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1 INTRODUCTION

The maritime industry has many characteristics that

distinguish it from other industries in the world. It has

mobile assets that often operate on unpredictable

routes, travel far around the world and dock in some

remote ports… All these characteristics make the

management activities in the maritime industry more

complicated and complex than in the land-based

industry. Accordingly, the organization of good

maintenance in the maritime industry is also more

complex than in the land-based industry. By definition,

good maintenance is the only means of improving

reliability “during the stage of usage of the system” [1].

Successful maintenance requires that a sufficient

quantity of spare parts is made available prior to

maintenance, or in other words, spare parts and

maintenance are “closely related logistics activities where

maintenance generates the need for spare parts” [2,3].

Similar to the land-based industry, the cost of

purchasing and storing spare parts is an important

item in a company's budget in the maritime industry.

Therefore, monitoring and managing spare parts is of

paramount importance in any serious business,

including the maritime sector. Nowadays, the

monitoring, management and supervision of spare

parts is a detailed organized process where

Computerized Maintenance Management Systems

(CMMS) [4,5] are used for the organization. These

systems allow constant monitoring of all segments of

the spare parts system, provided that personnel

regularly update quantities and enter all necessary

data.

Numerous CMMS are in use today, some of which

have been developed specifically for the maritime

A Comparative Analysis of Spare Parts Management

in Land-Based and Maritime CMMS

A. Mišura, T. Stanivuk, I. Pavlović & L. Stazić

University of Split, Split, Croatia

ABSTRACT: The organization of maintenance means the organization of the workforce (with tools and

knowledge) required for maintenance and the provision of the consumables and spare parts required for this

maintenance. Therefore, the organization of maintenance is a complex process where it is necessary to use modern

tools such as Computerized Maintenance Management Systems to make it as simple and successful as possible.

Many industries have developed special systems that meet their specific requirements and needs. The maritime

industry has its own peculiarities and differs in its rules and regulations from the land-based industry, and it is

to be expected that the Computerized Maintenance Management Systems intended for it will differ from the

systems used in the land-based industry. In order to determine the differences between the design of the system

in the maritime and land-based industries, four different systems were analyzed in this paper, two for the

maritime industry and two for the land-based industry. As no significant conceptual differences were found

between the systems, the actual use of the system was analyzed to determine what should be done in the maritime

industry within Computerized Maintenance Management Systems to comply with rules and regulations.

http://www.transnav.eu

the International Journal

on Marine Navigation

and Safety of Sea Transportation

Volume 19

Number 2

June 2025

DOI: 10.12716/1001.19.02.22

524

industry. Previous research in the field of inventory

policies [6] has shown that the characteristics of

inventory policies in the maritime industry differ from

normal land-based inventory policies and that current

rules and regulations [7-10] in the maritime industry

support this distinction. Following this logic, it is to be

expected that the spare parts management in the

CMMS for the maritime industry is different from the

setup for the land-based industry, i.e. that the system

logic and configuration is different. To verify this

assertion, four programs are analyzed, two programs

for the land-based industry and two for the maritime

industry.

The first program created as a universal program is

SAP ERP (Enterprise Resource Planning), one of the

best known programs for resource planning in the

land-based industry. The description on the official

website defines ERP as an integrated system created to

efficiently manage the financial side of operations,

human resources, spare parts, services, purchasing,

maintenance and all other processes related to the

management of the company. The second program

analyzed is also a general purpose ERP program used

in the industry: IBM Maximo Asset Management. Two

programs developed for the maritime industry that are

compared to SAP and MAXIMO are AMOS BS and

BAASnet. Both programs are competitive and widely

used in the maritime market, and their features are

common in the industry.

In the land-based industry, it is common practice to

constantly monitor the stock of spare parts and order

parts when needed. The time of ordering is not taken

into account and the quantity ordered is often always

the same. In the land-based industry, as mentioned

above, a variable period, variable quantity or variable

period, fixed quantity ordering policy is applied. On

board a ship (in the maritime industry) the conditions

for ordering are different. The ship sails all over the

world and it is not possible to guarantee the delivery of

spare parts everywhere. In addition, the long distance

over which the parts are delivered requires precise

delivery planning in order to reduce costs. For these

reasons, the fixed period and variable quantity

ordering policy is the most commonly used policy for

ships in maritime trade [6].

Therefore, the first two programs analyzed are

expected to be set up for the variable period ordering

policy with variable order quantity or the variable

period ordering policy with fixed order quantity, while

the fixed period ordering policy with variable order

quantity is expected in the maritime industry.

