ERHARD NON SLAM Operating Instructions Manual

BA43E000

Operating Instructions

ERHARD NON SLAM

Nozzle Check Valve

ERHARD NON SLAM
Nozzle Check Valve

ERHARD NON SLAM
Nozzle Check Valve (option)

You are requested to follow operating
instructions BA43D001.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 1 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Index of contents

These operating instructions must always be used in combination with operating
instructions BA01E001!

1. Description of product and performance 3

1.1 ERHARD NON SLAM Nozzle Check Valves 5
DN 80 - 600, PN 10 – PN 40 prod. No. 435...00

1.2 Design Features – Technical Data 5

1.2.1 ERHARD NON SLAM Nozzle Check Valves
DN 80 – 300 1.2.2 5

1.2.2 ERHARD NON SLAM Nozzle Check Valves
DN 350 – 600 7

1.3 Performance and mode of operation 8

1.4 Application according to the rules 9

1.5 Transport and storage 9

1.5.1 Transport 9

1.5.2 Storage 10

1.6 Installation into the pipeline 10

2. Maintenance 14

2.1 Maintenance 15

2.2 Spare parts 15

2.3 Replacement of spare parts / necessary devices 16

2.4 Trouble during operation and remedies 18

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 2 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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1 Description of Product and Performance

ERHARD NON SLAM Nozzle Check Valves (EDRV)
DN 80 – 600, PN10 – PN40 Product No. 435...00

The ERHARD NON SLAM Nozzle Check Valve is a non-return valve of compact design
and short pattern, with central rubber-coated valve disc (DN 80-300) or valve ring (DN
350-600) which opens and closes in axial direction, the closing movement being spring­assisted.
Thanks to the materials and the sealing and corrosion protection systems, the
ERHARD NON SLAM Nozzle Check Valve is suitable for application in the water
industry (mechanically neutral water up to a max. temperature of 60° C) and for pre­treated sewage.
In case of hot flow media, there is the risk of burns and the valve has to be heat­insulated by the user.

The normal range of flow velocity of the ERHARD NON SLAM Nozzle Check Valve is
0,5 – 5 m/s (referred to the nominal size DN). At a velocity of 2 m/s (referred to DN) the
ERHARD NON SLAM Nozzle Check Valve is used in a fully economical way. With
these velocities, all nominal sizes are in fully open position.

For opening the ERHARD NON SLAM Nozzle Check Valve , according to DN, 0,5 – 0,9
mWC (50 – 90 mbar) as minimum differential pressure is necessary. The valve opens at
this differential pressure and the medium begins to flow. For tight closure, a minimum
back pressure of approx. 4.0 mWC (400 mbar) is necessary for DN 80 – 300 and of
approx. 8 mWC (800 mbar) for DN 350 – 600.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 3 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

]

r

p

Pressures:

Nominal size

DN [bar] [bar] [bar]

PN PFA PMA PEA

Hydr. test pressure [bar

fo

body seat

80 - 300

10 10 12 17 15 10

350 - 600

80 - 300

24 1616 16 20 25

350 - 600

80 - 300 25 25 30 35 37,5 25
80 - 300 40 40 48 56 60 40

The ERHARD NON SLAM Nozzle Check Valves are tested at the manufacturers' works
for strength and tightness according to DIN EN 12266 / 1074.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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1.2 Design Features – Technical Data

1.2.1 ERHARD NON SLAM Nozzle Check Valve DN 80 – 300

Fig. 1.1
Dimensions of ERHARD NON SLAM Nozzle Check Valve DN 80 – 300:

PN10 PN16

DN

Døk d4b

80

200 160 132 200 160 132 200 160 19 132 200 160 19 132 3 180

100

220 180 156 220 180 156 235 190 23 156 235 190 23 156 3 190

125

250 210 184 250 210 184 270 220 184 23,5 270 220 184 23,5 3 200

150

285 240 211 285 240 211 300 250 211 26 300 250 211 26 3 210 -

200

340 295 266 20 340 295 266 20 360 310 274 22 375 320 31 284 30 3 230 -

250

400 350 319 22 400 355 319 22 425 370 330 24,5 450 385 345 34,5 3 250 -

300

455 400 370 24,5 455 410 370 24,5 485 430 16 389

d2 d2 d2 d2

d4 b D øk D øk D økd4 b

øz øz øz øz

19

23

12

8

19

19

819

23

12

28

PN25

28

31

12

PN40

19

8

28

515 450 16 409 39,5 4 270 20

27,5

34

*Attention: For nominal size DN 300 the guiding stem protrudes by 20 mm

when the valve disc is open!

