Draught Survey 2

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A. The Basic Theories Of Archimedes Before going to legal Archimedes who has cautiously applied in the determination of the value of the charge which has been above board. Perhaps the readers still remember will sound the Archimedes Law reads as follows; "Objects in the field of embedded water, then the objects immersed in proportion to the weight/volume of water transferred". From the application of the law, the carrier obtained the great value of the charge on his boat in a way that is: Determination of the charge carrier by taking the value changes or differences in weight/volume of the ship when the end of the heatsink (the Final Displacement) reduced by the weight/volume of the ship during the early heatsink (Initial Displacement). [Charge carrier = Final Displacement – Initial Displacement]

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Transcript of Draught Survey 2

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A. The Basic Theories Of Archimedes

Before going to legal Archimedes who has cautiously applied in the determination of the value of the charge which has been above board. Perhaps the readers still remember will sound the Archimedes Law reads as follows;

"Objects in the field of embedded water, then the objects immersed in proportion to the weight/volume of water transferred".

From the application of the law, the carrier obtained the great value of the charge on his boat in a way that is:

Determination of the charge carrier by taking the value changes or differences in weight/volume of the ship when the end of the heatsink (the Final Displacement) reduced by the weight/volume of the ship during the early heatsink (Initial Displacement).

[Charge carrier = Final Displacement – Initial Displacement]

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B. Stage Of Implementation Of The Draught Survey

Based on the basic theories of Archimedes and image captions then we get distinction

the volume between the final volume of the heatsink (Final) volume early heatsink (Initial). Of such differences are known to weight loads located above the ship. Once we understand the theory of the law of archimedes, let's start the peeling problems how to Draught Survey began. The order of execution of the Draught Survey, namely;


The reading of the Drafts of the six points of the draft Board to reference the weight/displacement vessel. Location of the sixth draft of the ships are like the following image.


Measurement Of Ballast Tanks, Fresh Water Tanks, Fuel Tanks, Diesel Tank, Oil

Tank Wspólnej Oil, Measure the value of Density Measuring value of the Density of water, the liquid in the tank-tank above the ship, etc.


Data Pengecheckan The Ship, Data Correction Of Drafts, Calculations Of Ballast, The Calculation Of Fuel Oil, Diesel Oil, Calculation Of Calculation, Calculation Of Charge Wspólnej Oil.

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Of the implementation of the third order of the above, it can be noted the value of the volume/weight of the heatsink of the ship.

B.1. Draft Stages Of Reading

The Introduction Of The Draft Board

Regarding the Draft Reading (reading of the Draft) is possible for the beginner/student rate still confused about What questions making it appear that the Draft, as to what the Draft Board and how reading the Draft of the ship?

Indeed as to what the Draft Board, we think a beginner will quickly understand the type of Marking of the ship, but a Draft for the novice it is sometimes a little difficult especially in the readings of the draft of the ship, the sea conditions any more choppy or swell so it took a long time in the reading of the draft of the ship.

To answer your curiosity for beginners;

What is a ship's Draft? "DRAFT could be taken to mean that the great value of measurement in the field of water sinking, measured from the bottom of Keel to Surface area of water where ships are".

As to what the Draft Board, as long as it is envisaged in the draft of a ship hull using two versions of the draft, namely the size unit UNIT UNIT of meters and FEET INCH. As for example mark draft vessel that used both the unit below.

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(Figure 1.4)


-On (Figure 1.2), what if we read was about 6 m/6 m 32Cm 34Cm.

-On (Figure 1.3), A description of the raw size, the size of all multiples of 10 cm.

-On (Figure 1.4), what if we read is about 10 m/10 m 02Cm 03Cm.

See the picture below

Draft example with units of Feet Inch (Imperial System)

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(Figure 1.5 a)

(Figure 2.4 b)


-On (Figure 2.2), what if we read is about 03Inch/19Ft 19Ft 04Inch. After that we koversikan in units of Meters for penabelan calculate Displacement.(Depending on the Table to calculate whether using Meter or Imperial units)

-On (Figure 2.3), (Figure 1.5 a) and (Figure 2.4 b), is the standard base measure distance between numbers to reference basic reading of the draft.For lately many ships use units of meters, for easier reading and convert. So rare to meet ships with the

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size of the imperial units.

