Emerson Daniel Senior Orifice Fitting Series, Руководство владельца и оператора

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50 Selecting an appropriate plate change procedure
Section 4: Orifice plate installation and removal instructions Owner and operator manual
January 2015
3-9008-001 Rev M
4.2 Selecting an appropriate plate change procedure
Important
In order to perform a safe and efficient plate change operation with a Senior, the on-site
personnel must evaluate both the service and environmental conditions prior to beginning this
operation. These conditions may have a dramatic effect on the time required for an operator’s
ability to return the Senior to its measurement condition.
As stated in the product description section of this manual, the Seniors utilize a “dual chamber”
design. A slide valve contains the line pressure in the Body (4) during the plate extraction from
the Senior and plate installation into the Senior. Daniel offers both an O-Ring seal “soft
­ seat”
slide valve design, and a grease assisted, metal-to-metal slide valve design. Both designs ensure
the optimum seal performance during this stage in the Orifice Plate (13) change. Under some
service conditions, the grease used in the metal-to-metal slide valve design may migrate into
the Top (14). If this was to occur, then the grease assisted metal-to-metal slide valve may not
perform optimally and leakage will occur.
There are some services where, based on the characteristics of the fluid within and an intimate
knowledge of the system, an operator and owner may allow some leakage past the slide valve
during a plate change operation. This decision to allow leakage should be made on a case by
case basis and be properly documented, communicated to, and acknowledged by, all personnel
involved in the plate change operation. The sole responsibility for a decision to allow leakage lies
with both the product owner and product operator. Daniel recommends that owners and
operators use either the “Quick Change” or “Extended Time” methods described in this section.
Therefore, when performing an Orifice Plate (13) change on a Senior equipped with a grease
assisted, metal-to-metal slide valve, Daniel recommends that at no time shall an operator leave
the Sealing Bar (9 or 9HP), the Sealing Bar Gasket (9A, 9A-HP or 9CF), and the Clamping Bar (12
or 12HP) unfastened from the Top (14) except to remove and replace the Orifice Plate Carrier
(8DM or 8DMC) from the Senior.
Finally, the operator should never leave any Senior, O-Ring seal “soft-seat” slide valve design, or
a grease assisted, metal-to-metal slide valve design, unattended while the Sealing Bar (9 or
9HP), the Sealing Bar Gasket (9A, 9A-HP or 9CF), and the Clamping Bar (12 or 12HP) are
unfastened and removed from the Top (14).
EXPLOSION HAZARD
The Daniel Senior Orifice Fitting contains fluid at elevated pressure. Make sure to follow the
instructions below for proper installation and removal of the plate.
Failure to do so can cause an explosive release and may result in serious injury or death.