General Information
The HOKE Gyrolok Design
HOKE Gyrolok® Tube Fittings have been carefully designed and manufactured to provide a wide range of outstanding leak-tight application capabilities.
Materials
HOKE Gyrolok® fittings are available in:
| Brass | BR |
| 316 Stainless Steel | 316 |
| Monel® | M |
| Hastelloy® C: | HC |
| Inconel: | 600 |
| Titanium: | TI |
| Duplex 2205: | DX3 |
| Super Duplex 2507: | D50 |
| 254 SMO: | 6MO |
| 316 Stainless Steel Forgings: | ASTM A-182 / SA182 |
| 316 Stainless Steel Bar Stock: | ASTM A-479 / SA479 |
| Brass Forgings, Alloy 377: | QQ-S-626 |
| Brass Bar Stock, Alloy 353: | ASTM B-453 |
| Brass Bar Stock, Alloy 360: | QQ-B-16 |
| Monel Forgings, Alloy 400: | QQ-N-281 |
| Monel Bar Stock, Alloy 405: | QQ-N-281 |
Contact your local HOKE distributor for further information.
Certified Material Test Reports (CMTRs)
Bodies and nuts of HOKE Gyrolok® fittings in all materials other than Brass are heat code traceable. To obtain CMTRs for these components, place separate orders for such items and specify "CMTRs required on all items."
Pressure Rating
HOKE Gyrolok® fittings are rated for working pressures higher than the tubing recommended for use with HOKE Gyrolok®. Tubing should not be utilized at pressures above its maximum allowable working pressure. Check the HOKE Tubing Data Charts for specific information. If no pressure is identified for a given size and wall thickness of tubing, that tubing is not considered suitable for use with tube fittings. Pressure ratings may vary for other fitting ends, such as NPT or O-ring seal. Contact your distributor or Hoke for more information.
Vacuum Rating
HOKE Gyrolok® offers deep vacuum capability. With good quality tubing, HOKE Gyrolok fittings will be leak-tight at vacuum levels of 10-9 torr while tested with a leakage sensitivity of 10-9 sccs.
Temperature
HOKE Gyrolok® fittings provide safe, reliable performance from cryogenic temperatures to high temperature bake-out levels, depending on material.
- 316 Stainless Steel: -325° F to 800° F (-198° C to 426° C)
CAUTION: Intermittent use to 1200° F is possible, however, prolonged exposure to temperatures over 800° F is not recommended. - Brass (copper tubing): -325° F to 400° F (-198° C to 204° C)
- Monel: -325° F to 800° F (-198° C to 426° C)
Pipe Thread Information
HOKE Gyrolok® tube fittings are available with NPT (National Pipe Taper), BSP/ISO (British Standard Pipe/International Standards Organization) or unified screw threads.
Tapered Threads
| Specification(s) | Type | Part Number or Suffix Designation |
Sealing Method |
| NPT | M/F | Fitting type ends in M or F, as in CM or CF. | Seal is made on the thread. Thread sealant is required. |
| RT to ISO 7/1 BS 21 JIS B0203 DIN 2999 |
M/F M/F M/F Male |
Modifier is C | Seal is made on the thread. Thread sealant is required. The BSP/ISO thread utilizes a different angle and the number of threads per inch may differ. Reference DIN 3852, Form C. |
Straight or Parallel Threads
| Specification(s) | Type | Part Number or Suffix Designation |
Sealing Method |
| American Standard unified screw threads | Male | Fitting type ends in S, as in COS or AOS. | Generally utilizes an elastomer O-ring to provide sealing. |
| RP to ISO 228/1 BS 2779 JIS B0202 |
Male | Modifier is B | Metal-to-metal sealing to DIN 3852, Form B. |
| RS to ISO 228/1 BS 2779 JIS B0202 |
Male | Modifier is A | Utilizes a sealing washer to provide sealing. Reference DIN 3852, Form A. |
| RG to ISO 228/1 BS 2779 JIS B0202 |
Female | Modifier is Z | Sealing form meets DIN 16288, Form Z. |
Identifying Metric Gyrolok® Products
Hoke metric Gyrolok® products have certain features which allow you to identify them from the fractional products:
A. Step Machined on Body Hex
Straight bodies with a metric Gyrolok® end have a step machined on the tube fitting side of the hex.
B. Short Shank on Nut
Metric nuts are machined with a short shank on the threaded end.
C. Groove in Front Ferrule
Metric front ferrules made from brass or 316 stainless steel have a groove machined into the shoulder. For other materials, see MM Marking.
D. MM Marking
The metric designation "MM" is stamped on:
- metric nuts and straight bodies—after the Gyrolok® trademark
- metric elbows, tees and crosses—on the side opposite the Hoke logo
- front ferrules made from materials other than brass or 316 stainless steel—after material identification.
Color Coding
Blue boxes designate metric parts, while green boxes indicate fractionally sized items. Color is also used for all accessories, including Safety Changer packaging and Gyrogages®, to differentiate metric from fractional parts.