Case Studies

Highly corrosive slurry

BI-SEAL has been manufacturing the Tytan knife gate valve for a number of highly corrosive services.

BI-SEAL’s has been using Titanium grade 12 for the Tytan.

Please note: the valve has been designed, machined and tested in Australia.

Highly abrasive slurries

For particularly abrasive slurries a hardened tool steel knife gate valve may be the most appropriate choice of knife gate valve. Please consider other elements such as ph levels for example before choosing a knife gate valve

"Repacking of a Knife gate valve appears straightforward, but is frequently done incorrectly"

Prior to repacking the Knife gate valve is disassembled

Valve Disassembly procedure

1. Close valve.
2. Disconnect clevis.
3. Remove yoke assembly.
4. Using a packing hook, remove all of the old packing.
5. Carefully clean the stuffing box. Do not use a solvent to clean the stuffing box in rubber-lined versions of BI-SEAL valves.

"Ensuring the packing is longer than the appature is one of the keys to eliminating leaks in the stuffing box"

Cut each length individually making a square cut with a clean, sharp knife.

• Cut packing as follows for 50 mm – 300 mm NB valves = stuffing box length + 5 mm
• Cut packing as follows for 350 mm-750mm NB Valves = stuffing box length + 10mm (90 degree cuts gives the packing the best chance of sealing end on end.)
• For brick style packing assemblies cut the short lengths stuffing box width +2mm

Ensuring the packing is longer than the appature is one of the keys to eliminating leaks in the stuffing box

1. Install the packing in both sides of the gate one row at a time. Feed the ends into the stuffing box.
2. Use the flat bar and hammer to tamp the packing into position, working from the centre outwards
3. Repeat for each layer of packing.
4. Re-assemble packing gland and yoke assembly

IMPORTANT!! Do not take up gland follower bolts more than is necessary.

When installing packing assemblies in Knife gate valves the most important part of the procedure is the tamping of the packing. Incorrect tamping may result in costly and dangerous leaking.

The secret to good knife gate valve packing is to tamp each row into place. Please note: trying to pack your valve solely using the gland follower to compress the packing will result in a leak. This will place an undue requirement of force on the gland follower bolts trying to achieve a leak free situation.

Still having issues with corrosion resistance ?

As mining has gone deeper into ore bodies their chemical composition has changed. This has caused increased corrosion and its associated costs.
Extensive testing of metal alloy combinations has yielded titanium alloys as the most resistant to chemical deterioration in highly corrosive, high chloride ore bodies.

• The new TYTAN range is Australia’s only designed and manufactured TITANIUM knife gate valve.
• TITANIUM has remarkable corrosion resistance, particularly in high chloride environments.
• The TYTAN has the same proven design as the existing range of Knife Gate Valves

BI-SEAL continue to manufacture in Australia by choice. It’s the best way to listen to our customers and solve their challenges.  

Super Duplex O-PORT Valves

• 10 years ago BI-SEAL Australia were approached by an international fertiliser company to design and manufacture super duplex (UNS32750) O-Port Valves. The valves were for the main reactor service. The valves in service were failing, often at considerable expense to the operation.

• O-Port Valves were designed manufactured by BI-SEAL and placed in service. 10 years later the same valves are still in service today.

• The O-Port Valves ranged in size from 200mm to 750mm.

Continuity of Service at Gold Mines

Gold Mining Companies prefer BI-SEAL FRP knife gate valves (field replaceable parts) in many applications such as:

• Cyclone application valves.

• Paste fill tailings distribution.

• Paste fill elution and dilution columns,

• Mill water.

• Discharge return circuits and many other applications.

Preference is given to BI-SEAL valves due to the opportunity to field replaceable parts as seen below. The remaining parts of the valve body are retained and used for many years.

BI-SEAL valves are bubble tight in both directions - BI-SEAL valves are bi-directional.

Please note this valve was previously known as the VTM Knife gate valve. In fact to this day all the knife gate valves bodies are cast (all within Australia) as 'VTM Australia' To finally clarify the VTM FRP Knife gate and the BI-SEAL Ferro FRP are exactly the same valve.

High Pressure Acid Leach Processing

BI-SEAL Australia have established an international reputation for it's range of alloy valves in:

• Duplex (UNS S32205),

• Super Duplex (UNS 32750)

• Hastelloy (C276)

in high pressure acid leach (HPAL) processing in nickel cobalt and gold mines.

Blower isolation in Acid Plant

BI-SEAL designed and manufactured a 1200mm Fabricated Valve.

• For Blower Isolation in Acid plant at a HPAL (High pressure acid leach) Facility.

• Fabricated 316 stainless steel body.

• Pneumatically operated actuator.

Pregnant Leach Solutions

BI-SEAL have Super Duplex (UNS 32750) valves in pregnant leach solutions with outstanding performance records. Some valves are still in service after ten or more years in:

• Uranium oxide mining

• Bubble tight isolation on PLS pump suction and discharge