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Shape 235 burners

Requirements for upholstered furniture flammability exist in various states, including California, based on California Technical Bulletin 133 (CA TB 133),91 which was also made into a consensus standard by ASTM committee E05 as ASTM E 1537.92 The gas burner used as the ignition source in CA TB 133 is a square-shaped burner that applies propane gas for 80s at a flow rate of 13L/min. The test is severe enough that it can usually not be met, unless the foam contained in the upholstered furniture item is flame-retarded. The pass/fail criteria are a peak heat release rate of 80 kW and a total heat released that does not exceed 25 MJ over the first 10 min of the test. In California, moreover, all foam contained within upholstered furniture must be flame-retarded to comply with CA TB 117. Moreover, the IFC and NFPA 101 both have parallel requirements to those discussed earlier for mattresses. In other words, the 2006 editions of both the codes contain requirements that upholstered furniture items in health care occupancies as well as detention and correctional occupancies that are not sprinklered must comply with a peak heat release rate of 250kW and a total heat release of no more than 40 MJ in the first 5 min of the test, when tested to ASTM E 1537 (or CA TB 133). However, the 2007 edition of the IFC and the 2009 edition of NFPA 101 lowered these values to 80 kW and 25 MJ over 10 min. Finally, the IFC 2007 added college and university dormitories to the list and eliminated the sprinkler exception for detention occupancies. [Pg.614]

Cast and Hand-Molded Refractories. Large shapes such as burner blocks and flux blocks, and intricate shapes such as glass feeder parts saggers are produced by casting sHps, hydraulic cement bonded mixtures, or hand-molding clay or chemically bonded materials. Because these techniques are labor intensive, they are reserved for articles that caimot be satisfactorily formed in any other way, owing to complexity or small production quantities. [Pg.22]

S has been approximated for flames stabili2ed by a steady uniform flow of unbumed gas from porous metal diaphragms or other flow straighteners. However, in practice, S is usually determined less directly from the speed and area of transient flames in tubes, closed vessels, soap bubbles blown with the mixture, and, most commonly, from the shape of steady Bunsen burner flames. The observed speed of a transient flame usually differs markedly from S. For example, it can be calculated that a flame spreads from a central ignition point in an unconfined explosive mixture such as a soap bubble at a speed of (p /in which the density ratio across the flame is typically 5—10. Usually, the expansion of the burning gas imparts a considerable velocity to the unbumed mixture, and the observed speed will be the sum of this velocity and S. ... [Pg.518]

The desired air—fuel volume ratio is usually seven or more, depending on the stoichiometry. Burners of this general type with many multiple ports are common for domestic furnaces, heaters, stoves, and for industrial use. The dame stabilizing ports in such burners are often round but may be slots of various shapes to conform to the heating task. [Pg.524]

It is often desired to substitute directiy a more readily available fuel for the gas for which a premixed burner or torch and its associated feed system were designed. Satisfactory behavior with respect to dashback, blowoff, and heating capabiHty, or the local enthalpy dux to the work, generally requires reproduction as neady as possible of the maximum temperature and velocity of the burned gas, and of the shape or height of the dame cone. Often this must be done precisely, and with no changes in orifices or adjustments in the feed system. [Pg.524]

Surface combustion devices are designed for fully premixing the gaseous fuel and air and burning it on a porous radiant surface. The close coupling of the combustion process with the burner surface results in low flame temperatures and, consequently, low NO formation. Surface materials can include ceramic fibers, reticulated ceramics, and metal alloy mats. This approach allows the burner shape to be customized to match the heat transfer profile with the application. [Pg.2392]

Kegel, m. cone bevel, taper pin, skittle. Kegel-, conical, -brenner, m. cone burner, -flache, /. conical surface, -flaschei /. conical flask (as an Erlenmeyer flask). kegelfdrmig, a. cone-shaped, conical, coniform, tapered. [Pg.240]

Utilizing a forced-draft fan, the burner has a gas head arranged to mix the fuel and air in a blast tube which controls the stability and shape of the flame. Gas exits from nozzles or holes in the head and is mixed partly in the high-velocity air stream and partly allowed to exit into an area downstream of a bluff body. Behind the bluff body, a relatively quiescent zone forms which provides a means for flame stability. Many configurations exist, but the most... [Pg.375]

Nozzle mix 30kW-40MW Yes All gases 15 mbar-1.5 mbar <20 1 depends on oil turndown when dual-fuel Normally nonluminous shape depends on burner and register configuration Wide use in packaged burners of all sizes. Common in hot water and steam boilers of all sizes... [Pg.377]

PF burners and fluid beds best meet requirements for dual- and triple-fuel firing including solid fuel as one option. PF burners are particularly suitable, as no static grate exists to compromise the design. They also have a combustion geometry which is similar to gas and oil, and therefore the flame can be arranged to allow full development of flame shape and maximum radiant heat transfer surface utilization. [Pg.383]

A burner which utilises a mixture of fuel and oxidant gases and which is attached to a waste vessel (liquid trap) should be provided with a U-shaped connection between the trap and the burner chamber. The head of liquid in the connecting tube should be greater than the operating pressure of the burner if this is not achieved, mixtures of fuel and oxidant gas may be vented to the atmosphere and form an explosive mixture. The trap should be made of a material that will not shatter in the event of an explosive flash-back in the burner chamber. [Pg.803]

Figure 5.1.7a shows a side view of a lean propane flame, 10 cm in diameter, propagating downward in a top-hat flow. The flame speed is 9cm/s, below the stability threshold, and the flame is stable at all wavelengths. Figure 5.1.7b shows a near stoichiometric flame in the same burner. The flame is seen at an angle from underneath. The mixture is diluted with nitrogen gas to reduce to flame speed to the instability threshold (10.1 cm/s), so that the cells are linear in nature. The cell size here is 1.9 cm. Figure 5.1.7c shows a flame far above the instability threshold, the cell shape becomes cusped, and the cells move chaotically. [Pg.72]

For the range of flow velocities and the two equivalence ratios considered in what follows, the flames are naturally anchored on the burner lips and take a conical shape (Figure 5.2.4, CF Statio). The burner... [Pg.83]

Reverberatory furnaces melt metals in batches using a pot-shaped crucible that holds the metal over an electric heater or fuel-free burner. The flux reacts with impurities. [Pg.155]


See other pages where Shape 235 burners is mentioned: [Pg.26]    [Pg.612]    [Pg.20]    [Pg.415]    [Pg.23]    [Pg.572]    [Pg.87]    [Pg.493]    [Pg.57]    [Pg.60]    [Pg.310]    [Pg.414]    [Pg.421]    [Pg.524]    [Pg.2383]    [Pg.289]    [Pg.265]    [Pg.367]    [Pg.391]    [Pg.378]    [Pg.318]    [Pg.96]    [Pg.471]    [Pg.6]    [Pg.36]    [Pg.84]    [Pg.90]    [Pg.138]    [Pg.151]    [Pg.175]    [Pg.187]    [Pg.265]    [Pg.126]    [Pg.67]    [Pg.511]    [Pg.348]   
See also in sourсe #XX -- [ Pg.553 ]




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