Tricks Of The Reading Of The Draft

Reading of the Draft of the ship sometimes makes us hassle when the ship was in the open sea (open Waters) by the sea/ocean waves is so great/are those of rhythm as well as the square so quickly. From the condition that sometimes even for beginners who've experienced hassles in determining how the draft of the ship. If you often face such problems, then you will more easily in the reading if you have any tricks/how to read a draft of the ship.

Then it's the authors will share tricks based on experience as well as good seamanship/habits of good sailors.

As for the tricks the reading as follows;

Ø Average Reading/Take the average Square.

By taking the average value of the reading of the highest and the lowest square, we noted the reading after that we share with the frequency of readings.

Ø Reading on Slack Condition/Reading time the square was quiet.

The readings in this way, we have to truly tungggu opportunity the slack/square is quiet when the square condition so fast changing and his rhythm quickly. Disela-sela change the square so quickly, there will be a condition of the slack/quiet. When the slack we read draft ship well.

Ø Reading with Floating Ball in the transparent Hose (Draft Indicator)/Readings using a Apungan in Hose.

The reading with the help of tools in the form of a ball that is placed in the apungan transparent hose would be better, because the placement of the hoses ditenggelam with standing position vertical parallel to the hull so filled by water and the ball will calm afloat in the apungan interval.Sample images supporting equipment draft or Draft Indicator reader Reader.

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Draft Indicator Reader

A transparent plastic tube/hose was given a hole on each end with a length of 1 m and 2 cm in diameter, are given a weight of about 1 kg, and was given an indicator buoy/apungan balls in tube, as in the picture above. With the existence of this tool on the indicator ball apungan apungan, would look up and down with a quiet, calm conditions when apungan ball is a point read drafts.

S fter metamorphosis pembacaa draft vessel, where the difficulty is reading the draft of the ship in the choppy waters of the condition and the rhythm of the waves so quick. When the difficulties we had skip and the reading of the draft of the ship we get her figure, then we move on to the next stage.

B. 2. Phase Measuring

Introduction To Gauge

At this stage, we are asked to measure/sounding and ullaging tanks-tanks located above the ship, these tanks are tanks, ballast tanks fuel tank boat boat engine lubricants, fresh water tank, ship megukur viscosity/density of each liquid in the tank and the density of water where the ship is located. You need to understand before making measurements, multiple gauges are used, namely;

1. Sounding Tape

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Used to measure the depth of the liquid that was in the tank, if the ballast tanks are tanks or tank of fresh water, then sounding tape we lumuri with Water Paste/Paste water, nor vice-versa if the tank is a tank fuel gauge/fuel then we use Gasoline Paste. Because of both the pasta will produce different colors when dipped into the liquid or different.

Dipping Tape/Ballast

Ballast/Fuel Tank Sounding

Sounding Tape

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2. Hydrometer and Water Sample Dipper

Hydrometer, this equipment to measure the level of viscosity/density of a liquid. Frequently used types of hydrometer which kind Zeal Hydrometer. While the Sample Dipper used to take liquid to be measured, then we place on liquid gelas a benchmark or a tube container, then we insert the Hydrometer to measure the viscosity of liquids.

The purpose of the use of hydrometer which is to know the weight of the liquid in the tank for the liquid volume of multiplication.

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Of the overall results of sounding or ullaging tank, then we convert the result sounding/ullaging with menabelkan to find out the volume of the liquid in the tank. After we get the volume of the liquid in the tank then the next step is to convert the volume with the formula above, we get the weight control liquid in tanks.

We think stage measuring up enough here, the beginner will understand this stage by reading the manual/manual calculation of loading tanks, ballast and fuel tanks, freshwater tanks.

