Brown & Brown Mechanical Regulators
I - General
under this contract will entail the removal, restoration, modifications
and reinstallation of three sewer regulators. For this
work the contractor shall engage the services of the original equipment
manufacturer in order to provide a clear channel of responsibility
through the entire process including the final certification of
the restored regulator in place. In accordance with
the following requirements, some new components shall be furnished,
other components reconditioned, and the operating design modified
and the regulator reinstalled. New regulator settings my be
required. Following cleaning of the regulator chambers
by others, the manufacturer shall pre-inspect the chambers to record
component positions and elevations, conditions, then remove the
components, provide transport to the factory, prepare and submit
drawings reflecting the changes, then recondition, return and reinstall
the regulators. Each shall be site tested and certified.
The performance of the equipment shall be guaranteed for period
of one year following acceptance by the engineer. The intent
of this specification is to provide a factory-reconditioned regulator
identical in performance to a new regulator and identical in construction
to the other regulators in the system.
costly equipment shall be reconditioned by the original equipment
manufacturer. The components shall be restored to original
dimensions and tolerances where necessary to achieve the original
Special Equipment for Site Work
must perform all work in accordance with OSHA mandated Confined
total of _____ weeks shall be permitted for the completion of all
of the operations specified including removals, shop work, furnishing
required new components, reinstallation and certification.
II - Specifics
following components shall be removed and shop-reconditioned:
gate body, shutter gate and arms, outboard support, transmission
wheels, pillow blocks and bearings, I-beams and clamps, wall plates,
brackets and clamps, wall collar plate and stuffing box (if any),
the float and float cover plate.
original Type 304 stainless steel components of float guides, float
linkage assembly, shutterage linkage assembly, transmission shaft
and attachment hardware shall be replaced as necessary with identical
components except the replacement materials shall be Type 316 stainless
float shall be shop-reconditioned to include removal and disposal
of the cover plate. The interior is then checked for leaks
and drilled, tapped and plugged where necessary. Interior
weights are checked and corrected supplemented to provide horizontal
positioning of the float when suspended on its linkage. The
interior is then filled with an approved urethane foam. A
new cover plate designed for the modified float guides shall be
furnished and installed with a new plate gasket. Following
these procedures, the exterior shall be sandblasted, primed and
coated with the approved epoxy in accordance with the manufacturer's
is presumed that all of the major components of the regulator gate,
gate body and float can be reconditioned. In the event that
any of these components must be entirely replaced, such replacements
shall be castings which are identical in size, weight, material
specifications and construction to the original components when
new. Fabrications regardless of the materials used shall not be
reconditioned wall-mounted float mechanism shall be reinstalled
using stainless steel anchors. This mechanism must carry the
full weight of the float even when the float chamber is dry, must
duplicate the designed vertical travel of the float and include
easily adjustable stops to limit the upwards and downwards travel
of the float. All new components except the stops shall be
Type 316 stainless steel.
and bearings shall be removed from the transmission shaft.
Disassemble the bearings and pillow blocks, sandblast and epoxy
coat the ferrous components, clean and lubricate the bearings and
replace the bearings end seals. If distorted, re-machine
or replace the seal end plates. Reassemble the pillow
blocks with the bearings using new stainless steel bolts.
The transmission shaft shall be replaced with one of Type 316 stainless
steel machined to the identical dimensions.
wheels or wheel sectors require sharp, clean tracks for the travel
of the chain along the track with a minimum of friction or side
drag. If, after cleaning, the wheels or sectors are determined to
be sound, with tracks that are clear, sharp as machined with no
pitting or erosion, the wheels or wheel sectors may be retained.
For cosmetic purposes, the external surfaces shall be sandblasted
and epoxy coated. Following cleaning, the wheels or wheel sectors
shall be seen by the Engineer for his acceptance prior to further
processing. If the wheels or sectors do not meet the above
criteria, these shall be replaced with new wheels or wheel sectors. The
new wheels or wheel sectors shall exactly match the original wheels
for every dimension. Except that wheel sectors may be substituted
for full wheels in cases where the full wheel circumference will
never by required. They shall be cast iron, ASTM A-48 Class 35,
and machined. The diameters for the machining of the wheel tracks
must be in exact accordance with the original design in order to
the assembled regulator to accommodate the exact flows for which
it was designed.
transmission shall be reassembled using new brass keys and pins.
