Hydac SBO200-1E1/112S-210AB Diaphragm Accumulator, 1 L

A compact 1 litre diaphragm accumulator with a rechargeable gas valve

The Hydac SBO200-1E1/112S-210AB (HYDAC part number 2101508) is a welded, non-repairable diaphragm accumulator with a nominal volume of 1 litre (0.264 gallon). The gas and oil are separated by an NBR diaphragm in a carbon steel shell, which gives a compact and light unit suited to pulsation damping, shock absorption and small energy-storage tasks, for example on pump outlets of presses and machine tools.

It has HYDAC gas valve version 1 (M28x1.5), so the precharge can be checked and refilled. The fluid port is a combination connection: a G1/2 BSPP female thread plus an M33x1.5 male thread.

Technical specifications

Reading the model code

SBO 200 – 1 E1 / 112 S – 210 AB: SBO is the diaphragm series; 1 is the size in litres; E1 is welded construction with a rechargeable gas valve (version 1, M28x1.5); 112 is the standard code for oil service; S is the USA country of installation; 210 is the working pressure in bar; AB is the male and female combination fluid connection. Other connection codes include AK (BSP) and CK (SAE).

Using diaphragm accumulators

Diaphragm types respond quickly and weigh little, but they hold smaller volumes and flows than bladder types, with a rated flow of 25 gpm here. They can be installed in any position; where contamination is a problem HYDAC recommends a vertical mount with the fluid port pointing down. The welded shell is not repairable, so a failed diaphragm means replacing the accumulator. Confirm the diaphragm compound against the fluid and the country approval required by your installation, as the code shown is the USA one.

Use mounting hardware from the accessory range for vibrating machines, and keep the precharge record. Pre-charge only with nitrogen and relieve the fluid side first when checking the gas pressure. HYDAC lists agricultural, forestry, machine tool, mining and mobile equipment among the common uses of diaphragm accumulators, and notes that they suit low-lubricity fluids such as water when the right shell and compound are selected, so confirm the combination for your fluid.

When the unit is installed, register the gas precharge pressure and the date on the machine file, and recheck it after the first week of service. Gas loss is the usual cause of accumulator failure, and regular checks are cheaper than an unplanned stop.

Documents and quotation

The diaphragm accumulator datasheet is attached. Please specify the precharge pressure and the fluid. See also our hydraulic valves and components category.

How the SBO200-1E1/112S-210AB works

The SBO200-1E1/112S-210AB is a hydro-pneumatic accumulator. Inside the shell an elastomer diaphragm divides the volume into a gas side, precharged with nitrogen through the gas valve, and a fluid side connected to the hydraulic circuit. When the system pressure rises above the precharge pressure, oil flows into the shell and compresses the nitrogen. When the pressure falls, the gas expands and pushes the oil back into the system. A poppet fixed to the diaphragm closes the fluid port when the accumulator is empty, protecting the diaphragm from being extruded into the port.

HYDAC makes two types of diaphragm accumulator with the same basic construction. The welded version, used in this model, has an electron-beam welded shell and therefore cannot be repaired. The threaded version has two shell halves held by a threaded locking ring. HYDAC describes diaphragm accumulators as a cost-effective option where smaller volumes and flow rates are adequate and where a compact design, low weight, flexible mounting positions and an extremely quick shock response are needed.

Datasheet dimensions for the 1 litre SBO 200

Dimensions are for general information only and critical dimensions should be verified. The diameter at the weld seam may be slightly larger than ØD.

SBO200-1E1/112S-210AB selection & ordering guide

• Shell and gas port: E1 = welded, rechargeable, HYDAC gas valve version 1 (M28 × 1.5). E2 is factory precharged and sealed (not rechargeable), E4 uses gas valve version 4 (8V1, ISO 4570), and A6 is the threaded repairable construction.
• Diaphragm compound: NBR is standard for mineral oil (5 to 180 °F). Other listed compounds are low-temperature NBR, ECO, IIR for phosphate esters and brake fluids, and FPM for chlorinated hydrocarbons. Always refer to the fluid manufacturer’s recommendation.
• Corrosion protection: coatings, chemically plated carbon steel and stainless steel parts are offered for water service or aggressive environments. Stainless versions may have a lower MAWP.
• Fluid port: AB = male/female combination; AK = BSP; CK = standard SAE.
• Precharge: a three-digit gas precharge in bar can be added to the code; it is always required for the sealed E2 version.

Our team can help confirm the correct ordering code if you need a different port, compound or approval.

Installation & maintenance

• Diaphragm accumulators can be mounted in any position. Where contamination is a problem, HYDAC recommends a vertical mount with the fluid port pointing down.
• The unit is designed to be screwed directly onto the system; HYDAC mounting components are recommended to minimise the risk of failure from vibration.
• Never exceed the maximum pressure ratio of 8:1 between maximum working pressure and precharge.
• Precharge with nitrogen only, and depressurise the fluid side before checking the gas pressure.

Typical applications in Oman & the GCC

HYDAC lists agricultural machinery, forestry, machine tools, mining, mobile and construction equipment and off-road equipment as common applications. In Oman and the GCC, a 1 litre diaphragm unit is typically used for pulsation damping on pump outlets, shock absorption on mobile machines, pressure maintenance in clamping circuits and leakage compensation on small hydraulic power units.

Why source from Seven Star LLC

Seven Star LLC supplies HYDAC diaphragm accumulators, charging units and mounting clamps across Oman and the GCC. Request a quote for the SBO200-1E1/112S-210AB with your precharge pressure and fluid.