Grade 2 Titanium Machine Screws
Grade 2 titanium machine screws are commercially pure UNS R50400 threaded fasteners used where low mass and resistance to many chloride-bearing, marine and process environments are important. SAKY ALLOY supplies machine screws by specified head style, drive, thread, length, finish, inspection and documentation requirements.
Grade 2 Machine Screw Supply Range
| Material | Titanium Grade 2, commercially pure titanium, UNS R50400 |
| Head styles | Pan head, cheese head, raised or drawing-specific head forms by review; countersunk screws are covered by a separate product family |
| Drive options | Slotted, cross recess, six-lobe and other drawing-defined recesses |
| Threads | Metric coarse or fine and inch-series threads when specified; thread class and gauge acceptance must be stated |
| Dimensional references | ISO 7045 cross-recessed pan head geometry, ISO 1580 slotted pan head geometry, legacy DIN references or customer drawings when expressly invoked and reviewed for titanium |
| Finish | Clean machined or formed surface; application-specific finish, lubrication or anti-galling treatment by agreement |
| Documentation | Material test certificate, dimensional report, thread inspection and lot traceability as specified |
Head and Drive Selection
A pan head provides a broad bearing surface and a low-to-moderate profile for covers, instruments and equipment panels. Cheese-head geometry offers a cylindrical side profile and may be chosen where head diameter or tool access is controlled. The head diameter, height, under-head radius and bearing surface should be taken from the invoked standard edition or drawing.
Cross recesses support common assembly tools, but the recess type must be identified because similar-looking drives are not necessarily interchangeable. Slotted drives can suit simple maintenance access but may provide less positive tool engagement. Six-lobe drives can reduce cam-out when the recess and driver are correctly matched. Drive dimensions, installation torque and tool access should be reviewed together.
SAKY ALLOY also supplies a separate range of Grade 5 titanium countersunk screws where a flush seating surface is required.
Standards and Specification Boundaries
ISO 7045:2011 defines product-grade-A pan head screws with type H or Z cross recess in its stated scope. ISO 1580 covers slotted pan head screw geometry. These documents provide useful dimensional references, but their published material or property-class provisions are not a blanket titanium fastener specification.
When a buyer requests a titanium machine screw using one of these geometries, the purchase order should separately define Grade 2 / UNS R50400, the required material specification, any finished-fastener mechanical requirements and the inspection criteria. Legacy DIN designations may still appear on drawings; the quoted revision and any superseding ISO reference should be confirmed before manufacture.
ASTM F468 covers specified nonferrous externally threaded fasteners for general use, but its applicability to a particular small machine-screw style, size and order must be checked rather than assumed. If ASTM requirements are invoked, state the current edition, alloy designation, dimensions, tests and supplementary requirements.
Why Specify Grade 2 Titanium?
Grade 2 titanium develops a stable passive oxide film in many oxygenated aqueous environments. This can make it useful in marine equipment, desalination systems, heat-exchanger assemblies, chemical-processing equipment and other applications where the selected environment is compatible with commercially pure titanium.
Corrosion resistance is environment-specific. Dry chlorine, strongly reducing media, fluoride-containing solutions, crevices, temperature and galvanic contact can change material behavior. The equipment designer should review the actual chemical composition, concentration, temperature, aeration and joint geometry. A general statement that titanium is corrosion resistant is not a substitute for application approval.
Grade 2 is not a direct substitute for Grade 5. Grade 5 Ti-6Al-4V is normally considered where higher strength is required, while Grade 2 is often selected for corrosion resistance, formability and commercially pure titanium chemistry. The responsible engineer should confirm load capacity and joint design.
Threads, Length and Tolerances
Specify the complete thread designation, including nominal diameter, pitch or threads per inch, tolerance class and right- or left-hand direction where applicable. For metric threads, a drawing may reference ISO general-purpose thread tolerances. For inch threads, state the unified series and class. Thread acceptance should identify the applicable GO/NO-GO gauges or measurement method.
Machine-screw length is normally measured from the bearing surface beneath a non-countersunk head to the end, but the governing standard or drawing controls. Define any unthreaded portion, point form, end chamfer, head concentricity and runout requirements that affect installation. Very small screws may require agreed sampling and measurement methods.
Galling and Assembly Review
Titanium threads can gall when contact pressure, friction, surface condition and installation speed create adhesive transfer. Risk can increase in titanium-on-titanium assemblies. A validated assembly plan may use compatible mating materials, controlled cleanliness, an approved lubricant or coating, and an installation speed and torque procedure established by the joint designer.
Do not apply a generic steel-screw torque table to Grade 2 titanium. Installation torque depends on screw geometry, material condition, lubrication, mating thread, joint stiffness and required clamp load. For critical equipment, torque-tension or other assembly validation may be appropriate.
Inspection and Quality Documentation
- Material identity and heat or lot traceability as ordered
- Head diameter, height, recess and under-head geometry
- Overall length and threaded length
- Thread gauge inspection to the specified class
- Surface and visual examination
- Chemical and mechanical test records when invoked
- Special-process or cleanliness records when required
State whether the order requires a certificate of conformity, material test certificate, dimensional report, first-article inspection or third-party inspection. Documentation should be agreed before production because it affects material control, sampling, cost and delivery.
Typical Applications
Potential uses include instrument housings, equipment covers, marine hardware, chemical-processing accessories, desalination assemblies and other lightly or moderately loaded joints approved for Grade 2 titanium. Suitability must be confirmed for the actual load, temperature, chemicals, vibration, electrical contact and maintenance plan.
Frequently Asked Questions
Are Grade 2 machine screws fully threaded?
Many short machine screws are fully threaded, but thread length is controlled by the selected standard or drawing. State the required length and thread engagement in the RFQ.
Can ISO 7045 be specified for titanium?
Its geometry may be invoked by agreement, but the buyer must separately specify titanium material, mechanical requirements and inspection because the ISO scope does not automatically create a Grade 2 titanium product specification.
Can SAKY ALLOY supply custom drives or head dimensions?
Drawing-specific configurations can be reviewed. Send a controlled drawing with tolerances, recess details, material specification, quantity and inspection requirements.
Request Grade 2 Titanium Machine Screws
For a technically comparable quotation, include the material grade, standard or drawing, head, drive, thread, size, quantity, finish, inspection and required delivery destination.