815 KAR 15:051. Heating boiler supplemental requirements - steam heating, hot water heating and hot water supply boilers

Link to law: http://www.lrc.ky.gov/kar/815/015/051.htm
Published: 2015

      815 KAR 15:051.

Heating boiler supplemental requirements - steam heating, hot water heating and

hot water supply boilers.

 

      RELATES TO: KRS

236.030

      STATUTORY AUTHORITY:

KRS 236.030

      NECESSITY, FUNCTION,

AND CONFORMITY: KRS 236.030 authorizes the executive director, through the

Board of Boiler Rules, to fix reasonable standards for the safe construction,

installation, inspection and repair of boilers and pressure piping. This administrative

regulation sets forth requirements for heating boilers which supplement the

basic requirements for all vessels set forth in 815 KAR 15:025 and 815 KAR

15:026. Many of the provisions have been in effect for some time under the

administrative regulation which preceded this one. This amendment is necessary

to codify additional safety measure applicable only to heating boilers; to

comply with the requirements of KRS Chapter 13A that the administrative

regulation be separated and deal with one (1) topic; and also to allow

mechanical couplings to be used where appropriate.

 

      Section 1. New

Installations. (1) All hot water supply, hot water and steam heating boilers,

except reinstalled boilers and those approved under the "special

design" provisions of 815 KAR 15:025, Section 5, shall be constructed,

stamped, inspected and installed in conformity with the ASME Boiler and

Pressure Vessel Code, Section IV incorporated in 815 KAR 15:025, Section 1(1).

All boilers and pressure vessels shall comply with other applicable provisions

of 815 KAR Chapter 15 of the Kentucky administrative regulations.

      (2) Safety valve

requirements for steam boilers.

      (a) Each steam

boiler shall have one (1) or more officially rated safety valve of the

spring-pop type adjusted and sealed to discharge at a pressure not to exceed

fifteen (15) psi. 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 by the manufacturer and this drain shall not be

plugged during or after field installation. For iron and steel bodied valves

exceeding two (2) inch pipe size, the drain hole, or holes, shall be tapped not

less than three-eighths (3/8) inch pipe size. For valves two (2) inch pipe size

or less, the drain hole shall not be less than one-fourth (1/4) inch in diameter.

      (b) Safety valves

for a steam boiler shall not be smaller than one-half (1/2) inch. Safety valves

shall not be larger than four and one-half (4 1/2) inches. The inlet opening

shall have an inside diameter equal to, or greater than, the seat diameter.

      (c) The minimum

relieving capacity of valve, or valves, shall be governed by the capacity-marking

on the boiler.

      (d) 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 1000, 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 Table "A." In many cases, a greater

relieving capacity of valves will have to be provided than the minimum

specified by the Table. In every case, the requirements of paragraph (e) of

this subsection shall be met.



TABLE

A







MINIMUM

POUNDS OF STEAM PER HOUR PER

SQUARE

FOOT OF HEATING SURFACE







 





Fire

Tube

Boilers





Water

Tube

Boilers







Boiler

Heating Surface







 





Hand

fired





5





6







Stoker

fired





7





8







Oil,

gas or pulverized fuel fired





8





10







Waterwall

Heating Surfaces







 





Hand

fired





8





8







Stoker

fired





10





12







Oil,

gas or pulverized fuel fired





14





16





      1.

When a boiler is fired only by a gas having a heat valve not in excess of 200

BTU per cubic foot, the minimum safety valve or safety relief valve relieving

capacity may be based on the values given for hand fired boilers.

      2.

The minimum safety valve or safety relief valve relieving capacity for electric

boilers shall be three and one-half (3 1/2) pounds per hour kilowatt input.

      3.

For heating surface determination, see ASME Code for Heating Boilers, paragraph

HG403.

      (e)

The safety valve capacity for each steam boiler shall be sufficient to prevent

the pressure from rising more than five (5) psi above the maximum allowable

working pressure when the fuel-burning equipment is installed and operated at

maximum capacity.

      (f)

If operating conditions are changed or additional boiler heating surface is

installed, the valve capacity shall be increased, if necessary, to meet the new

conditions and be in accordance with paragraph (e) of this subsection. If

additional valves are required, they may be installed on the outlet piping, if

there is no intervening valve.

      (3)

Safety relief valve requirements for hot water heating boilers and hot water

supply boilers.

      (a)

Each hot water heating boiler shall have at least one (1) officially rated

pressure relief valve set to relieve at or below the maximum allowable working

pressure of the boiler.

      (b)

Each hot water supply boiler shall have at least one (1) officially rated

pressure/temperature safety relief valve of the automatic-reseating type, set

to relieve at or below the maximum allowable pressure of the boiler.

      (c)

Safety relief valves officially rated as to capacity shall have pop action when

tested by steam.

      (d)

If more than one (1) 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 be set within a range not to exceed six (6) psi above the maximum

allowable working pressure up to and including exceeding sixty (60) psi and

five (5) percent for those having a maximum allowable working pressure

exceeding sixty (60) psi, shall be spring loaded and shall be arranged to

prevent resetting at a higher pressure than the maximum permitted in this

subsection.

      (e)

Materials which are likely to fail due to deterioration or vulcanization when

subjected to saturated steam temperature corresponding to capacity test

pressure shall not be used for any part.

