A pivot pipe for a two-cylinder thick material sludge pump is designed to
reduce the rate of wear of the sealing surfaces and flow bores of the
pivot pipe and cooperating outlets on the two pump cylinders. As the pivot
pipe oscillates from one pump cylinder to the other pump cylinder the
contacting sealing surfaces are subjected to abrasion and impact wear. The
present invention limits the rate of wear between the contacting sealing
surfaces and a portion of the flow bore by fixing monolithic wearing rings
on the upstream end of the pivot pipe and on the outlets of the two pump
cylinders. The monolithic wearing rings are made of a hard materials such
as cemented tungsten carbide.
