GE ApexPro T9, Руководство по установке

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Chapter 2. Installing Pipe Nozzles
14 Model T9 Ultrasonic Flow Transducer Installation Guide
2.6 Installing the First Nozzle (cont.)
5. The jig, boss, and nozzle combination is designed to provide a 0.094 in. (2.4 mm) root gap between the beveled
edge of the nozzle and the outside diameter of the pipe. If the 0.094 in.
(2.4 mm) clearance does not exist all around, the nozzle must be removed and ground appropriately to provide the
required clearance. If the root gap is larger than the 0.094 in. (2.4 mm) dimension, then suitably sized washers may
be inserted between the jig and the nozzle in order to reduce the root gap dimension.
WARNING! ONLY QUALIFIED PERSONNEL SHOULD WELD BOSSES AND NOZZLES, USING A SUITABLE ASME IX
QUALIFIED WELDING PROCEDURE.
6. Tack weld the nozzle to the pipe at four diametrically opposed points, each tack being approximately 0.6 in. (15
mm) in length. Allow to cool for 30 seconds between tacks.
7. Proceed to complete the root pass and subsequent filler passes as required.
8. Allow to cool, then remove the threaded rod, washer, nut, and jig.
2.7 Installing the Second Welding Boss and Nozzle
Install the second welding boss and nozzle at the required position as described in Installing the First Welding Boss and
Installing the First Nozzle beginning on page 10 . The completed installation should appear as shown below.
2.8 Hot Tapping the Pipe
WARNING! HOT TAPPING SHOULD BE PERFORMED ONLY BY QUALIFIED PERSONNEL. FOLLOW ALL
APPLICABLE CODE AND SAFETY PRACTICES DURING THESE PROCEDURES.
1. Install 3 in. ANSI flanged full-bore isolation valves on both nozzles (8 in. face-to-face for 150#RF or 11.125 in. for
300#RF) with gasket and 5/8-in. diameter studs and nuts. Orient valve handles to minimize interference.
2. Hot tap holes in the pipe using hot tap machine equipped with a 3/4 in. (19 mm) drill bit. Then use a coupon
retaining hole saw to cut a hole a minimum diameter of 2.36 in. (60 mm).
Flow