B.3. Phase Calculation

Preparation Of Calculations

After you pass the stage of Reading and Measuring Phase, then you entered a stage of Calculation/Computation, where this stage you are required to understand, attention and precision in a deployment of observation results/pengechekan into the formula/calculation format drauht survey.

When you are finished implementing the previous stages, then have the data;

1) Draft ship.

2) Data Density.

3) Data Results Soundingan Ballast Tanks, fuel, fresh water, etc.

(Data Observations/Check with Propagator I/staff/crew of the ship).

With the three aforementioned data results, then we entered the stage of the calculation. Based on the above data, we can begin the preparatory calculations namely;

a)-Penge checkan Data/documents on board, include;-Ship Particular.-Ship Loading/Discharging Manual Booklet.-Hydrostatic Hydrostatic Table/Curve.-Displacement Table.Tank Sounding Table (Tank-tank Fuel, Ballast etc.).-Capacity Plan & Stowage PlanLoadline-Document/Certificate-Records of Ship Constant.-Light Ship/Empty Weight Early Ship when first created. - Measure The Length Of LBP (Lenght Between Proton)

b)-Penge checkan Data Corrections Draft Board.-The distance between the front with Marking Marking Draft Draft back. (LBM)

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-The distance between the front with Proton Marking Draft forward. (LF)-The distance between the center of the Metacenter Marking Draft/Midship. (LM)-The distance between the rear with Proton Drfat Marking back. (LA)Usually accompanied by image captions, like the example below.

(Figure 3.1)

Reading of the draft of the ship which was not true because we get the layout of draft mark is not right on the perpendiculer or tipping center, then it needs to be moved to the appropriate increase/decrease the value of the correction.

After the data obtained and total ship ballast, the total fuel, as well as the total freshwater is known, then we could be entering a phase of a boatload of calculations. Below is the form less lebihnya alike from all the surveyors in the execution sequence of calculation of Draught Survey.

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(Figure 3.2)

Description of processing in the Form of Calculation:

Stages 1, 2 & 3-For the Mean Draft (letter a, d & g) Mean Fwd/Mid/Mean of Mean Aft. Draft = Draft Port side + Draft Starboard side

2- Draft Correction (letters b, e & h)

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Formula To Calculate Draft Correction = Distance Draft Mark from Proton x Apparent Trim

Distance between Draft Mark (LBM)

or = Mark the middle of distance Draft Tipping Centre x App Trim Distance between Draft Mark (LBM) If

a. Trim by the stern (Rear Trim Ships), if layout Draft Mark located in front of the Centre then Proton/Tipping His is a Plus value (Corretion+).

b. Trim by ahead (Ship Trim front), if the layout of the Draft Mark located in front of the Centre then Proton/Tipping Value Correction is Minus (-).

Both of the above statutes will be reversed when the layout of the Draft Mark behind Proton/tipping centre. If you are still confused or have not understood the Draft Statutes Correction above, you can try to understand through the picture below.

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(Figure 3.2)

From the Pictures above and below we can conclude that the Draft Mark we read we need to scroll right to the position of ship's Metacentre or Proton

(Figure 3.3)

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(Figure 3.4)

(Figure 3.5)

- For True Draught (letter c, f and i), once you get a great value for a draft correction, then you can simply apply the draft of such great value by adding a correction/subtracting the mean draft.

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True ... ... Draught = Mean Draught +/-Draught Correction

Once you understand the basic Figure 3.2 as a reference draft correction. Then you can enter the next stage.

