16 TAC §§65.20, 65.50, 65.100
The Texas Department of Licensing and Regulation proposes
amendments to §§65.20, 65.50 and 65.100 concerning the certification
of boilers.
The amendment to §65.20 allows functional processing of boiler installer
applications by the Department. The amendment to §65.50 clarifies the
time frame for notification of risks rejected or suspended due to unsafe conditions
and also provides for data submission by manual or electronic means. The amendment
to §65.100 reflects changes in adopted standards; provides requirements
for atmospheric vents, gas vents, bleed or relief lines on gas regulation
or reducing valves for gas fired boilers applying for extensions to the required
internal inspection interval; and updates referenced standard to latest edition.
The justification for the change to §65.20 is to streamline the functional
processing of boiler installer applications. The justification for the changes
in §65.50 allows the insurance industry to submit electronic data to
the Department. The justification for the changes in §65.100 are to update
the rules to reflect changes in the American Society of Mechanical Engineers
(ASME) Code; clarify requirements of §755.026(e) of the Boiler Law; and
adopt the latest edition and addenda of the National Board Inspection Code
(NBIC).
George R. Bynog, Chief Inspector, Technical Standards-Boiler Section of
the Texas Department of Licensing and Regulation, has determined that for
the first five-year period these sections are in effect there will be no fiscal
implications on state or local government.
Mr. Bynog also has determined that for each year of the first five years
the sections are in effect the public benefit anticipated as a result of enforcing
the sections will be increased safety on new installations, reinstalled boilers,
and repair and alterations on all boilers.
The anticipated economic effect on small businesses and persons who are
required to comply with the sections as proposed will be less down time for
repairs and alterations, greater savings on cost of repairs and installations,
and enhanced communication capabilities.
The cost of compliance is indeterminate at this time for atmospheric vents,
bleed or relief lines, however, there should be no cost involved with the
other amendments.
Comments on the proposal may be submitted to the George Bynog, Chief Boiler
Inspector, Texas Department of Licensing and Regulation, P.O. Box 12157, Austin,
Texas, 78711, facsimile (512) 463-1376, or by e-mail: george.bynog@license.state.tx.us.
The deadline for comments is 30 days after publication in the
Texas Register
.
The amendments are proposed under Texas Health and Safety Code
Annotated, §755 (Vernon 1997) which authorizes the Commissioner of the
Texas Department of Licensing and Regulation to promulgate and enforce a code
of rules and take all action necessary to assure compliance with the intent
and purpose of the Code.
The Code and Article affected by the amendments is Texas Health and Safety
Code Annotated, §755 (Vernon 1997) and Texas Revised Civil Statutes Annotated,
article 9100 (Vernon 1991).
§65.20.Licensing/Certification/Registration Requirements.
(a)-(b)
(No change.)
(c)
Registration.
(1)-(2)
(No change.)
(3)
Authority to install boilers and appurtenances. Only
persons, firms, or corporations registered as installers with the department
are authorized to install boilers and appurtenances provided the following
requirements are met.
(A)
Except as provided by the Texas Boiler Law, Section 75.022,
each boiler installed in this state shall be in accordance with the Texas
Boiler Law and Rules.
(B)
Request for registration will be submitted to the chief
boiler inspector on forms provided by the department. The
department
[
chief boiler inspector
] shall process within 30 days of
receipt provided the application is signed by the individual or an authorized
representative of the firm/corporation.
(C)
If authorization is granted to install boilers and appurtenances,
a certificate of registration will be issued, and it will expire on the triennial
anniversary date. The certificate shall indicate authority and scope to install
boilers. The certificate shall be signed by the commissioner and chief boiler
inspector.
(D)
Renewal notification will be forwarded to the installer
by the department in sufficient time to accomplish the renewal process prior
to the expiration date of the certificate.
(4)
(No change.)
(d)-(i)
(No change.)
§65.50.Reporting requirements.
(a)
(No change.)
(b)
Risks--new, canceled, or suspended.
(1)
All inspection agencies shall [
promptly
] notify
the chief inspector [
, on Form NB-4,
] of all boiler risks written,
[
as well as all boiler risks rejected,
] canceled,
or
not renewed
within 30 days of the effective date
[
, or suspended
because of unsafe conditions
].
Immediate notification shall be
made of all boiler risks rejected or suspended because of unsafe conditions.
Notification may be made electronically or manually
using the
format
[
on Form NB-4 or other forms
] provided by the department.
This notification shall list, by Texas boiler number, all objects affected
by the notice.
(2)
If an authorized inspector, upon the first inspection
of a new risk, finds conditions such that his inspection agency refuses insurance,
the inspection agency shall
immediately
[
promptly
]
notify the chief inspector and submit a report of the defects.
