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Permanent Gauging Blocks
Installation Instructions
DESCRIPTION
The HYDAC Permanent Gauging
Block is designed to fit the
following types of HYDAC
accumulators: bladder, diaphragm
(with HYDAC gas valve version 4,)
and piston (with HYDAC gas valve
version 4.)
GENERAL
WARNING!
Before performing any maintenance
always relieve the gas and fluid
pressures completely from the
accumulator. Hydraulic
accumulators are pressurized
vessels and only qualified
technicians should perform repairs.
Never weld, braze or perform any
type of mechanical work on the
accumulator cylinder.
SPECIAL TOOLS REQUIRED
1) Charging and Gauging Unit
(1
2) Gas Valve Core Tool
3) 50 mm Open End Wrench (for
bottom repairable accumulator)
4) 32 mm Open End Wrench (for
top repairable accumulator)
5) Torque Wrench(es)
Currently the HYDAC Permanent
Gauging Block is only available for
use with HYDAC gas valve version 4.
Read all instructions thoroughly
before beginning any type of
service or repair work.
Refer to additional information
contained in the "Operating and
Installation Instructions for HYDAC
Accumulators."
1) for HYDAC gas valve version 4
use either the FPS Charging and
Gauging Unit or the FPK Charging
and Gauging Unit with adapter
FPK/SB.
!!
CAUTION
GAS CHARGING
PRESSURIZED VESSEL -
USE DRY NITROGEN GAS ONLY!
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1.DISASSEMBLY
A) Relieve the fluid side pressure
completely from the accumulator.
Unscrew valve protection cap
(item 6 if applicable) and valve
seal cap (item 5).
For bottom repairable bladder
accumulators with 7/8"-14 UNF
gas valve proceed to step 1.B.
For top repairable bladder,
bottom repairable bladder with
M50x1.5 gas valve, diaphragm,
and piston type accumulators
proceed to step 1.C.
B) Insure there is a minimum of 150
PSI gas precharge pressure in
the accumulator by attaching the
proper HYDAC Charging and
Gauging Unit (refer to HYDAC
Charging and Gauging Unit
brochure #02071833). If the gas
precharge pressure is too low,
increase it to 150 PSI. Once the
gas precharge pressure is set
remove the Charging and
Gauging Unit from the gas valve.
Remove and discard lock nut
(item 4) and replace it with the
new low profile lock nut (item 4)
furnished with the permanent
gauging block. Torque the new
low profile lock nut. Proceed to
step 1.C.
C) Attach the proper HYDAC
Charging and Gauging Unit and
completely relieve the gas
precharge pressure. Refer to
HYDAC Charging and Gauging
brochure #02071833.
D) After the gas precharge pressure
is completely relieved, remove
the Charging and Gauging Unit
from the gas valve.
E) Remove and discard the gas
valve core (item 3) and o-ring
(item 7) from the gas valve. Be
sure to use a gas valve core tool
to remove the gas valve core.
The use of any other implement
may damage the internal threads
of the gas valve, thus the bladder
or complete accumulator may
have to be replaced.
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2.ASSEMBLY
A) Before attaching the HYDAC
Permanent Gauging Block, be
certain the o-ring (11x 2) in the base
of the block is properly seated.
For diaphragm, piston, bottom
repairable bladder with M50 gas
valve, and top repairable bladder
accumulators proceed to step 2.B.
For bottom repairable bladder
accumulator with 7/8"-14 UNF
gas valve proceed to step 2.C.
B) For top repairable bladder
accumulators, first screw on the
modified valve protection cap
(item 6A). Screw the Permanent
Gauging Block onto the
accumulator gas valve (use a 32
mm Open End Wrench), and
torque to 50 Newton Meters (37
foot pounds). Proceed to step
2.D.
C) Screw the Permanent Gauging
Block onto the accumulator gas
valve, hand tighten only. Use a
50 mm open end wrench or
equivalent (for top repairable
accumulators use a 32 mm Open
End Wrench), turn the Permanent
Gauging Block just until it is
tight. DO NOT OVER TIGHTEN. If
the Permanent Gauging Block is
over tightened at this stage of
installation the bladder may twist
in the shell and fail.