Stage no. 4

From the reading of the draft as well as search to search the whole correction, the draft actually on average. With another term True Draft or Quarter Mean Draft, with the formula calculation as follows;

Quarter Mean Draft = T Forward Draft + (6 x T Mid Draft) + T Aft. Draft


Stage no. 5Displacement Correspondent means how the value of displacement based on Quarter Mean Draft results reading of draft survey. Displacement values obtained from pentabelan at the corespondent table Hydrostatic Table/Displacement Table reference Quarter Mean Draft, in pentabelan is often done by means of interpolation for precision Displacement values for the conditions corresponding Quarter Mean Draft.An example of how to Interpolate in the Pentabelan:

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(Figure 3.6)

Stage no. 6A and 6B

At this stage (Trim Correction) we are required to better understand some of the terms used in the ship's displacement correction due to the influence of any trim which occurs above ships at the time. Before entering the deeper on this section, the author will explain some of the terms used in the correction of trim hereunder;

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Stage no. 7

At this stage, once we get a Value Trim Correction. Then to get the Displacement that have been rectified by Trim Correction, namely with the sbb formula;

Displ after Corr by Trim = Displ Corespondent +/-Total Trim Correction

Stage no. 8

List Correction/Correction is applied if the slope at the time of draught survey ship condition not erect/up right where there is a slope which affects the occurrence of the difference between the draft and draft middle Center right left the ship.

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With the tilt of the ship, you need to understand to understand why there is a Slope Correction. If you look at the layer is yellow, triangular case we are looking for great value to replace the position of the layer color is blue (the layer that does not sink). When the big Yellow layer we've got to replace the Blue layer, then we can add to the Displacement that had been rectified by the trim.

Formulae List Correction:

List Correction = 6 (D2-D1) x (TPC2-TPC1)

D12 = Draft midshipTPC12 = at the time of the draft TPC D12

(List Correction, Tonnase its value is always positive)Stage no. 9

After getting a great value for the slope correction/list correction, then you can simply add the displacement corrected by trim corrections.

Stage no. 10 and 11

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At this stage to know the case to ship at a rate of correction of thickness or weight of water where boats are fields. To find out the level of thickness of the waters surrounding the ship, then held the taking of water to measure the level of kekentalanya. Area or position where the taking of water i.e. to 6 point (front right, front left, Center right, middle left, rear right, rear left) when the ship anchored off/not sandar didermaga, when sandar didermaga then we grab the side of the sea/the waters only. The taking of sample water better is as deep as 50% of the ship's draft.

We use a type of Hydrometer Zeal has large scale to facilitate the reading, hydrometer has the units of Kg/ltr. To find Great Value using Density Correction sbb formulation;

Corretion by Density = (MD-SD) x Displacement SD

MD = value of Density in the waters of the observation (around the ship)SD = Ship/Ship based on Density Density as the standard measure of HydrostaticWhen the ship was built by Shipbuilder ... ...These standards include 1.025

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Displacement = Displacement vessel that has corrected the slope. The value of the correction is always worth "negative (-)"Stage no. 12, 13 and 14By getting a Displacement that have been rectified by the correction of density, then we stay a few steps shorter stages to get the Net Displacement of the ship. We get the value of the Net Displacement is with sbb formulation;

The Net Displacement = Displacemant Corr by Density-Deduct Weight

Weight is the weight of Data reduction to Deduct from heavy weight of the ship itself and the Constant reduction of the weight of the boat, so this is a heavy Ballast Water, Fresh Water, Fuel Oil, Diesel Oil, Spare Oil, or Other Club (meaning the extra weight to another at the time/date survey).

To get the value of the Net Displacement during the Initial and Final, then get the value of a charge which has been included by way of a dismantled or sbb;

Cargo/Cargo on Board = Net Final moments-Net Displ Displ when Initial


Penentuan Muatan diatas kapal dengan mengambil nilai perubahan atau perbedaan berat/ volume benaman kapal saat akhir (Final Displacement) dikurangi dengan berat/ volume benaman kapal saat awal (Initial Displacement).

MENGENAL PELAKSANAAN DRAUGHT SURVEY : Pada saat Loading Cargo Batubara , Kita mengenal istilah Draught Survey , Dimana tahap ini adalah tahap perhitungan Cargo yang berada diatas Barge ataupun diatas Vessel . Pelaksanaan Draught Survey terbagi dalam beberapa Tahap Penting Yaitu :

Tahap I :Mempelajari dokument kapal yang dipakai dalam perhitungan draught survey dan mencari informasi kondisi kapal terkini.

