Introduction - Emerson CROSBY STYLE HC ISOFLEX Installation, Maintenance And Adjustment Instructions

CROSBY
STYLES HC AND HCA ISOFLEX™ SAFETY VALVES
®
INSTALLATION, MAINTENANCE AND ADJUSTMENT INSTRUCTIONS
FIGURE 2 - STYLE HCA ISOFLEX SAFETY VALVE

2 INTRODUCTION

Crosby Style HC and HCA ISOFLEX safety
valves have been selected because of their
performance features, reliability and ease
of maintenance.
This manual contains information on
installation, hydrostatic testing, field testing
and adjustments and maintenance of these
valves. It is specific to the Isoflex design K
through M orifice sizes. Adherence to the
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installation and maintenance procedures
specified in this manual will provide the utmost
in safety, a minimum of maintenance and a
long service life.
Style HC is a high capacity reaction type safety
valve designed for saturated and superheated
steam applications to temperatures of 750°F.
Crosby Style HCA is a high temperature
version of the Style HC, with an alloy steel
construction suitable to temperatures
up to 1020°F. Typically Style HCA valves are
used for superheaters and reheater outlets.
Details of Style HC and HCA safety valves,
materials of construction, sizes, pressure-
temperature ratings, dimensions, weights and
certified capacities are available on request.
No special tools are necessary for the
maintenance of Style HC and HCA safety valves.
However, tools and equipment are available
to ease disassembly and on site testing of
the valves. Such tools and equipment include
the hydraulic set pressure device, the air
set pressure device (see Figure 15) and the
hydraulic jacking device (see Figure 14).
Detailed instructions on their use can be found
in instructions I-11288, T-1652 and I-1167
respectively.
Whenever Style HC/HCA safety valve parts
names are used in this manual, parts numbers
in parenthesis follow. The parts numbers are
an aid to identifying the parts in Figures 1 and 2
and the correlating parts list.
NOTES
1. Consumable spare parts: valve parts which should
be replaced as part of any disassembly, and discs
and disc inserts which must be replaced if seats
are damaged.
2. Repair spare parts: valve parts exposed to wear
and/or corrosion during normal operation.
They are in fluid flow paths and may require
replacement as part of any repair.
3. Insurance spare parts: valve parts exposed to
process or environmental wear and/or corrosion
and may require replacement as part of a
major repair.
Emerson recommends that sufficient inventory
of spare parts be maintained to support process
requirements. Always be sure to use genuine
Emerson parts to ensure continued product
performance and warranty.
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