BELLS ENGINEERING PRODUCTS
The details below act as a reference guide to assist with the selection of valves in industrial applications.
This is not intended to be a complete guide and our engineers can assist you will specific requirements of your application.
- Gate valves should be left in the fully open or closed position for long periods of time to assure satisfactory operation.
- Fine control or throttling can induce serious gate erosion.
- Suitable for use with water, gas and chemical duties.
- Overhead clearance for high stern, high lift valves is needed for installation and maintenance.
- Not suitable for service with heavy solids in suspension.
- Ideal as steam valves used as stop and control valves.
- They are not generally suitable for handling virulent sluggish, slurry type liquids not noxious/toxic gases due to the flow and difficulty of providing an effectively packed gland.
- For high pressure / high temperature services.
- Wide choices of material and size range.
- Generally low torque, low pressure drop and simple valve action.
- Not suitable for abrasive duties, high sterility requirements, coagulating fluids and throttling applications.
- The rapid acting valves are available with either taper or parallel plugs.
- They offer a very full capacity and streamlined flow in the open position.
- For effective operation lubricant under pressure is injected between the plug face and body seat.
- PTFE lined sleeves can be fitted to negate the requirement for lubrication.
- Pressure loss is minimal and high pressure easily handled with both liquids and gases.
- Different valve types are available where product purity, solids handling or a choice of materials/linings are required.
- A wide choice of basic body/disc materials is readily available with linings ranging from natural rubber to PTFE.
- Excellent for systems requiring a lightweight compact unit which is equally good, in general terms, for on-off and regulation work.
- Large/heavy solids services should be avoided; as should too-rapid disc operation.
- Suitable for on-off, throttling, pressure and high vacuum, air or hazardous chemicals. Maintenance is practically nil.
- Not a high temperature valve.
- ‘Straight-through’ versions are available.
- Unsuitable for high pressure lines wherever instantaneous closure or opening when required.
- Pinch valves are probably the simplest and most efficient valves available.
- They comprise a rubber hose or sleeve which is clamped in a pipeline and pinched or squeezed together to stop or control the flow.
- Fully open, the valve is similar to rubber lined pipe.
- In the fully open or fully closed positions there is little or no wear.
- A closed pinch valve should seal bubble tight.
- They are mainly used where abrasion, sewerage, solids handling and/or corrosion is a factor. They are the ideal slurry valve and have many advantages over other types of valves in these conditions.