Tahap II :Pembacaan draught kapal di lambung kiri dan kanan bagian depan (forward), tengah (midship), belakang (after part)

Tahap III:Melakukan pengukuran cairan-cairan yang ada diatas kapal (fresh water, Ballast water, Fuel oil, diesel oil, Lub. oil, Hydrolic oil, other.

Tahap IV :Mengukur density air perairan dan ballastDensity bahan bakar berdasarkan informasi dari tanda pengisian terakhir

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Tahap V :Perhitungan draught surveyBuku-buku dokumentasi yang diperlukan dalam perhitungan (Bibliography book, atau hydrostatic table, sounding table/tank capacity curve)

Syarat Ideal pelaksanaan Draught survey :* Kapal tidak kandas/dapat mengapung bebas* Tali pengikat tidak terlalu kencang, kapal dapat bebas terapung* kapal tidak miring lebih dari 2derajat* tanda draught kapal dapat terbaca jelaz* pipa sounding/level gauge dapat terbaca jelaz* tinggi ombak tidak lebih 0,5 m* trim kapal tidak melebihi batas koreksi trim dalam table tanki* Table dalam kondisi up to date* Alat ukur dalam kondisi baik dan terkalibrasi* tidak ada pergerakan cairan dan alat bongkar pada saat survey

Pada waktu pelaksanaan draft survey hubungi Chief Officer agar selama operasi draft survey, kapal tidak mengerjakan :               - pengisian atau pembuangan atau pemindahan dari tanki ke tanki air ballast.               - pengisian atau pemindahan bahan bakar dari tanki ke tanki               - memasukkan atau mengeluarkan (swinging) batang pemuat/kran.               - dan lain-lain.

Koreksi-koreksi yang mesti diperhatikan dalam perhitungan :

# Draft Corrections

Draft marks (marka draft) pada lambung kapal seharusnya diterakan pada garis perpendi-kular, yaitu pada forward perpendicular, mid-perpendicular dan after perpendicular. Karena pada kenyataan dilapangan draft mark tidak terletak pada perpendiculars maka perlu dilakukan koreksi draft.

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Koreksi untuk draft depan disebut stem correction, sedangkan koreksi untuk draft belakang disebut stern correction dan pada midship disebut Mid correction.

  Rumus : stem corr = Trim obs x df Lbmstern corr = Trim obs x da Lbmmid corr = Trim obs x dm LbmDimana :

Trim observe : selisih draft mean Forward dan draft mean afterdf : Jarak antara draft mark forward/depan dengan perpendicular depan (FP)da : Jarak antara draft mark after/belakang dengan perpendicular belakang(AP)dm : Jarak antara draft mark tengah dengan midshipLbm : Lbp - (df + da)

Trim and density correction

Perlu diketahui bahwa Hydrostatic Table dll.nya dibuat dengan kondisi :1. kapal dalam keadaan rata-rata air (even keel) - kapal tidak mengalami trim.2. kapal terapung di air dengan Berat Jenis = 1,025 (air laut).

Jika kapal mengalami trim dan terapung di air dengan berat jenis tidak sama dengan 1,025, maka displacement tersebut harus dikoreksi dengan :- density correction- trim corrections.

Displacement yang didapat dari tabel disebut scaled displacement, sedang displacement yang sudah dikoreksi dengan berat jenis disebut measured displacement dan yang telah juga dikoreksi dengan trim kapal disebut corrected displacement.

