As- built mechanical and electrical engineering drawings

Do you mean the importance...?

Assuming you do: There are very often small but important modifications made to the original design drawings when a system is assembled, tested, installed and commissioned. It is vitally important for future support of the client's system that these modifications are documented in the as-built drawing set which the client has access to - whether support is given by the original supplier, the client or a third party.

To expand on JohnDG's comment, here are some reasons a client may wish you long-life if you adequately document your as-builts and redlines:

Future modifications will cost less, if the baseline is as-built, instead of merely as planned

Such details as signal cross connects, or frame and chassis wiring, cannot be modified safely without complete knowledge of their current state. Again, this is as-built.

Designs almost always run afoul of the real world in initial assembly, one-off, first-article prototyping, and other small-run, early production stages. These necessitate changes to the design. If they are properly documented, later large-scale production runs can be bulit to the "this is how it really works" drawings, instead of the "this is how I thought it would work, but now I have to move/modify/machine this part to make it right". Believe me, when you hand-build 100 complex racks of equipment, housing dual, hot standby, computers, with peripherals and patch-panels, cableing, jack-fields, etc., and you don't capture the redlines on the first article, and convert your drawings from working to as-built, BEFORE building the second and subsequent racks, you'll spend huge amounts of schedule and money fixing every rack before you are done. Document it right the first time, and your customer will save many dollars, and headaches, down the trail.

And while I kept all of this in the hardware field, it holds even more true for software, or firmware, development. After all, if the bolt doesn't fit the hole in a hardware project, its is obvious quickly. But if the firmware, or software, has a glitch, and the fix is not documented, you'll deliver a lot of systems or apps before they ALL start costing your customer at once.

And in electrical or plumbing projects, no one gets invited back to do another project after the first showers, whether of sparks OR water.

So, document all fixes, redline all drawings, issue as-builts at the final turnover of the project.

Then wait to be invited back to do another one.

Been there, done that. Didn't always get to make a return engagement.

Micah

I agree with the two previous comments. I work for an engineering design house, and there are few things more frustrating than to design modifications to a plant when none of the existing drawings reflect the current state of affairs. It results in added engineering and draughting manhours, additional site work by contractors, and even unplanned plant shutdowns. Please spend a bit more time to issue as-built drawings at the end of a project as this will be more than paid for in future savings.

Generally I have noticed when a company gives contract for manufacturing an assembly or sub-assembly as per it's drawings, the vendor does not make note of modifications made intentionally or otherwise as he has take the approval and answer many queries each time from the company. So, the end-user may not get as-built drawings at all.

adegbyte, as micahd02 (post #2) pointed out and a number of others the cost for future modifications/upgrades will be reduced, also maintaining the equipment becomes that much more difficult.

I am currently doing some contract work for a company and I will spend the next month or two trying to get a proper set of as built drawings and there is no guarantee that I will get it 100% correct - and guess who has to pay for this, yes the customer. Had they ensured that the drawings were updated then they would not incur these costs and the project would be able to go ahead that bit sooner.

Kind Regards

Mr. W.A Snow

As-builts are also vital for first responders in facility emergencies. The fire safety or emergency plan should reflect accurate floor layouts and locations of life safety devices including electrical, gas and water shut-offs.

As a client/end user responsible for the operation and maintenance of a wide variety of equipment, I could tell you many horror stories of trying to diagnose and repair a fault when the drawings are not right. I have also seen equipment operators assume that the factory drawings were correct and cause thousands of dollars in damages. In addition to drawings, operating manuals often require revision following commissioning of a project to provide accurate procedures.

ALL of my purchase contracts require accurate as-built drawings, verified on site, before releasing final payment. That applies whether the item is $1,000 or $1,000,000. It is then my responsibility to ensure that any modifications later in the life of the equipment get properly recorded on the drawings.

As-built drawings are an essential item in the shipbuilding industry. Those drawings become an on-board part of the ship's maintenance plan. When you are in the middle of the ocean, one needs to know the actual circuitry or mechanical system so repairs can be done. Especially true for military ships.

As far as I have seen, in shipping industry rarely the plans are altered when carrying our repairs / alterations / modifications, especially in urgency / emergency. I usually see the purchaser coming with old / damaged spares in hand for replacement, instead of drawings.

I fully agree that it is important to maintain and update as-built drawings to reduce efforts, time and costs of maintenance, repairs and retrofits. But, it is difficult and in many cases may not be feasible to monitor modifications in case of capital goods and plant design.

In the case of military ships, "as-built" drawings are a mandatory part of the shipbuilding contract. On older ships, A team would visit the ship and check existing drawings against the ship. Then back to the office to prepare mod drawings. Sometimes the drawings look like the ship, other times, much different. Navy ships get mods and repairs all over the world and even by ship personnel themselves. When a ship that has last had a major overhaul 5+ years ago, It is expected that existing plans won't look like the ship. But when the job has been completed, an as-built drawing goes with the ship. One clarification; Only drawings that pertain to ship's systems are included. Basic structural drawings are not, as they are not part of a maintenance program.