High-temperature fasteners for Furnaces & Heat Treatment.
Hot-zone oxidation and loaded-joint creep are different problems. Specify metal temperature, atmosphere and duty cycle before choosing the fastener alloy.
Which fasteners fit your furnace and heat-treatment applications?
BYBOLT supplies Inconel 601 hex bolts for burner and hot-zone attachments, Incoloy 800H stud bolts for loaded hot joints, and 310S long-shank hex bolts for furnace fixtures. Inconel 601 hex flange bolts retain shields and brackets with drawing-defined expansion clearance. We match the grip length, alloy condition and mating parts to the furnace atmosphere and metal temperature.
Fasteners for furnace equipment & fixtures.
Quench racks & baskets
RA330 tie rods and clevis pins combine oxidation resistance with ductility for thermally cycled quench racks. Match their sections and clearances to the basket load and cooling cycle.
RA330 long-shank tie rodsRelated material guides
Connection requirements
- Tie-rod length and thread engagement
- Clevis pin diameter and retaining method
- Basket frame hole clearance
Carburizing & stack fixtures
On furnace fixture blocks and stack accessories, Nimonic 75 socket screws provide compact, heat-resistant fastenings. Recessed heads can keep the drive out of the working envelope around the fixture. Their moderate-strength character suits locating and retaining duties where oxidation is the primary material concern.
Nimonic 75 Socket Head Cap ScrewsRelated material guides
Connection requirements
- Tapped-hole size, thread form, and effective engagement depth
- Head diameter, head height, and counterbore clearance required
- Temperature range, cycling duty, and heat-number certification
Retort & muffle covers
Retort and muffle cover bolts face repeated exposure to hot oxidizing atmospheres. Inconel 601's aluminium-assisted oxidation resistance makes it useful for these furnace fastening points. Hex heads provide direct wrench access when the cover is opened, while the cover design accommodates its thermal expansion.
Inconel 601 Hex BoltsRelated material guides
Connection requirements
- Cover joint thickness, gasket type, and required preload
- Bolt diameter, grip length, and nut/washer stack-up at installed position
- Temperature range, cycling duty, and heat-number certification
Radiant tubes & circulation fans
Around radiant-tube flanges and furnace circulation hardware, 601 studs provide fixed fastening points in a hot oxidizing atmosphere. The nuts can be removed for component servicing while the studs remain installed. Material oxidation resistance is particularly relevant where exposed thread ends repeatedly see the furnace atmosphere.
Inconel 601 Stud BoltsRelated material guides
Connection requirements
- Housing joint thickness, and required preload
- Stud diameter, overall length, and nut engagement at each end
- Temperature range, vibration duty, and heat-number certification
Burner mounts & nozzles
Nimonic 75 socket screws fit small burner covers and accessory brackets between closely packed fuel-air components. They provide oxidation resistance for moderate-load attachments, with access along the screw axis during servicing.
Nimonic 75 Socket Head Cap ScrewsRelated material guides
Connection requirements
- Tapped-hole size, thread form, and effective engagement depth
- Head diameter, head height, and socket depth for drive engagement
- Temperature range, cycling duty, and heat-number certification
Heat shields & furnace linings
Nimonic 75 socket screws suit compact shield-retainer blocks where a tool can approach from above but not around the head. The alloy supplies oxidation resistance for moderate-load hot attachments. Shield expansion is accommodated in the retaining arrangement, leaving the screw to secure the block rather than restrain the whole sheet.
Nimonic 75 Socket Head Cap ScrewsRelated material guides
Connection requirements
- Tapped-hole size, thread form, and effective engagement depth
- Head diameter, head height, and socket depth for drive engagement
- Temperature range, cycling duty, and heat-number certification
Atmosphere, Creep Load, Thermal Cycling.
310S offers a cost-effective option for lightly loaded fixtures in oxidizing furnaces. RA330 is used for carburizing and nitriding equipment, while 601 emphasizes oxidation and scale resistance. Match the fastener to the actual furnace gas and metal temperature.
What to specify
- Carbon potential
- Atmosphere dew point
- Operating temperature range
800H and 800HT are options for supports and cover studs carrying sustained hot loads. Their creep capability depends on temperature, stress, grain size and heat treatment; use the grade-specific data rather than treating 800HT as an automatic load upgrade.
