Work in sewers is nothing for the weak at heart. The people and equipment involved must be able to withstand rough going. Yet nonetheless, those doing the work need to rely on fine intuition as well. Willi Schwalm knows this craft from way back. Experience has shown that hardware used in sewers, to be effective and reliable, must be of the highest quality. Anything else is of little or no use. Willi Schwalm has built lateral connection packers in his machine shop for many years. For those not familiar with these machines, they are special systems used to install short liners and hat liners in underground sewer lines. The process is similar to stent insertion as practiced in vascular surgery. Willi Schwalm has a patent for his hat liner packer. And his rights to the name “Hutliner” (the original German term) as a designation for hat liner seals are also protected by law in Germany.
A hat liner packer is essentially made up of steel and rubber. That sounds simple enough, but in reality it is not. It must be designed, measured, cut and welded together. Nephew Bruno Schwalm is responsible for all steel working operations. Willi Schwalm takes care of all matters relating to rubber materials, assembly and quality control. Selected suppliers provide cut-to-size components made from premium materials. The craftwork done here is a cross between manual craftsmanship and an industrial joint venture. The results: top-of-the-line machines which can be sent into sewer lines between 100 and 800 mm in diameter to effect remote-controlled repair. And why the hat? To line and therefore resurface defective junctions between the main line and lateral branch lines. And there is a lot of work to be done here.
Long ago, Willi Schwalm transferred the responsibility for management of the company to his son Martin. But even to this day, Willi Schwalm makes hat liner packers in his machine shop in Schulstrasse 10 in Bad Hersfeld. No one can say for sure how many he has built to date. The number is probably somewhere around 1000. At first, no one kept count. Since then, consecutive serial numbers up to 760 have been given. One thousand machines. Not a whole lot, one might think. But a hat liner packer is not a Game Boy. Only companies in the sewer rehabilitation business own such machines. Imitations are out there. But they often are useless. In the sewer rehab industry, everyone knows the name Willi Schwalm. There is hardly a sewer rehab contractor around that is not using at least one hat liner packer from Willi Schwalm. In any event, the demand in the marketplace is such that all suppliers are kept busy. The total length of sewer lines to be serviced in Germany alone is greater than the distance from here to the moon. Sewer line rehab is an never-ending story. And down here on the Earth as well, there is a lot to be done. But not by fly-by-night artists. It’s no secret that the regulations governing quality assurance and reinstatement of sewer lines are getting stricter by the day.
A stone’s throw away, at Industriestrasse 16 in Bad Hersfeld, is where sister company Schwalm Robotic GmbH is located. This is where the packers are sold and shipped from. This is where Schwalm is still searching for new paths and better solutions in the fields of trenchless sewer rehabilitation and robotic systems. Here too, the trailblazers are at work. Schwalm at work.