(c)
Inspection report forms. At the time of the first inspection
of any boiler covered by the provisions of the Health and Safety Code, Chapter
755, a complete report [
(including safety or safety relief valve nameplate
data)
] shall be submitted
manually or electronically using the
format
[
on Form NB-5, or other appropriate form,
] provided
by the department. Subsequent inspection reports shall be submitted
manually or electronically using the format
[
on Form NB-6, or other
appropriate form, as
] provided by the department. The reports shall
be submitted within 30 days of the date of the inspection. External inspections
shall be reported
manually or electronically using the format provided
by the department
[
on Form NB-6, or other appropriate form,
]
when hazardous conditions affecting the safety of the boiler are found to
exist or to document the inspection required for extension of the internal
inspection interval.
(d)-(h)
(No change.)
§65.100.Technical requirements.
(a)-(d)
(No change.)
(e)
Atmospheric vents, gas vents, bleed or
relief lines.
(1)
Gas pressure regulators not incorporating integral vent
limiters, and all other gas train components requiring atmospheric air pressure
to balance a diaphragm or other similar device, shall be provided with a connection
for a vent line. These lines shall be sized in accordance with the component
manufacturer's instructions. The vent or relief line shall be at least the
same size as the vent outlet of the device.
(A)
Where there is more than one gas pressure regulator at
a location, each gas pressure regulator shall have a separate vent. The vent
lines may be manifolded in accordance with accepted engineering practices
to minimize back pressure in the event of a diaphragm failure as indicated
in subparagraph (B)(2) and (3) of this subsection.
(B)
A gas pressure regulator shall not be vented into the boiler
flue or exhaust system.
(2)
Atmospheric vent lines, when manifolded, shall
be connected into a common atmospheric vent line having a cross-sectional
area not less than the area of the largest vent line plus 50% of the areas
of the additional vent lines.
(3)
Atmospheric vent lines shall not be connected to any
common or manifolded gas vent, bleed, or relief lines.
(4)
Gas pressure relief valves may discharge into common
manifolding only with other gas vent, bleed, or relief lines. When manifolded,
the common vent line shall have a cross-sectional area not less than the area
of the largest vent line plus 50% of the areas of the additional vent lines.
(5)
Vent and relief lines shall be piped to the outdoors
at a safe point of discharge so there is no possibility of discharged gas
being drawn into the air intake, ventilating system, or openings of any structure
or piece of equipment and shall extend sufficiently above any structure so
that gaseous discharge does not present a fire hazard. A means shall be provided
at the terminating point to prevent blockage of the line by foreign material,
moisture, or insects.
(f)
[
(e)
] Unfired steam boilers.
(1)
Some examples of the unfired steam boilers referred to
in §65.10 of this title (relating to Definitions), are shown in Exhibits
5A and 5B (herein adopted by reference and which exhibits may be secured from
the Texas Department of Licensing and Regulation, Technical Standards--Boiler,
920 Colorado Street, Austin, Texas 78701, or mailing address P.O. Box 12157,
Austin, Texas 78711) of the rules of the Texas Department of Licensing and
Regulation. The limits are defined as the first blinding point, circumferential
welded joint, threaded joint, or flanged joint in the piping connected to
the vessel in which the water is converted into steam. The safety devices,
gages, gage glasses, and similar devices attached to the vessel shall also
be included within these limits.
(2)
Unfired steam boilers as shown on Exhibits 5A and
5B (herein adopted by reference and which exhibits may be secured from the
Texas Department of Licensing and Regulation, Technical Standards--Boiler,
920 Colorado Street, Austin, Texas 78701, or mailing address P.O. Box 12157,
Austin, Texas 78711) of these rules shall be constructed in accordance with
the American Society of Mechanical Engineers (ASME), Section VIII, Division
1.
(3)
Requirements for water level indicators for unfired
steam boilers as shown in Exhibit 5A are given in subsection (h)(3)(D) of
this section.
(g)
[
(f)
] Potable water heaters, unique
requirements.
(1)
Stop valves should be placed in the supply and discharge
pipe connections of a water heater installation to permit draining the heater
without emptying the system.
(2)
Each heater shall have a bottom drain pipe connection
fitted with a valve or cock connected to the lowest water space practicable.
The minimum size bottom drain shall be 3/4 inch.
(3)
Each water heater shall have a thermometer located
and connected at or near the outlet that is easily readable. The thermometer
shall at all times indicate the temperatures of the water in the hot water
heater.
(4)
When the water supply to a water heater exceeds 75%
of the design pressure of the heater, a pressure-reducing valve shall be required.