required to be replaced, all components of the transmission linkages
shall be identical sizes and lengths of welded link Type 316 stainless
steel chain, stainless steel adjusting rods, buckles and carrying
stops shall be epoxy coated. If required, new stainless steel
anchors, nuts and washers shall be used for attachment in their
new wall positions.
gate body shall be sandblasted to bare, clean metal after first
protecting the bronze seat faces. Where these bronze
seat facing bars are joined to the ferrous back surfaces, a careful
inspection shall be made to determine that the original sealant
is intact. If cavities are detected, these shall be repaired
with an approved sealant. If necessary, the convex seating
surface shall be re-machined and honed to the exact original contour.
the removal of the weight carrying bar and protection of the tapped
holes, the shutter gate shall be processed in the same manner as
the gate body. The concave seating surfaces shall be
re-machined where necessary.
shutter gate arms shall be fitted with new bronze bushings where
necessary. Or, the original bushings shall be honed
to established clean, smooth surfaces. The arms shall
be sandblasted and epoxy coated after the bushing are protected.
The adjusting screw tapped holes shall be checked, re-tapped where
necessary, and fitted with new square head or hex head stainless
steel, adjusting screws. Each arm shall be assembled
to its proper trunnion and checked for each of rotation.
Any trunnion defects shall be repaired.
body/arms/shutterage assembly shall be carefully adjusted to produce
the designed 0.006 to 0.010 inch clearances between the convex body
seat face and the concave shutterage seat face. These surfaces
shall be perfectly mated with the use of a lapping/grinding compound
and the repeated cycling of the assembly to lap one surface to exactly
mate with the other. Following the lapping process, all ferrous
surfaces shall be lightly sandblasted again to remove dirt and grease
and then epoxy coated. Seating surfaces shall be protected during
these processes. After thorough drying, the components shall
be reassembled and the clearances between the seating surfaces set
trunnion cover plates can be reused if the surfaces are clean and
capable of producing a seal. Otherwise, new plates shall be
furnished at no additional cost. If perfect, the original
retention studs can be reused. But damaged studs shall be
replaced at no additional cost and replacements shall be Type 316
stainless steel. Grease fittings shall be replaced with Type
316 stainless steel alemite type.
shutterage weight carrying bar shall be reused after sandblasting
and epoxy coating. On this shall be placed the required number
and size of shutter weights to establish equal tension on the shutter
linkage through its entire arc of travel.
there is a wall between the gate chamber and the float chamber,
and if the shaft passes through this wall, there is a center-bearing
packing gland assembly. This is attached to the masonry with
anchors and cast iron lugs. The anchors shall be replaced
with stainless steel. The bearing assembly shall be reconditioned
by sandblasting, epoxy coating and replacement of the packing.
is the intent of this specification to require the epoxy coating
of all ferrous components excepting stainless steel. Each
piece shall be primed immediately following sandblasting, then covered
with two coats of epoxy in accordance with the coating requirements
for the project. Surfaces shall be treated and application
conditions and processes shall be in accordance with the instructions
for the approved coatings that are used.
all of the above processes have been completed, the entire regulator
assembly shall be assembled in the shop and tested in the water.
Exact float submergence shall be established and recorded.
The shutter shall be balanced and the number of shutter weights
that are required shall be recorded. The entire assembly
shall then be balance with the required counterweights added and
their number, size and position recorded. Float submergence,
required weight information and any other information developed
in the test procedures shall be added to a revised arrangement drawing
and furnished to the Engineer together with the Operation and Maintenance
complete regulator shall be reinstalled in the chamber from which
it was removed. Capacity settings shall be as originally
found unless these are changed by the written directions of the
Engineer at the time of and in conjunction with the review for approval
of the submittal drawings.
all restored components are in place, the contractor shall provide
certification that the materials used in the restoration are in
conformance with this specification. Another certification shall
be required to state that the reinstallation is correct to the approved
arrangement drawing. The contractor shall be required to assure
the continued correct performance for a period of one year following
the date of the installation certification and to promptly correct
any condition brought to his attention.
contractor shall not be required to correct malfunctions that result
from the accumulation of silt or debris or entrapments or malfunctions
resulting from improper maintenance or changes by others of placements
or settings of components.
to the start of work, the owner shall provide for the cleaning of
the regulator chambers and the removal and disposal of all materials
that are not a part of the regulator, its chambers including the
diversion chamber and their appurtenances. Once cleaned,
it shall be the responsibility of the owner to maintain clean conditions
through the period of reinstallation of the components and beyond
that period in accordance with the operation and maintenance requirements.