Cast Steel Globe Valve[Bolted Bonnet]

YOKE BUSH
The standard material of the Yoke Sleeve is Nodular Ni-resist D2 with over a 1150°C(2100°F) dissolution point in conformity with API Std. Specifications.

BOLTING
The body-bonnet bolts are manufactured in accordance with API Std. 600 specifications. The nuts also srictly conform with ANSI B1.1 The stud-bolt nuts, hexagonal, rigid and hot-forged, bear material notation as well as do the bolt nuts made according to ANSI B18.2.2

BONNET
The bonnet is integral or separate with yoke and is the same material as the body. The body-bonnet flange drilling is spot-faced to exactly meet stud bolt nuts. The back seat bushing in the bonnet guarantees that the packing can be replaced even when the valve is fully opened. The stem packing dimensions of the stuffing box are in accordance with API specifications.

STEM
The heat-treated stems of one-piece construction insure adequate mechanical properties and surface hardness. Friction at the time of opening and shutting is reduced to a minimum friction to accurate machining and lapping. The round finished surfface of the stem heat helps to achieve point contact with the inside of the disc housing to eliminate friction.

SEAT RING
The shoulder seated type seatring is welded or screwed into body. The seating surface is finished by lapping. The seatring is forged and heat-treated to deliver the best mechanical properties and required hardness. The difference in hardness between the seats and disc conforms to API Std. specificatins.

DISC
The disc of our globe valves is a loose disc and can freely revolve around the stem. The prevents friction and galling with the seating surface when the valve is shut. The disc is furnished with a conical seating surface that has been ground and lapped to a mirror finish. It is of one-piece construction, and forged and heat-treated to deliver the required mechanical properties and hardness.

BODY
The cast steel body is designed to insure a wall thickness which is greater at any point than the minimum specified by API Std. 600. Port and seat passage dimensions conform to ANSI B16.5 Pipe Fitting. The screw-in type seatring is standard to allow interchangeability. The standard body-bonnet joint is male-female, and the flange is round for all valves, Accurate maching insures perfact coaxiality of the vale ends and seatring in addition to exact perpendiculatiry of the body-bonnet flanges.