Bray Cryogenic User Manual

Page 4

Installation and Maintenance Manual

Multiport Threaded and Weld End Ball Valves

Date: August 2011 / Page 4 of 6

A Subsidiary of BRAY INTERNATIONAL, Inc.

FLOW-TEK, Inc.

Tel: 832.912.2300

8323 N. Eldridge Pkwy #100

Fax: 832.912.2301

Houston, Texas 77041

www.flow-tek.com

8. ASSEMBLY
½”-2” VALVE ASSEMBLY PROCEDURES:
Hold the body in a vise with the stem horizontally firmly

enough so it will not move but do not crush it.

EXTENDED STEM ASSEMBLY
Put thrust washer (3) on valve stem (2) and slide the

stem into the stem hole in the extended body (1);

Slide the stem packing components (4) onto the stem

until it is sealed against the bottom of the stem hole;

Put packing protector (5). then packing gland sleeve

(6) onto the stem and the top of the stem packing;

Install extension gasket (12) into the body recess and

insert the lower end of the stem into the valve body

stem hole.

Align the four mounting screw holes and install the

four mounting screws (10).

Tighten the four cap screws to the recommended

values in table 1.

VALVE ASSEMBLY
Turn the stem until the stem flat is parallel to the port

centerline (so that the ball can fit onto the stem).

Install one seat (18) and two body seals (19,20) into

the body (16), make sure the spherical curvature side

of the seat will face the ball;

Install the end cap (15) with cap screws (14) and

tighten screws to the values indicated in Table 1.

Rotate the stem to the closed position and install the

ball (17) inside the valve body. The stem flats will fit

into the slot on top of the ball;

Turn the stem so that the ball is in the open position

(the ball will not fall out of the valve);

Install the second seat (18) and two body seals

(19,20) inside the body (16), make sure the spherical

curvature side of the seat will face the ball;

Install the end cap (15) with cap screws (14) and

tighten screws to the values indicated in Table 1.

Put Belleville washer (7) together in series mode (bottom

Belleville washer curve facing up, the top Belleville

washer curve facing down). and then place them onto

the stem, on top of the packing gland sleeve;

Put tab washer (8) on top of the Belleville washer and

tighten the stem gland nut (9) onto the stem to the

required stem gland nut torque value as specified in

the chart.

(Note: The use of a bore alignment tool, about 1.0 mm

(0.04 inch) less than the internal diameter of the end

cap and ball, inserted through the end cap and ball

will prevent the ball from turning as the stem gland nut

is lightened on the stem.

Material for the bore alignment tool should be made

from a material softer than 300 Series S.S. so that it

will not inadvertently scratch the valve end cap or ball.

Suggested materials: Aluminum T6061. Acetal

or other hard polymer/plastic materials are also

suitable.)

Secure the tab washer with one ear bending up;

Place the handle (25) onto the stem, on top of the

stem gland nut (9);

Secure the handle (25) with the stem lock nut (9).

Table 1; Tightening torques for cap screws

VALVE SIZE

1/2”

3/4”

1”

1-1/4” 1-1/2”

2”

3”

4”

EXTENSION MTG

SCREWS (lb-in.)

150

550

BODY END CAP

SCREWS (lb-in)

140

210

550

996