Double Block & Bleed Parallel Slide Gate Valve

1.HANDWHEEL The spoked handwheel is fabricated from steel pipe. The hub is coupled with the yoke sleeve by means of a tongue.

2.YOKE SLEEVE The yoke sleeve is made from cast aluminium bronze having high resistance to wear and a high melting point. It is designed to permit removal from the bonnet or the yoke whilst the valve is in service. Gate valves 6″ class 600 and above are fitted ball thrust bearings.

3.GLAND AND FLANGE They are in forged steel and are supplied in two pieces, self-aligning design to permit the gland to descend parallel to the stem even if the eyebolts are unevenly tightened.

4.GLAND BOLTS AND NUTS The forged steel gland bolts are of the eyebolt type which can be swung outward for ease of gland repacking. They are fixed to the bonnet by hinge pins.

5.BONNET BOLTING Bonnet studs and nuts are manufactured from alloy steel to the relevant ASTM standard.

6.BODY The body is in cast steel and is carefully designed in all its details. The basic dimension, i.e. wall thickness, face to face and flanges comply with the relevant API and ANSI standards. The body-to-bonnet flange is circular, expect in the Class 150 which is oval. The body-to-bonnet joint are flat face on Class 150 valves, male-and-female on Class 300 and ring joint on Class 400 and above. The body is threaded for renewable seats. Bosses are provided for drain taps or by-pass piping.

7.BONNET The bonnet is in cast steel. It is machined to accept yoke sleeve and incorporates a stuffing box dimensioned in accordance with the API standard.

8.BONNET BUSHING The bonnet bushing or backseats is in forged stainless and forms part of the trim. Special attention is given to its machining.

9.STEM The stem is in forged stainless steel and is part of the trim. The stem is provided with a T head. A ground backseat is provided to ensure a perfectly tight seal to the stuffing box when the valve is fully open. The stem is ground to minimize friction and prevent damage to gland packing. The threading is trapezoidal ACME type. Dimensions comply with the API 600 standard.

10.SEAT RINGS The rings are in forged stainless and are part of the trim. They are completely threaded outsider and notched on their inner surface to ease installing and dismantling. Special attention is given to the sealing surface which are ground and lapped for a perfectly seal. Welded-in-seat rings may be supplied upon request.

11.PARALLEL DISCS The inclined plane mounted between the two disks converts downward stem force into axial force and presses the parallel disks firmly against the valve seats sealing the two openings. The central carrier provides strenght to the stem and the transmission of the torque steal.

BELLEVILLE SPRINGS Belleville springs packing ensures rapid unseating during opening operation.

REMARKS: A lantern ring is furnished only on request; in this case the stuffing box shall be tapped and fitted with an NPS 1/4 plug.

SAFETY RELIEF: is furnished as standard feature.