Low-cost scale-inhibiting horizontal pre-filter

The utility model provides a low-cost scale-inhibiting horizontal pre-filter which comprises a filter body, the filter body is of a tubular structure, one side of the filter body is provided with a water inlet, the other side of the filter body is provided with a water outlet, and a water outlet filter screen is mounted at the water outlet; a drain outlet is formed in the lower part of the filter body; in the cavity of the body, the filter screen supporting plate is arranged on the edge of one side, close to the water outlet, of the drain outlet; a filter screen clamping plate which obliquely extends downwards is connected to the upper wall of one side of the water inlet in the cavity of the body, the end part of the filter screen clamping plate is connected with a filter screen fixing groove, the filter screen fixing groove extends to the filter screen supporting plate along the inner side wall of the filter body, and a middle filter screen is mounted in the filter screen fixing groove; the filter screen sup