Threaded Black Fittings
Threaded black fittings are pipe fittings made of malleable cast iron without a galvanized coating, screwed directly onto black steel pipes. Produced to TS EN 10242 design symbol A, they provide a reliable threaded joint in lines operating under heat and pressure.
Central heating and boiler room installations, indoor natural gas lines, compressed air and fire lines are the main uses of black malleable fittings. From elbows to crosses and from sockets to taper seat unions, 14 fitting types are supplied from a single source in sizes from 1/8″ to 4″.
Main Applications
- Central heating, radiator and boiler room installations
- Indoor natural gas and LPG lines (in projects compliant with regulations)
- Compressed air distribution and compressor lines
- Small-bore connections in steam and condensate lines
- Threaded black pipe connections in fire-fighting lines
- Cooling water and closed-loop process lines
- Fuel oil and lubricant transfer lines
- Machine, workbench and equipment connections
Technical Data
| Product standard | TS EN 10242, design symbol A (manufacturer information) |
|---|---|
| Material | Blackheart malleable cast iron B 350-10 (sales sheet information) |
| Surface | Black, without galvanized coating |
| Thread standard | ISO 7-1: R taper male thread, Rp parallel female thread |
| Size range | 1/8″ – 4″ (product range; varies by fitting type) |
| Reducing fittings | Up to 4″ × 3″ reducers and 3″ × 2″ reducing tees (product range) |
| Permissible pressure | 25 bar, −20 … +120 °C (EN 10242, design A) |
| Pressure at high temperature | 20 bar, up to +300 °C (EN 10242, design A) |
| Leak test | At least 5 bar air or 20 bar water (sales sheet information) |
| Union seat | Taper, metal-to-metal (taper seat unions and swivel unions) |
| Fitting types | Elbow, 45° elbow, street elbow, tee, reducing tee, cross, socket, reducing socket, reducer, nipple, plug, taper seat union, swivel union, crossover |
| Installation | Screwed, no welding; with thread sealing tape, hemp or anaerobic sealant |
Material Options
| Part | Elbows, tees, crosses, sockets, reducers | Taper seat unions and swivel unions | Nipples and plugs |
|---|---|---|---|
| Body | Blackheart malleable cast iron B 350-10 | Blackheart malleable cast iron B 350-10 | Blackheart malleable cast iron B 350-10 (depending on model) |
| Nut | None | Malleable cast iron, hexagonal | None |
| Surface | Black, non-galvanized | Black, non-galvanized | Black, non-galvanized |
| Thread | ISO 7-1 Rp female thread (one end R male thread on street elbows) | ISO 7-1 Rp female / R male thread | ISO 7-1 R male thread (nipple), Rp female thread (female plug) |
| Sealing | Thread sealing material | Taper metal-to-metal seat, no gasket required | Thread sealing material |
Which material? Black malleable iron is sufficient for closed, low-oxygen circuits such as boiler, natural gas and compressed air lines. Galvanized fittings are preferred for drinking water and lines that constantly take in fresh water, and stainless threaded fittings for corrosive media.
Advantages
High Temperature Resistance
- Usable up to +300 °C at 20 bar
- Suitable for boiler and steam outlets
Fast Weld-Free Installation
- Screwed on with a wrench, no hot work required
- Shorter labour time in gas and heating lines
Matches Black Pipe
- Same surface as black steel pipe, finished by painting
- No appearance issues from coating differences
Wide Fitting Selection
- 14 types, from 1/8″ to 4″
- Reducing fittings reduce the need for extra adapters
Detachable Union Joint
- Taper seat and swivel unions let pumps, valves and meters be removed easily
Construction and Design Features
- TS EN 10242 design symbol A; pressure-temperature ratings follow the standard’s table
- Black cast surface that is not hot-dip galvanized; paint and insulation can be applied directly
- Street elbow with one female and one male end; changes direction without an extra nipple
- Taper seat union with two-piece body and hexagonal nut, seating without a gasket
- Reducing tees and reducers make the size transition in a single piece
Send the fitting type, size (both sizes for reducers) and quantity; we will let you know the suitable black malleable fittings in stock right away.
How to Choose?
- Determine the line size and threadMeasure the pipe size in inches and the thread type of the connected equipment (R male / Rp female).
- Check pressure and temperatureCompare the limits of 25 bar up to +120 °C and 20 bar at +300 °C with the operating values of the line.
- Confirm the surface for the mediumChoose black fittings for closed heating, gas and air lines; galvanized fittings for drinking water.
- Plan the points to be dismantledUse taper seat unions or swivel unions at pump, valve and meter connections.
Complementary Products
Why ORFA?
Types of Threaded Black Fittings
Threaded Black Tees
Threaded black tees are equal-size fittings used to split flow in three directions on threaded black steel pipelines.
Details →
Black 45° Elbows
Black 45° elbows are fittings used to change direction by 45 degrees on threaded black steel pipelines.
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Black Pipe Crossover Bends
Black pipe crossover bends are curved fittings used to pass over another pipe on threaded black steel lines.
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Black Unions
Black unions are fittings that join two threaded black steel pipes in a way that can be taken apart again.
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Black Elbows
Black elbows are fittings used to change direction by 90 degrees on threaded black steel pipelines.
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Black Reducing Tees
Black reducing tees are fittings used to take a smaller branch off the main run on threaded black steel lines.
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Black Conical Unions
Black conical unions provide a tight, removable connection on threaded black steel pipes through a conical seat.
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Black Plugs and Caps
Black plugs and caps are used to close the ends of threaded black steel pipes and fittings.
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Black Crosses
Black crosses are fittings that split flow in four directions on threaded black steel pipelines.
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Black Street Elbows
Black street elbows have one female and one male threaded end and change direction on black steel lines without an extra nipple.
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Black Reducing Sockets
Black reducing sockets are female threaded fittings that join two black steel pipes of different sizes.
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Black Sockets
Black sockets are female threaded fittings that join two black steel pipes of the same size in a straight line.
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Black Nipples
Black nipples are short black steel pieces with male threads on both ends, used to connect two female threaded fittings.
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Black Reducing Bushes
Black reducing bushes are fittings with male and female threads used to change pipe size on threaded black steel lines.
Details →Other Threaded Fittings
Galvanized Fittings
Galvanized fittings are zinc coated threaded fittings that resist corrosion, used in water and fire protection installations.
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Stainless Steel Threaded Fittings
Stainless steel threaded fittings provide corrosion resistant threaded joints in food, chemical and process lines.
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Brass Fittings
Brass fittings are corrosion resistant threaded fittings used in water, heating and gas installations.
Details →Get a quote for your project
Our sales team will prepare the best solution for your needs.