FAQ

FAQ 2017-09-16T00:58:30+00:00

TiNi AEROSPACE, INC.

AS9100 Rev B and ISO 9001:2008 Registered
Yes, approximately 30% of our business is for Engineering work which may include Design, R&D, Testing, etc.
No, all products must be purchased directly from TiNi Aerospace. We do however have partners in Italy, Japan, and elsewhere to facilitate this process and provide further support if needed.
Yes, the export of all TiNi products (and information) is controlled under ITAR (International Trade of Arms Regulations) under the U.S. Department of State. This is not because TiNi products directly provide a military function but rather because they are used aboard satellites or spacecraft. Per category XV of the USML (United States Munition List) the export of all parts and components used on a spacecraft is ITAR controlled.
We routinely file for and receive an export license for shipments to ally countries. This typically takes 2-3 weeks and only requires an “End User Declaration” by our customers. Shipment to Embargo countries is however forbidden. See list at www.pmddtc.state.gov Example of countries that are currently on this list include China, North Korea, Cuba, Iran, Fiji, Venezuela, and Libya.
Yes, our QMS (Quality Management System) has been certified to AS-9100 since 2005, and to ISO 9001 standard since 1999.

Shape Memory Alloys

SMAs do not operate based on volumetric expansion as in paraffin or wax type actuators. Rather Shape Memory Alloys are able to recover from “deformation” by heating from one state to another. The mode of deformation and subsequent recovery can be in all directions (i.e. tensions, compression, bending, twisting, or any combination thereof). Recoverable strains for binary Nitinol is in the order of 4% where single crystal derivatives can exceed 10%.

No, unlike bi-metallic actuators or devices which operate based on material CTE (Coefficient of Thermal Expansion) SMAs recovery from one state to another occurs over a narrow temperature range (approximately 10C). This is analogous to water boiling when it gets to 100C (i.e. there is a “state change” which occurs relatively abruptly when the material hits a critical temperature).

Titanium Nickel based alloys can generally go up to 100C. Copper based alloys (such as our SCSMA) can go up to 200C.

Yes, the transition temperature can be raised with load or stress. The value is typically in the order of 1°C/ksi. As an example, an element that has a free recovery transition temperature of 70C will exhibit an In-Situ actuation temperature of 100C if under a load of 30ksi.

Super-Elasticity refers to the ability of Shape Memory Alloys to spring back after exposure to significant deformation. For SCSMAs this can be 9% strain (or more) which is approximately 20 times greater than normal metals.

FRANGIBOLTS

The Actuator is typically housed in an enclosure which keeps it in a confined cavity after actuation. The opposing bolt segment may be automatically secured by threading directly into the deployable or similarly retained by using a retainer.

No. The Frangibolt Actuator has adequate stroke to function even if the bolt or Fastener is not preloaded. Joint preload is generally an application requirement to “hold down” the item being secured to avoid “rattle” under high G conditions such as launch. It is important however that the Frangibolt joint does not have, or develop, any gaps or compliancy which can rob the Actuator of stroke needed to fracture the bolt.

Verification that the Frangibolt has been reset correctly is by measuring its compressed length. This value should be within +0.005″ of previously recorded value for the particular Serial Number. Maintaining a log of all firings is therefore very important for critical applications.
No, the Frangibolt Actuator can be exposed to the compression force repeatedly without any effect on performance. Generally, once the Actuator has been reset, the application of the same force will not result in any further compression.
The fully recovered length of the Actuator can only be measured while hot (at approximately 100C). Any other measurement will be less than that due to either incomplete transformation or self-shortening which can occur during cooling.
This is because the embedded temperature sensor (RTD element) does not read the exact temperature of the TiNi cylinder which governs actuation (i.e. it happens to be at a colder spot within the heater assembly). Note that this also depends on power applied and starting temperature (i.e. the temperature distribution may differ from cycle to cycle depending on these external conditions).
No, the Frangibolt Fastener is an integral part of the overall mechanism and must be manufactured by TiNi Aerospace. This is done to very high standards requiring a significant amount of inspection and testing of every Lot produced. Furthermore, the notch profile and material used are key in providing the proper performance.
Power is typically shut off based on either a timed pulse, maximum temperature read, or using an inline shut off switch.
Generally, the Frangibolt temperature (as read by the embedded RTD) should not be allowed to exceed 150C. However, it is highly recommended that the customer perform worst case system level testing to quantify both the function time and max temperature for the particular conditions of the application. This is typically enveloped by high voltage/temperature and low voltage/temperature which result in the fastest and slowest function time, respectively.
Yes, as long the Actuator is allowed to cool back down to room temperature 23 +/- 5 C.