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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d4 b L l*

19

8

12

Page 5 of 18

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Parts list for ERHARD NON SLAM Nozzle Check Valves DN 80 – 300
with standard materials

Description Qty. Notes

Item

Body 80-125

Body 150 - 300 EN-JS1030 EN-JS1025
2 Internal body 1 zinc-free bronze
3 Threaded pin 3 stainless steel
4Bush 2

5,8,9 Valve disc 1

6 Guiding stem 1 stainless steel
7 Pressure spring 1

Mate ri al / Sta nd ar d

PN 10/16 PN25/40
EN -JS1025

2.1050.01
A4
High-performance polymer

2.1050.01/NBR or

2.1050.01/EPDM

1.4057.05

1.4310

ductile cast iron11

vulcanized NBR or EPDM
rubber-coating

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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1.2.2 ERHARD NON SLAM Nozzle Check Valves DN 350 – 600

Fig. 1.2
Dimensions of ERHARD NON SLAM Nozzle Check Valve DN 350 – 600:

PN10 PN16

DN

Døk d4 b

505 460 23 429 26,5 520 470 28 429 26,5 290 8

350

565 515 480 28 580 525 31 480 28 310 10

400

670 620 582 31,5 715 650 34 609 31,5 350 15

500

780 725 31 682 30 840 770 37 720 36 5 390 9

600

d2 d2

øz øz

16

28

20

bDøk

d4 L l*

16

20

f

4

*Attention: DN 350 – 600: the guiding stems protrude over the face-to-face dimension when the valve ring
is open!

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 7 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Parts list for ERHARD NON SLAM Nozzle Check Valves DN 350 – 600

with standard materials

Item Description Qty. Material Notes

Body 350 - 400 EN-JS1030

Body 500 - 600 EN-JS1025

2 In ternal body 1 2.1050.01 zinc-fr ee bronze
3 Threaded pin 4 A4 stainless steel
4 Bush 8 High-performance polymer

5 Piston ring 1 1.4404/EPDM
6 Guide rod 4 1.4057.05 stainless s teel

7 Pressure spring 4 1.4310.07 s tainless steel
8 Threaded bush 4 A4 stainless steel
9 Washer 4 NBR or EPDM

10 Cover 1 2.1050.01 zinc-free bronze

ductile cast iron11

vulcanised EPDM rubber­coating

Corrosion protection for DN 80 – 600:

The body is internally vitreous-enamelled and externally EKB coated (synthetic epoxy
coating). All other parts are made of stainless materials.
Recesses are provided at the centering of the internal body in the main body so that the
transitions between the uncoated and coated surface can be filled with sealing agent.
This protects and seals these critical areas against the flow medium.

1.3 Performance and Mode of Operation

The ERHARD NON SLAM Nozzle Check Valve is a flow-controlled non-return valve
with centrally and axially moved obturator. This obturator with the shape of a valve disc
(DN 80 – 300) or a valve ring (for DN 350 and larger) is guided by means of one (four) a
guiding stem(s) in an internal body. The closing movement of the valve is spring­assisted (one or four springs).

The ERHARD NON SLAM Nozzle Check Valve is resilient-seated, with tight closure
according to DIN EN 12266 / 1074 – leakage rate 1 (0 drop per minute), at a minimum
back pressure of 4.0 mWC (400 mbar) and larger for DN 80 – 300 and a minimum back
pressure of 8.0 mWC (800 mbar) and larger for DN 350 – 600.

The valve starts opening at incipient velocity and is fully open at a velocity of approx. 2
m/s. The opening process can be influenced by a special spring which is designed for
special cases of application.

The standard design is suitable for installation in horizontal pipeline and for vertical
pipeline and for vertical upward flow. When the valve is installed in a vertical pipeline
with downward flow, the ERHARD NON SLAM Nozzle Check Valve has to be equipped
with a special spring. Moreover, a remachined internal body is used which is designed
with additional bores for drainage of the internal body (see fig. 1.1 and 1.2).

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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1.4 Application according to the rules

Thanks to their design, the ERHARD NON SLAM Nozzle Check Valves are applied
according to the General Instructions BA01E001 Section 1.1.

