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Month: January 2013

Hydraulic Pump Calculation

Rifka Aisyah Leave a comment

Yesterday I just finished doing hydraulic pump calculation for one of a project in my company. The purpose of the calculation was to determine suction pressure, discharge pressure, and pump differential head.

Pump calculation procedure is very simple.

First, you need to define pump operation condition. It includes fluid temperature, fluid specific gravity, fluid viscosity, pump normal capacity and design capacity.

Second, check your Piping and Instrumentation Diagram (P&ID) carefully. In this step you need to calculate pressure drop due to pipe line and fittings in the suction and discharge of pump. You need to list fittings and calculate pressure loss due to the fittings.

Total suction head = line loss + loss due to accessories + suction head

Do the same thing as for discharge head.

Differential head is calculated by this formula

Differential head = total discharge head – total suction head. 

 

Problems in Secondary Copper Smelter: Possible Causes and Alternative Solutions

Rifka Aisyah Leave a comment

Recently I learnt about secondary copper smelter, the problems raised due to the processes, and what alternative solutions are. The motive was very clear: I need to prepare for the upcoming project. As already describled here, a process engineer is responsible for the process during project preparation and project execution. And that’s exactly what I am doing right now. Read More

Sizing of UASB (Upflow Anaerobic Pond) for Wastewater Treatment Plant

Rifka Aisyah 1 Comment

I think this is my first time I learnt about Upflow Anaerobic Sludge Blanket (UASB). I’ve ever learnt about anaerobic wastewater treatment, however I don’t have any idea about UASB and what the differences are. Since I am responsible as engineer in wastewater treatment package, I need to learn about UASB (there is a possibility that this system will be included in the package).

What is Upflow Anaerobic Sludge Blanket? Read More

Understanding Terms in Piping System Part 1

Rifka Aisyah Leave a comment

You always need to find a bright side of a simple task. For example, copy, paste, and modify piping material specification, specification for coating and wrapping, and piping design. Yesterday I did this! At the first time I thought this was a very ridiculuous task yet unimportant. I’ve ever seen a drafter did this. But I found a bright side of this task which is a chance to learn. 

My objective is very simple. I want to understand what other people are talking about, when piping is their topic. I want to undestand the terms and imagine what they are looked like. That’s all. I think this is a good step to learn about piping.

Piping system has a lot of terms. So, it is impossible to write and describe all of them. In this post I want to share a brief explanation about piping system. As long as I understand them, it’s oke 🙂 Read More

Why do we need to make complete technical bid tabulation, requisition, or data sheet?

Rifka Aisyah Leave a comment

Now I undestand. People said experience is the best teacher. I think that’s true.

I have already follow procurement of several equipment package since the beginning. I compared my preparation and others (especially preparation of engineers from our head company). My preparation was way way incomplete. I felt the effect right now.

One of my colleague asked me if the internal of pressure vessel in water treatment plant will be spark tested or not. The purpose of spark testing is to determine if there are leaks in the rubber lining and identify the locations. It is a mandatory test in rubber lining tanks.

So, what is the problem? The problem is, for any reason, the appointed vendor cannot perform the test. They just give us the guarantee that there will be no leaks in the lining.

I have googled and found that some vendors perform pre- and post-cure inspection for rubber linings. I got to understand that the test was very important.

Back to the topic. I wish I could turn back time and wrote on my technical bid tabulation and requisition, and data sheet about the point. I did not have spend time to focus in such details. That’s something which is not our concern at the beginning and at the last it became a problem.

Lesson learnt: be detail in making technical bid tabulation. Consider many factors. Ask your colleague or somone who has more experience than you. 

Where to install pressure gauge at pump discharge line

Rifka Aisyah Leave a comment

Yesterday I had enough time to increase my basic knowledge in chemical engineering because I had finished my works. Then, I stumbled upon this link and started to think about my piping and instrumentation diagram. I realized I had make a fundamental mistakes. I felt useless.

I am writing this post so that I will remember my mistakes and never try to do it again. Hope you find it useful.

Remember everyone! Pressure gauge shall be installed after pump discharge nozzle and before check valve. The consequence is if you have two pumps (one is running and another is stand by, then you have to install two pressure gauge). The reason is:

  • To show actual pump discharge pressure. If you install pressure gauge after check valve, the value of discharge pressure won’t be actual due to pressure loss of check valve
  • In the case of check valve failure, pressure gauge will show actual discharge pressure. If the pump has problem, pressure gauge will show pressure value lower than usual

Discussing about Fire Extinguisher with Vendors

Rifka Aisyah Leave a comment

Yesterday I got a quite tough and long discussion with one of fire extinguisher product vendor. I learned that I need to define what I really want, what scope of supply is, and what scope of works is. The discussion became very unefficient at the beginning because of those issues. My action was late so that I could not control the discussion. Fortunately, it was clear at the end.

I have created material take off for fire extinguisher and other related products, such as hose reel, potable fire extinguisher, manual alarm pull station, smoke detector, hydrant pillar, hydrant box, siamese connection, and water spray for the tanks. However, there were several issues that has not been addressed. Honestly, the discussion broadened my knowledge because the vendor has a lot of experience (I think). In this post, I want to share to you some of the points. Read More