SS 347 / 347H Instrumentation Tube Fittings Manufacturer, Supplier and Exporter in India
Arrotop manufactures, supplies and exports SS 347 / 347H Instrumentation Tube Fittings for refinery heaters, boiler equipment, thermal-processing systems, welded process skids and instrument lines exposed to repeated heating.
Arrotop supplies SS 347 and SS 347H connectors, elbows, tees, unions, bulkhead fittings, adapters, reducer port connectors, tube caps, plugs and ferrules. Single ferrule and double ferrule fittings are available for both imperial and metric tubing.
SS 347 is a niobium-stabilised stainless-steel grade commonly selected for welded equipment that operates through repeated heating cycles. SS 347H is the higher-carbon version and is specified where greater strength and creep resistance are required at elevated temperatures.
Arrotop supplies standard products, custom connections and replacement UNS S34700 and UNS S34709 Instrumentation Tube Fittings for OEMs, EPC contractors, refineries, power plants, maintenance teams and export buyers.
Niobium-Stabilised Fittings for Welded Hot-Service Equipment
Instrumentation tubing installed around fired heaters, boilers, reactors and thermal equipment may remain exposed to heat for long periods or pass through repeated heating and cooling cycles.
SS 347 is stabilised with niobium and is commonly specified for welded systems exposed to such conditions. The stabilisation helps the material retain resistance to intergranular corrosion after welding and during elevated-temperature service.
Arrotop supplies SS 347 Instrumentation Tube Fittings for welded hot-service equipment, including connections for:
- Pressure gauges and transmitters
- Temperature-monitoring instruments
- Hot-gas sampling systems
- Flow and differential-pressure lines
- Valve and manifold hook-ups
- Furnace and boiler control lines
- Reactor monitoring systems
- Exhaust and stack instruments
- Heated process skids
- Thermal-storage equipment
The fitting material should match the tubing grade, equipment drawing and project specification.
Available SS 347 / 347H Instrumentation Tube Fittings
Arrotop manufactures the following products in SS 347 and SS 347H:
- Male Connectors
- Female Connectors
- Union Connectors
- Male Elbows
- Female Elbows
- Union Elbows
- Male Run Tees
- Female Run Tees
- Male Branch Tees
- Female Branch Tees
- Union Tees
- Straight Unions
- Reducing Unions
- Bulkhead Male Connectors
- Bulkhead Female Connectors
- Bulkhead Unions
- Union Crosses
- Reducer Port Connectors
- NPT Male Adapters
- BSPT Couplings
- BSPP Plugs
- Tube Caps
- Tube Plugs
- Front Ferrules
- Back Ferrules
Both SS 347 single ferrule fittings and SS 347/347H double ferrule tube fittings can be supplied for new equipment, plant maintenance and repeat OEM requirements.
Buyers can send individual product enquiries or a complete fitting schedule covering several connection types and sizes.
Features of SS 347 / 347H Instrumentation Tube Fittings
- Manufactured in SS 347 / UNS S34700 / EN 1.4550 and SS 347H / UNS S34709, as required by the equipment specification.
- Niobium stabilisation makes SS 347 suitable for welded instrumentation systems exposed to repeated heating and cooling cycles.
- Maintains resistance to intergranular corrosion after welding and during elevated-temperature service.
- SS 347H has a controlled higher carbon content and is selected where greater strength and creep resistance are required at high operating temperatures.
- Commonly used for refinery-fired heaters, boiler equipment, hot-gas sampling lines, thermal-processing plants and welded process skids.
- Suitable for instrument connections exposed to intermittent heating, particularly where the project specifies a niobium-stabilised stainless-steel grade.
- Available in single ferrule and double ferrule designs for imperial and metric instrumentation tubing.
- Exact grade marking and material traceability help confirm whether the fitting is SS 347 or the higher-carbon SS 347H grade.
Technical Specifications of SS 347 / 347H Instrumentation Tube Fittings
- Product : SS 347 / 347H Instrumentation Tube Fittings
- Material Grades : Stainless Steel 347 and Stainless Steel 347H
- UNS Designations : UNS S34700 for SS 347 and UNS S34709 for SS 347H
- European Designation : EN 1.4550 for SS 347
- Material Type : Niobium-stabilised austenitic stainless steel
- Imperial Tube Sizes : 1/16 inch to 1½ inch
- Metric Tube Sizes : 1.5 mm to 38.1 mm
- Thread Types : NPT, BSPT, BSPP, SAE, UNF and Metric Threads
Applications of SS 347 / 347H Instrumentation Tube Fittings
SS 347 / 347H Instrumentation Tube Fittings are mainly used around refinery heaters, boilers, reactors, furnaces and welded process equipment exposed to repeated heating. SS 347 is commonly selected for stabilised welded systems, while SS 347H is used where higher-temperature strength is required.
