90도 개폐로 조작시간이 매우 짧고 설치공간이 Gate 나 Globe밸브에 비해 적어도 된다.Ball이 Seatring에 의해 지지되는 구조로 저압이나 소형사이즈에 적용된다.Upstream 압력에 의해 Downstream 쪽으로 Ball이 밀려 Sealing 되는 구조이다.
■ GENERAL
KJS floating ball valves are designed in accordance with API 608 or ISO17292(BS5351) for ANSI Class rating 150 to 2500, Nominal size from 1/2” to 12”. Valves have been designed for use with various combinations of materials such as; Carbon Steel, Low Carbon steel, special alloy, stainless steel, monel, inconel.
■ BODY JOINT CONSTRUCTION
The one piece unibody end entry design, graphite ring or-oring viton (on request) seals ensure absolute seal integrity. The two piece bolted body designs include a tight toleranced overlapping metal fit between the body and the adapter to minimize any possibility of movement due to pipeline stress. A special high temperature spiral wound stainless steel/grafoil filled gasket is utilized for absolute seal. This gasket is encapsulated by body and adapted on all four sides. Body and adaptors are dimensioned for metal contact to ensure correct gasket crush.
■ BLOW-OUT PROOF STEM
Stem is made separately from the ball, anti blow-up design with suitable PTFE and graphite rings and antistaitc device. The lower and of the stem is designed with an integral collar to be blowout-proof. lt also functions as the backseat for assured stem sealing. (fig. A)
■ ANTI-STATIC DEVICE
All Flow Control floating flange ball valves include dual grounding systems from stem to ball and stem to body. Valve testing to ISO17292(BS5351) was perfomed for all sizes, and witnessed by a third party inspection company. An antistatic feature is provided to ensure electrical continuity for assured stem sealing. (fig. B)
■ LIVE LOADED GLAND FLANGE
Live loading is designed to provide gland load retention, compensating for expected in-service consolidation of the packing. A Set of Belleville-Spring Washers are used on each gland stud to helpexert a continuous compressive force on the gland follower flange and therefore reduce fugitive emissions from the stem packing. KJS standard Belleville-Spring Washers are protected by a weatherproof cap to keep them free from environmental contamination, resulting in a long stable life. (fig. C)
■ LOCKING DEVICE
Stem head design provides mounting of the lever handle always in parallel to the flow passage. Facility for mounting a locking device for prevention of accidental valve operation is provided. (fig. D)
■ FIRE SAFETY
All-fire-safe valves conform to API 607 and API 6FA standards. When fire accident occurs at valve operating jobsite, and components such as seat ring, stem back seat, stem packing and mid-flange gasket which made of non-metallic material such as PTFE were broken or destroyed. However, KJS particularly metal to metal added seal seated designed ball valves can effectively control external or internal leakage. KJS soft seated fire safety designed as follows:
■ LONGEVITY OF LIFE
Special consideration was devoted to the attainment of enhanced life and operation of our valve throughout design, development, testing and manufacturing stages. Valve designs combined with the selection of advanced materials are such that long periods of inactivity should not affect the operations of efficiency.
