Triple-passage G1/8 threaded rotary joint with 4mm orifice for pneumatic and light fluid applications. PTFE composite seal, AL6061 body. ?78.9 × 63.9 mm, 390 g. Ships in 7 days.
BP-3P-0007 is a precision triple-passage G1/8 threaded rotary joint with a 4mm orifice and deep groove ball bearing support. Intended for compact automation and robot EOAT applications where low idle torque and leakage control are important. Each unit is 100% pressure tested before shipment.
| Model Number | BP-3P-0007 |
|---|---|
| Passages | 3-in-3-out (triple passage) |
| Orifice Size | 4 mm |
| Thread Type | G1/8 (BSPP) |
| Rotor Connection | 3-M5 (rotating side) |
| Stator Connection | 3-?6 mm Through-Hole (fixed side) |
| Mount Type | G1/8 Threaded |
| Max Pressure | 1 MPa (10 bar / 145 psi) — derate to 0.7 MPa for continuous water or coolant duty |
| Max Speed | 200 RPM — derate to 150 RPM for continuous water or coolant |
| Compatible Media | Air, Water, Water-Soluble Coolant, Light Hydraulic Oil |
| Leakage acceptance | Specified by model; confirm test criteria before ordering. |
| Body Material | AL6061 Aluminum Alloy |
|---|---|
| Seal Type | PTFE Composite Seal with FKM O-ring backup |
| Bearing Type | Deep Groove Ball Bearing |
| Operating Temperature | -20°C to +80°C |
| Net Weight | Approx. 0.39 kg (390 g) |
| Dimensions | ?78.9 × 63.9 mm |
| Idle Torque | ≤2 N·m |
| Service Life | ≥8,000 hours (rated conditions) |
|---|---|
| Certifications | ISO 9001:2015, CE, RoHS |
| Warranty | 12 Months |
AL6061 aluminum body: 6061-T6 aluminum alloy with yield strength 276 MPa and excellent corrosion resistance when anodized. The 0.39 kg mass and ?78.9 × 63.9 mm envelope make this ideal for robot EOAT and desktop automation where every gram and millimeter matters. Anodizing thickness is 15–25 microns for corrosion protection. Not recommended for abrasive coolant or high-impact environments.
PTFE composite seal: Polytetrafluoroethylene with glass fiber and graphite filler. Self-lubricating, chemically inert, and rated for -200°C to +260°C. The composite maintains low friction (0.05–0.10 against steel) while providing the sealing integrity needed for 100% pressure testing. FKM O-ring provides static sealing at the housing interface.
Deep groove ball bearing: Provides radial and axial support with ≤2 N·m idle torque. The bearing reduces seal side load and extends seal life from 6 months to 12+ months under rated conditions. Inspect bearing annually for play — replace if radial play exceeds 0.05 mm. The bearing is pre-lubricated and sealed for life under normal duty.
BP-3P-0007 is designed for compact, precision applications where G1/8 threads, low idle torque, and a small envelope are required. The 4mm orifice is optimized for small vacuum cups and precision grippers. This model may be suitable for the listed applications when its passage count, mounting, medium, pressure, speed, and temperature limits match the machine requirements.
Proper installation is critical for BP-3P-0007 due to its compact size and precision bearing. The most common cause of early failure is overtightening the G1/8 thread, which cracks the AL6061 housing, or applying side loads that damage the deep groove ball bearing. Follow these steps for reliable operation.
BP-3P-0007 uses G1/8 BSP parallel (BSPP) threads per ISO 228-1. Confirm your equipment has G1/8 female threads or appropriate adapters. The rotor side has 3× M5 mounting holes; the stator side has 3× ?6 mm through-holes. Download the 2D drawing for exact thread dimensions, pitch (0.907 mm for G1/8), and tolerances. NPT and metric thread options are available as custom orders with 10-day lead time.
