The flange spacing of the external float level gauge does not match the flange spacing provided on the equipment; as a result, the flanges cannot be aligned during installation. What should be done?

Let me share the guidance I provided during the on-site construction: First, it’s clear that it’s not a connected-pipe solution; rather, it’s an issue with the flanges on the equipment itself, right? 1. If there is an obvious discrepancy in the spacing, for example, if 1700 was ordered but 1400 was used, it would be advisable to have the process engineering team recheck the locations that need to be measured. For example, it could be at the same level as the upper lip, or at the same level as the lower lip, or 150 for each. 1. A 90° elbow + short pipe is required. 2. In cases of obvious spacing errors, such as ordering a part with a specification of 1400 when it should be 1700, using two 90° elbows + short pipes will suffice. 3. Errors in equipment manufacturing, such as differences between 1700 and 1680, can only be addressed through on-site hot working: first remove the existing supports for the fixing fittings (if any), then use flanges + short pipes, and adjust the angle of the short pipes to match the required spacing between the instruments. Of course, the best solution from an instrumentation perspective is to place a new order. But if it’s a high-pressure device, well, haha, it’s not even possible to place a new order; it’s better to ask the design institute what to do. The above solutions are also viable, but one still can’t help feeling worried

What can be done? Either the original flange opening must be sealed off and the equipment manufacturer must reopen it after ensuring it meets the inspection requirements, or the instrument must be reordered. Any other approach taken for convenience is merely a temporary fix

See if it’s possible to install with the enlarged studs

Suggestion: If the distance between the flanges on the equipment is too small and it’s not possible to install the level gauge, cut away the flanges on the equipment and create new openings. This is more complicated in the case of pressure vessels, and it is necessary to inform the inspection agency. If the level gauge is too short, add a short circuit. After all, it’s rather troublesome to repurchase a level gauge.

I disagree with the opinion above. Making random holes in pressure vessels undermines their ability to withstand pressure. Is your company capable of conducting pressure tests on its own? Do you have the qualifications for welding and modification of pressure vessels? The boiler inspection agency will definitely not approve your inspection. Rebuying the level gauge is the compliant approach

First, is it the larger flange spacing of the float level gauge or the larger flange spacing reserved on the equipment? If the flange spacing of the level gauge is large and the tank being measured is not a pressure vessel, it can still be reconnected by adding flanges, short pipes, etc ； If the flange spacing reserved for the equipment is large, it will be necessary to purchase a new level gauge; otherwise, the portion of the volume that exceeds the range cannot be measured. It is recommended to purchase a new level gauge.

If the difference isn’t significant, it’s possible to have a domestic level gauge manufacturer conduct on-site measurements and then use a bypass to resolve the issue; if the difference is large, it will take only a few days to manufacture a new one