Stacking 5x online
The Pinhoser sawmill in Sertã is designed for the notching of packaging goods and pallet wood. The company processes the wood into pallets itself at various locations.
In the planning, notching capacity was specified at 120,000 solid cubic meters a year.
Jerusalem pine is processed - due to its special growth, it is a type of wood that is not entirely without concerns.
For the equipment, Pinhoser owner, António Fernandes, relied on German technology (see Holzkurier Heft 33, page 10-11): Linck delivered the profiling line, Kallfass, Baiersbronn-Klosterreichenbach/DE, was responsible for stacking of the main boards and side boards. In addition, machines from Holtec, Jörg-Elektronik, Liebherr, Vecoplan, and Vollmer are in use.
First the side boards
“With our sorting and stacking systems, for an eight-hour shift, and 250 work days a year we guarantee availability of 75%, explains Ernst Hauser, project manager at Kallfass. The lengths of main board and side board were defined as 2 to 3 m. In the profiling line, an average of 22 cut-offs per minute can be sawn.
Per trunk, up to four side boards are possible - depending on the diameter and cutting pattern, up to 88 boards per minute accrue.
In a separate sorting unit, the side boards are separated and pulled off - in the notch direction to the left. The controller divides boards into two Kallfass stacking systems. “The inner side boards, as a rule, these are the broader and better dimensions, go to stacker system L3-1. The dimensions of the side boards have been specified at 15 to 40 mm in thickness and 60 to 200 mm in width”, continues Hauser. The outer side boards are pulled off for stacker system L3-1a. Scrap is discharged at a third point.
Upstream from each of the two stackers, a transverse notching unit with three circular saws for end-cut and middle cut are installed. Kallfass specifies the capacities of the stacking systems; for the L3-1 at ten to twelve to layers per minute, for the L3-1 at eight to ten layers per minute.
“Pinhoser sells most of the side boards on the domestic market, the main boards are for export, for example to Spain or Africa”, reports Kallfass’s project manager for Pinhoser.
Main boards go on three lines
The main boards are split into pallet boards with the Linck multi-blade circular saw CSMK 285-A1. The boards are individually “peeled off” with a Kallfass device and transported on a chain conveyor, and straightening roller conveyor for sorting. An employee evaluates the boards and has the possibility of selecting three stations for the main boards.
“Poor quality, such as boards with two much wane edge, go via pullout rollers to a scanner for a subsequent evaluation.
Based on the stored assortment the scanner determines the best possible yield. “With a multiple crosscut saw, another one or two boards can still be generated and thus the best possible can be obtained from all goods”, assures Hauser. The boards are packetized with the L3-3 at eight to ten layers per minute. Scrap goes to a central disposal unit. The second main board stacking (L3-2) is reserved for thicker cross-sections, such as squared timber. Like the other stations, this station is equipped with a multiple crosscut saw and has the same capacity as the L3-3, at eight to ten layers per minute.
The best comes at the end
The main board sorter L3 is the highest capacity Kallfass system at Pinhoser. “With all other installed machines the boards are sawn individually with the crosscut saw”, explains Hauser. “With the L3, we guide the boards layer by layer through the machine”.
An additional particularity is integrated in this line: “To reduce the effort associated with impregnation, we have installed this step right in the transverse transport, upstream of packet formation. Thus the wood is guided through an impregnation curtain”, summarizes Hauser. With the L3, packetizing is executed in 14 to 16 layers per minute. “As opposed to the other systems, the L3 is equipped with batten magazines.
In addition, offset stacking is possible, which produces extremely stable packets.” And for the final step, the packets are strapped and provided on a roller conveyor for removal transport. Each stacking layer is configured for a maximum packet size with a cross-section of 1200 x 1200 mm, and a length of 3 m.
“The complex distribution of the boards was a challenge that we mastered to the satisfaction of the customer”, Hauser is pleased to report.