Use PTFE tape (3–4 wraps) or anaerobic liquid thread sealant on the G1/8 male threads. Hand-tighten plus 1/4 turn maximum. Overtightening cracks the AL6061 threads or distorts the seal housing, compressing the PTFE seal unevenly. Torque spec: 8–12 N·m for G1/8. Use a torque wrench — the 0.39 kg aluminum body is less forgiving than steel. Never use pipe wrenches on this compact joint.
Use the 3× M5 mounting holes on the rotor side to secure the rotary joint body to a fixed bracket. Torque M5 bolts to 3–5 N·m. Never let the body rotate freely with the shaft — the supply hoses will twist and the seal will experience reverse torque, accelerating wear. The anti-rotation bracket must not apply side load to the body — side loads >5 N will damage the deep groove ball bearing and increase idle torque.
Use flexible hoses (not rigid pipe) to connect the stationary side. Rigid pipe transfers vibration and thermal expansion directly to the joint, stressing the seal and bearing. Install a 40-micron filter upstream to protect the PTFE seal from debris. For water or coolant, add a Y-strainer (60 mesh) to prevent particulate damage. The 4mm orifice will restrict flow — verify your application's flow requirement is <50 L/min at 0.6 MPa.
Run at low pressure (0.2 MPa) and low speed (50–100 RPM) for 5 minutes without load. This beds the PTFE seal against the shaft surface and distributes grease in the deep groove ball bearing. Check all three seal interfaces for leaks. Listen for bearing noise — smooth operation indicates proper installation. If dry and quiet, gradually increase to operating pressure and speed over 10 minutes. Skipping the run-in is the #2 cause of early seal and bearing failure.
Full dimensions, tolerances, G1/8 thread specs, 4mm orifice details, 3-M5 rotor mounting pattern, ?6 mm stator through-holes, bearing specs, and seal groove details. 120 KB.
Free 3D files provided after inquiry. Includes exact G1/8 thread geometry, 4mm orifice paths, 3-M5 mounting pattern, and deep groove ball bearing envelope. Use for CAD fit verification before ordering.
Complete guide: thread matching, torque specs, anti-rotation, bearing protection, filtration, run-in procedure, and maintenance checklist. 650 KB.
AL6061 material traceability, hardness test report, bearing specification, and RoHS compliance certificate. Available upon request with order.
Not sure if BP-3P-0007 is the right model? Use this comparison to decide — and know exactly when to upgrade to a larger orifice, flange mount, or higher-pressure joint.
| Your Requirement | BP-3P-0007 Fit | Better Alternative | Why Upgrade |
|---|---|---|---|
| Single air line, handheld tool, weight critical | ❌ Overkill — 0.39 kg, 3 passages | BP-1P-0003 | 0.08 kg aluminum, single passage, lower cost |
| Dual air lines, 1 MPa, general automation | ⚠️ Fewer passages needed | BP-2P-0002 | Same G1/8 thread, 1.5 MPa, dual passage |
| Triple lines, G1/8 thread, compact, 4mm orifice | ✅ Perfect | — | — |
| Triple lines, G1/4 larger thread, 6mm orifice | ❌ Wrong size | BP-3P-0006 | G1/4 thread, 6mm orifice, ?64 × 78 mm for higher flow |
| Triple lines, flange mount preferred | ❌ Wrong mount | BP-3P-0004 | Same 3 passages, flange mount, better vibration resistance |
| Pressure >1.0 MPa (e.g., 1.5 MPa hydraulic) | ❌ Over pressure | BP-2P-130-0001 | 5 MPa rated, flange mount, heavy duty |
| 4+ independent passages needed | ❌ Too few passages | BP-8P-0001 | 8 passages with independent seals, flange mount |
The #1 cause of BP-3P-0007 warranty claims is overtightening. A technician applies 15 N·m on a G1/8 thread rated for 8–12 N·m. The AL6061 threads crack, creating a leak path that cannot be repaired. The compact 0.39 kg body has less material than larger joints, making it less forgiving of over-torque. Rule: Use a torque wrench. Hand-tighten plus 1/4 turn maximum. G1/8: 8–12 N·m. Never use pipe wrenches. If the thread leaks at proper torque, replace the PTFE tape — do not tighten further.