Attach appropriate HYDAC
Charging and Gauging Unit (refer
to HYDAC Charging and Gauging
Brochure #02071833). Apply dry
nitrogen gas charge of 150 PSI
to the accumulator. This will
secure the bladder and prevent it
from twisting in the shell when
tightening the Permanent
Gauging Block. Remove the
HYDAC Charging and Gauging
Unit. Torque the Permanent
Gauging Block to 50 Newton
Meters (37 foot pounds).
D) Attach appropriate HYDAC
Charging and Gauging Unit (refer
to HYDAC Charging and Gauging
Unit Brochure #02071833) and
apply proper gas precharge
pressure. Remove HYDAC
Charging and Gauging Unit.
E) Screw on the valve seal cap
(item 5), torque to 30 Newton
Meters (22 foot pounds).
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Bottom Repairable Bladder Accumulators
HYDAC Gas Valve Version 4 - Assembly View
Permanent Gauging Block - Assembly View
Item Description
3 Gas Valve Core
4 Lock Nut
5 Valve Seal Cap
6 Valve Protection Cap
7 O-RING (7.5 x 2)
8 Name Plate
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Top Repairable Bladder Accumulators
HYDAC Gas Valve Version 4 - Assembly View
Permanent Gauging Block - Assembly View
Item Description
3 Gas Valve Core
4 Lock Nut
5 Valve Seal Cap
6 Valve Protection Cap
6A Valve Protection Cap (modified)
7 Name Plate
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Diaphragm and Piston Accumulators
HYDAC Gas Valve Version 4 - Assembly View
Permanent Gauging Block - Assembly View
Item Description
3 Gas Valve Core
5 Valve Seal Cap
7 O-RING (7.5 x 2)
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Bottom Repairable Bladder Accumulators with M50 Gas Valve
HYDAC Gas Valve Version 4 - Assembly View
Permanent Gauging Block - Assembly View
Item Description
3 Gas Valve Core
4 Lock Nut
5 Valve Seal Cap
6 Valve Protection Cap
7 O-RING (7.5 x 2)
8 Name Plate
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© Copyright 1999 HYDAC TECHNOLOGY CORPORATION - Brochure - SAB Safety & Shut-off Blocks - #02072836 / 08.00
HYDAC
CORPORATION
2280 City Line Road • Bethlehem, PA 18017
Phone (610) 266-0100 • Fax (610) 264-7529
www.hydacusa.com • powerup@hydacusa.com
Other Products from HYDAC’s Accumulator Line
Diaphragm Accumulators
Diaphragm accumulators are frequently used where small volumes are
required, light weight is important, a higher pressure ratio is required
(up to
10:1)
, and low cost is a prime factor. Two styles are available weld (non-
repairable)
and threaded (repairable). Both are suited for energy storage and
shock applications.
Nominal volume: 5 in3to 1 gal.
Max. working pressure: 3000, 4700, and up to 10,000 psi
Flow rate: up to 40 gpm
Piston Accumulators
A wide range of piston accumulators is available. Piston position monitoring is
available using proximity switches, extending piston rod or ultrasonic
techniques. Auxiliary gas bottles are frequently used with piston accumulators
to provide the required gas volume.
Nominal volume: 1 qt. to 100 gal.
Max. working pressure: 3000, 5000, and up to 15000 psi
Flow Rate: up to 2000 gpm
Charging & Gauging
To maintain system performance, HYDAC recommends a regular check of the
gas precharge pressure. A loss in the gas precharge pressure will cause a
drop in the system efficiency and could cause damage to the bladder,
diaphragm or piston accumulator. By means of a charging and gauging unit,
hydro-pneumatics accumulators are precharged with dry nitrogen or their
existing gas precharge pressure is checked. For these purposes, a charging
and gauging unit is connected to a commercially available nitrogen bottle via
a flexible hose. The charging and gauging units incorporate a gauge, check
valve in the charging connection, manual bleed valve and T-handle.
Request catalog # 02071832
Request catalog # 02071831
Request catalog # 02068597
Request catalog # 02071833
Bladder Accumulators
The bladder style accumulator is a great general purpose accumulator. It has
a wide range of sizes for energy storage requirements and is well suited for
shock applications.
Nominal volume: 1 qt. to 15 gal.
Max. working pressure: 3000, 5000 and up to 15000 psi
Flow rate: up to 480 gpm
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