FTC = Trim x TPC x LCF x 100 first trim correctionLBPSTC = Trim^2 x (dm/dz) x 50 second trim correctionLBPdimana :trim = trim setelah dikoreksi pada draft correctiondm/dz = selisih MTC1+0,5 dan MTC2-0,5

Density correction = density obs - 1,025 x Displacement corr for trim1,025dimana :density observe = density air laut yang telah diukur dengan hydrometer.List correction/ koreksi kemiringanMetric sistem LC = 6 (TPC1 - TPC2)m/t x (Dm1 - Dm2)mtrImperial sistem LC = 0.72 (TPI1 - TPI2) long/t x (Dm1 - Dm2)feetdimana :Dm1 : Draught tengah terbesar

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Dm2 : Draught tengah terkecilTPC1/TPI1 : adalah TPC/TPI pada draught tengah terbesarTPC2/TPI2 : adalah TPC/TPI pada draught tengah terkecil

Pengambilan Sample air untuk mengukur density di sekitar kapal :Dokumen kapal umumnya didasarkan pada berat jenis (density) air laut (= 1,025). Prakteknya kapal yang di survey terapung di air dengan density yang berbeda, misalnya density air tawar = 1,000. Karena itu air di sekitar tempat kapal terapung harus diambil samplenya (contoh) untuk mendapatkan densitynya.

Density (berat jenis) air di sekitar kapal dapat berbeda, karena :- kedalaman yang berbeda- tempat yang berbeda sepanjang kapal dari haluan ke buritan

Untuk menghindari pengambilan sample yang tidak benar :- sample hanya efektif sebelum/sesudah pembacaan draft.- sampling jangan dilakukan dekat saluran pembuang darat/kapal (cooling water/ballast water).- sample diambil pada sisi laut, karena pada sisi darat density dapat berbeda karena adanya air yang tidak bergerak/stagnant, antara kapal dan daratan.- segera setelah sample diambil density harus dihitung/dibaca.

Jumlah dan posisi pengambilan sample- untuk kapal kecil : 2 samples, pada sisi laut dekat draft tengah, pada kedalaman 1/3 dan 2/3 dari draft tengah.- untuk kapal besar : paling sedikit 3 samples, pada setiap posisi sampling, pada kedalaman 1/6, 1/2 dan 5/6 dari draft tengah.

Pengukuran density dengan Hydrometer

Deductibles weightAdalah jumlah berat yang harus dikurangkan untuk mendapatkan jumlah berat kapal kosong atau berat muatan itu sendiri.Deductible weights terdiri atas : - berat kapal kosong

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- air ballast- bahan bakar- air tawar- minyak lumas- perlengkapan, stores- konstan, dll.

Constant.Constant atau konstan adalah sejumlah berat yang timbul karena ada perbedaan antara displacement dan berat semua barang yang ada di kapal termasuk berat kapal kosong.

Constant = displacement - deductible weights.

Jadi konstan adalah berat benda di kapal yang tidak dapat diperkirakan, seperti lumpur di dalam tanki, karat dan lain lain. Dan dapat juga kesalahan terhadap suatu penafsiran berat suatu benda di kapal, termasuk juga kesalahan penerapan draft marks (pengelasan/ pengecatan) tidak pada posisi yang tepat.Berapa konstan dapat ditanyakan kepada Nakhoda atau Chief Officer, dan apakah ada konstan yang negatif ?

Negative constant

Ada beberapa sebab mengapa sebuah kapal mempunyai konsran negatif atau kecil sekali.Hal ini dapat disebabkan oleh beberapa alasan :    1. dokumen yang ada di kapal sebenarnya adalah dokumen untuk kapal yang identik (sister ships). 2. hydrostatic particulars tidak akurat.    3. ada peralatan atau bagian kapal yang sudah dipindahkan/dibuang, misalnya tweendeck, crane atau lainnya – hal yang biasa dilakukan oleh kapal kecil untuk menambah daya muat. 4. estimasi terlalu kecil terhadap draft kapal. 5. estimasi terlalu tinggi terhadap deductible liquid, terutama air ballast. 6. density tidak mewakili yang sebenarnya.

Jika didapatkan negative constant, periksalah lagi apa alasan atau penyebabnya, jika mungkin bandingkan dengan hasil survey yang terdahulu.Jika tidak ada alasan atau penyebab yang dapat diterima, maka keadaan ini harus dinyatakan dalam laporan bersama-sama dengan :          a. hasil efektif dari draft survey.          b. hasil dari loaded survey – lightweight (dari dokumen kapal) –               konstan (dari informasi Nakhoda).Nakhoda harus menanda tangani pernyataan yang berhubungan dengan konstan yang telah di informasikannya.


