APV DELTA DA3+ SLD, Operating Manual

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9
UK
DELTA DA3SLD-UK0.qxp / 12.2007
Double Seat Mixproof Valve with Seat Lift Detection
DELTA DA3+SLD
Operating Manual: Rev. 0
6. Installation
- The valve must be installed in vertical position. Fluids are, therefore,
freely drainable from the valve housing and the leakage chamber.
- Valve housings can be welded direct into the pipelines (completely
dismantable valve insert).
- Attention: Observe welding instructions.
- Heights of installation and dismantling (see section 7).
6.1 Welding Instructions
DA3+
- Before welding of the valve, the valve insert must be dismantled
from the housing. Careful handling to avoid damage to the parts is
necessary (see 11.1).
It is not necessary to remove the lower shaft seal as it can be
destroyed during dismantling.
- Welding should only be carried out by certified welders (EN 287-1).
(Seam quality EN 25817 "B").
- The welding of the valve housings must be undertaken in such a
way that the valve body is not deformed.
- The preparation of the weld seam up to 3 mm thickness must be
carried out as a square butt joint without air. (Consider shrinkage!)
- TIG orbital welding is best!
- After welding of the valve housing or of the mating flanges and after
work at the pipelines, the corresponding parts of the installation and
pipelines must be cleaned from welding residues and soiling before
operation of the valves to avoid damage to the valves and seals.
If these cleaning instructions are not observed, welding residues
and dirt particles can settle in the valve and cause damage.
- Any damage resulting from the non-observance of these welding
instructions is not subject to our guarantee.