[Johannesburg, 05 July 2016]: Leading supplier of high-end and specialised equipment to the oil and gas industries in Southern Africa, Energas Technologies is proud to introduce Protectoseal’s new Series 10 2” Tank Blanketing Valve to the South African market.
Tank blanketing is an important and effective way to prevent fires in flammable liquid storage tanks by controlling the formation of explosive vapours or air mixtures. Blanketing minimises evaporation of the stored product, in so doing, reducing emission levels and product loss. It also protects the tank’s contents from external contamination.
Comments Laetitia Botha, Energas Technologies Product Engineer, “Tank blanketing has always been a staple in our range of safety products. It works on the basic principal of creating a blanket of inert gas in the tank’s vapour space to prevent atmospheric air from entering the tank, and so maintaining a non-flammable atmosphere.” She adds, “We’ve stocked Protectoseal products for 10 years and bringing in the new Series 10 2” Tank Blanketing Valve was a great way for us to offer what the Series 20 1” could not provide for larger flow applications.”
How it works
A blanketing valve regulates the pressure of the inert gas layer on top of the stored liquid in a tank. The valve senses the pressure of the tank blanket and opens to allow in more inert gas when the pressure drops below the set pressure. In response to the pressure then building back up to the set pressure, the valve closes and stops the flow.
The Protectoseal Series 10 Tank Blanketing Valve comprises two separate valves working in tandem. “The pilot valve is controlled by the sensed tank pressure, and, in turn, controls the opening and closing of the main valve, which provides flow into the tank from the inert gas supply,” explains Botha. “The main components of the pilot valve are a pressure sending chamber and a poppet, which can move up and down. The main valve, on the other hand, has a piston which can move to control flow into the tank,” she adds.
When the flow of gas into the tank increases the tank pressure above the set pressure, the sense diaphragm is pushed up, allowing both the stop and the poppet to rise (made possible by the spring force under the poppet) until the poppet reseals. Once this has happened, the dome pressure is then allowed to build back up to the inlet pressure, pushing the piston closed once more, which ultimately shuts off flow to the tank.
Features & benefits
The Protectoseal Series 10 2” Tank Blanketing Valve has a host of features and benefits. The valve is specifically designed for tank blanketing and its pilot-operated design offers a very tight operating band. It boasts the most compact design and fewest external connections of any other pilot-operated valve on the market. It is also field serviceable.
“The valve is available in a range of a materials,” says Botha, adding, “The metal parts are available in 316 stainless steel and the seals and gaskets are available in Buna-N, Neo prene, Viton®, EPDM, Chemraz® or Kalrez®. The inlet and outlet connections of the Protectoseal Series 10 are available in many threaded (FNPT, DN PN16, DN PN10), and flanged (ANSI, DN, FF, RF) combinations. The Series 10 conforms to the latest European ATEX Directive. In the case of applications involving high purity products, Protectoseal Pure-Tech High Purity Blanket Valves are available.”
The Series 10 offers two special options, namely status port and single port sensing options. The status port option is primarily use in remote areas and gives an indication of the open vs. closed status of the valve. It offers remote monitoring via pressure transmitter, sounds an alarm when blanketing gas flow is excessive and reduces operating costs by allowing monitoring of blanking gas usage.
The single port sensing option boasts single connection mounting, eliminates the need for a separate sense-like connection to the tank and efficiently controls tank pressure.
“Protectoseal is the industry leading manufacturer of environmentally sensitive safety products and an important supplier to Energas Technologies’ range of products,” Botha remarks. “By offering its latest in tank blanketing valve technology, we are able to offer our customers not only a safety-enhancing product, but one that facilitates operational efficiency and minimises wastage. We’re delighted to bring Protectoseal’s ‘big brother’ in tank blanketing to South Africa and look forward to facilitating and supporting its successful uptake in this market,” she concludes.