Typical applications include:
- Refinery fired-heater pressure and temperature lines
- Boiler, superheater and reheater instrument connections
- Reactor vessel monitoring lines
- Hot-gas sampling systems
- Furnace pressure and burner-control tubing
- Heat exchanger gauge and transmitter hook-ups
- Petrochemical cracking-unit instrumentation
- Thermal oxidiser monitoring lines
- Exhaust and stack instrument connections
- Welded process-skid tubing
- Steam sampling and differential-pressure lines
- Valve and manifold connections near hot equipment
- High-temperature analyser panels
- Replacement fittings for existing SS 347 and SS 347H systems
Arrotop supplies SS 347 and SS 347H connectors, elbows, tees, unions, bulkhead fittings, reducers, adapters and ferrules for new equipment, shutdown maintenance and replacement requirements.
The fitting grade should match the tubing material, equipment drawing and operating conditions. Share the fitting list, tube size, thread details, grade and quantity for quotation.
SS 347H Fittings for Refinery Fired Heaters
Refinery fired heaters use instrument tubing for pressure monitoring, temperature control, burner management, fuel systems and hot-process sampling.
Where the equipment specification calls for SS 347H, Arrotop can supply:
- Fired-heater pressure connections
- Burner-control tube fittings
- Fuel and pilot-line instrument fittings
- Furnace inlet and outlet monitoring connections
- Hot-gas sampling fittings
- Temperature-transmitter hook-ups
- Differential-pressure lines
- Valve and manifold connections
- Stack and exhaust-monitoring fittings
- Replacement ferrules and adapters
SS 347H is widely associated with oil refineries, fired-heater tubes, reactor vessels, welded tubes and fittings used in elevated-temperature service.
For a quotation, share the heater drawing, fitting list, tube size, thread details, operating conditions and required material grade.
SS 347 / 347H Tube Fittings for Boiler and Steam Equipment
Boilers, superheaters and reheaters use small-bore tubing for pressure, temperature, steam sampling and equipment-monitoring connections.
Arrotop manufactures SS 347H Tube Fittings for boiler instrumentation, including:
- Boiler pressure-instrument connections
- Superheater and reheater monitoring lines
- Steam sampling fittings
- Temperature-transmitter hook-ups
- Differential-pressure connections
- Boiler casing instrument lines
- Valve and manifold tubing
- Vent and drain instrument fittings
- Custom adapters for boiler equipment
- Maintenance replacement fittings
UNS S34709 is used for superheater and reheater tubing in coal-fired, biomass and other boiler systems. The fitting grade and pressure rating should still follow the equipment design and complete tubing specification.
Replacement SS 347 / 347H Fittings for Existing Equipment
Older refineries, boiler plants, imported machinery and custom thermal skids may use fittings that do not match present catalogue dimensions.
The requirement may involve:
- Non-standard tube sizes
- Special NPT or BSP threads
- Longer connector bodies
- Extended male threads
- Metric-to-imperial connections
- Reducing tube ends
- Custom bulkhead lengths
- Gauge and transmitter adapters
- Weld-end connectors
- Old OEM part numbers
- Discontinued fitting designs
Arrotop manufactures custom and replacement SS 347 / 347H Instrumentation Tube Fittings from equipment drawings, dimensional sketches or unused samples.
For replacement enquiries, share the tube OD, thread size, overall dimensions, material grade and required quantity. A drawing or physical sample is recommended when the internal ferrule arrangement or thread form is unknown.
SS 347H Fitting Packages for Heater and Boiler Shutdowns
Planned shutdown work normally requires several fitting types for different equipment areas. Maintenance teams may need connectors, elbows, tees, unions, ferrules, reducers and adapters supplied together against one bill of materials.
Arrotop supplies SS 347H fitting packages for refinery shutdowns, fired-heater maintenance and boiler overhauls.
A shutdown package may include:
- Male and female connectors
- Elbows, run tees and branch tees
- Straight and reducing unions
- Bulkhead fittings
- Front and back ferrules
- NPT and BSP adapters
- Reducer port connectors
- Tube caps and plugs
- Drawing-based replacement fittings
- Material certificates when requested
Share the fitting schedule, SS 347 or SS 347H grade, tube size, threads, quantities, inspection requirements and delivery schedule for quotation.
