
Flexible Metal Hose Assemblies & Quick-Connect Hose Fittings
R-LOK flexible metal hose assemblies are corrugated stainless steel hoses with a stainless braid, furnished with the end connections your piping needs. They replace rigid tube runs that must absorb vibration, thermal growth or movement. The range covers a 1/4 in to 2 in bore in eight sizes, to 1,600 psig (110 bar), over -325 F to 800 F.
Products · Applications · Quality · Resources · About · Contact
Home › Products › Fluid Control › Hose Assemblies

Key features
- Corrugated stainless steel core with stainless steel braid, 1/4 in to 2 in
- Eight catalogue sizes: SFH4, SFH6, SFH8, SFH12, SFH16, SFH20, SFH24, SFH32
- Working pressure 1,600 psig (110 bar) at 1/4 in to 450 psig (31.0 bar)
- Burst pressure from 6,400 psig (440 bar) at 1/4 in to 1,800 psig
- End connections: socket tube, socket pipe, NPT male or female
- Metric tube ends in 6, 10, 12 and 20 mm, BSPP thread on request
Specifications
| Parameter | Value |
|---|---|
| Construction | corrugated stainless steel hose with stainless steel braid |
| Nominal bore | 1/4 in to 2 in (6.4 mm to 50.8 mm) in eight catalogue sizes |
| Catalogue series | SFH4, SFH6, SFH8, SFH12, SFH16, SFH20, SFH24, SFH32 |
| Working pressure at 70 F (20 C) | 1,600 psig (110 bar) at 1/4 in, 450 psig (31.0 bar) at 2 in |
| Burst pressure at 70 F (20 C) | 6,400 psig (440 bar) at 1/4 in, 1,800 psig (124 bar) at 2 in |
| Derating at 1/2 in (70 F, 204 F, 426 F) | 1,110 psig (76.4 bar), 1,032 psig (71.1 bar), 821 psig (56.6 bar) |
| Minimum bend radius, static (at 1/4 to 2 in) | 1.00, 1.81, 2.70, 5.10 in (2.54, 4.61, 6.86, 13.0 cm) |
| Minimum bend radius, dynamic (at 1/4 to 2 in) | 4.33, 6.50, 10.2, 15.4 in (11.0, 16.5, 25.9, 39.1 cm) |
What the assembly does
A corrugated metal hose bends where rigid tube cannot. The convolution absorbs movement, so the assembly takes pump and compressor vibration, small misalignment between fittings, and the growth of a hot pipe run without loading the joints at either end.
The stainless steel braid carries the pressure load and limits axial extension and lateral movement. It also protects the corrugation from abrasion. The stainless core avoids the aging, permeability and temperature limits of a polymer hose.
Sizes and ratings
Eight nominal bores are listed under the SFH series: SFH4, SFH6, SFH8, SFH12, SFH16, SFH20, SFH24 and SFH32, from 1/4 in to 2 in (6.4 mm to 50.8 mm).
At 70 F the working pressure: 1,600 psig (110 bar) at 1/4 in, 1,470 (101) at 3/8 in, 1,110 (76.4) at 1/2 in, 860 (59.2) at 3/4 in, 680 (46.8) at 1 in, 520 (35.8) at 1 1/2 in, 450 (31.0) at 2 in.
End connections and ordering
The ordering code names the ends after the series: S for socket tube, T for socket pipe, M for NPT male, F for NPT female. Socket tube ends cover 1/4 in to 1 in, with A dimensions from 47.5 mm to 81.3 mm.
NPT male and female ends are catalogued in 1/4 in, 3/8 in, 1/2 in, 3/4 in, 1 in, 1 1/4 in and 2 in, and the two ends can be mixed. Female socket ends are catalogued separately for brazing or welding.
Standards referenced: NPT thread form per ASME B1.20.1; BSPP and ISO taper per the catalogue thread code table; Hose and fitting materials referenced to AISI 316 and AISI 304 stainless steel; Coupling body, stem and sleeve materials referenced to ASTM A479 and ASTM A276 (316 stainless), brass per B16.
Typical duties: Pump and compressor discharge; Tank, vessel and skid nozzles; Steam and thermal fluid lines; Chemical transfer lines; Analyzer and sampling points; Offshore wellhead panels.
