ASTM E84 Steiner Tunnel Furnace Chamber For Surface Burning Of Building Materials

ASTM E84 Steiner Tunnel Furnace chamber for Surface Burning Characteristics of Building Materials

Design referenced to the below standards

ASTM E84: Standard Test Method for Surface Burning Characteristics of Building Materials.

Steiner Tunnel Furnace Chamber Design Proposal

2.1 Summary

This technical solution for Steiner Tunnel Furnace Chamber is based on the integration of instrumentation and electricity, and uses OMRON's advanced multi-function control system to combine ignition sequence, combustion safety, electrical interlocking, automatic temperature control, manual adjustment, monitoring alarm, and data acquisition / communication into one. The furnace temperature and pressure control system uses the control system composed of OMRON controller + Advantech + Visual Basic software for automatic control and online monitoring. The upper computer Advantech operation station operates and monitors the necessary process parameters of the furnace. It has data storage, inspection and printing. , And other functions. At the same time, according to the requirements of UL910 / NFPA262 standards, a dedicated combustion test room can be set up for combustion test, This combustion test room effectively isolates the Steiner horizontal tunnel furnace,Install the smoke density measuring end in a dark room,Avoid interference from external light；Burn test area, adopt independent design method,according to the standard requirement, should provide free airflow. Therefore, during the entire test, keep the room under controlled air pressure of 0-12 Pa (0-0.05 inch water volume) higher than the surrounding air pressure.,The temperature is maintained at 18.3 ° C-26.7 ° C (65 ° F-80 ° F) and a relative humidity of 45-60%.

2.1.1 Design conditions

 Furnace type: Steiner horizontal tunnel furnace

 Furnace main dimensions: Furnace size 7620mm * 451mm * 305mm

 Number of furnace covers: Steiner horizontal tunnel furnace: 1 furnace cover

 Furnace working temperature: up to 600 ℃ (flue gas temperature)

 Fuel: Methane with a purity of at least 95%

 Fuel calorific value: 3500btu / lb

 Fuel pressure: 0.4-0.5MPa

 Burner model: 3/4 inch U-shaped double burner

 Exhaust temperature of flue pipe: <250 ° C, usually the flue gas temperature is controlled within 200 ° C.

 Test method of the tested object: Horizontal component furnace-furnace ceiling hoisting

Design conditions 15KVA, 380V/220V, 3 phases. Notes: Voltage can be customized.

2.1.2 Structural parameters

1.  Furnace structure: refractory brick + SUS304 stainless steel plate
2.  Furnace bottom structure: refractory brick 229mm x 114.5mm x 64mm
3.  Type and quantity of burner: 1 3 / 4-inch U-shaped double burner.
4.  Smoke exhaust method: mechanical smoke exhaust + cold air mixing on the back wall
5. Furnace door opening method: Horizontal component furnace-hoist ceiling hoisting and translation (customer built)
6. Furnace diagram

2.1.4 Purpose:

Steiner Tunnel Furnace Chamber is used for ASTM E84 test of building materials.

2.1.5 Design principles

Adopt the principles of advanced technology, reliability, safety, and economic rationality

2.2 Furnace structure

2.2.1 Furnace Shell

The furnace steel structure is composed of square tube / rectangular tube end, side upright and furnace body steel plate. After being welded with high strength, it forms a solid whole, which can be used without deformation for a long time.

Furnace body steel plate:SUS304,δ=3mm

Furnace frame:Q235-A ,Square tube / rectangular tube

Furnace transverse bars:Q235-A ,Square tube/ rectangular tube

Window:Quartz glass and tempered glass double layer combination,δ=3mm,70mm±6mm×280mm±38mm

The shutter provides a 74~78mmopening high from the floor level of the chamber. The shutter can be adjusted.

The burner is located in 1372±10mm from the air inlet. air velocity port is 381±5mm from the air inlet.

locations of thermocouples

1. A 18 awg thermocouple is located in the 7000±10mm from burner port( exposed on the air);
2. A 18 awg thermocouple is located in the 3960±10mm from burner port(embedded below the floor);

A 18 awg thermocouple is located in the 7090±10mm from burner port (embedded below the floor).

The ledges are manufactured from Q235-A steel, with water cooled device.

2.2.2 Furnace Resistance materials

The test furnace masonry is consisted of refractory bricks, At the same time, in order to provide the air turbulence required during the combustion process,Obtained by placing six 229mm long x 114.5mm wide x 64mm thick heat-resistant refractory bricks(Long vertical line of the wall and 114.5mm long parallel line). According to the measured burner centerline to the refractory brick centerline,Refractory bricks near the window (without obstructing the windows) 1.98m±152mm,3.96m±152mm and 5.79±152mm,the distance of another side is 1.37m±152mm,2.90m±152mm and 4.88m±152mm.

The highest Temperature resistance: 1427℃ (2600℉)

Bulk Density: 0.77±0.046g/cm3

Thermal conductivity at average temperature:

260℃(500℉) 0.23W/m·℃

538℃(1000℉) 0.27 W/m·℃

815℃(1500℉) 0.32 W/m·℃

1093℃(1500℉) 0.37 W/m·℃

2.2.3 Furnace door and Pressing mechanism

Operation Furnace door above the furnace body, as a sealing device for the furnace body. Composed of metal and inorganic insulators, Insulators composed of inorganic insulators, 51mm ± 6mm thick inorganic insulator material

Horizontal furnace door is welded by section steel, use self-weight vertical lifting method to compact, to observe the condition of the furnace, observation windows installed on both sides of the furnace wall, to get an effective seal, an effective water seal acts as a seal between the furnace door and the furnace body, Using tap water as the circulating water source can not only provide a seal for the quality inspection of the furnace body and the furnace door, but also take away the heat during the combustion test and effectively protect the furnace body.

The lab should provide the crane to lift the lid.

Max. Effective use temperature up to 1050℃；

Density: 335±5kg/m3;

Thermal Conductivity: 0.085W/mK@400 ℃

Dimension 7620±50mm*451±5mm*305±5mm