What to specify
- Sustained load duration
- Creep strain allowance
- Support span length
RA330 offers ductility for thermally cycled racks; 601 resists scale loss during repeated heating, and 310S suits milder cycling. Slots and stand-off sleeves provide movement clearance, while section thickness and cooling rate govern quench stresses.
What to specify
- Thermal cycle frequency
- Quench medium severity
- Expansion sleeve travel allowance
Compare furnace fastener alloys.
| Material grade | Mechanical Duty / Focus | Environment | Relative cost | Popular fastener forms |
|---|---|---|---|---|
| Inconel 601UNS N06601Oxidation resistance |
| Oxidizing furnace atmospheres and repeated heating cycles | $$$ |  Hex bolts |
| Incoloy 800HUNS N08810Creep resistance |
| Hot furnace atmospheres with sustained mechanical loading | $$$ |  Stud bolts |
| 310S stainless steelUNS S31008Cost-effective |
| Oxidizing hot-air zones and furnace fixtures | $$ |  Long-shank bolts |
Budget guide: $ lower · $$ moderate · $$$ higher · $$$$ premium. Relative raw-material bands; dimensions, quantity, processing and inspection determine the finished-fastener quote.
Material & cost references
- Special Metals — INCONEL alloy 601
- Special Metals — INCOLOY alloys 800H and 800HT
- Outokumpu — Therma 310S and heat-resistant stainless steels
- Nickel and specialty-alloy round-bar price comparison
- Stainless-steel supplier price ranges
- 800H round-bar supplier price range
- Alloy 20 round-bar supplier price range
Duty bars are a qualitative BYBOLT selection summary of the producer references: two segments indicate good capability; three highlight a key strength. They are not measured performance ratios. Cyclic oxidation describes oxide-scale resistance during heating and cooling, not thermal-fatigue life; 310S is intended for mildly cyclic exposure. Creep selection depends on temperature, duration and material condition.
Cost bands group overlapping published supplier ranges for initial budgeting; they are not live BYBOLT prices. Specify the exact UNS and final condition on the order.
Furnace bolts, studs & fixture fasteners.
Inconel 601 hex bolts
Resist oxidation and scaling on trays and fixtures during repeated high-temperature furnace cycles.
Incoloy 800H stud bolts
Resist creep and elongation under sustained loads in hot retort-cover joints.
310S long-shank hex bolts
Secure spaced heat shields in annealing furnaces; a cost-effective choice for lightly loaded joints requiring oxidation resistance.
Inconel 601 hex flange bolts
Distribute clamping load across shields and brackets while resisting oxidation near furnace burners.
Furnace mounting kits.
Bring the bolts, nuts, washers and spacers for each furnace assembly into one order, with materials and dimensions matched to its operating conditions.
Furnace fastener traceability & inspection.
EN 10204 3.1 MTC, heat traceability and mechanical test results with each shipment. Add the tests your equipment specification requires.
Material identity
Match the ordered grade and material heat to the certificate, part identification and packing list.
Final condition
Link the specified processing condition and mechanical results to the finished batch; keep separate heat-treatment batches identifiable.
Drawing dimensions
Fixture revision, original dimensions and spare quantities.
Hot-service evidence
Define any creep or relaxation requirement by temperature, duration, stress and acceptance criteria.
Before you order furnace fasteners.
Send the drawing and the service details for your connection. We can quote the specified parts, finish and inspection package together.
Get a QuoteWhich temperature should I put on the enquiry?
State the fastener’s design or measured metal temperature, plus the furnace setpoint for context. Add peak excursions, dwell time and the heating and cooling cycle.
Can you reproduce a worn fixture bolt?
Yes. Send the original drawing or mark the original dimensions separately from wear, scale and distortion on the sample. Include the required material condition and the fixture service cycle.
Can 310S replace 800H or 601?
We can quote a drawing-approved alternative once the atmosphere, load and service duration are defined. Compare the finished-part requirements and hot-service evidence as well as the material price.
Send your drawing
or parts list.
Upload the drawing or BOM with its revision. We quote the material, dimensions, quantities and inspection requirements for your equipment.
Fixture or retort drawing, metal temperature, atmosphere, load, dwell/cycles, material condition and quantity…