(h)
[
(g)
] Nuclear boilers.
(1)
Nuclear boilers shall be inspected inservice by the owner
or operator in accordance with ASME Boiler and Pressure Vessel Code, Section
XI.
(2)
The owner or operator shall engage the services of
an inspection agency, qualified in accordance with American National Standards
Institute/American Society of Mechanical Engineers (ANSI/ASME) N626.1, licensed
by the Texas State Board of Insurance, and authorized to provide inspection
services by the commissioner.
(3)
The chief inspector shall assign, after receipt of
the completed N-3 owner's data report, a state serial number to the nuclear
boiler.
(A)
All N-5 data reports for piping systems and N-3 owner's
data reports shall be filed with the chief inspector.
(B)
National Board registration described in §65.50(a)
of this title (relating to Reporting Requirements) or §65.20(c)(1)(D)
of this title (relating to Licensing/Certification/Registration Requirements)
is not required.
(4)
The certificate of operation will be issued after
receipt of the preservice inspection summary report and prior to commercial
service. The summary report shall include all activities required by ASME
Code, Section XI, except for the results of examinations or test of items
obtainable only during power ascension testing. These items shall be filed
as an amendment to the summary report within 60 days of the completion of
the power ascension testing. These items identified to be submitted in the
amendment shall be agreed upon by mutual consent as provided for in paragraph
(11) of this subsection prior to power ascension testing and issuance of the
certificate of operation.
(5)
The inservice inspection plan shall be submitted to
the chief inspector by the owner or operator prior to commercial service.
(6)
The chief inspector shall review the inservice inspection
plan and select those items necessary to verify compliance with the Health
and Safety Code, Chapter 755, and ASME Code, Section XI. Items selected for
verification shall be from within the verification boundary of the nuclear
boiler consisting of the components and component supports of the systems
illustrated in Exhibit 6 (herein adopted by reference and which exhibit may
be secured from the Texas Department of Licensing and Regulation, Technical
Standards--Boiler, 920 Colorado Street, Austin, Texas 78701, or mailing address
P.O. Box 12157, Austin, Texas 78711).
(7)
The chief inspector shall, upon reasonable notification
by the owner or operator of inservice inspection activities to be accomplished
during any outage on items selected in subsection (f) of this section, coordinate
with the owner or operator the verification activities.
(8)
The chief inspector shall review and maintain summary
reports of the inservice inspections that are submitted by the owner or operator
in accordance with ASME Code, Section XI.
(9)
Repairs and/or replacements shall conform to the requirements
of ASME Code, Section XI.
(10)
The owner or operator shall, in case of serious accidents
to a nuclear boiler involving a breach of the pressure boundary integrity
of components included in Exhibit 6 (herein adopted by reference and which
exhibit may be secured from the Texas Department of Licensing and Regulation,
Technical Standards--Boiler, 920 Colorado Street, Austin, Texas 78701, or
mailing address P.O. Box 12157, Austin, Texas 78711) immediately notify the
chief inspector by the most expeditious means available and apprise him of
the nature of the accident. The chief inspector shall assess the nature of
the accident, formulate inspection activities as required, and coordinate
these activities with the owner or operator and as necessary with other state
and federal agencies having jurisdiction.
(11)
If exceptions or situations arise which are not specifically
addressed in this section or other sections of the Boiler Law and Rules, or
in ASME Code, Section XI, the owner or operator shall contact the chief inspector
for guidance or interpretation.
(i)
[
(h)
] Power boilers.
(1)
Safety valves and safety relief valves.
(A)
The use of weighted-lever safety valves, or safety valves
having either the seat or disk of cast iron, is prohibited.
(B)
Each boiler shall have at least one safety valve and, if
it has more than 500 square feet of water heating surface or has an electric
power input more than 1,100 kilowatts, it shall have two or more safety valves.
(C)
The valve or valves shall be connected to the boiler, independent
of any other steam connection, and attached as close as practicable to the
boiler without unnecessary intervening pipe or fittings.
(D)
No valves of any description shall be placed between the
required safety valve or safety relief valve or valves and the boiler, except
for unfired steam as shown in Exhibits 5A and 5B (herein adopted by reference
and which exhibits may be secured from the Texas Department of Licensing and
Regulation, Technical Standards--Boiler, 920 Colorado Street, Austin, Texas
78701, or mailing address P.O. Box 12157, Austin, Texas 78711) nor on the
discharge pipe between the safety valve or safety relief valve and the atmosphere.
When a discharge pipe is used, it shall be at least full size of the safety
valve discharge and fitted with an open drain to prevent water lodging in
the upper part of the safety valve or discharge pipe. When an elbow is placed
on a safety valve discharge pipe, it shall be located close to the safety
valve outlet. The discharge pipe shall be securely anchored and supported.