1.5 Transport and storage

1.5.1 Transport
It is not allowed to attach the lifting gears in the flange holes or to roll the valve on the

outside diameter of the flanges which would damage the corrosion protection.
Weights of the ERHARD NON SLAM Nozzle Check Valves:

DN 80 100 125 150 200 250 300 350 400 500 600

PN

10
16
25
40

The ERHARD NON SLAM Nozzle Check Valves DN 300 and smaller should be
transported by means of belts which are to be placed around the flange necks and to
be suspended at the lifting gear (see fig. 1.3).

The ERHARD NON SLAM Nozzle Check Valves DN 350 to 600 are provided with
threaded holes (M16) at the flanges. Thus, it is possible to transport the ERHARD
Check Valves by means of eyebolts.

----50,070,0100,0 130,0 160,0 260,0 420,0
14,0 19,0 27,0 32,5 50,0 70,0 100,0 135,0 16 5,0 275,0 480,0
14,0 19,0 27,0 40,0 56,5 81,5 113,0 - - - ­14,0 19,0 27,0 40,0 67,5 101,0 145,5 - - - -

in kg

Weight approx.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 9 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Fig. 4.2: Installation in vertical

Fig. 1.3: Installation in horizontal pipeline

pipeline

(left hand: Check Valve DN 80 – 300, right
hand: Check Valve DN 350 – 600)

For installation into vertical pipeline insert two bolts of appropriate material and strength
into two opposite flange holes to which the belts are fixed at the flange back (see fig.

1.4). Please provide protective devices at the bolts (e.g. sleeves of plastic material ...)
for protecting the coating of the flange holes.

1.5.2 Storage
The ERHARD NON SLAM Nozzle Check Valves are to be secured by means of wedges

or belts (fig 1.5) against rolling off, or good stability has to be ensured by putting them
horizontally on the flange (fig. 1.6).

BA43E000
Juli 2009
Rev.9

Fig. 1.5 Fig.1.6

1.6 Installation into the Pipeline

Remove all packing material from the valve. Prior to installation, check the pipeline
for impurities and foreign bodies and clean it if necessary.

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Attention !

Follow direction of installation
according to the cast-on arrow!

The valve opens in case of flow from A to
B and closes in reverse direction from B to
A, thus preventing backflow!

Fig. 1.7
There must be free access all around the valve for operation and maintenance.
Prior to installation into the pipeline the function of the ERHARD NON SLAM Nozzle

Check Valve can be checked by pressing the obturator onto the stop of the internal
body. When releasing the obturator, the obturator must be pressed into the seat by the
spring, completely and automatically. (Check installation position accordingly.)

ERHARD NON SLAM Nozzle

Check Valve

Serial No.: 000000/00/00

Admiss.work.pressure PFA __bar

Flanges PN ??

Sealing material: NBR

Spring: standard

Position of installation: →↑

Fig. 5.2 Standard nameplate

During installation of the valve, the distance between the pipe flanges should exceed
the valve face-to-face dimension by at least 20 mm. Thus, the raised faces will not be
damaged and the gaskets can be inserted. Up to PN 16 textile reinforced rubber seals
are recommended for use as flange gaskets. Steel-reinforced rubber seals are
recommended for PN 25 and higher. For slip-on flanges, they are absolutely
necessary. (Consider resistance to flow medium and temperature.)
The mating pipe flanges must be plain-parallel and concentric.

Tighten the connecting bolts evenly (without distortion) and crosswise. The pipeline
mustn't by any means be pulled up to the valve.

Installation in horizontal and vertical pipeline is
possible. For installation in vertical pipeline with
upward flow a standard spring is used as for
installation in horizontal pipeline. The installation
position is marked on the nameplate (5.2). The
springs for the standard case (→ ↑) are marked
accordingly – like all the other springs.
A special spring is used for installation in vertical
pipeline with downward flow (↓). In this case, the
internal body has an additional bore.

BA43E000
Juli 2009
Rev.9

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Page 11 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Warning

Follow the applicable safety rules according to

VGB 9a and wear the

Warning

necessary personal protective equipment.

Risk of injury!

During transport or installation of the
ERHARD NON SLAM Nozzle Check

Valves, there may be the risk of

Attention! Risk of bruises!

Risk of penetration of flow medium!
Prior to putting into operation and after carrying out maintenance work, check
tightness of the flange connections and screwed connections if any or replace the
seals.