Since the first part of the research presented in

Chapter 2 did not produce the expected results, the

second part of the research is carried out, i.e. an

analysis of the use of these systems is performed,

focusing on the fact that rules and regulations in force

in the maritime industry must be followed [7-10]. This

analysis is presented in Chapter 3. The use of the two

CMMS developed for the land-based industry is

analysed first, then the same approach is used for

CMMS in the maritime industry. In the Discussion, the

identified facts are compared and a Conclusion follows

on how the systems are built and what the crew in the

maritime industry does (have to do) to fulfil the

requirements.

2 PROGRAMS SETUP

As mentioned earlier, previous research in the

maritime industry [6] found that the fixed period

(period R is fixed, in the analyzed databases it is set to

3-12 times per year) and variable quantity ordering

policy is the most commonly applied policy for vessels

in the maritime industry. It was also found that various

maritime rules and regulations [7-10] prescribe the use

of safety-critical spare parts, i.e. the quantity that

should always be on the ship to ensure that the ship

arrives safely at the nearest port in case of an

unforeseen event (Figure 1.).

Figure 1. Spare parts policy for the maritime industry [6]

This quantity may not be used in any other situation

and is essentially a zero quantity when considering the

normal process of ordering spare parts. It is therefore

assumed that this is reflected in the appearance and use

of the CMMS, i.e. that the systems at sea are different

from those on land.

2.1 System 1, SAP ERP setup

SAP ERP is enterprise resource planning software

developed by SAP SE [11]. It is the largest company on

the ERP market (in the land-based industry) with the

largest number of customers (according to the

available information, there are more than 433,000

customers using SAP ERP) and it is not limited to the

ERP segment, there are many customers using other

modules, for example accounting modules. As the

market leader, the solutions applied in the program are

copied in many other programs. SAP is also widely

used in the maritime industry, but is limited to the

accounting modules, the ERP module is not used in the

maritime sector to the knowledge of the authors of this

paper (or at least we have not come across it).

The structure of SAP ERP spare parts is shown in

Figure 2.

Figure 2. SAP ERP main spare parts page [11]

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Although the program was originally created for

operation in English, it can be seen that in this case the

program has been adapted to the local language.

It shows the main page of the spare parts with the

spare part number and the unit of measurement

(piece). There are further details and a detailed

description of the stock location. On the same page

there is a log with the details of the quantities.

Figure 3. shows spare parts page with quantity

details.

Figure 3. SAP ERP quantity details [11]

The quantities can be easily adjusted by adding the

number in the field. Maximum order quantity is

marked with number 1, maximal spare parts stock is

marked with number 2 while minimal order quantity

is marked with number 3. Reorder quantity or reorder

level is marked with number 4 and order lead time is

indicated with 6. The field marked with 5 is order cycle

duration, a field which determines duration of the

cycle.

This system structure enables (and requires)

constant monitoring of the spare parts quantity and

updating of the quantities consumed and received.

When the quantity drops to the reorder level, there are

no protective measures, i.e. operation continues

without the operator recognizing this condition if no

additional protective measures are in operation (which

is a normal addition to the system). This inventory

policy can be described as a constant review, fixed

order quantity inventory policy where the order period

can be adjusted (labeled 5), but this measure requires

extensive additional programming and a tremendous

amount of effort to implement this practice. According

to the information gathered, there is no example of this

practice in companies in the area. Without this

customization and expansion, the setup is a constant

review inventory policy with variable order quantities.

2.2 System 2, MAXIMO setup

Maximo is asset management software created for

land-based industry, and initially released in 1985. In

2006, the program is purchased by IBM, and it was

named IBM Maximo Asset Management. Today, there

are more than 3,923 companies that use IBM Maximo

[12] as their main help in organizing their operations.

Maximo spare parts setup is created as a list of

inventory items (red arrow on Figure 4.) with the

description of the stored item and the description of the

storage (encircled in red). On other subpages there are

more details like where the spare part is used, units of

measure, etc.

Figure 4. Maximo main spare parts page [12]

The part on the screen is Body Flange gasket, girth

flange which can be found (if stored) in the Main store,

Stbd Sponson. On the next subpage, which is visible on

Figure 5., details about spare parts quantities are

shown. This item has a reorder point, safety stock and

Economic Order Quantity (EOC) adjusted accordingly,

while maximum is left to 0.