All safety valve or safety relief valve discharges shall be located or piped
to be carried to a safe point of discharge clear from walkways or platforms
used for access to main stop valves of boiler or steam header.
(E)
The safety valve capacity of each boiler must allow the
safety valve or valves to discharge all the steam that can be generated by
the boiler without allowing the pressure to rise more than 6.0% above the
highest pressure to which any valve is set, and to no more than 6.0% above
the maximum allowable working pressure.
(F)
One or more safety valves on every boiler shall be set
at or below the maximum allowable working pressure. The remaining valves may
be set within a range of 3.0% above the maximum allowable working pressure,
but the range of setting of all the safety valves on a boiler shall not exceed
10% of the highest pressure to which any valve is set.
(G)
When two or more boilers operating at different pressures
and safety valve settings are interconnected, the lower pressure boilers or
interconnected piping shall be equipped with safety valves of sufficient capacity
to prevent overpressure, considering the maximum generating capacity of all
boilers.
(H)
In those cases where the boiler is supplied with feedwater
directly from water mains without the use of feeding apparatus (not to include
return traps), no safety valve shall be set at a pressure higher than 94%
of the lowest pressure obtained in the supply main feeding the boilers.
(I)
If there is any doubt as to the capacity of the safety
valve, an accumulation test shall be run. See ASME Code, Section I, Power
Boilers.
(2)
Feedwater supply.
(A)
Each boiler shall have a feedwater supply which will permit
it to be fed at any time while under pressure.
(B)
A boiler having more than 500 square feet of water heating
surface shall have at least two means of feeding, one of which should be a
pump, injector, or inspirator. A source of feed directly from water mains
at a pressure of at least 6.0% greater than the set pressure of the safety
valve with the highest setting may be considered as one of the means of feeding.
Boilers fired by gaseous, liquid, or solid fuel in suspension may be equipped
with a single means of feeding water, provided means are furnished for the
immediate shutoff of heat input if the feedwater is interrupted.
(C)
Feedwater shall not be discharged close to riveted joints
of shell or furnace sheets or directly against surfaces exposed to products
of combustion or to direct radiation from the fire.
(D)
Feedwater piping to the boiler shall be provided with a
check valve near the boiler and a stop valve or cock between the check valve
and the boiler. When two or more boilers are fed from a common source there
shall also be a stop valve on the branch to each boiler between the check
valve and the source of supply. Whenever a globe valve is used on the feedwater
piping, the inlet shall be under the disk of the valve.
(E)
In all cases where returns are fed back to the boiler by
gravity, there shall be a check valve and stop valve in each return line,
the stop valve to be placed between boiler and the check valve, and both shall
be located as close to the boiler as is practicable. It is recommended that
no stop valve be placed in the supply and return pipe connections of a single
boiler installation.
(F)
Where deaerating heaters are not used, it is recommended
that the temperature of the feedwater be not less than 120 degrees Fahrenheit
to avoid the possibility of setting up localized stress. Where deaerating
heaters are used, it is recommended that the minimum feedwater temperature
be not less than 215 degrees Fahrenheit so that dissolved gases may be thoroughly
released.
(3)
Water level indicators.
(A)
Each boiler, except forced-flow steam generators with no
fixed steam and waterline, and high temperature water boilers of the forced
circulation type that have no steam and waterline, shall have at least one
water gage glass.
(B)
Except for electric boilers of the electrode type, boilers
operated at pressures over 400 psig shall be provided with two water gage
glasses, which may be connected to a single water column or connected directly
to the drum.
(C)
Two independent remote level indicators may be provided
instead of one of the two required gage glasses for boiler drum water level
indication, in the case of boilers with all drum safety valves set at or above
400
[
900
] psig. When both remote level indicators are in
reliable operation, the remaining gage glass may be shut off, but shall be
maintained in serviceable condition.
(D)
Each steam drum of an unfired steam boiler, irrespective
of pressure and temperature, as shown in Exhibit 5A shall be provided with
one direct reading water level indicator (water gage glass) or two independent
remote level indicators that are maintained in simultaneous operation while
the boiler is in service.
(E)
In all installations where direct visual observations of
the water gage glass(es) cannot be made, two remote level indicators shall
be provided at operational level.
(F)
The gage cock connections shall not be less than 1/2 inch
pipe size.
(G)
No outlet connections, except for damper regulator, feedwater
regulator, drains, steam gages, or apparatus of such form as does not permit
the escape of an appreciable amount of steam or water there from, shall be
placed on the pipes connecting a water column or gage glass to a boiler.
