CAL3K Filling Station

The manual oxygen filling station is manufactured completely in house, which saves on costs and results in a reduced final price. It is light weight making it a lot easier to transport from place to place if needed. It is a lot easier to handle and safe (user-friendly). Being manufactured with different materials to those used before, makes it kinder to the environment (environmentally-friendly).

The manual filling station brings a fresh new look to the CAL3K-A, CAL3K-U and CAL3K-F Oxygen Bomb Calorimeter Systems and future systems that will require the manual oxygen filling station to fill the vessel for analyses.

CAL3K Calorimeter Manual Oxygen Filling Station | DDS Calorimeters
CAL3K Calorimeter Manual Oxygen Filling Station | DDS Calorimeters
CAL3K Calorimeter Manual Oxygen Filling Station | DDS Calorimeters
CAL3K Manual Oxygen Filling Station - Handle and Pressure Gauge | DDS Calorimeters
CAL3K Manual Oxygen Filling Station - Improved Robust Handle & Nozzle | DDS Calorimeters

Prior to installation please make sure you have a suitable oxygen high pressure regulator. The regulator should be a high pressure regulator, capable of filling a vessel to a pressure of 3000Kpa.

The Filling Station is packed in its own box along with the other components and vessels, which are in their own plastic bag. Remove the foam, which holds the Filling Station in place. Before proceeding any further, inspect the Filling Station for any possible damages during transportation. If you find it to be damaged in any way, contact your Agent immediately. Also, check the packaging list and confirm all the contents.

The type of oxygen to be used is normal industrial oxygen, used for welding. A purity of 99.5% is suitable. The oxygen bottle should be firmly secured to a wall or pillar. Using the pressure pipe and connectors supplied, connect the Filling Station to the oxygen bottle. Slowly increase the pressure and check all connections for any possible leaks. If a connection is leaking, turn the oxygen off and disassemble the connection to ensure that the ferrule is sealing.

Once the Filling Station is installed and ready to use, place the Vessel on the base and lower the arm, ensuring that the Filling Station nozzle fits directly and cleanly over the Vessel's valve. Once the arm is fully down it will latch in this position and the Vessel will then fill, unattended. When the Vessel reaches the required pressure the arm can be lifted and the Vessel removed.

There are 2 pressure gauges on the Filling Station. The right hand gauge indicates the bottle or incoming pressure, and this should always be 3000Kpa. The gauge on the left indicates the Vessel or filling pressure. The rate of the filling is clearly visible on this gauge. One can fill the vessel to less than 3000Kpa (never more), however this will only be applicable when one is analyzing samples which are highly combustible (e.g. wood samples) and need less oxygen to burn. For samples such as these we recommend filling the vessel to 1500Kpa.

During normal operation the Filling Station requires very little maintenance. However it is suggested that the ex-center and piston be lightly silicone greased (NOT oiled) so as to minimize wear. Also, the o-ring in the nozzle should be lightly smeared with silicon grease daily to avoid the vessel from sticking to the nozzle when filling. Incorporated with the Filling Station are two holders on either side - one can be used for holding the handling hook and de-filler cap, while the other is to hold the vessel's lid assembly.

WARNING : NEVER use any oil or oil based lubricant on the Filling Station and Vessel. A light (small) amount of special silicone grease can be used on the Filling Station Nozzle O-Ring, Lever, Piston and Ex-Center. DO NOT use silicone grease on any part of the VESSEL.

The CAL3K Filling Station Installation Kit includes : 2 x Flow Adjuster O-Rings (3K-3-FR), 5 x Nozzle O-Rings (3K-3-NR), 1 x High Pressure Pipe 4mm (2m, clear)(3K-3-OP), 1 x Oxygen Regulator Connection (3K-3-RC) and 1 x Defiller Cap (3K-4-DC).


