Environmental regulations are increasingly stringent throughout Australia. The ability to contain contaminated waterways is a common issue in all industries. The AWMA PosiSeal will ensure compliance can be achieved with custom designed Penstocks that are economical and fast to install.
Common requests for 100% sealing include situations with high head differential and spill containment (to prevent downstream contamination).
The AWMA PosiSeal provides 100% seal with heads up to 10metres. The penstock can be headwall mounted or attached to the end of poly, concrete or steel pipe works. Some installations on new structures have cast the PosiSeal gate into the structure.
The 'PosiSeal' Positive Seal Valve can be constructed from stainless steel or marine grade aluminium.
A unique feature of the AWMA PosiSeal is the guidance system on the gate. The gate is guided on completely plastic (UHMWPE) 'bullet' guides in plastic runners.
This type of penstock usually uses round bearings on the gate, in steel guides. The UHMWPE 'bullet' guides spread the load across a broad surface preventing full load on "point contact", as occurs with bearings in steel guides.
The plastic 'bullets' do not rotate and have a very low friction, co-efficient design, so they do not require maintenance.
The PosiSeal penstock gate is as large as the orifice requires. The penstock can have a frame of any size, with a specified height to allow an actuation system from the top of any structure. The gate may have manual or automated control.
PosiSeal gates are suitable in all applications requiring a quality penstock with 100% seal.
The PosiSeal is usually manufactured for round orifices, but has also been custom designed for square and rectangle openings on culverts.
PosiSeals are designed for fast and economical retrofits to existing structures without the need for civil works, thus reducing overall costs.
The PosiSeal usually incorporates a non-rising spindle reducing infrastructure above the waterline. This type of penstock also provides full orifice opening giving a totally unobstructed water way.
All PosiSeals are custom designed to suit specific requirements. To date the PosiSeals have been manufactured from 150mm to 1800mm diameter, as well as numerous culvert sizes.
PosiSeals were recently required for the Newport Power Station on the Yarra River in Melbourne. Rectangle PosiSeals were used to facilitate a 100% seal, from their storm water system to the river. The two gates were fitted with pneumatic rams enabling fast actuation (less than 10 seconds) to close the gates should a spill occur. The PosiSeal was retrofitted to an existing culvert by the AWMA installation team without the need for civil works to modify the site.