(H)
The water column shall be fitted with a drain cock or drain
valve of at least 3/4 inch pipe size. The water column blowdown pipe shall
not be less than 3/4 inch pipe size and shall be piped to a safe point of
discharge.
(I)
Connections from the boiler to remote level indicators
shall be at least 3/4 inch pipe size to, and including the isolation valve
and at least 1/2 inch OD tubing from the isolation valve to the remote level
indicator. These connections shall be completely independent of other connections
for any function other than water level indication.
(4)
Pressure gages.
(A)
Each boiler shall have a pressure gage that is easily readable.
The dial of the pressure gage shall be graduated to approximately double the
pressure at which the safety valve is set, but in no case, less than one and
one-half times this pressure. The pressure gage shall be connected to the
steam space, to the water column, or its steam connection. A valve or cock
shall be placed in the gage connection adjacent to the gage. An additional
valve or cock may be located near the boiler providing it is locked or sealed
in the open position. No other shutoff valves shall be located between the
gage and the boiler. The pipe connection shall be of ample size and arranged
so that it may be cleared by blowing down. For a steam boiler, the gage or
connection shall contain a siphon or equivalent device which will develop
and maintain a water seal that will prevent steam from entering the gage tube.
(B)
Each boiler must have a valved connection at least 1/4
inch pipe size connected to the steam space for the exclusive purpose of attaching
a test gage when the boiler is in service to test the accuracy of the pressure
gage.
(5)
Stop valves.
(A)
Each steam outlet from a boiler (except safety valve connections)
shall be fitted with a stop valve located as close as practicable to the boiler.
(B)
When a stop valve is located that allows water to accumulate,
ample drains shall be provided. The drain shall be piped to a safe location
and shall not be discharged on the boiler or its setting.
(C)
When boilers provided with manholes are connected to a
common steam main, the steam connection from each boiler shall be fitted with
two stop valves with an ample drain between them. The discharge of the drain
shall be visible to the operator while manipulating the valves and shall be
piped clear of the boiler setting. The stop valves shall consist preferably
of one automatic nonreturn valve (set next to the boiler) and a second valve
of the outside-screw-and-yoke type.
(6)
Blowdown connection.
(A)
The construction of the setting around each blowdown pipe
shall permit free expansion and contraction. These setting openings must be
sealed without restricting the movement of the blowdown piping.
(B)
All blowdown piping, when exposed to furnace heat, shall
be protected by firebrick or other heat-resisting material, and constructed
to allow the piping to be inspected readily or easily.
(C)
Each boiler shall have a blowdown pipe, fitted with a valve
or cock, in direct connection with the lowest water space. Cocks shall be
of gland or guard type and suitable for the pressure allowed. The use of globe
valves shall be in accordance with ASME code. When the maximum allowable working
pressure exceeds 100 psig, each blowdown pipe shall be provided with two valves
or a valve and cock, such valves and cocks to be adequate for design conditions
of the boiler.
(D)
When the maximum allowable working pressure exceeds 100
psig, blowdown piping from the boiler to the valve or valves shall be run
full size without use of reducers or bushings. The piping shall be at least
extra-heavy steel and shall not be galvanized.
(E)
All fittings between the boiler and blowdown valve shall
be of steel or extra-heavy malleable iron. In case of renewal of blowdown
pipe or fittings, they shall be installed in accordance with the requirements
of the applicable section of the ASME code.
(F)
It is recommended that blowdown tanks be designed, constructed,
and installed in accordance with National Board recommended rules for boiler
blowoff equipment.
(j)
[
(i)
] Heating boilers.
(1)
Safety valves.
(A)
Each steam boiler shall have one or more officially rated
safety valves of the spring pop type adjusted and sealed to discharge at a
pressure not to exceed 15 psig. Seals shall be attached in a manner to prevent
the valve from being taken apart without breaking the seal. The safety valves
shall be arranged so that they cannot be reset to relieve at a higher pressure
than the maximum allowable working pressure of the boiler. A body drain connection
below seat level shall be provided. For valves exceeding two inch pipe size,
the drain hole or holes shall be tapped not less than 3/8 inch pipe size.
For valves two inch pipe size or less, the drain hole shall not be less than
1/4 inch in diameter.
(B)
Each safety valve 3/4 inch or over used on a steam boiler
shall have a substantial lifting device which will positively lift the disk
from its seat at least 1/16 inch when there is no pressure on the boiler.
The seats and disks shall be of suitable material to resist corrosion.
(C)
No safety valve for a steam boiler shall be smaller than
1/2 inch. No safety valve shall be larger than 4-1/2 inches. The inlet opening
shall have an inside diameter approximately equal to, or greater than, the
seat diameter.