Figure 5. Maximo quantity details [12]

The system setting shown requires constant

monitoring of the spare parts quantity and constant

updating of the quantities consumed and received. If

the quantity drops to the reorder level, there are no

safety precautions, i.e. the process continues to run

without a corresponding order, without this condition

being recognized by the operator.

It can be seen that this setup does not have order

cycle time, which was present in SAP ERP. This

inventory policy can be described as a permanent

review inventory policy with a fixed order quantity

where the order period is not defined. The main

problem of this system is the control of spare parts at

the reorder point (or below), which depends only on

appropriate actions by the operator.

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2.3 System 3, AMOS BS setup

AMOS BS [13] is one of the oldest programs intended

for maintenance planning and management of spare

parts used in the maritime industry. It has been on the

market for more than 30 years and many other

programs are created following this design.

Despite being an old program, its features are still

actual and it is still used by many shipping companies.

AMOS BS spare parts setup (for a randomly chosen

equipment and part) is shown at the Figure 6.

Figure 6. AMOS BS quantity details [13]

The description of the spare part is given on the

general page, where the name of the article is given,

together with the details about the article in the field

Maker’ ref. and details about storage location. At the

same page there is a setup of minimum, maximum,

reorder quantities and reorder level. The part on the

screen is 1st stage valve for an emergency compressor

L50, which can be found (if stored) in the Engine Store

in the Box 11. It has a set maximum and minimum

stock quantity, as well as the quantity when these parts

should be ordered and the quantity that should be

ordered. It also shows that at this moment, there is one

spare valve on board and that this spare part should be

ordered.

The system adjustment as shown requires

constantly monitoring of spare parts quantity and

constant update of the consumed and received

quantities. When the quantity drops to Reorder Level

the order should be created, but in this program, that

function requires some additional programming and

more efforts.

This inventory policy, as described above is

permanent review inventory policy with fixed order

quantity, with variable period order policy. Fixed

order policy can be obtained by accumulating many

spares at the reorder level and ordering them at the

predetermined interval, in that case stock minimum

and reorder level should be adjusted accordingly to

prevent out of stock situations which are not

recommended (allowed) in the maritime industry.

2.4 System 4, BASSNET setup

BASS Company [14] is founded in 1997 in Norway.

Their program BASSnet quickly become one of the

leading programs for maintenance planning and

management of spare parts used in the maritime

industry. Today, its new variants are among top global

programs for ERP in maritime industry as well as for

rigs and floating productions, storage and offloading

vessels (FPSOs), as well as offshore units.

BASSnet spare parts setup (for a randomly chosen

equipment and part) is shown at the Figure 7. The

analysed spare part is Handhole gasket as given in the

field material name.

Figure 7. BASSnet main spare parts page [14]

The description of the spare part is given on the

central part together with some main information.

Manufacturers details are addressed in subpage details

(marked with number 1 and encircled in red). Location

setup (storage of this item) is visible on the subpage

Locations (marked with number 2 and encircled in

red), A setup of minimum, maximum, working,

reorder quantities and levels is presented on Figure 8.

and it is organized on another subpage (encircled blue

and marked with number 3 on Figure 7.)

The system adjustment as shown requires

constantly monitoring of spare parts quantity and

constant update of the consumed and received

quantities, same as all other analysed programs. When

the quantity drops to Reorder Level there is a feature

in the system which allows appropriate action, but

which require additional adjustments and efforts and

which analysed company did not use.

Figure 8. BASSnet quantity details [14]

Same as with AMOS, this inventory policy is

permanent review inventory policy with fixed order

quantity and variable period order policy. Fixed order

policy can be obtained by accumulating many spares at

the reorder level and ordering them at the

predetermined interval, all of this has to be performed

by operators without additional support from

program.

2.5 Setup comparison

After examining four different CMMS, two of which

are intended for use on land and two for the maritime

industry, the results are not as expected. All the

examples presented have exactly the same spare part

design, i.e. despite their design, there is no

fundamental difference between their spare part

solutions. All CMMS have a setup of minimum,

maximum, working and reorder points, albeit in

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slightly different forms. None of the programs

examined has a safety-critical spare parts inventory.

All programs require (and support) constant

monitoring of spare parts quantities and constant

updating of quantities used and received. They also

support the automatic ordering process, provided that

minimum and reorder quantities are defined.

In all the programs studied, the system is designed

to allow a permanent review inventory policy with a

fixed order quantity and variable period ordering

policy. The fixed period ordering policy is not an

option in any of the systems examined; only SAP

supports this, and only after extensive program setup.