Attention: For DN 300 – 600, the guiding stems exceed the face-to-face
dimension of the valve in fully open position (see Tables
"Dimensions of ERHARD NON SLAM Nozzle Check Valves DN 80 -
300" and "Dimensions of ERHARD NON SLAM Nozzle Check Valves
350 – 600". Consider corresponding valves or fittings downstream of
the valve!

Installation directly upstream or downstream of bends, T-pieces or valves has
to be avoided.

bruising the fingers by uncontrolled

movement of the obturator.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 12 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Note concerning installation:

We recommend to design the non-return
valve in the nominal size DN of the
delivery side of the pump. (DN of pump =
DN of ERHARD NON SLAM Nozzle
Check Valve.)
Thus, there will be – referred to the
nominal size – a higher flow velocity and
thus an optimum operating performance
(opening degree, economic efficiency). If
the ERHARD NON SLAM Nozzle Check
Valve is mounted directly on the delivery
side of the pump, irregular flow and
vibrations of the ERHARD Check Valve
might have negative effects (releasing
screwed connections, damaging the
seals, spring breaking, and increased
wear and tear of the mobile valve and
bearing components).

Therefore we recommend a distance of
min. 5 – 7 x DN (especially for speed­controlled pumps) or a minimum velocity
of 2 – 3 m/s for the ERHARD NON SLAM
Nozzle Check Valve in order to ensure
that the valve is fully open.

BA43E000
Juli 2009
Rev.9

Fig. 1.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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2 Maintenance

Control of the performance and tightness of the ERHARD NON SLAM Nozzle Check
Valve is to be done at regular intervals according to DVGW print W390. Inspection or
repair of the valve must not be carried out before the pipe section in which the valve is
installed has been isolated and made pressure-less.

Warning

In case of penetration of dangerous liquids, substances, gases, and
steams, immediately the plant has to be shut down, the responsible

supervisor must be informed and appropriate repair work has to be

Danger

The personal protective equipment according to the rules of the

employer's liability insurance association must be used. Depending

on the flow medium, there is the risk of poisoning, causticization,

scalding, and danger due to biological and microbiological

substances as well as the risk of fire and explosion!

WARNING
Before carrying out maintenance work on the
valve, any pressurised pipeline has to be
made pressure-less and to be secured
against re-starting!
After finishing the maintenance work, any
connection has to be checked for tightness
and close fit.

DANGER

carried out.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 14 of 18

Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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2.1 Maintenance

ERHARD NON SLAM Nozzle Check Valves are maintenance-free.
Recommended intervals for inspection and maintenance:

Continuous 2 x per year Yearly

ERHARD NON SLAM Nozzle Check
Valve installed in plants

• performance test (Open – Closed)

• tightness test

• head loss measurement

♦
♦

♦

Other checks

• external leakage

• damages

• contamination / ease of operation

• noise

♦
♦

♦

♦

2.2 Spare parts

When spare parts are required, it is necessary to specifiy the serial number of the valve.
The serial number is specified on the name plate (fig. 1.8). All data required for
selecting the appropriate spare parts are assigned to the serial number.

For 2 and 5 years‘operation wearing parts are not necessary.
The following spare parts for the ERHARD NON SLAM Nozzle Check Valve are defined

as wearing parts:

ERHARD NON SLAM Nozzle Check Valves DN 80 – 300:

1. Completely mounted unit (if necessary):
rubber-coated valve disc (1) with
guiding stem (2) and washer (5).

2. Spring (3)
(if necessary)

3. Bush (4) 2 pieces

Fig. 2.1

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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ERHARD NON SLAM Nozzle Check Valves DN 350 - 600:

1. Completely mounted unit (if

necessary): rubber-coated valve
ring (1) with 4 guiding stems (2) and
washers (5).

2. Springs (3)
(if necessary) 4 pieces

4. Bushes (4) 4 or 8 pieces

Fig. 2.2

2.3 Replacement of the spare parts / necessary tools

For replacing above mentioned wearing parts, the ERHARD NON SLAM Nozzle Check
Valve has to be removed from the pipeline after having depressurized the pipeline. The
internal body (2) is secured in the body (3) in the following manner:

- for sizes DN 80 to 300 with 3 threaded pins M6 with internal hexagon 3 mm (1),

- for sizes DN 350 to 500 with 4 threaded pins M6 with internal hexagon 3 mm (1) and

- for size DN 600 with 4 threaded pins M8 with internal hexagon 4 mm.
These pins must be screwed off.

