The Hydra-Cat has been specifically developed to apply 2 component coatings including Urethane and Epoxy based materials.

Many machines are in use both in the UK and overseas and experience has shown that the Hydra-Cat performs well in all conditions and is easily operated and maintained by semi-skilled labour.

Although the design of the Hydra-Cat is unique and sophisticated, care has been taken that on-site operation is easy and maintenance is kept to a minimum. All components of the system are 'standard' and spare parts are available world-wide.

The 'heart' of the system is a Graco King Hydra-Cat with a fixed volumetric mix ratio, driven by compressed air. It is capable of accurately and consistently proportioning any two component coatings at any one of a number of pre-specified volumetric mix ratios whilst maintaining pressures of up to 205 bar (3000 psi) and delivery rates of up to 10 litres per minute.

The machine can be built with any one of a number of ratios and it is a simple and inexpensive job to change from one ratio to another.

Ratios available as standard are:-

1:1, 1.25:1, 1.33:1, 1.5:1, 1.66:1, 2:1, 2.4:1, 2.5:1, 2.66:1, 3:1,3.2:1and 4:1.

Other ratios are available on request.

In order to overcome variances in ambient temperature and to accelerate the curing time of the mixed material, both the base and if necessary, the catalyst need to be heated. This is done in two separate, colour coded storage tanks each holding some 70 litres of each material. Each tank has its own material feed pump again air operated and with an output of up to 12 litres per minute.

These material storage tanks are each sealed into a second tank, the void between these inner and outer tanks being filled with a special heater oil. The oil temperature is raised by immersion heaters. Each tank has one 2.4 kW heater and one 1 kW heater. Depending on available power the unit is switchable to, high power i.e. 3.4 kW each tank or low pressure 1 kW each tank. Temperatures are thermostatically controlled.

Each tank has a 50mm (2") ball valve fitted in the base to facilitate rapid emptying should this be necessary. Pipework is also arranged from the base of a solvent tank (described later) to the Hyrda-Cat pump and valves are so arranged to stop the flow of base and catalyst and to introduce solvent into the Hydra-Cat pump so it and the hoses can be flushed without the need to empty the base and catalyst supply tanks.

Base and catalyst are fed from each storage tank via high volume filters and rigid pipework, which is lagged to minimise heat losses, directly to the inlet side of the Hydra-Cat pump.

The Hydra-Cat pump is thus receiving the base and catalyst at a constant temperature, viscosity and pressure.

The Hydra-Cat pump then accurately dispenses the base and catalyst at a fixed ratio by volume and pumps them under pressure via the colour coded, high pressure filters, into flexible high pressure hoses, which can, if ambient conditions warrant, be heated.

The hose 'families' are supplied in 15m (50ft) sections, each 'family' consisting of one hose for the base, one hose for the catalyst and one hose for the solvent. Internal diameters depend on the material but all hoses are high pressure and solvent resistant.

The hose family is fully insulated to minimise heat loss and the whole wrapped in a nylon, anti-scuff sheath.

There is no limit to the number of hose families that can be coupled together but pressure losses in hoses mean that for all practical purposes no more than 45m (150ft) in total can be used. Up to 105m (350ft) can be used, if hose families are also heated.

The hose family is then fed into a special manifold which has one combined valve to control the flow of catalyst and base whilst at the same time maintaining solvent under pressure, when the valve is reversed, base and catalyst stop flowing and solvent is then admitted.

The solvent for flushing is supplied by a 23:1 ratio air operated pump feeding from 25 litre tank of solvent mounted centrally on the machine, this tank also being fitted with a drain valve.

On leaving the manifold described above, the base and catalyst pass to a static mixer. Dependant once again on the material to be sprayed, these mixers are available in various lengths and element configurations and depending on the pot life of the material are mounted immediately after the mix manifold or immediately prior to the spray gun.

The spray gun, which can be any suitable airless spray gun is connected to or from the static mixer by a short length of H.P. solvent resistant hose.

Controls for the machine mounted on one side at eye level consist of two weatherproof cabinets each approximately 400mm (16") wide, 610mm (24") high and 229mm (9") deep. One houses the electrical controls for the heated tanks and heated hoses if fitted, the second houses all the air controls for the pumps.

All controls are simple to understand and operate and full wiring circuit diagrams are provided.

The whole assembly (as standard) is mounted on a four wheeled (two steerable) heavy duty cart with 406mm (16") diameter solid tyres. On request it can be built into other configurations such as on a pick-up truck, in a container or simply skid mounted.

The whole unit is approximately 1.82m (6') long, 1.06m (3'6") wide and 1.75m (5'9") high and weighs approximately 700 kg without the hose assemblies.

For efficient operation, compressed air and single phase 110v electricity is required and main connections for these are incorporated on the machine. Compressed air requirements are approximately 1.98 MPM at 6.8 bars(70 cfm at 100 psi), electrical requirements, 110v 75 amps.