      (f)

Safety relief valves shall not be smaller than three-fourths (3/4) inch, nor

larger than four and one-half (4 1/2) inches, standard pipe size, except that

boilers having a heat input not greater than 15,000 BTU per hour may be

equipped with a rated safety relief valve of one-half (1/2) inch, standard pipe

size; the inlet opening shall have an inside diameter approximately equal to,

or greater than, the seat diameter; and the minimum opening through any part of

the valve shall not be less than one-fourth (1/4) inch diameter, or its

equivalent area.

      (g)

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 1000, or shall be

determined on the basis of pounds of steam generated per hour, per square foot

of boiler heating surface, as given in Table A. In many cases a greater

relieving capacity of valves will have to be provided than the minimum

specified by the Table. In every case, the requirements of paragraph (i) of

this subsection shall be met.

      (h)

If operating conditions are changed or additional boiler heating surface is

installed, the valve capacity shall be increased, if necessary, to meet the new

conditions and shall be in accordance with paragraph (i) of this subsection.

The additional valves required may be installed on the outlet piping if there

is no intervening valve.

      (i)

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 ten (10) percent above the

maximum allowable working pressure when more than one (1) safety relief valve

is used, the over pressure shall be limited to ten (10) percent above the set

pressure of the highest set valve allowed by subsection (2) of this section.

 

      Section

2. Mechanical Couplings for Heating Boilers. (1) Design limits. If mechanical

pipe couplings are used, the pipe, fittings, couplings and gaskets shall have

design ratings by the manufacturer which meet or exceed the operating control

settings of the boiler itself and shall comply with this section.

      (2)

Materials used and location.

      (a)

Piping materials listed in the ASME Code, Section IV, shall be used up to the

first stop valve on supply and return piping.

      (b)

Mechanical pipe couplings tested and listed by a nationally recognized testing

laboratory may then be used in lieu of flanged, threaded or welded joints

within the complete pressure piping system of boilers in which the operating

temperatures shall not exceed 200 degrees Fahrenheit and operating pressures

shall not exceed 100 psig.

      (c)

All mechanical pipe couplings shall be fabricated and installed with strict

adherence to manufacturers written procedures and using only factory approved

tooling.

      (d)

Mechanical couplings shall not be installed unless the temperature controls on

the boiler shall be permanently set to prevent operation in excess of 200

degrees Fahrenheit.

      (3)

Tests. The mechanical coupling shall be subjected to the same hydrostatic

pressures as are applied to test the strength of the boiler (i.e., up to one

and one-half (1 1/2) times the maximum allowable pressure of the boiler).

      (4)

Certification by the contractor. The contractor shall document to the inspector

that the mechanical joints conform to the design and were installed to comply

with the manufacturer procedures, utilizing the materials and equipment

specified and that the temperature and pressure ranges comply with subsection

(2)(b) of this section.

 

      Section

3. Existing Installations, Heating Boilers. (1) ASME Code boilers. The maximum

allowable working pressure of a boiler built in accordance with the ASME Code

shall not exceed the pressure indicated by the manufacturer's identification

stamped or cast upon the boiler or upon a plate secured to it.

      (2)

Noncode riveted boilers. The maximum allowable working pressure on the shell of

a noncode riveted heating boiler shall be determined in accordance with 815 KAR

15:040, Section 2 (power boiler installations) except that the maximum

allowable working pressure of a steam boiler shall not exceed fifteen (15) psi

or a hot water boiler shall not exceed 160 psi at a temperature not to exceed

250 degrees Fahrenheit.

      (3)

Noncode welded boilers. The maximum allowable working pressure of a noncode

steel or wrought iron heating boiler of welded construction shall not exceed

fifteen (15) psi. For other than steam service, the maximum allowable working

pressure shall be calculated in accordance with Section IV of the ASME Boiler

and Pressure Vessel Code.

      (4)

Noncode cast iron boilers.

      (a)

The maximum working pressure of a noncode boiler, composed principally of cast

iron, shall not exceed fifteen (15) psi for steam service or thirty (30) psi

for hot water service.

      (b)

The maximum allowable working pressure of a noncode boiler having cast iron

shell or heads and steel or wrought iron tubes shall not exceed fifteen (15)

psi for steam service or thirty (30) psi for water service.

      (5)

Hydrostatic tests.

      (a)

If repairs are necessary which affect the working pressure or safety of a

boiler, it shall be subjected to a hydrostatic test of the greater of sixty

(60) psig or one and one-half (1 1/2) times the maximum allowable working

pressure that is stamped on the boiler with the exception that cast iron steam

boilers shall be subjected to a hydrostatic test of not less than forty-five

(45) psig.

      (b)

In making hydrostatic pressure tests, the pressure shall be controlled to

prevent the required test pressure from being be exceeded by more than ten (10)

psig.

      (c)

Hydrostatic test water shall be at no less than ambient room temperature, but

in no case less than seventy (70) degrees Fahrenheit, nor high enough to allow

the metal temperature to exceed 120 degrees Fahrenheit.

      (d)

The safety valve or safety relief valve shall be removed or each valve disc

shall be held to its seat by means of a testing clamp.

      (e)

To test for tightness, the test pressure shall be equal to the relieving

pressure of the safety valve having the lowest relief setting.

      (6)

General. If the inspector finds that a steam heating boiler is unsafe for

operation at the pressure previously approved, the pressure shall be reduced,

proper repair made, or the boiler retired from service. (7 Ky.R. 386; eff.

11-6-80; Am. 20 Ky.R. 2735; 2985; eff. 5-18-94; TAm eff. 8-9-2007.)
Read Entire Law on www.lrc.ky.gov