INTEGRATED STEM AND BONNET DESIGN
The stem and bonnet assembly presents a number of balanced features integrated in such a way as to provide improvement in stem operation, service life, and overall safety.
All stems are 316 stainless steel for corrosion resistance and longer life.
Stem threads are located above the stem sealing area so they are protected against contamination from the flow, again contributing to smoother operation and longer life. The thread area is lubricated at the factory, and the stem seal prevents washout of the lubricant, making for a permanently lubricated valve.
The stem threads are rolled for smoother operation and longer life. Note also that the stem and bonnet bearing area is larger than normally encountered. This makes for more precise stem alignment and gives a “superb quality feel” of operation, and it enhances overall seal ability.
An O-ring provides the primary stem sealing with a back-up ring providing lower friction, longer seal life, and a permanently adjusted stem seal arrangement. The color coded plastic stem protector keeps external contamination out of the thread area.
The thick cross sectional area limits and cushions downward handle movement, helping to prevent overtightening of the stem.
The stainless steel bonnet shroud fits over the hex wrench flats of the bonnet and secures it into position to impede loosening by vibration or other undetected causes.
The bonnet also contains an O-ring seal above the threads. Because these threads are not tapered, forcible removal of the bonnet would result in early blow-out of the O-ring and immediate leakage, warning against further removal of the bonnet. Conventional designs with tapered threads and no O-ring would not give warning of an impending blowout.
No other needle valve on the market today provides such a complete and rational approach to solving existing operational and safety concerns.
ADVANCE SEALING CONCEPT
Balon’s exclusive seat design is a split two-piece design consisting of two counter positioned conical sections. This arrangement provides independent bidirectional sealing. On closing, downward movement of sealing plug transmits force radially. Each seat section “floats” laterally, slightly promoting self-compensation for wear, as well as resistance to distortion, scoring, binding and permanent set, all common maladies of needle valves in general. Since each seat section responds to the cleaving effect of the sealing plug, bubble tight sealing occurs early, with less stem torque required than in other designs.
The split seat configuration preempts seat fracturing, a common cause of valve leakage. Two seats acting separately but also in concert, offer higher integrity sealing and extended service life.
Integral lugs on bottom of each seat section lock into matching recesses in the valve body. Seat rotation is denied. Alignment is assured and consistently maintained.
The Balon concept is not merely an answer to needle valve sealing problems, it constitutes a continued effort to raise the threshold of quality and lower the cost of ownership.
