Introduction and service problems – Flowserve Edward Cast Steel Bolted Bonnet Valves User Manual

Page 3

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Flow Control Division

Edward Valves

Introduction and Service Problems

Introduction

Cast Steel Bolted Bonnet

This manual has been prepared to serve as
a guide for the maintenance of Edward
bolted bonnet valve construction. It is
designed to help you in obtaining the most
satisfactory service from these valves.
Although rigid metallurgical, radiographic,
physical and visual inspection is the stan-
dard procedure for all Edward products, it
is inevitable that some valves, after a
period of time, may occasionally require
repair. When this happens, this manual
will assist you so that your valve may be
satisfactorily restored to good working
condition with a minimum of time and
expense.
Before starting, it will be helpful to have
some understanding of the valve’s physical
construction. The drawing on pg. 5 will
give you some idea of how the valve is put
together.
The next major section of this manual dis-
cusses the more common service problems
and failures. It identifies the problem and
explains the reasons for certain failures.
The reason should be understood before
work is actually started.
Then the procedure to be followed in mak-
ing the repair is explained. This includes
normal valve maintenance as well as major
valve repair. Field repair equipment, avail-
able from Edward Valves, is described and
illustrated. Valve lubrication and welding
rod recommendations are also made. These
procedures are adequate for almost any
valve repair or maintenance problem that
may arise in the field.

The next major section describes the disas-
sembly procedures for the various valve
components.
It is very important that the Introduction
and the paragraphs titled “First Determine
the Area of Failure” be read and under-
stood before any disassembly work is
begun. Several procedures are described,
depending upon the area of failure.
Considerable time can often be saved by
first selecting the proper disassembly
procedures.
The last major section explains how the
various valve constructions are to be
reassembled. Information on how to
contact Edward Valves for additional
advice, if required, and how to order
parts is included.

FIGURE NUMBER OF EDWARD

BOLTED BONNET VALVES

DESCRIBED IN THIS MANUAL

302

329Y

605Y

1324

302Y

390

618

1324Y

303

390Y

618Y

1390

303Y

391

619

1390Y

304

391Y

619Y

1392

304Y

392

670Y

1392Y

318

392Y

690

1441

318Y

393

690Y

1441Y

319

393Y

691

1443

319Y

394

691Y

1443Y

328

394Y

1302

1641

328Y

604

1302Y

1641Y

329

604Y

1314

1643

605

1314Y

1643Y

SERVICE PROBLEMS

Packing Chamber Leak

Where moisture appears or actual dripping
occurs at the packing chamber around the
stem, gland or gland flange which cannot
be eliminated by re-torquing the gland bolt
the following points should be considered.

1. The packing may have become hard.

Replace the packing.

2. Gland travel has been fully taken up.

Repack with new packing.

3. The wrong packing is being used.

See packing recommendations shown
on this page.

4. A stem should be replaced when it

has become deeply scratched,
burred, or otherwise mutilated from
careless handling, or where the stem
has worn, tapered or has been bent.

5. The gaps in the rings of split packing

have not been staggered around the
stem. They should be inserted in this
manner.

6. The packing gland may be binding

against the packing chamber or stem
and does not compress the packing
properly. Make certain the gland fits
the packing chamber and is tight-
ened down equally on each side.

Packing Recommendations

Edward valves are packed with all-purpose
packing sets. This is a combination of
packing using braided rings at the top and
bottom of the packing chamber and flexi-
ble graphite packing in the center section.
Packing glands should be tightened down

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