Topa supplies NPT one-piece hydraulic hose fittings for hose assembly, maintenance, distribution, and equipment manufacturing. Available options include straight, 45-degree, and 90-degree configurations in different hose and thread sizes.
Choose NPT one-piece fittings according to the connection type, hose size, thread size, fitting angle, and hose construction. Product codes should be confirmed together with technical specifications rather than selected by appearance alone.
This video introduces Topa’s NPT one-piece hydraulic fittings, including different connection types, fitting angles, and size options. These fittings are designed for reliable hose assembly and are widely used in construction, agriculture, industrial equipment, and hydraulic maintenance.
Topa can supply straight, 45-degree, and 90-degree NPT one-piece fittings in various hose and thread sizes. Send us your part number, hose size, fitting photo, drawing, or sample, and our team will help confirm the correct model.
Comparison Item | NPT | NPTF | NPSM |
Full Name | National Pipe Taper | National Pipe Taper Fuel, also called Dryseal | National Pipe Straight Mechanical |
Thread Structure | Tapered pipe thread | Dryseal tapered pipe thread | Straight mechanical pipe thread |
Primary Sealing Area | Thread interference with an appropriate thread sealant | Controlled interference between the thread flanks, crests, and roots | A cone seat, sealing seat, gasket, O-ring, or another confirmed mechanical sealing surface |
Thread Sealant | Normally required for a pressure-tight joint | Designed for dry sealing, but the actual assembly requirement must follow the fitting and system specification | Normally not used as the primary seal because the thread itself does not create the pressure seal |
Common Connection Form | Male or female tapered pipe connection | Male or female dryseal tapered connection | Commonly used with a female swivel nut and a matching male seat |
Tapered or Straight | Tapered | Tapered | Straight |
Main Thread Function | Provides mechanical engagement and contributes to sealing | Provides mechanical engagement and a tighter dryseal thread fit | Mainly provides clamping and connection load |
Check the hose ID, dash size, standard, reinforcement, series, and actual outside diameter.
Confirm whether the connection is Male NPT, Female NPT, Female NPSM swivel, or NPTF.
Measure the thread diameter and confirm the threads per inch, taper, and mating connection.
Choose a straight, 45-degree, or 90-degree fitting according to the hose routing.
Make sure the fitting series matches the hose construction, insert, ferrule, and crimping system.
Check the insertion depth, final crimp diameter, appearance, orientation, and sealing condition.
Each hydraulic fitting is checked through a series of inspection and testing procedures to ensure consistent performance, reliable sealing, and long service life in hydraulic systems.
Selected steel bars are prepared according to the fitting model, dimensions, material grade, and production order. Material specifications are checked before machining begins.
CNC machines form the fitting body, hose stem, hexagonal section, internal bore, and other key structures. Critical dimensions are controlled according to approved drawings.
The NPT thread is machined to the required diameter, pitch, taper, and effective thread length. Accurate thread geometry helps ensure proper engagement with the mating port.
The connection end and related sealing surfaces are precisely machined according to the fitting design. Surface shape, angle, and finish are controlled to support reliable assembly and sealing.
Inspectors check the thread, body dimensions, hose stem, bore, effective length, and fitting angle using gauges and measuring instruments. Nonconforming parts are separated before the next process.
Finished fittings are checked for burrs, damaged threads, scratches, coating defects, contamination, and mixed models. Only products meeting the appearance and identification requirements proceed to packing.
Common options include male NPT, female NPT, and female NPSM swivel fittings. Straight, 45-degree, and 90-degree configurations are available depending on the fitting series and size.
Measure the thread diameter, check the threads per inch, confirm whether the thread is tapered, and verify the mating port. The measured diameter should not be used directly as the nominal NPT size.
No. NPT uses a tapered thread and normally seals in the thread area, while NPSM uses a straight thread and usually seals through a matching mechanical seat.
Confirm the hose ID, dash size, hose standard, reinforcement structure, actual outside diameter, fitting series, ferrule, and crimp specification. Thread size alone is not enough.
Carbon steel with zinc-plated finish is commonly supplied. Stainless steel, special materials, alternative surface treatments, and custom marking can be evaluated according to the application and order quantity.
Please provide the hose size and standard, connection type, thread size, fitting angle, fitting series, material, quantity, destination, and available product photos, drawings, or current part numbers.
Topa offers different types of NPT one-piece hydraulic fitting, this catalog includes all kinds of NPT hydraulic fittings. If you need more information on one-piece hydraulic fitting, please contact us.