Pinpullers

No, the Pin is retracted under the force of a “Compression Spring” made of conventional materials. Rather, the SMA (or TiNi) is used to release the latch which initiates movement.
Yes, we routinely do this for many applications by simply incorporating an inline resistor which is capable of dissipating the power required. Generally, this is not a problem because the function times are sub-second and therefore result in very little energy (Joules) dissipated.
As an example, TiNi’s P10 Pinpuller provides a minimum force available at the start of the travel which is 10 lbf. The retraction force at the end of travel however may be significantly lower at approximately 5 lbf. This is consistent with the requirements of most applications where the maximum required force is at the start of travel when overcoming static friction.
Yes, unless otherwise required, all TiNi products are vented for space use.
As with all such applications, it is best to apply the load as close to the supported section (Pinpuller Flange) as possible. However, the quoted specification is based on worst case situations where the load is applied at the end of the Pin forming the greatest moment.
The TiNi element is “Joule Heated” (i.e. the current is passed directly through it such that it can be heated very quickly).
This is limited by the self-actuation temperature of the device (i.e. the maximum operating temperature must not exceed the temperature at which point the device risks functioning without the application of power). All TiNi standard products maintain a conservative margin of 20C from this temperature.
Yes, a small amount of wet lubricant in the form of Castrol Braycote 601 EF is used during assembly. This can be omitted entirely or changed to other lubricants if required. Also, sliding parts are generally plated with MoS2 or Teflon impregnation as offered by companies such as Tiodize (El Segundo, CA).
No, we do this routinely and unless the working mechanism is changed and a “delta-qualification” effort becomes necessary, modifications such as these are simple, quick, and not expensive.
No, all of our products are deemed capable of thousands if not many millions of cycles. The rated Life of approximately 100 cycles (for all actuators) is therefore based on applications requirements and not what the device can do.

EJECTORS (ERMs)

The ERMs are nearly identical to our Pinpullers in that they share more than 90% of the same parts. However, by adding a ball lock at the coupler interface the load rating is increased by more than one order of magnitude to provide a unique and powerful NEA (Non Explosive Actuator).
These can be reset within seconds although it is best to wait at least 3 minutes to ensure that the TiNi element has cooled back to room temperature.
No, the ERM is similar to our Frangibolt in that it should be exposed to axial loads (resulting from joint preload) only. Of course the friction in any such bolted joint is capable of reacting to some amount of side load. However, a cup-cone interface between the structure and deployable is recommended if significant side loading is anticipated.
Yes, you can fire the ERM with nothing attached to the coupler. Generally, you will find that the force is light enough such that the ejected coupler is thrown into the air by only 5 feet or so. Therefore, cupping your hand over it is a common and acceptable method for retaining it. The only safety precaution should be to not put one’s head (or eye) directly in the path of the coupler.
No, TiNi’s early literature suggested that a “backing wrench” should be used but this is no longer the case. All ERMs are designed to be able to react to the recommended installation torque (i.e. as long as the ERM body is bolted to the structure, the coupler can be torqued into just like any other Nut or Threaded Hole).
Locking inserts (Heli-coils) installed into the Coupler are the most common approach. Also, other methods such as locking fluid or patches are acceptable. Aeronautical or military applications may benefit from the use of lock down wire as used on any other bolt or fastener.
Depending on the ERM size, the kick off spring applies a force of 2 to 10 lbf (i.e. very light). Its function is to eject the coupler in the event that no external load or preload is applied.
Yes, we have done this for many ERM and Pinpuller embodiments and found it be effective for pressures up to 1000 psi. However, if higher pressures (depths) are expected then the ERM (or Pinpuller) needs to be housed in a pressure compensating enclosure.
Yes, the internals of our ERMs and Pinpullers are nearly identical so many (if not all) Q+A relating to our Pinpullers also applies to our ERMs.

Load feedback is offered by installing calibrated strain gages directly in the ERM enclosure. This offers very accurate measurement of preload during torque up. This option is readily introduced into the bottom mount configuration where the Actuator enclosure is in the load path. It has also been incorporated into the Top Mount configuration where the enclosure is not in the load path by use of a “transfer tube”.