Description
The FOX BTHX Series Flat Diaphragm – Bellows Pulsation Damper stands out for the use of high-quality materials, designed for demanding industrial applications. The main body of the accumulator is entirely made of AISI 316 L stainless steel, giving the device remarkable strength and long-lasting durability. The internal flexible element, available in the dual version as a flat diaphragm or bellows, is made of PTFE, a material commonly known as Teflon. The unit integrates as standard a nitrogen valve with 5/8 UNF thread, essential for managing gas pre-charge. To meet specific technical specifications, versions in exotic materials and FDA-certified versions for the diaphragm or bellows can be supplied. For pharmaceutical applications, a lapped or electropolished version can be requested to ensure maximum hygiene of the contact surfaces.
Technical Specifications and Operating Principle
From an operational standpoint, the BTHX Series is approved to support a maximum working pressure (PS) of 150 bar. The testing procedures include a test pressure (PT) calculated by multiplying the working pressure by coefficients of 1.43, 1.3 or 1.5, confirming the high structural safety margin of the component. When used specifically as a pulsation damper, calibration plays a decisive role: the nitrogen pre-charge pressure must be strictly maintained within a range between 60% and 80% of the working pressure. This calculation must necessarily take into account both the type of pump installed in the hydraulic circuit and the operating temperature of the fluid. The mechanical life of the device is inversely proportional to the increase in the compression ratio, making correct initial configuration essential.
Installation and Available Variants
The mechanical design of the device ensures outstanding mounting flexibility, allowing installation on both horizontal and vertical axes, with the sole requirement of always keeping the nitrogen valve oriented upwards. In addition to the basic configuration, the range includes numerous customisation options on request. Hydraulic connections can be supplied in different variants, including SAE 3000, SAE 6000, ANSI B16.5 and UNI/DIN flanges, as well as special connections such as API spec. 6A type 6BX, Autoclave, Grayloc and integrated flange systems. Aesthetically and functionally, the external body can receive an epoxy coating in accordance with the standard FOX procedure or according to specific project directives. For system architectures operating under extreme conditions, special versions for high pressures and non-standard volumes are available. Where the use of stainless steel is not mandatory, the manufacturer also offers the BTH series, characterised by a carbon steel construction.
Summary technical table of the main features
| Feature |
Value |
| Maximum working pressure (PS) |
150 bar |
| Test pressure (PT) |
PS x 1.43 / 1.3 / 1.5 |
| Body Material |
AISI 316 L stainless steel |
| Diaphragm / Bellows Material |
PTFE (Teflon) |
| Standard nitrogen valve |
5/8 UNF |
| Installation |
Horizontal / vertical (nitrogen valve facing upwards) |
| N2 pre-charge pressure (Damper) |
From 60% to 80% of the working pressure |
Product Codes
| Model |
Volume (Lt) |
Max Pressure (Bar) |
Max N2 Pre-Charge (Bar) |
Hydraulic Connection |
Weight (Kg) |
| BTHX0.06 |
0.06 |
150 |
105 |
1/4″ BSP-F |
3.9 |
| BTHX0.15 |
0.15 |
150 |
105 |
3/4″ BSP-F |
5.2 |
| BTHX0.3 |
0.3 |
150 |
105 |
3/4″ BSP-F |
6 |
| BTHX0.5 |
0.5 |
150 |
105 |
3/4″ BSP-F |
7 |
| BTHX0.7 |
0.7 |
150 |
105 |
” BSP-F |
8 |
| BTHX1 |
1 |
150 |
105 |
1-1/2″ BSP-F |
11 |
| BTHX1.5 |
1.5 |
150 |
105 |
1 1/2″ BSP-F |
13 |
| BTHX2.5 |
2.5 |
150 |
105 |
1-1/2″ BSP-F |
15 |
| BTHX3 |
3 |
150 |
105 |
1-1/2″ BSP-F |
19 |
| BTHX4.5 |
4.5 |
150 |
105 |
1-1/2″ BSP-F |
24 |
| BTHX6.5 |
6.5 |
150 |
105 |
1-1/2″ BSP-F |
35 |
| BTHX10 |
10 |
150 |
105 |
1-1/2″ BSP-F |
45 |
| BTHX12 |
12 |
150 |
105 |
1-1/2″ BSP-F |
54 |
| BTHX15 |
15 |
150 |
105 |
3″ BSP-F |
68 |
FOX BTHX Series Flat Diaphragm / Bellows Pulsation Dampener