MP159 Set Screws
RAYCHIN SPECIALTY METALS FASTENERS: BOLTS, NUTS, SCREWS, WASHERS, STUDS, THREADED RODS, U-BOLT, J-BOLTS
STANDARD AND CUSTOMIZED, SMALL BATCH AND LARGE BATCH, IMPERIAL AND METRIC
Ultra-strength combined with extreme temperature capabilities
Extreme high strength properties up to 275 ksi ultimate tensile.
Maintains superior strength to 1100°F.
Key Benefits
High ultimate tensile strength of 275 ksi and yield strength of 265 ksi (Cold Worked and Age Hardened) combined with excellent ductility and toughness
Similar corrosion resistance compared to MP35N which is usable in mineral acids, hydrogen sulfide, seawater and salt spray environments.
Excellent fatigue resistance and creep strength at elevated temperatures.
Excellent resistance to crevice corrosion, stress corrosion cracking and hydrogen embrittlement.
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RAYCHIN LIMITED
MP159 Set Screws · Grub Screws · Cup / Cone / Flat / Dog Point · Inch & Metric · AMS 5841 / 5842 / 5843MP159 Set Screws: Ultra-High Strength Cobalt-Nickel Alloy Grub Screws for Extreme Temperature Applications
RAYCHIN LIMITED is a leading manufacturer of MP159 Set Screws – precision headless fasteners engineered from cobalt-nickel-chromium-molybdenum multiphase superalloy, delivering the ultimate combination of ultra-high strength, exceptional corrosion resistance, and reliable performance in the most demanding high-temperature applications. Set screws (also known as grub screws) have no protruding head and are fully threaded, with a drive socket at one end and various point styles to suit different applications. They are used to secure an object within or against another object, typically to prevent relative motion between rotating parts such as gears and shafts . Through precise cold working (48% reduction) and age hardening, MP159 achieves ultimate tensile strength up to 275 ksi (1895 MPa) while maintaining excellent ductility and toughness . Developed specifically for higher operating temperatures, MP159 can perform in applications up to 593°C (1100°F), surpassing the capabilities of MP35N by 300°F . Our portfolio includes all standard and custom configurations manufactured to NAS, AN, MS, ANSI, ASTM, ASME, SAE, API, NACE, ISO, DIN and KS standards, including ASME B18.3 (inch series) and ISO 4026-4029 (metric series). Whether you require MP159 set screws for advanced gas turbine engines, downhole drilling tools, or medical devices, RAYCHIN delivers precision, quality, and full traceability. All mechanical properties are presented in MPa and ksi (kilopound per square inch).
MP159 Set Screws – Point Styles & Configurations
Cup Point Set Screws
MP159 cup point set screws feature a cup-shaped indentation on one end. This is the most commonly used point style, designed for quick, semi-permanent or permanent applications where the sharp edge of the cup point can bite into the mating surface to provide maximum resistance to loosening . Ideal for general shaft and gear retention.
Cone Point Set Screws
MP159 cone point set screws have a sharp, conical point (like an ice cream cone) that delivers the strongest clamping force due to deep penetration into the mating shaft. They are typically used for permanent assembly applications where maximum holding power is required and shaft deformation is acceptable .
Flat Point Set Screws
MP159 flat point set screws have a flat, smooth bearing surface. This economical style is used when components need to be frequently adjusted or repositioned, as they minimize shaft deformation and allow for repeated removal and reinstallation without damaging the mating surface .
Dog Point Set Screws
MP159 dog point set screws feature a cylindrical projection (dog) that extends beyond the thread. The dog fits into a mating hole in the shaft, providing positive axial location and preventing movement under high shear loads. Available in extended and half-dog point configurations.
Drive Types & Socket Configurations
MP159 set screws are available with various drive types including hex socket (Allen), slotted, and tamper-resistant security drives. Hex socket is the most common for high-torque applications. Precision-formed sockets ensure consistent engagement and minimize cam-out during installation.
Custom & Non-Standard Set Screws
Need a special point geometry, non-standard length, proprietary drive, or unique thread form? RAYCHIN engineers design and produce custom MP159 set screws to your exact specifications – any condition (annealed, cold worked, aged), with full material traceability. Prototype to production volumes supported.
Critical Applications of MP159 Set Screws
Aerospace & Defense
MP159 set screws are extensively used in advanced gas turbine engines, jet propulsion systems, rocket boosters, and actuation systems . They secure critical components such as gears, pulleys, and bearings onto rotating shafts. The alloy's exceptional high-temperature strength (up to 1100°F) ensures reliable performance in turbine sections. Non-magnetic properties essential for sensitive instrumentation .
Oil & Gas / Downhole Tools
MP159 set screws qualified per NACE MR0175 for downhole drilling tools, MWD/LWD equipment, wellhead connectors, and subsea actuators . Resist sulfide stress cracking (SSC) and pitting in H₂S/CO₂ environments at elevated pressures and temperatures . Cup and cone point styles provide positive retention of components in high-vibration downhole environments .
Power Generation
MP159 set screws in gas turbines, steam turbines, and nuclear reactor internals provide reliable fastening of control linkages, sensor mounts, and balance weights . Maintain clamping force after thousands of thermal cycles from cryogenic to 1100°F without relaxation . Excellent creep strength at elevated temperatures ensures long-term reliability.
Medical & Surgical Implants
MP159 set screws used in surgical instruments, orthopedic external fixators, and prosthetic devices . Full biocompatibility, excellent fatigue resistance for long-term cyclic loading, and non-magnetic for MRI compatibility. Set screws provide precise adjustment and locking mechanisms in modular implant systems .