(D)
The minimum relieving capacity of valve or valves shall
be governed by the capacity marking on the boiler.
(E)
The minimum valve capacity in pounds per hour shall be
the greater of that determined by dividing the maximum Btu output at the boiler
nozzle obtained by the firing of any fuel for which the unit is installed
by 1,000, or shall be determined on the basis of the pounds of steam generated
per hour per square foot of boiler heating surface as given in the following
table. For cast iron boilers, the minimum valve capacity shall be determined
by the maximum output method. In every case, the safety valve capacity for
each steam boiler shall be such that with the fuel burning equipment installed,
and operated at maximum capacity, the pressure cannot rise more than five
psig above the maximum allowable working pressure.
Figure 1: 16 TAC §65.100(j(1)(E)
[
Figure 1: 16 TAC §65.100 (i)(1)(E)
]
(2)
Safety relief valves.
(A)
Hot water boilers.
(i)
Each hot water heating or supply boiler shall have at least
one officially rated safety relief valve set to relieve at or below the maximum
allowable working pressure of the boiler.
(ii)
When more than one safety relief valve is used on either
hot water heating or hot water supply boilers, the additional valve or valves
shall be officially rated and may have a set pressure within a range not to
exceed six psig above the maximum allowable working pressure of the boiler
up to and including 60 psig, and 5.0% for those having a maximum allowable
working pressure exceeding 60 psig.
(iii)
Safety relief valves shall be spring loaded. Safety relief
valves shall be set and sealed so that they cannot be reset without breaking
the seal. A body drain connection below seat level shall be provided. For
valves exceeding two inch NPS (nominal pipe size), the drain hole or holes
shall be tapped not less than 3/8 inch NPS. For valves of two inch NPS or
less, the drain hole shall not be less than 1/4 inch in diameter.
(iv)
Each safety relief valve shall have a substantial lifting
device which will positively lift the disk from its seat at least 1/16 inch
when there is no pressure on the boiler.
(v)
Seats and disks of safety relief valves shall be made of
a suitable material to resist corrosion. No materials likely to fail due to
deterioration or vulcanization, when subjected to saturated steam temperature
corresponding to capacity test pressure, shall be used for any part.
(vi)
No safety relief valve shall be smaller than 3/4 inch
nor larger than 4-1/2 inch standard pipe size except that boilers having a
heat input not greater than 15,000 Btu/hr may be equipped with a rated safety
relief valve of 1/2 inch standard pipe size. The inlet opening shall have
an inside diameter approximately equal to, or greater than, the seat diameter.
In no case shall the minimum opening through any part of the valve be less
than 1/4 inch in diameter or its equivalent area.
(vii)
The required steam relieving capacity, in pounds per
hour, of the pressure relieving device or devices on a boiler shall be the
greater of that determined by dividing the maximum output in Btu at the boiler
nozzle obtained by the firing of any fuel for which the unit is installed
by 1,000, or shall be determined on the basis of pounds of steam generated
per hour per square foot of boiler heating surface as given in the table in
subsection
(j)(1)(E)
[
(i)(1)(E)
] of this section. For
cast iron boilers the minimum valve capacity shall be determined by the maximum
output method.
(viii)
In every case, the safety relief valve capacity for
each boiler with a single safety relief valve shall be such that, with the
fuel burning equipment installed and operated at maximum capacity, the pressure
cannot rise more than 10% above the maximum allowable working pressure. When
more than one safety relief valve is used, the overpressure shall be limited
to 10% above the set pressure of the highest set valve.
(B)
Potable water heaters.
(i)
Potable water heaters (tank type) shall have at least one
pressure temperature relief valve of the automatic reseating type set to relieve
at or below the maximum allowable pressure of the heater.
(ii)
The relief valve shall have a capacity equal to or exceeding
the rated burner input of the heater.
(iii)
The ASME Btu rating on the valve shall be used to determine
the relieving capacity.
(iv)
Relief valves shall be connected directly to the heater
within the top six inches of the tank.
(v)
Relief valves may be installed vertically or horizontally.
The center line of the horizontal connection shall be no lower than four inches
from the top of the shell.
(vi)
Relief valves shall not be connected to an internal pipe
in the heater, or to a cold water feed line connected to the heater.
(3)
Safety valve and safety relief valve piping.
No valve shall be placed between the safety valve or safety relief valve and
the boiler nor on the discharge pipe between the safety valve and the atmosphere
or the safety relief valve and the drain. When a discharge pipe is used, it
shall be full size and fitted with an open drain to prevent water from lodging
in the upper part of the safety valve or relief valve or in the discharge
pipe. When an elbow is placed on the safety valve or relief valve discharge
pipe, it shall be located close to the valve outlet. The discharge pipe shall
be securely anchored and supported, independent of the valve.