These results raise an important question. If all of

the programs studied are nearly identical and do not

support the inventory policy prevalent in the maritime

industry, how did the users of the programs studied

solve this problem?

3 USE OF THE CMMS IN MARITIME INDUSTRY

The research of spare parts ordering policies in the

maritime industry [6] found that the predominant

method is the fixed period, variable quantity ordering

policy. In that research it was found that the fixed

period is usually determined by the company and

varies between 3 and 4 months (in some cases even 2

months). The variable quantity is based on future

maintenance needs (planned maintenance) and the

quantity on board, and in all cases studied, the

applicable rules and regulations [7-10] for safety-

critical spare parts were implemented.

Comparing this fact with the conclusion from the

first part of this research that all the programmes

studied are designed to allow a permanent review

inventory policy with a fixed order quantity and a

variable period ordering policy, and that the fixed

period ordering policy is not an option in any of the

systems studied, a question arises. If the system is not

configured to perform the intended fixed period,

variable quantity ordering policy and crews

(companies) actually use it, how do they do it? This

second part of the research focuses on answering this

question.

3.1 System 3, AMOS BS usage

The critical spare parts in the company using AMOS BS

are properly labelled in the system. Although the

system offers several options for labelling criticality

(Figure 9), the company studied uses only one, namely

"Critical".

Figure 9. AMOS BS Criticality setup [13]

The company under investigation stated that all

required Critical and Safety-critical spare parts are

properly labelled and that the minimum quantities of

these spare parts are entered into the system. The

minimum corresponds to the sum of the Safety and

Safety-critical spare parts. The actual labelling and

quantities entered are verified by comparison with the

Lloyds Register [8] list for Fuel injection pumps and

Fuel injection piping (see Figure 10).

Figure 10. Part of Lloyds Register list [8]

The number of ME fuel injection pumps and fuel

injection piping in stock is shown in Figures 11 and 12.

Figure 11. ME Fuel injection pump in the CMMS [8]

Figure 11 provides an insight into the ME injection

pump complete (as a spare part). The pump is properly

labeled as critical, a minimum stock level is set, and

there is more than the minimum quantity on board.

Figure 12. ME Fuel piping in the CMMS [8]

Figure 12 shows an insight into the ME injection

piping, from which it can be seen that they are properly

labeled as critical, a minimum stock level has been set

and the minimum quantity is available on board. A

further check showed that all safety critical items have

been entered into the database, with the minimum

quantity adjusted to match the Lloyds list [8].

Neither a reorder point nor a reorder quantity has

been set for any of the items examined. The company

believes that these quantities are not required and that

the crew must check all quantities again before

ordering. In this case, spare parts planning is based

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solely on the experience of the crew, the spare parts are

not linked to the corresponding work orders, i.e. it is

possible to call up all the work planned for the desired

period in the system, but the spare parts (to be)

consumed are not linked to any work.

From this insight it becomes clear that the ordering

policy with fixed periods and variable quantities is

made possible by human labour and extensive

planning outside the CMMS. The system itself is not

adapted to its full potential and crew (company) does

not take full advantage of its benefits.

3.2 System 4, BAASnet usage

Similar to the company using AMOS BS, the critical

spare parts in this system are properly set up (as

indicated by an arrow in Figure 13).

Figure 13. BASSnet order setup [14]

As for the safety-critical spare parts, in this

examined case, as in the previous example, there is no

difference between the labelling of critical and safety-

critical spare parts, all are labelled as critical (Figure

14).

Figure 14. BASSnet critical spares tick [14]

The safety-critical spare parts listed in the Lloyds

quantities entered as Minimum stock levels. The

verification showed that the Minimum stock levels in

the CMMS are greater than the Lloyds Register list,

which confirms the company's claim that the minimum

stock level in the CMMS is the sum of safety critical and

safety stock.

Comparing the quantity of safety critical spares in

the Lloyds Register list [8] with the Minimum stock

level, it is clear that the Minimum stock level is greater

than the quantity required by the Lloyds Register [8].

From this, second insight, it also becomes clear that

the ordering policy with fixed periods and variable

quantities is made possible by human labour and

extensive planning outside the CMMS. The system also

is not adapted to its full potential and does not provide

full advantage of its benefits.