SFH series flexible metal corrugated hose model selection guide
| Series / model | Size | Connection | Working pressure | Body material | Notes |
|---|---|---|---|---|---|
| SFH4 | 1/4 in. | NPT male M4N (1/4); NPT female F4N (1/4); ferrule S4 (1/4 in. tube OD); sleeve T4 (1/4 in. tube OD); end type selectable per end | 1600 psig (110 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 6400 psig (440 bar) at 70 degF (20 degC); min. bend radius 1.00 in. (2.54 cm) static, 4.33 in. (11.0 cm) dynamic; 1184 psig (81.5 bar) at 800 degF (426 degC); dim. A 47.5 mm (S4), 43.2 mm (M4N), 46.0 mm (F4N), 38.6 mm (T4) |
| SFH6 | 3/8 in. | NPT male M6N (3/8); NPT female F6N (3/8); ferrule S6 (3/8 in. tube OD); sleeve T6 (3/8 in. tube OD); end type selectable per end | 1470 psig (101 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 5880 psig (405 bar) at 70 degF (20 degC); min. bend radius 1.20 in. (3.05 cm) static, 5.91 in. (15.0 cm) dynamic; 1088 psig (74.9 bar) at 800 degF (426 degC); dim. A 50.8 mm (S6), 48.5 mm (M6N), 46.7 mm (F6N), 46.0 mm (T6) |
| SFH8 | 1/2 in. | NPT male M8N (1/2); NPT female F8N (1/2); ferrule S8 (1/2 in. tube OD); sleeve T8 (1/2 in. tube OD); end type selectable per end | 1110 psig (76.4 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 4440 psig (305 bar) at 70 degF (20 degC); min. bend radius 1.50 in. (3.81 cm) static, 6.50 in. (16.5 cm) dynamic; 821 psig (56.5 bar) at 800 degF (426 degC); dim. A 61.7 mm (S8), 58.9 mm (M8N), 62.2 mm (F8N), 54.9 mm (T8) |
| SFH12 | 3/4 in. | NPT male M12N (3/4); NPT female F12N (3/4); ferrule S12 (3/4 in. tube OD); sleeve T12 (3/4 in. tube OD); end type selectable per end | 860 psig (59.2 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 3440 psig (237 bar) at 70 degF (20 degC); min. bend radius 2.10 in. (5.33 cm) static, 8.86 in. (22.5 cm) dynamic; 636 psig (43.8 bar) at 800 degF (426 degC); dim. A 66.5 mm (S12), 62.3 mm (M12N), 61.2 mm (F12N), 63.5 mm (T12) |
| SFH16 | 1 in. | NPT male M16N (1); NPT female F16N (1); ferrule S16 (1 in. tube OD); sleeve T16 (1 in. tube OD); end type selectable per end | 680 psig (46.8 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 2720 psig (187 bar) at 70 degF (20 degC); min. bend radius 2.70 in. (6.86 cm) static, 10.2 in. (25.9 cm) dynamic; 503 psig (34.6 bar) at 800 degF (426 degC); dim. A 81.3 mm (S16), 77.5 mm (M16N), 74.2 mm (F16N), 75.9 mm (T16) |
| SFH20 | 1 1/4 in. | NPT male M20N (1 1/4); ferrule S20 (1 1/4 in. tube OD); sleeve T and NPT female F not published for this size | 680 psig (46.8 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 2720 psig (187 bar) at 70 degF (20 degC); min. bend radius 3.10 in. (7.87 cm) static, 11.8 in. (30.0 cm) dynamic; 503 psig (34.6 bar) at 800 degF (426 degC); dim. A 96.3 mm (S20), 79.8 mm (M20N) |
| SFH24 | 1 1/2 in. | NPT male M24N (1 1/2); NPT female F24N (1 1/2); ferrule S24 (1 1/2 in. tube OD); sleeve T not published for this size | 520 psig (35.8 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 2080 psig (143 bar) at 70 degF (20 degC); min. bend radius 3.90 in. (9.91 cm) static, 13.4 in. (34.0 cm) dynamic; 385 psig (26.5 bar) at 800 degF (426 degC); dim. A 108.0 mm (S24), 85.9 mm (M24N), 83.3 mm (F24N) |
| SFH32 | 2 in. | NPT male M32N (2); ferrule S32 (2 in. tube OD); sleeve T and NPT female F not published for this size | 450 psig (31.0 bar) at -325 to 300 degF (-200 to 148 degC) | Stainless steel (grade not published) | Min. burst 1800 psig (124 bar) at 70 degF (20 degC); min. bend radius 5.10 in. (13.00 cm) static, 15.4 in. (39.1 cm) dynamic; 333 psig (22.9 bar) at 800 degF (426 degC); dim. A 133.0 mm (S32), 92.2 mm (M32N) |
Selection notes: Source: SFH series flexible metal corrugated hose tables on catalogue footers 14-09, 14-10 and 14-11; the section divider page (JPEG page189) carries no footer number. SFH series characteristics block states a stainless steel hose and a maximum working pressure of 1600 psig (110 bar), with sizes 1/4 in. to 2 in. and 6 mm to 38 mm and selectable end connections.
Catalogue reference 14-09, 14-10, 14-11. Confirm the final rating against the data sheet issued with your order.
See also: Filters · Fluid Control Accessories · Quick Connectors
Frequently asked questions
What is the minimum order quantity?
Small orders are accepted, including single assemblies cut to length for a trial or a repair. The price per metre improves on batch orders where several sizes share one shipment. Send the line list and we quote each assembly separately.
Which pressure applies to a hose at 250 F?
Use the pressure-temperature table, not the 70 F column. At 1/2 in bore the catalogue lists 1,110 psig (76.4 bar) at 70 F and 955 psig (65.7 bar) at 260 F. Give us the design temperature, fluid and bore and we quote the allowable pressure.
Can a hose carry different ends?
Yes. The ordering code carries two separate end-connection blocks, so any catalogued combination is possible, including NPT male to socket tube, female NPT to metric tube, or BSPP on one end. Non-standard lengths are quoted to the assembly drawing.
Request a quote or technical clarification
Send us the model, size, material and quantity you need — or a photo of the existing part. We reply with a quotation, availability and the applicable documents, usually within one working day.
Tel / WhatsApp: +86 136 5741 6007 · Email: nimo@runda-hitech.com