Marine & Subsea
MP159 set screws in seawater pump couplings, subsea connector assemblies, ROV systems, and offshore platform components resist pitting and crevice corrosion in saltwater . Virtually immune to crevice corrosion, stress corrosion cracking, and pitting even at the highest strength levels .
Chemical Processing
MP159 set screws in high-pressure reactor flanges, pump casings, and valve bonnets resist most mineral acids, hydrogen sulfide, and chloride solutions . Provide secure retention of internal components in aggressive chemical environments .
International Standards & Global Designations – MP159 Set Screws
RAYCHIN LIMITED manufactures MP159 set screws from vacuum induction melted (VIM) and vacuum arc remelted (VAR) material conforming to the most widely used national and international specifications. All material is traceable to the mill.
Chemical Composition (Weight %) – MP159 Alloy for Set Screws
Our MP159 set screws are produced from vacuum induction melted (VIM) and vacuum arc remelted (VAR) material conforming to the following limits per AMS and industry standards.
Metallurgical note: MP159 is a multiphase cobalt-nickel-chromium-molybdenum alloy strengthened through a unique combination of solid solution strengthening, cold work hardening (typically 48% reduction), and age hardening via precipitation of γ' phase [Ni₃(Al, Ti, Nb)] and ε phase formation . The alloy maintains excellent ductility even at high cold reduction levels, enabling production of high-strength set screws with precision-formed points and rolled threads. It remains essentially non-magnetic (permeability ~1.00265 μ) even after extensive cold working, critical for medical and directional drilling applications . MP159 was developed specifically for higher operating temperatures compared to MP35N, with service capability up to 1100°F (593°C) . Heat treatment per AMS 5843: solution anneal 1900-1925°F (1040-1055°C), 48% cold work, age 1200-1250°F (650-675°C) for 4-4.5 hours . The high chromium (19%) and molybdenum (7%) content promotes formation of a dense Cr₂O₃ protective film, providing exceptional hot corrosion resistance .
Complete Mechanical & Physical Properties – MP159 Set Screws (MPa / ksi)
MP159 set screws are supplied in various conditions per AMS specifications. Data represent typical values based on AMS and industry standards. ksi values (kilopound per square inch) are provided alongside MPa.
Mechanical Properties by Condition – MP159 Set Screws
Physical Properties – MP159 Alloy
High‑Temperature Performance of MP159 Set Screws
MP159 alloy was developed specifically to meet the need for a fastener alloy that could perform under the higher operating temperatures required for turbine engines and other high performance motors . It has advantages similar to MP35N but can perform in applications up to 593°C (1100°F) and is suitable for short term use at even higher temperatures . The high chromium content (19%) promotes formation of a dense, protective Cr₂O₃ film that provides excellent hot corrosion resistance in aggressive environments .
Elevated Temperature Capabilities
High-Temperature Comparison – MP159 vs. MP35N
Note: MP159 fills the critical gap between MP35N and higher-temperature alloys like Inconel 718, offering superior strength up to 1100°F with excellent corrosion resistance .
Exceptional Corrosion Resistance of MP159 Set Screws
MP159 alloy offers outstanding corrosion resistance across a wide range of aggressive environments, making it suitable for the most demanding applications including medical implants, downhole tools, marine equipment, and chemical processing .
- General Corrosion Resistance: Similar corrosion resistance to MP35N, excellent resistance to most mineral acids, hydrogen sulfide, seawater and salt spray environments .
- Stress Corrosion Cracking (SCC): Exceptional resistance to chloride and sour (H₂S) environments. Qualified per NACE MR0175 for oil & gas applications .
- Pitting and Crevice Corrosion: Superior resistance to localized corrosion in seawater and brine solutions due to high chromium (19%) and molybdenum (7%) content. Virtually immune to crevice corrosion and pitting even at the highest strength levels .
- Hydrogen Embrittlement: Excellent resistance to hydrogen embrittlement when properly heat treated .
- Hot Corrosion Resistance: Superior hot corrosion resistance at elevated temperatures due to formation of dense Cr₂O₃ protective film, promoted by high Cr content and the presence of Nb . Long rod-like γ' phases provide outward diffusion channels for Cr, accelerating formation of protective oxide layers .
- Seawater Performance: In seawater, MP159 is virtually immune to crevice corrosion, stress corrosion cracking, and pitting .
- Biocompatibility: Fully biocompatible for medical implant applications .
- Bimetallic Corrosion: Can be safely connected to stainless steels, titanium alloys, and other corrosion-resistant alloys with appropriate precautions.
Manufacturing Standards – MP159 Set Screws
All MP159 set screws are manufactured and tested to meet the following standards:
We offer surface finishes: passivation (ASTM A967), silver plating (AMS 2410 for anti‑seize), PTFE coating, electropolish. Full traceability and destructive/non‑destructive testing available (UT, MPI, PMI). ISO 13485 certified for medical applications with cleanroom packaging available.
Why RAYCHIN LIMITED – The MP159 Set Screw Authority
Contact the MP159 set screw experts
Request a quotation for MP159 set screws, grub screws – any point style (cup, cone, flat, dog) – any standard (ASME, ISO, DIN) – any condition (AMS 5841, 5842, 5843), any quantity. Global delivery. Mechanical data in MPa/ksi available for all products.
sales@ray-chin.com | +86 534 2166 566Our team provides technical support in English, German, Mandarin, Japanese.
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