Owner manual

Fulton Thermal Corp.*Electric Thermal Fluid Heaters Manual* Version 2010-0423
Page 37
and packed with Grafoil packing or equal. The valves should have a back seating to allow
re-packing without draining the system. In all units, a “Y” type strainer should be installed
in the fluid return line, between the deaerator tank and the circulating pump.
e) As previously stated, this strainer is provided on all skid-mounted units. Valves must be
provided (unless the heater has been skid-mounted with the tank) so that the strainer can
be isolated for cleaning of the element. The strainer element should be 60 mesh and
must remain in place during normal operation of the system.
f) The pump suction pressure should be checked periodically, under similar operating
conditions. A vacuum reading on the suction gauge indicates that the screen must be
cleaned. For isolating purposes, globe, wedge, gate, ball, or other shut-off valves should
be used. When there is a likelihood that some manual balancing will be required, a ball or
globe valve should be used.
g) Manual control and isolating valves should be the flanged or weld type, manufactured
from cast or forged steel or ductile iron, with internals and gland seals made from
materials suitable for use with high temperature fluids.
h) When ordering valves, the maximum possible service temperature and type of fluid must
be indicated on the order.
i) A partial list of manufacturers known to market valves of acceptable quality follows:
1. Jenkins Brothers
2. Lunkenheimer Company
3. Nibco Incorporated
4. Stockham Valves and Fittings Company
5. Velan
6. Vogt Machine Company
7. Worcester Valve Company
j) Automatic Fluid Control Valves
1. Because of the widely varied processes Fulton Thermal Fluid Heaters
are used in, it is not possible to set down specific rules for the selection
of automatic fluid control valves. Generally, these valves must satisfy the
materials and construction requirements described above.
2. The type of operation and design of porting are governed by the degree
of control required as well as the particular application.
k) Bypass Valves
1. When process flow requirements do not match heater flow requirements,
a by-pass valve must be installed.