(4)
Pressure gages.
(A)
Steam heating boilers.
(i)
Each steam heating boiler shall have a pressure gage connected
to the steam space, water column, or steam connection by a siphon or equivalent
device exterior to the boiler. The gage shall be of sufficient capacity to
keep the gage tube filled with water and arranged so that the gage cannot
be shut off from the boiler except by a cock with tee or lever handle placed
in a pipe
near the gage. The handle of the cock shall be parallel to
the pipe
in which it is located when the cock is open.
(ii)
The scale on the dial of a steam heating boiler pressure
gage shall be graduated to not less than 30 psig nor more than 60 psig. The
travel of the pointer from zero to 30 psig pressure shall be at least three
inches.
(B)
Hot water heating boilers or hot water supply.
(i)
Each hot water heating boiler shall have a pressure or
altitude gage connected to it or to its flow connection which cannot be shut
off from the boiler except by a cock with tee or lever handle placed on the
pipe near the gage. The handle of the cock shall be parallel to the pipe in
which it is located when the cock is open.
(ii)
The scale on the dial of the pressure or altitude gage
shall be graduated to not less than one and one-half nor more than three times
the pressure at which the safety relief valve is set. The gage shall be provided
with effective stops for the indicating pointer at the zero point and at the
maximum pressure point.
(iii)
Piping and tubing for pressure or altitude gage connections
shall be of nonferrous metal when smaller than one-inch pipe size.
(5)
Water gage glasses.
(A)
Each steam heating boiler shall have one or more water
gage glasses attached to the water column or boiler by means of valved fittings.
The lower fitting shall have a drain valve of the straightway type with opening
not less than 1/4 inch diameter to facilitate cleaning. Gage glass replacement
shall be possible under pressure.
(B)
Transparent material, other than glass, may be used for
the water gage provided that the material has proved suitable for the pressure,
temperature, and corrosive conditions encountered in service.
(6)
Stop valves.
(A)
Single steam heating boilers. When a stop valve is used
in the supply pipe connection of a single steam heating boiler, there shall
be one used in the return pipe connection.
(B)
Single hot water heating boilers.
(i)
Stop valves shall be located at an accessible point in
the supply and return pipe connections near the boiler nozzle of a single
hot water heating boiler installation to permit draining the boiler without
emptying the system.
(ii)
When the boiler is located above the system and can be
drained without draining the system, stop valves may be eliminated.
(C)
Supply and return line. Each supply and return line to
a steam heating boiler, which may be entered while adjacent boilers are in
operation, shall be fitted with either two stop valves with ample drain between
or a stop valve and figure 8 blank. The blank shall be installed between the
stop valve and the boiler.
(D)
Type of stop valve. When stop valves over two inches in
size are used, they shall be of the outside screw-and-yoke rising stem type
or of such other type as to indicate at a distance whether it is closed or
open by the position of its stem or other operating mechanism. The wheel may
be carried either on the yoke or attached to the stem. If the valve is of
the plug cock type, it shall be fitted with a slow opening mechanism and an
indicating device and the plug shall be held in place by a guard or gland.
(E)
Identification of stop valves by tag. When stop valves
are used, they shall be properly designated, substantially as follows, by
tags of metal or other durable material fastened to them.
Figure 2: 16 TAC §65.100(j)(6)(E)
(7)
Feedwater connections.
(A)
Feedwater, makeup water, or water treatment shall be introduced
into a boiler through the return piping system or through an independent feedwater
connection which does not discharge against parts of the boiler exposed to
direct radiant heat from the fire. Feedwater, makeup water, or water treatment
shall not be introduced through openings or connections provided for inspection
or cleaning, safety valve, or safety relief valve, surface blowoff, water
column, water gage glass, pressure gage, or temperature gage.
(B)
Feedwater pipe shall be provided with a check valve near
the boiler and a stop valve or cock between the check valve and the boiler
or return pipe system.
(8)
Bottom blowdown or drain valve.
(A)
Bottom blowoff valve. Each boiler shall have a bottom blowoff
connection to the lowest water space practicable with a minimum size as shown
in the following table. The discharge piping shall be full size to the point
of discharge. Boilers having a capacity of 25 gallons or less are exempt from
these requirements.
Figure 3: 16 TAC §65.100(j)(8)(A)
[
Figure 2: 16 TAC §65.100(i)(8)(A)
]
(B)
Drain valve. Each boiler shall have one or more drain connections,
fitted with valves or cocks connecting to the lowest water containing spaces.
