Reflections related to paper  machine operation

 

There used to be 6 paper machines in operation at the mill. However, the oldest No. 6 machine was not in operation while I worked at the mill. The machine was so old, that the  dryer gears were made out of wood. In other words, a machine which belonged to the 1800th rather than the 1900th century. The remaining 5 machines produced so many different paper grades that today all these grades would never  be produced in a single paper mill. The mill produced newsprint and rotoprint on two of the machines, the furnish mainly consisting of groundwood pulp. Two more machines produced many different weights of unbleached kraft grades such as light and heavy paper bag  and wrapping grades the furnish being mainly sulphate pulp. One machine was totally dedicated to tissue paper production the furnish being mainly sulfite pulp.

It took years to become a proficient paper maker. A paper maker would start in the finishing room and work his way up through back tending to wet end tending. The paper machine superintendent was an important person for very good reasons. The miracles he had to perform with his paper makers to get a paper slurry to run through the Ocean Falls machines to end up as finished paper was close to a miracle. When the paper was not coming off the dry end of the machines, the Mill Manager and other staff had to stand back and hope that the paper machine boss would manage to save the mill's profitability for the month. 

There is an abyss between  modern pulp and paper operators and the old paper makers of Ocean Falls, two entirely different species of paper makers. The modern pulp and paper operator is located in an air conditioned control room with subdued lighting where the operator is watching the distributed control system displays. In many cases, the operator can not see the machine or machines he or she is controlling. Every conceivable parameter involved in modern paper or pulp making is monitored by dozens of moisture, temperature, pressure and flow sensors and their output available to the operator by the touch of a computer key. Any out-of-range process variation measured by these sensors is gently and automatically adjusted by the control systems. The modern paper maker can call up any and all past events associated with these variations in the form of graphs or what have you. 

A paper machine or a pulp machine is built in separate sections, each section driven by separate drives. The relationship of the speed between the sections is very important and in paper making language called the draw. Today, variable frequency drives or DC drives control the speed of these various sections. The speed difference between the sections, or the draw, can be adjusted very accurately in the control room and the electrical control systems take care of the rest. 

The paper makers of Ocean Falls had none of these facilities. His control room consisted of a couple of electrical panels sitting in the middle of the floor between two paper machines. He would have a group of ordinary on/off switches, some amp meters and if lucky, a couple of temperature indicators/recorders in his panel. His only so called "modern" control device would perhaps be a magnetic or turbine type flow meter controlling the flow of stock to the headbox. The noise level between the machines was very high and in the summer time the temperature in the machine room would be close to that of a sauna. The concept of hearing protection was not invented at that time. Due to the heat, the papermakers would often work in their undershirts since the t-shirts were not invented at that time either. The paper stock would enter unpressurized headboxes and flow by gravity onto the wet end.

How the paper makers managed to get the "tail" ,as it is called from one section to the other is also hard to understand. The tail is the very first strip of paper which has to be threaded through the machines. The Ocean Falls paper makers would catch the soft, wet paper strip by hand and throw it into the next section hoping that it would stay there. Today, there are modern threading systems which automatically starts the travel of the sheet through the presses, dryers and calender stacks if paper.  When the Ocean Falls paper maker had to adjust the draw between sections, he would go and turn a hand wheel on the back of the machine; which then would move a belt on a conically shaped drive pulley. 

The quality control of the paper coming off the machine consisted of the Backtender running his hand over the paper on the pope reel to check for wrinkles and he would be tapping the reel with a stick to ensure that the reel was building up uniformly. The paper quality would later be further investigated by paper testers. However such feedback would not come back in time for instant adjustment should something not be right. Today,  many of the paper qualities are continuously monitored  and backed-up by state-of-the-art laboratory work. The above description of old versus modern paper making is not an attempt to belittle the modern operator. There is no comparison anymore. Paper and pulp produced today is produced at a speed and at a quality which would have been totally impossible to achieve on the old machines. The technical expertise of modern operators can not be compared to the old "hands-on" expert papermakers of the past.