DN 80 – 300:

For removing the internal body (2) from
the body (3), a force of approx. 20 kN
is required. This force can be applied
by means of a press, an auxiliary
mounting tool or similar device as
shown in fig. 2.3.1.

The tool is centrally placed on the
pushed back valve disc, both bolts are
tightened in two opposite flange holes
with washers and nuts, parallel to the
raised face. The internal body is
pressed out of the main body by means
of the central bolt (4). When pressing
the internal body out of its position, it
should be held in order to avoid
damage to the coating.

BA43E000
Juli 2009
Rev.9

Fig. 2.3.1

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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DN 350 – 600:

For removing the internal body (2) from
the body (3), a force of approx. 40 kN
is required. This force can be applied
by means of a press, an auxiliary
mounting tool or similar device as
shown in fig. 2.3.2.
The tool is centrally placed on the
pushed back valve ring so that the
bolts (4) required for expulsion are
centrally arranged on the width of the
valve ring. The two fastening bolts are
tightened in two opposite flange holes
with washers and nuts, parallel to the
raised face.

The internal body is pressed out of the
main body, screwing-in the bolts (4) in a
slow and uniform manner. When
screwing-in, the corresponding nuts
have
to be secured against following the
bolts. When pressing the internal
body out of its position, it should be
held
in order to avoid damage to the coating.

Fig. 2.3.2

Assembly DN 80 – 600:

During assembly, internal body, valve disc (ring), spring(s), and guiding stem(s) are
pushed into the internal body. The valve disc (ring) can be fixed in its rear limit position
by means of bolt(s) including washer(s) (5), screwed into the guiding stem(s). The fitting
surface (fig. 2.4) of the internal body, has to be cleaned. The body’s fitting surface which
must also be cleaned has to be covered with sealing agent BA51 on the two transitions
to vitreous enamel as well as in the groove in which the threaded pins are engaged.
After having pushed the internal body into the main body, the threaded pins have to be
secured with BA5, too, and screwed into the groove. The internal hexagon of the
threaded pins is filled with BA5 in order to ensure further screwing off. Excessive
sealing agent must be removed from both transitions and be smoothed. For mounting
the internal body in the main body, see also fig. 2.4.

1

Sealing agent BA5 Loctite Deutschland GmbH Type: screw locking, medium strength

Art.-No. 24374

BA43E000
Juli 2009
Rev.9

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Operating Instructions for ERHARD NON SLAM Nozzle Check Valve

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Fig. 2.4:
Curing of the sealing agent takes about 5 hours.

2.4 Troubles during operation of the ERHARD NON SLAM Nozzle Check Valve
and remedies

Trouble Possible Causes Remedy

Leakage in the seat

High head loss

Valve blocked

Increased noise
(closing shocks)

Valves installed in a
wrong way,
contrary to the specified
direction of installation

Deposits or dirt in the seating zone In case of firm incrustations, clean

seating zone and valve disc/ring
Damage to the coating of the valve
disc/ring
Clogging and seizing of the spring Clean spring, in case of very dirty

Deposits on guiding stem Open valve manually several times

Foreign bodies between valve
disc/ring and internal body
Foreign bodies jammed in the
seating zone at v (referred to DN)
<2 m/s
Foreign bodies jammed in the
seating zone at v (referred to DN)
>2 m/s
Return spring broken

Deposits in the guiding device due
to low flow velocity

Pump discharges against closed
valve.
The direction arrow has not been
followed during installation.

Replace valve disc/ring, see

paragraph 2.3

medium: provide spring protecting

device, for dismantling see

paragraph 2.3

until valve can be operated easily

again or dismantle according to

paragraph 2.3 and clean guiding

stem and bore

Manually remove foreign body,

dismantling acc. to 2.3

Increase flow velocity and flush out

foreign bodies

Manually remove foreign bodies

Replacement of spring, see

paragraph 2.3

Cleaning of the bore.

For dismantling, see paragraph

2.3.

Removal of the valve from the

pipeline

Installation into the pipeline, see

1.6.

BA43E000
Juli 2009
Rev.9

ERHARD GmbH & Co. KG x D-89502 Heidenheim x Postfach 1280

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Page 18 of 18