For this type of pump, the barrel is put in the well to the
designed depth with tubing. And then put the plunger into the
barrel with sucker rod. Given the tubing size, the bore of the
tubing pump is larger than that of the rod pump, so the pump rate
is higher. According to seating mode, the rod pump can be divided
into three types: THC pump (Stationary Heavy Wall, Cup Seating,
Tubing pump), THM pump (Stationary Heavy Wall Mech. Seating, Tubing
Pump) and THD pump
