(Adds details on each refinery, context)
By Marianna Parraga
HOUSTON, Aug 1 (Reuters) - Venezuela's oil company PDVSA expects its refining network to work at 44 percent of capacity in August due to a lack of light crude and spare parts and planned maintenance work, according to an internal report from the state-run firm seen by Reuters on Tuesday.
PDVSA's refineries in Venezuela and the neighboring island of Curacao, which can process up to 1.64 million barrels per day (bpd) of crude, last month worked at 45 percent of capacity due to similar issues, minimizing the company's fuel exports and increasing the need for imported products.
The expected decline in August will come from lower processing rates at Puerto la Cruz, Amuay and Cardon refineries, which currently have seven out of 12 crude distillation units out of service due to lack of specific crude segregations and extended maintenance work.
Cardon's distillation unit No. 2 could restart in mid-September after planned maintenance work, according to the report.
Venezuela's oil output has consistently declined since 2012, affecting exports and availability for domestic refineries, particularly hitting the 187,000-bpd Puerto la Cruz refinery, which is expected to operate at 32 percent of capacity this month.
But in mid-August the company is also planning to restart a crude distillation unit at its 335,000-bpd Isla refinery on Curacao, partially compensating for lower processing rates at other facilities.
The Isla refinery uses PDVSA's crude as well as imported oil, mostly from the United States. Payment delays have this year affected several deliveries as most suppliers ask to be prepaid before authorizing tankers to discharge their cargoes.
Lower crude processing at its refineries would allow PDVSA to export slightly more crude in August. It plans external sales of 1.37 million bpd this month versus 1.36 million bpd in July.
But the increase will not be enough to significantly reduce the number of pending oil cargoes to pay for loans extended to PDVSA and the Venezuelan government in recent years, the document says. (Reporting by Marianna Parraga; Editing by Ernest Scheyder and Jonathan Oatis)