SS 347 / 347H Tube Sizes and Thread Options
SS 347 and SS 347H Instrumentation Tube Fittings can be manufactured for imperial and metric tubing, subject to the product design.
Available options include:
- Imperial tube sizes from 1/16 inch to 1½ inch
- Metric tube sizes from 1.5 mm to 38.1 mm
- Tube-to-tube connections
- Tube-to-male thread connections
- Tube-to-female-thread connections
- Equal and reducing connections
- Bulkhead connections
- NPT threads
- BSPT threads
- BSPP threads
- SAE and UNF threads
- Metric threads
- Mixed-thread adapters
- Special connections made from drawings
The working pressure depends on the fitting design, tube OD, wall thickness, tube condition, operating temperature and end connection. One common pressure rating should not be applied to every size and configuration.
SS 347 vs SS 321 Instrumentation Tube Fittings for Repeated Heating
SS 347 and SS 321 are stabilised stainless-steel grades used in welded equipment exposed to heat. The main difference is the stabilising element: SS 321 uses titanium, while SS 347 uses niobium.
SS 347 is often specified for welded instrument lines exposed to repeated or intermittent heating. It offers improved resistance to intergranular corrosion compared with SS 321 in these conditions and maintains useful mechanical properties at elevated temperatures.
For refinery heaters, boiler equipment, thermal-processing systems and hot-service process skids, the choice between SS 347 and SS 321 Instrumentation Tube Fittings should follow the approved drawing, tubing grade and project material specification.
Arrotop supplies SS 347 Compression Tube Fittings for repeated heating cycles, including connectors, elbows, tees, unions, bulkhead fittings, adapters and ferrules. Replacement fittings can also be manufactured against drawings, dimensions or existing samples.
SS 347 / 347H Tube Fittings for Steam Crackers, Reformers and Chemical Furnaces
Steam crackers, reformers and chemical furnaces use instrument tubing for pressure monitoring, temperature control, hot-gas sampling, burner management and flow measurement. Where the equipment specification calls for SS 347 or SS 347H, Arrotop can supply the required instrumentation fittings.
The range includes:
- Furnace pressure-line fittings
- Burner-control tube connections
- Hot-gas sampling fittings
- Temperature-transmitter hook-ups
- Steam and process monitoring connections
- Differential-pressure instrument lines
- Valve and manifold fittings
- Furnace inlet and outlet connections
- Exhaust and stack analyser fittings
- Custom reducers and thread adapters
SS 347/347H is used in high-temperature furnaces and refinery service, including refinery furnace tubing and chemical-furnace equipment. The grade family is also supplied for superheater and reheater applications.
Arrotop supplies SS 347H Compression Fittings for steam crackers, steam reformers and chemical furnace instrument lines in standard and custom configurations. Share the fitting schedule, tube size, thread details, grade and quantity for quotation.
Custom SS 347H Fittings for Boiler, Heater and Furnace Manufacturers
Boiler, heater and furnace manufacturers often require fittings that match their equipment drawings rather than standard catalogue dimensions. Requirements may include special body lengths, extended threads, reducing connections, mixed thread standards or repeat supply against an OEM part number.
Arrotop manufactures custom SS 347H Instrumentation Tube Fittings for boiler, heater and furnace manufacturers, including:
- Extended male and female connectors
- Custom bulkhead fittings
- NPT-to-BSP adapters
- Metric-to-imperial connections
- Special reducing unions
- Gauge and transmitter adapters
- Weld-end connectors
- Long-thread fittings
- Custom reducer port connectors
- Drawing-based elbows and tees
- Repeat fittings carrying OEM part references
- Replacement fittings for discontinued equipment
SS 347H, identified as UNS S34709, is used for boiler superheater and reheater tubing as well as other high-temperature equipment.
For a quotation, send the equipment drawing, fitting dimensions, tube OD, wall thickness, thread standard, material grade, quantity and certificate requirements. Arrotop supplies small production quantities as well as repeat orders for OEM equipment.
Request a Quote for SS 347 / 347H Instrumentation Tube Fittings.
Arrotop supplies SS 347 and SS 347H Instrumentation Tube Fittings for refinery fired heaters, boiler systems, reactor equipment, welded process skids, thermal plants and hot-service instrument lines.
For a quotation, share the required fitting type, SS 347 or SS 347H grade, tube OD and wall thickness, thread type, operating pressure, temperature, quantity, drawing or sample and certificate requirements. Arrotop manufactures and exports standard, custom and replacement UNS S34700 and UNS S34709 ferrule tube fittings from Mumbai, India, for domestic and international requirements.