3.3 CMMS systems use comparison

Two cases analyzed from the maritime industry show

exactly the same results. Both companies comply with

all the requirements laid down in the rules and

regulations [7-10]. In both companies, the critical items

are clearly labeled with the minimum quantity is

adjusted as needed. The same logic is applied in both

companies: Safety spares and Safety-critical spares are

both labeled as critical.

In regards ordering policy, both companies are

using fixed periods and variable quantities ordering

policies. Both companies have not set a reorder point

or reorder quantity, but rely on the crew to check

everything necessary when ordering. Maintenance

planning is well established in both cases, but in both

cases the spare parts required for maintenance are not

linked to the planned work. Therefore, the spare parts

planning capability is neglected in both examples,

resulting in a much more difficult ordering process.

The spare parts planning functionality requires an

additional modification of the CMMS data, i.e.

checking each individual work order in the system and

linking the corresponding spare parts. This additional

modification cannot be done by an ordinary data entry

person, but requires a person who is well versed with

the CMMS and engineering technology, preferably a

senior Marine Engineer. This measure is therefore very

time consuming and costs more than a complete

CMMS with a standard database. In view of these facts,

it therefore makes sense to dispense with spare parts

planning.

4 FIXED PERIOD, VARIABLE QUANTITY

ORDERING IN CMMS

Of the four systems analyzed, only SAP supports the

fixed period ordering policy. To gain insight into the

main reason why this ordering method is not set in

CMMS, inquiries were sent to the companies that own

the above programs and do not have this option

available. Two out of three companies responded to the

inquiry that such a request has never been made and

the programs can be changed relatively easily and

quickly if needed.

When asked whether it was possible to add an

additional field to the program with the designation

"safety-critical spare part", all companies replied that

this was a simple and easy procedure and could be

done in a very short time, both for new programs and

for those already in use.

The other issue is the price of implementing the

ordering policy with a fixed period and a variable

quantity. The process must start with entering the

critical spare parts quantity into the CMMS. Then the

safety critical spares, the minimum stock level and the

reorder point must be added. This part of the database

change requires a lot of work, but no technical

knowledge, just adherence to company practises and

policies set out in the Safety Management System

(SMS).

The last item to be entered into the CMMS is the

determination of the required quantity of spare parts to

be used for each individual work order. This part of the

process requires a highly qualified person and a lot of

time, considering that there are more than 30,000 spare

parts in the mentioned databases that need to be linked

to more than 500 work orders. An additional problem

with all of this is the possibility of human error (about

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3-4% of the data entered [15]), which ultimately makes

the end result questionable (who wants to order

unnecessary or incorrect parts).

The latest information about the introduction of a

fixed period, variable quantity ordering policy came

after a query about the cost of this facility. There are

many manufacturers of maritime CMMS databases,

and the authors contacted several to find out how

much it would cost to create this facility. Only one

company responded that they had the ability and time

to participate in the project. Although they did not give

an exact figure, they estimated that two technicians

would be needed for a period of three to four months.

The cost of this can be estimated knowing that a CMMS

database can be completed within two weeks and costs

approximately $8,000 - $10,000.

5 CONCLUSION

It has already been mentioned that at the beginning of

this research it was assumed that spare parts

management in the CMMS for the maritime industry is

different from the setup for the land-based industry,

i.e. that the system logic and configuration is different.

While this assumption was not confirmed during

the research, the results confirmed a very different fact.

Two programs intended for use on land were

compared with two programs intended for maritime

use and the analysis showed that their basic concept is

largely identical. This conclusion is not (and cannot be)

affected by the minor differences.

Having established that the system settings are the

same, an analysis of the ordering method was carried

out, as the ordering methods in the shipping industry

differ from the CMMS settings. Namely, the two

companies studied from the maritime industry use a

fixed period, variable quantity ordering policy,

although the system is set to a constant monitoring,

variable quantity ordering policy.

It was found that the fixed period and variable

quantity ordering policy is made possible by human

labor and extensive planning outside the CMMS,

where the spare parts planning function is not possible

due to the high cost.

In conclusion, there are no differences in the

ordering policy between land and sea CMMS. The only

difference is the personnel and their ordering practices.

Parallel studies have shown that it is possible to

introduce an automated ordering policy with a fixed

period and variable quantity. This comes at a

significant cost, which is not welcome in today's

competitive maritime industry. Another problem is the

possibility of human error, which would result in the

wrong parts being ordered. Both problems are difficult

to solve with existing CMMS. Future systems must

be able to learn (to order parts that were consumed

during the last maintenance), but also to make

independent conclusions and predictions.

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