The Filling Station was designed to be as simple as possible to use by the operator and to have as few adjustments as possible. There are only two adjustments which may be required on the Filling Station:

Firstly, the plastic base is adjusted so that the Vessel valve is directly under the Filling Station's nozzle. This is adjusted in the factory and should not required adjustment again. However, if an adjustment is necessary, the following procedure should be followed:

  1. If the Filling Station is bolted to the table, remove the bolts.
  2. Loosen the screw, which holds the plastic base to the base of the Filling Station.
  3. Place a Vessel in the disc and lower the arm of the Filling Station, ensuring that the nozzle fits cleanly onto the Vessel's valve, until the arm latches down all the way.
  4. Now tighten the plastic base's screw from underneath.
  5. Check the alignment and if correct, bolt the Filling Station back to the table.

Secondly, adjustment to the rate of filling the vessel may be needed. This is adjusted by the Flow Adjuster screw on the right hand side of the gauge block holder, next to the bottle pressure gauge. This screw is already adjusted at the DDS factory so that a vessel will fill up to 3000Kpa in about 20 seconds. Turning the screw inwards (clockwise) will reduce the flow and thus the vessel will take longer to fill. Turning the screw outwards (counter clockwise) will increase the flow enabling the vessel to fill faster. When turning the screw inwards, do not over tighten, as this will damage the plastic nipple inside.

When turning the screw outwards great care must be taken. The screw must NOT be turned more than 2 turns from its original position.

WARNING : Over turning can cause the screw to be blown out of the threads by the pressure. This can result in damage or cause injury to the operator.

The filling time should be varied between 30-60 seconds only. The actual time being chosen should be in accordance with the operator's experience and speed.

One more adjustment which could be required is that of the Bottle Pressure. This should always be set to 3000Kpa to allow the vessel to fill unattended. If the pressure is set correctly the vessel will not overfill. Please remember that with high combustible samples which require less oxygen to burn, it is advisable to fill the vessel to 1500Kpa.

The absolute maximum pressure to which the incoming pressure can be set is 4000Kpa.

WARNING : Any additional pressure can cause damage to the Filling Station or even injury to the operator. If a vessel is filled to below 3000Kpa, and the sample being analyzed does not have a high combustion, there is a chance you will receive a misfire error as there is not enough oxygen in the vessel to burn the sample. However, as mentioned already this may not happen if the sample you are analyzing is highly combustible and needs less oxygen to ignite.


The Filling Station is used to pressure the vessel with oxygen to 3Mpa (3000Kpa) or less as with some applications which have samples that ignite easily. However, you may need to fill the vessel to more than 3000Kpa. This is required so that the sample will ignite and then burn away completely. The oxygen rich environment allows quick and complete combustion of most samples.

Width = 220mm

Height = 450mm

Depth = 300m

Weight = 4.5Kg

  • Secure the Filling Station to the table.
  • Install the flexible high pressure pipe supplied without any sharp bends.
  • Check the nylon high pressure pipe supplied for any mechanical damage before putting it under pressure.
  • Secure the pipe nuts to the pressure regulator side, then clamp the ferrule to the high pressure pipe on the gauge block side.
  • If the oxygen bottle is not situated close to the Filling Station or if it is in another room or perhaps outside, then a solid, permanent installation of pressure piping should be installed, as well as a shut off valve and pressure gauge within easy reach of the CAL3K Filling Station.
  • If bottled oxygen is used, a suitable High Pressure Oxygen Regulator must be supplied by your agent , or sourced locally. Ordering this item from the factory ensures that the necessary modifications have been made to fit the CAL3K Filling Station.
  • The oxygen bottle should be secured according to regulations.
  • NOTE : With some applications you may need to fill the vessel to less than 3000Kpa e.g. 1500Kpa (15 bar), however this is only applicable when you have a sample which is highly combustible, for example with wood related samples.
  • REMEMBER : You may fill the vessel LESS than 3000Kpa but NEVER more than 3000Kpa.
  • The type of oxygen to be used it the standard industrial oxygen used for welding. A purity of 99.5% will be suitable.
  • Conform to the industry standard of handling procedures for oxygen bottles.
  • Secure the bottle against a wall.
  • NEVER use oil or grease on any part of the gauge assembly or any part of the Filling Station and Vessel for SAFETY reasons!
  • DO NOT use a hammer to free a jammed valve!
  • Use only the approved pressure reduction valve with a safety blow valve.
  • Consult your safety engineer when in doubt.
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