Thin-walled ferrules for the inlet and outlet of heat exchanger and boiler tubes, where heat and particles meet the tube end.
The gas is hottest and the particles hit hardest at the tube inlet.
That is where the ferrule goes.
Boiler tube ferrules protect the tube end, the tube-to-tubesheet weld and the first inches of the tube against the two things that attack them most: the heat of the process gas entering the tube and erosion by the particles it carries. The ferrule takes that load in place of the tube and is replaced when it is worn. Blasch casts boiler tube ferrules in OXYTRON oxide bonded silicon carbide, with thin walls, tapered inlets and tight tolerances, for the inlet and outlet ends of heat exchanger and boiler tubes.
At the tube inlet the gas changes direction and speeds up. Particles strike the wall there, and the gas still carries its full heat. Erosion that reaches the tube-to-tubesheet weld lets gas leak past the tubesheet, and the usual repair is to cut the tube out and replace it.
A ferrule moves that damage onto a replaceable part. It lines the first inches of the tube, covers the weld and gives the gas a tapered entry.
Every tube end wears somewhere; a ferrule decides that it wears on a part you can pull out, not on a weld you have to cut.
OXYTRON is an oxide bonded silicon carbide that Blasch uses for parts that face heat and particles at the same time. More on oxide bonded silicon carbide.
Holds up to the particle erosion that wears through metallic inserts at the tube inlet.
Made for high temperature service, so it carries the heat of the gas where the tube end would otherwise see it.
Cast with thin walls and tight tolerances, so the ferrule narrows the tube as little as possible.
Ferrules can be pulled for tube cleaning or left in place, depending on how the exchanger is serviced.
Many inquiries for tube end protection start with the word coating. The difference matters for how long the protection lasts.
Heat exchangers and boilers in power generation and heavy industry, where the gas carries ash or dust into the tubes. For tubular air preheaters, the matching part is the air heater insert. Where the temperature is moderate and the gas is clean, alloy metal ferrules may be enough.
Each ferrule is designed to the tube it goes into: outside and inside diameter, wall thickness, the length that should be protected and the shape of the inlet. The dimensions are enough, a drawing is not required.
It is the same kind of part. In air heaters and heat exchangers it is often called an insert, in boilers a ferrule.
Both. Ferrules can protect the inlet and the outlet end of the tube, depending on where the gas does the damage.
No. Blasch does not coat or spray. The ferrule is a cast silicon carbide part with its own wall, fitted into the tube end.
Tube dimensions, gas temperature, the kind of dust or ash in the gas and how the exchanger is cleaned. No drawing is needed.
Send the tube size, the gas temperature and what the gas carries. A Blasch engineer designs the ferrule for your exchanger.
