Masoneilan 87/88 Standard Temperature Kits, Actuator Spare Parts (-30 to 83 °C)

Overview

The Masoneilan 87/88 standard temperature kits are the actuator spare parts kits that Baker Hughes lists with the description “Std Temp. -30 to 83°C” in its Actuator Rebuild Kits fact sheet. Five part numbers belong to the group: 720050175-999-0000 for size 6, 720050177-999-0000 for size 10, 720050179-999-0000 for size 16, 720050181-999-0000 for size 23 and 720065596-999-0000 for the long-stroke size 23L. Baker Hughes states that a rebuild kit holds the soft goods of the actuator, namely diaphragms, O-rings and wiper seals, plus safety labels, washers and similar small parts, so that a worn actuator can be brought back to as-new condition.

The size 10 and size 16 numbers of the Masoneilan 87/88 standard temperature kits already have their own pages under the format used in customer RFQs, 720050-177-999 (size 10) and 720050-179-999 (size 16). This family page adds the three missing numbers and shows all five side by side.

In Oman and the GCC, Seven Star LLC supplies the Masoneilan 87/88 standard temperature kits to refineries, gas plants, power stations and desalination sites in Oman and the GCC, and matches each kit to the serial plate of the actuator being overhauled.

Masoneilan 87/88 Standard Temperature Kits: Part Numbers

The part numbers below are copied from the Baker Hughes fact sheet, which prints them in the form 720050175-999-0000. Quote them in that form and add the actuator serial number.

Materials of the Masoneilan 87/88 Standard Temperature Kits

The 87/88 technical specification (Rev. D, 01/2026) defines the standard design range as −30°C to +83°C (−22°F to +181.4°F). In that class the stem wiper (item 11) is polyurethane, the O-rings (items 12, 13 and 85) are Buna-N, the seal washer (item 15) is steel with rubber, and the diaphragm (item 25) is Buna-N with polyester fabric. The instruction manual calls the standard elastomer “NBR [Black]”, so a black diaphragm points to this class and an orange silicone diaphragm to one of the two wider-range classes.

Baker Hughes does not publish an item-by-item bill of materials for each kit number, so Seven Star LLC confirms the exact contents with the order instead of promising a list the documents do not contain.

Size Data for the Five Standard Kits

The Masoneilan 87/88 standard temperature kits follow the actuator, so the actuator figures below decide which line applies. Values come from the 87/88 technical specification and instruction manual.

All sizes accept a maximum supply of 60 psi (4.1 bar). Torque values are nominal with a tolerance of ±10 percent, according to Table 3 of the manual.

Fitting the Masoneilan 87/88 Standard Temperature Kits

For a Model 88 (air to open) the manual, section 7.1, starts with shutting off air, isolating process pressure and placing any handwheel in neutral. The tension bolts (items 27 and 28) come off last and in several steps because the case is under spring load. A Model 87 (air to close) additionally requires the plug stem to be disconnected from the actuator stem, and with a handwheel the assembly must be disengaged first. Stem wiper, O-rings and seal washers are renewed together, coated with Dow Corning Compound III or equal, and the seated position of the plug is recalibrated afterwards (section 10).

Key Features

• Masoneilan 87/88 standard temperature kits cover five actuator sizes: 6, 10, 16, 23 and long-stroke 23L
• Design range of −30°C to +83°C for ordinary refinery, gas and power service
• Buna-N diaphragm and O-rings with a polyurethane stem wiper
• Fits both air-to-close Type 87 and air-to-open Type 88 actuators
• Supplied against the actuator serial plate with Baker Hughes documents

Industrial Applications

The 87/88 actuator family serves steam turbine systems, condensers, heat recovery steam generators, distillation, hydroprocessing and compression. In Oman that means combined-cycle power and desalination plants, the Sohar refining and petrochemical complex and gas treatment facilities, where the Masoneilan 87/88 standard temperature kits restore control valves at planned shutdowns. While the actuator is open, check the air set, positioner, mounting kit and tubing, as the fact sheet advises, and consider the Masoneilan SVI FF positioner on the same valve. Review the complete Type 87/88 actuator, or order a size-specific part such as the 010864-003-779 size 6 diaphragm.

When the Masoneilan 87/88 Standard Temperature Kits Are Not Enough

The standard class stops at 83°C. Actuators near uninsulated hot lines or on cold-climate equipment may need one of the two silicone options with a 100°C ceiling, the −40°C class or the −50°C class. Parts from different classes must not be mixed with the Masoneilan 87/88 standard temperature kits.

Compare the Masoneilan 87/88 extended temperature kits and Masoneilan 87/88 ultra-low temperature kits before ordering.

Technical Specifications

The table summarizes the data Baker Hughes publishes for the Masoneilan 87/88 standard temperature kits and the actuators they serve.

Request a Quote for Masoneilan 87/88 standard temperature kits

Send Seven Star LLC an RFQ for the Masoneilan 87/88 standard temperature kits with the actuator model, size, serial number and quantity. In Oman and the GCC, we confirm size and temperature class, check regional availability and attach the official Baker Hughes documents. Contact the instrumentation division in Muscat to begin.