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Sebab terjadinya Cargo Losses/kehilangn atau kerugian cargo dapat terjadi pada saat :- Kegiatan muat/loading- Pada saat transportation-Kegiatan bongkar/ discharging

Pada saat Loading/transfer dapat menyebabkan cargo losses dikarenakan :- Tumpahan Cargo- Debu terbang (cargo halus)- Peningkatan kelembaban- Pengurangan ukuran- Kontaminasi / bercampur dengan sisa muatan sebelumnya atau tanah- Adanya sampling dan analisa- Salah sampling (berpengaruh terhadap kualitas)- Salah berat (mempengaruhi kuantitas)- pengukuran tidak akurat- keadaan cuaca yang kurang mendukung

Salah draught survey (mempengaruhi kuantitas)- Salah membaca draft- Salah perhitungan deductibles- kesalahan hitung- Absolute (salah) hidrostatik tabel- Salah sampling dari air laut

Pada kegiatan transportasi :- Peningkatan kelembaban- Cargo tumpah- Peningkatan suhu yang cepat- Berlebihan emisi metana- Kekurangan dalam pemuatan- Bercampur dengan kargo sebelumnya- Pengurangan ukuran

Pada kegiatan bongkar:- kalibrasi yang tidak akurat- kondisi cuaca- kapal/ barge tidak stabil- trim kapal/barge terlalu besar- kesalahan pada draught survey

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- sampling dan analisis

Cargo losses atau kehilangan cargo juga dapat disebabkan oleh faktor fisik :- penguapan- tumpahan atau kebocoran- menumpahkan- kejahatan/pencurian


1. Draught reading Device at rough Sea condition :Peralatan yang digunakan untuk melihat sarat kapal bila ada ombak besarUntuk melakukan survey dalam keadaan ombak besar diperlukan alat khusus yaitu :- tali polyphropelyne dia 8mm secukupnya- selang plastik warna putih dia 19mm panjang 6-8 m- selang plastik warna putih dia 12mm panjang 2 m- besi pemberat- lem plastik- gabus berwarna sebagai pengapung

Cara menggunakan alat ini :- tempatkan alat ini didekat marka sarat- usahakan bahwa selang plastik dia 19mm ditengah-tengah dari garis air- meski air dalam kondisi bergelombang, pengapung dalam selang dari alat ini akan tetap menunjukkan permukaan air dengan teliti

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2. Design Water sampling device :Alat pengambilan contoh airPerlengkapan yang dibutuhkan- Polyphropelyne- Tabung stailess steel dia 14cm dan panjang 60cm- besi pemberat 3,5 kgHindari pengambilan contoh air untuk pengukuran density di dekat keluarnya air pendingin mesin dari lambung kapal.

3. Sounding tapeSpesifikasi :- pita (tape) panjang min 25 m- bahan : stailess steel- tebal 1mm- pembagian jarak per 10 mm- berat pemberat 400gr

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4. Hydrometer dan tabung pembacaanAlat pengukur berat jenis air dalam satuan Kg/ltr, dilengkapi dengan sertifikat test laboratorium yang diakui. Dan secara teratur diperiksakan/diterakan dengan hidrometer bersertifikat, sehingga diketahui koreksinya.

5. Water finding pastePasta yang digunakan untuk mendapatkan atau mengetahui pembacaan yang teliti dari tinggi cairan didalam tanki. Pasta ini adalah bahan yang dapat berubah warna menjadi merah bila terkena cairan. Dipergunakan dengan cara dioleskan pada sounding tape untuk mendapatkan pembacaan yang teliti.

6. - Kalkulator/laptop

- senter- Binocular ; teropong untuk pembacaan skala draught- buku catatan- sarung tangan- Pakaian safety, helmet, sepatu dll