet and Outlet Connections: 1/2-in.—14 NPT fe-
male.
Operating T emp. Range:–40 to160o F; (-40 to 71o C).
Dimensions: 3-in. dia. x 6-in. (89 mm dia. x 165 mm).
Weight: 4.8 lbs. (2.2 kg)
DESCRIPTION
The R-6700 Series Regulators were designed for high
capacity service, such as multiple-torch or multi-station operators or a single equipment requiring high
gas consumption. They can be installed for either
station service or for supplying gas through a pipeline. The 1/2-in. NPT inlet and outlet female connections are "in-line" or 180o apart, as well as the 1/4-in.
NPT gauge ports. Each regulator is equipped with
the delivery pressure gauge with the other gauge port
plugged. The gauge and the pipe plug may be inter-
OPTIONAL ACCESSORIES
Shutoff Valve (V-35, P/N 998210; V-53, P/N 639674;
or V-54, P/N 998184) and CV -5 Check V alve Adaptor
(P/N 639717); A vailable to meet the latest requirements
of NFP A No. 51 when using an R-6700 regulator for station service. The V-35 and V-53 are in-line, ball-seat
type valves with 3/4-in. NPT female connections that
fully opens on 1/4 turn of the handle. The V-35 has
replaceable seat seals. The V -54 is a 90
o
throttle type
valve with 3/4-in. NPT male inlet and female outlet. The
CV-5 is a 3/4-in. NPT male x 1/2-in. NPT male adaptor
with a built-in check valve for coupling any of the shutoff
valves to an R-6700 regulator.
Hose Outlet Adaptor: The following 1/2-in. NPT male
x "C"-size adaptors are available for connecting "C"size hose from outlet of regulator to the gas using equipment:
Oxygen "C" ................ (7/8 - 14 male R.H.)P/N 18Z55
Fuel Gas "C"...............(7/8 - 14 male L.H.)P/N 18Z08
Inert Gas "C"......... (7/8 - 14 female R.H.)P/N 639377
INST ALLATION
Since the regulators are provided with pipe con-
nections for direct attachment to any pipeline, a
responsible person must determine that a regulator is installed in the correct, properly labeled pipeline. Also a regulator must not be changed from
one gas service to another until a responsible person has determined that it is safe to do so.
Be sure this information reaches the operator.
Y ou can get extra copies through your supplier.

Make sure all gas carrying piping and apparatus is
free of oil and grease before installing the regulator, particularly when using oxygen. OIL AND
GREASE ARE EASILY IGNITED AND BURN VIOLENTLY IN THE PRESENCE OF OXYGEN UNDER
PRESSURE.
Apply a single turn of T eflon t ape to the male pipe
threads before making the pipe connections.
Tighten all connections firmly with a wrench. Ref.:
MIL-T-27730A (ASG).
For Station Service:
1. Install the V -35. V-53, or V -54 shut-off valve to st ation outlet. (If station outlet is other than 3/4-in.
pipe use suitable adaptors, bushings, etc.) and then
the 3/4-in. NPT end of the CV -5 check valve to the
shut-off valve.
2. Close the shut-off valve and turn on the gas supply .
3. Open the shut-off valve slightly , for an instant. (This
is termed as 'cracking the valve'.) This will blow out
dust or dirt that may have collected in the station
outlet.
Never crack a fuel gas valve near sparks,
flames, or any other possible source of ignition.
2. When making the initial delivery pressure adjustment, all valves downstream of the regulator must
be open if you wish to get a true working-pressure
reading on the delivery-pressure gauge.
IMPORTANT: Before starting operations, test all con-
nections with a Leak Test Solution that
is suitable for oxygen service, such as
P/N 998771 (8 oz. container). Correct
any leaks before starting work. T esting
should be performed after torch or other
gas using device a has been properly
connected, with valve(s) downstream of
regulator closed, and with maximum delivery pressure (see table) in the delivery
line.
T o Release Pressure:
If operations are to be stopped for a half-hour or more,
you should release all pressure from regulator. To do
this, proceed as follows:
1. Close the station valve.
2. Open all valves downstream of the regulator.
3. Wait until the pressure has dropped to zero, then
back out the pressure-adjusting screw until it turns
freely .
4. Connect the inlet of the regulator directly to the
check valve.
5. MAKE SURE the regulator pressure adjusting screw
is released by turning it counterclockwise until it
turns freely .
6. Connect hose adaptor to the outlet of the regulator
then attach hose from outlet to the gas using equipment.
7. Open the shut-off valve SLOWL Y and the regulator
is ready to operate.
Never stand in front of or behind the regulator
when opening the valve. Always stand to one
side.
For Pipeline Service:
If regulator is to be used for supplying gas to a pipeline,
it is not necessary to install a shut-off valve and check
valve upstream of regulator. Follow the same sequence
as described for station service installation where appropriate. Make sure "IN" connection of the regulator is
installed on the gas supply line and the delivery line is
connected to the "OUT" connection.
OPERA TION
T o Adjust Pressure:
1. To increase delivery pressure, turn the pressureadjusting screw clockwise. To decrease delivery
pressure, turn the pressure adjusting screw counterclockwise.
NOTE: If a regulator is to be out of use for few days or
more, turn in the pressure-adjusting screw
enough to move the valve stem off the seat.
When the regulator is returned to use, be sure
to back off the pressure-adjusting screw until it
turns freely before pressure is admitted to the
regulator.
REP AIR SERVICE
Regulators in need of repair should be returned to your
ESAB distributor or to ESAB Remanufacturing Center,
41 1 S. Ebenezer Road, Florence, SC 29501.
MAX. DELIVERY PRESS.
R-6704
MAX. DELIVERY PRESS.
MAX. DELIVERY PRESS.
DELIVERY PRESSURE, PSIG
100 PSIG
50 PSIG
INLET
Capacity Curves - R-6700 Series regulators
R-6703
200 PSIG
INLET
R-6702
INLET
MAX DELIVERY PRESS.
R-6701
NITROGEN FLOW RATE, CU. FT./HR.
300 PSIG
INLET
“C” SIZE OUTLET (0.328 I.D.)
1/2" NPT. SCH. 40 OUTLET (0.622" ID.)
400 PSIG
INLET
F-15-396-B 1/2000 2M Printed in U.S.A.