The minimum size of the drain piping, valves, and cocks shall be 3/4 inches.
The discharge piping shall be full size to the point of discharge. When the
blowoff connection is located at the lowest water containing space, a separate
drain connection is not required.
(C)
Minimum pressure rating. The minimum pressure rating of
valves and cocks used for blowoff or drain purposes shall be at least equal
to the pressure stamped on the boiler, but in no case less than 30 psig. The
temperature rating of such valves and cocks shall not be less than 250 degrees
Fahrenheit.
(9)
Provisions for thermal expansion.
(A)
Hot water heating boiler. If the system is of closed type,
an airtight tank or other suitable air cushion that is consistent with the
volume and capacity of the system shall be installed, and it shall be suitably
designed for a hydrostatic test pressure of two and one-half times times the
allowable working pressure of the system. Expansion tanks for systems designed
to operate above 30 psig shall be constructed in accordance with ASME Code,
Section VIII, Division 1. Provision shall be made for draining the tank without
emptying the system, except for pre-pressurized tanks.
(B)
Potable water heater. If a system is equipped with a check
valve or pressure-reducing valve in the cold water inlet line, an airtight
expansion tank or other suitable air cushion shall be considered. When an
expansion tank is provided, it shall be constructed in accordance with ASME
Code, Section VIII, Division 1, for a maximum allowable working pressure equal
to or greater than the water heater. Provision shall be made for pre-pressurized
tanks.
(k)
[
(j)
] Repairs and alterations. Repairs
and alterations shall conform to the requirements of the National Board Inspection
Code (NBIC)
1995
[
1989
] edition; and shall be acceptable
to the inspector, except that repairs and alterations may be performed by
the following provided the intended work is within the scope of the issued
certificate of authorization:
(1)
holders of the appropriate certificate(s) of authorization
from the American Society of Mechanical Engineers; or
(2)
holders of a certificate of authorization from the
National Board of Boiler and Pressure Vessel Inspectors for use of the R repair
symbol stamp; or
(3)
owner/operators of boilers who have been issued a
certificate of authorization by the Texas Department of Licensing and Regulation.
(A)
Issuance of the certificate of authorization will be made
upon submission of an application, on forms provided by the department.
(B)
Review of the applicant's program and facilities initially
and at subsequent three-year intervals will be done.
(i)
The review will determine the applicant has a documented
program to control repairs and/or alterations conforming to minimum requirements
established by the department.
(ii)
The review will require demonstration of the applicant's
ability to perform repairs and/or alterations by implementing on representative
work the requirements of the written program.
(l)
[
(k)
] Lap seam cracks. The shell
or drum of a boiler in which a typical lap seam crack is discovered along
a longitudinal riveted lap-type joint shall be immediately and permanently
discontinued for use under pressure. A lap seam crack is the typical crack
frequently found in lap seams, which extends parallel to the longitudinal
joint and is located either between or adjacent to rivet holes.
(m)
[
(l)
] Hydrostatic tests.
(1)
When there is a question or doubt about the extent of a
defect found in a boiler, the inspector may require a hydrostatic test.
(2)
In preparing a boiler for a hydrostatic test, the
boiler shall be filled with water to the stop valve and all air vented off.
If the boiler to be tested is connected with other boilers that are under
pressure, such connections shall be blanked off unless they have double stop
valves on all connection pipes with a drain between.
(3)
During a hydrostatic test of a boiler, the safety
valve or valves shall be removed or each valve disc shall be held to its seat
by means of a testing clamp and not by screwing down the compression screw
under the spring.
(4)
The minimum temperature of the water used to apply
a hydrostatic test shall be 70 degrees Fahrenheit, but the maximum temperature
shall not exceed 120 degrees Fahrenheit.
(5)
When a hydrostatic test is to be applied after inspection,
the pressure shall be as follows.
(A)
For all cases involving the question of tightness, the
pressure shall be equal to the set pressure of the safety valve or valves
having the lowest setting.
(B)
For all cases involving the question of safety, the pressure
shall be equal to one and one-half times the maximum allowable working pressure.
(C)
The pressure applied for a hydrostatic test shall not exceed
one and one-half times the maximum allowable working pressure. In no case
shall the test pressure be exceeded by more than 2.0%.
This agency hereby certifies that the proposal
has been reviewed by legal counsel and found to be within the agency's legal
authority to adopt.
Filed with the Office of the Secretary of State, on
January 11, 1999.
TRD-9900105
Rachelle A. Martin
Executive Director
Texas Department of Licensing and Regulation
Earliest possible date of adoption: February 21, 1999
For further information, please call: (512) 463-7348