Class 800 Regular Pattern

AUDCO SUPER-H Pressure Balanced Plu» Valves have been developed to reduce the operating torque in plug valves without compromising uu thu in-line maintenance capability. The plug and bcKiy seating surfaces, which are lapped and matched, are not exposed to the line fluid while valves are in open condition; this confines corrosion and erosion to less critical areas. Scaling is further enhanced by specially developed plug sealants charged evenly around the seating surfaces* The plug is impregnated with PTFK based anti-friction agent – ‘SUPKR LoMu’ - which provides greater wear resistance and ensures consistent operating torque


           SUPER LoMu

In a standard taper plug valve, the line fluid finds iis way into (he large end chamber of the plug. The resultant force pushes the plug into its taper scat causing taper locking and possibly valve seizure. This resultant force persists when the subsequent line pressure remains high or is reduced. To unseal the taper locking and keep the valve operational, frequent sealant injection is required. In pressure balanced plug valve pressure balancing is achieved by providing two holes in the plug connecting the chambers at each end of the plug. The chambers, one fitted with a non¬return valve acts as a balancing mechanism for the plug. The pressure in the large end chamber always equals line pressure and the pressure

Plug and Stem of Supcr-H Pressure Balanced plug valves are treated with an antifriction agent based on PTFE which wc call as "Super LoMu". This provides greater wear resistance and ensures low consistent operating torque
Supcr-H Pressure Balanced Plug valves of class 800 are intrinsically fire safe by design. The features incorporated in the valve make the valves seal and operate effectively even after being subjected to fire of varying temperatures and duration resembling fire accidents
Valve Design BS 5353
End to End dimensions ASME/ANSI BI6.10
and BS 2080
Socketweld ends ASME/ANSI BI6.11
Inspection & Testing BS 6755 Part 1
Super-H Pressure Balanced Plug valves generally need very little attention on installation. However, lor trouble free operation sealant injection as recommended is to be carried out Please refer to "Installation. Operation & Maintenance Manual of Supcr-H Pressure Balanced Plug valves" for details.

As a standard. Supcr-H Pressure Balanced Plug valves are supplied with AUDCO 733 Plug Sealant suitable for most hydrocarbon services in a temperature range of-40 to 480° l\ On request, plug sealant from a wide range offered* can be supplied to suit the nature of service. It is recommended that you consult us before selecting the plug sealant for a new service.

in the small end chamber is always equal to or greater than the line pressure, minimising the resultant force. Pressure balancing eliminates out ol balance forces and consequent taper locking. The Figure shows clearly how a balanced position is reached when line pressure is allowed to equalise the pressure acting on each end of the plug

Name of pan Specification
 ASTM A 105
 AS'I M A 216 Gr .WCB for 40mm
Plug  BS970 0SOMI5
 BS 970 070M20
 ASTM A 216 GrWCB for 40mm
Packing  Graphite
Max. CWP
at-20 lo I00T
Shell Seal
psig bar psig bar psig bar
CI. 800 1975 136 3000 207 2175 150
    DIMENSIONS (Inches / mm)                                                                                             
Size Pattern A B C D E Wrench
Inch mm
1/4 15 R 89 21.97
10 104 76 B8 230
3/2 20 R 133 27.31
13 127 97 B9 318
1 25 R 133 33.78
13 127 97 B9 318
1.1/2 40 R 228 48.65
13 180 120 B5S 685


A familiarity with our catalogue number is nut necessary when specifying or ordering our valves. If full description of the valve could be provided we will translate this into a catalogue number formulated as per the following system.