Quality Control


Acknowledgements : Bionic Research Institute - Chute Design Conference 1992

QUALITY control is an important element in any large mechanical engineering project.

This paper reviews the principles of quality control as they relate to the bulk materials handling environment.

Tom Phillips is the Quality Assurance Manager of the South African Breweries. He is a member of six professional Institutes and Societies, and a director of the Bionic Research Institute.



Due to the complexities involved in today's business environment there is a constant need that a clear and unambiguous understanding should exist between Client and Supplier as to the requirements of each.

From a Manufacturer's viewpoint it is no longer economically viable for him to be spending time re-working or repairing - or worse still - scrapping an item of equipment. 

Likewise from the Client's viewpoint, he wants his equipment on time and to the required quality standard.

Without a clear understanding between the parties of what each other requires and expects, it can lead to confusion, frustration and disappointment for all.

Now this understanding does not just happen and automatically fall into place by simply reading the applicable equipment specifications, the enquiry and/or purchase order documents. In fact on too many occasions both Client and Supplier have found to their cost that their respective requirements were not fully understood.

Today I shall address the need to consider the introduction of a simple I yet concise method of fulfilling the needs of all parties by producing, what is commonly termed a Quality Control Plan.

Simply put, a Quality Control Plan or QCP as it is commonly referred to is a document which clearly and systematically identifies and lists in a chronological sequence all the major events and activities which have to be performed both by Client and Supplier from the inception of a contract through to its completion and acceptance. Even simpler put it is a t checklist of activities.


QCP's are normally the responsibility of the Supplier to produce.

Formats may vary depending on the Supplier's approach and the type of work in question but it should make allowance for certain criteria to be adequately presented. The following should be included: 


The QCP is a chronological sequence of quality related activities each of which must be clear , description and unambiguous. The quality related activities should follow in the correct manufacturing sequence. Activities briefly state the operations to be performed and the type and extent of controls which require to be applied. 

The following are a list of activities which could be applicable to a contract:

The above controls are normally drawn up and agreed upon by both Client and Supplier, prior to any work being performed.

The normal criteria should always be fit-for-purpose. On the one extreme l there could be an air receiver built to a pressure vessel code and on the, other a simple piece of ducting which only requires good engineering practice.

Each activity should be referenced to the applicable specification/acceptance criteria. 


The QCP format should have provision against each activity for the inclusion of control points and signatures indicating acceptance on completion. Allowances must be made for the Supplier's responsible person, the Client representative and an independent Third Party as required.

The following control points are the most common:


After the QCP control points have been established against each activity by agreement with both Supplier and Client it only remains for the formal approval of the document to take place. 

The Supplier shall indicate his own approval of the QCP in the first instance. 

If the Client representative who had the input into the control points also has been given the authority then he will approve on behalf of the Client. 

In the event of a Third Party being involved his approval signature should also be obtained. 


The QCP becomes a living document during the manufacturing life of the item or equipment. 

Properly followed and completed by all the relevant parties it can give assurance that everything is under control and the quality activities are being performed in accordance with the agreed requirements.


Quality Control Plans ensure that a consistent level of quality control is maintained throughout the manufacturing life of an item or equipment. 

They are a means of measuring the required quality levels and ensuring that established standards are met. 

They formalize the manner in which quality is monitored and recorded for any particular activity.

At the completion of a contract they form part of the records as documentary evidence that the work has been performed to the Client's satisfaction