Past simple in a report

Dear ALL,

I have to make a report about problem of a quipment which happened in past, the report is:

Coarse filter problem report

We have 2 coarse filters (filter 1 and filter 2), each filter contains a basket inside, they are using in water injection system for filtering particle more than 75u. Operation mode is one duty and one standby.
the day before, filter 1 online and filter 2 offline.
day 1: as normal operation, we opened filter 2 for inspection and found basket filter burst then replaced by new basket.
day 2: lined up filter 1 and isolated filter 2 due to high DP.
day 3: lined up filter 2 and isolated filter 1 due to basket burst after backwash sequence failed to cause high DP across filter.
day 4: lined up filter 1 without basket inside and isolated filter 2 due to high DP again even manually started backwash motor for running continuously.
day 5: we decided to change out another new basket for filter 2 and taken out existing one for chemical cleaning.
after this step, filter 2 is online with another new basket and can handle with normal water flow through filter and backwash sequence in auto mode as normal but DP across filter get high alarm in 4 minutes after backwash stopped.
day 6: we decided install new basket which was cleaned by chemical into filter 1 then put both filter online in parallel for sharing water flow into both flters.
with both filters online, DP indicates in range with backwash sequence in auto. keep monitoring.

please correct my mistake

thanks,

binbin

Coarse filter problem report.

We have 2 coarse filters (filter 1 and filter 2). Each filter contains a basket. They are used in the water injection system for filtering particles of more than 75u.
The normal operational mode is one filter on duty and one on standby.

day 1: As normal operation, we opened filter 2 for inspection and found the basket filter had burst. This was replaced with a new basket.
Filter No2 was then put on line and worked satisfactorily. No1 filter then cleaned.
day 2: No1 filter again put on line as No2 filter was indicating an high DP.
day 3: Filter 2 put online, and isolated filter No1, due to basket burst after backwash sequence failed to cause high DP across filter.
day 4: No1 again put online, but this time without a basket.
Isolated filter 2 due to an high DP again. Even manually started backwash motor for running continuously.
day 5: We decided to insert yet another new basket for filter No2, and took out the existing filter for chemical cleaning.

After this step, filter No2 is online with another new basket, and can handle normal water flow through filter, and backwash sequence in auto mode as normal, but DP across filter causing an high alarm within 4 minutes of backwash being stopped.

day 6: We decided to install a new basket, which had been chemically cleaned, into filter No1. Then we put both filters online in parallel for sharing water flow through both flters.
With both filters online, DP indicates an in-range figure, with backwash sequence in auto.

We have continued to monitor.

thank you very much for your correction