A machine builder tries to run a large vacuum cup (80 mm diameter) through BP-3P-0007's 4mm orifice. The orifice restricts flow to 30 L/min at 0.6 MPa, but the cup needs 60 L/min. The vacuum pump runs continuously, overheating the PTFE seal and causing premature failure. The builder blames the joint — but the root cause is flow mismatch. Rule: Verify your flow requirement is <50 L/min per passage at 0.6 MPa. For higher flow, use BP-3P-0006 (6mm orifice) or BP-3P-0004 (flange mount with larger passages). The $10 savings on a smaller joint costs $45 in seal replacements.
A robot integrator mounts BP-3P-0007 on an EOAT bracket that applies 10 N of side load during acceleration. The deep groove ball bearing is designed for radial loads under 5 N. Within 3 months, the bearing develops play >0.05 mm, increasing idle torque from 2 N·m to 5 N·m. The servo motor overheats and the positioning accuracy degrades. Rule: Mount the joint so the body experiences only axial loads. Use a flexible hose loop to isolate side forces. The anti-rotation bracket must not push or pull the body — it should only prevent rotation.
Other rotary joints commonly purchased with BP-3P-0007 — or the models you upgrade to when your application needs higher flow, flange mount, or more passages.
The standard BP-3P-0007 uses a full AL6061 aluminum body with deep groove ball bearing support for low idle torque and smooth rotation. Pressure and leakage checks are specified by model. Confirm the applicable test pressure, duration, and acceptance criteria with Begapunk before ordering. For full steel construction or special bearing specifications, contact our engineering team. All versions are manufactured under ISO 9001:2015 quality management and carry CE and RoHS certifications. Material certificates with full traceability are available upon request with every order.
Yes — the PTFE composite seal and FKM O-ring are compatible with water, water-soluble coolant, and light hydraulic oil. For continuous water duty, derate pressure to 0.7 MPa and speed to 150 RPM to reduce seal wear. The AL6061 body is anodized for corrosion resistance, making it suitable for intermittent water and coolant exposure. However, the deep groove ball bearing is not sealed against water ingress — for continuous water duty, specify a sealed bearing option or use BP-3P-0004 (flange mount) with external bearing protection. Always use a 40-micron filter for water duty.
BP-3P-0007 uses G1/8 BSP parallel (BSPP) threads per ISO 228-1 with 0.907 mm pitch. BSP parallel threads seal on a gasket or O-ring at the port face, not on the thread itself. This means PTFE tape on the thread is for sealing only; the mechanical connection is made by the flat face compressing against the mating port. Download the 2D PDF drawing for exact thread dimensions, pitch, and tolerances. NPT and metric thread options are available as custom orders with 10-day lead time. The rotor side uses 3-M5 mounting holes and the stator side uses 3-?6 mm through-holes.
Yes — free 3D STEP and IGES files are provided after you send an inquiry. The file includes exact G1/8 thread geometry, 4mm orifice paths, 3-M5 rotor mounting pattern, ?6 mm stator through-holes, deep groove ball bearing envelope, and the 0.39 kg AL6061 body. Use the 3D file to verify clearance, port direction, thread engagement length, and bearing access in your CAD assembly before ordering. 3D files may be provided for qualified projects after the application requirements are reviewed. File availability and response time depend on the model and the project information provided. Custom configurations are modeled on request.
Upgrade when your application exceeds the 1 MPa pressure limit, 200 RPM speed limit, 4mm orifice flow capacity, or needs a different mounting style. Common triggers: (1) Your pressure requirement rises above 1.0 MPa — BP-2P-130-0001 handles 5 MPa with flange mount. (2) You need higher flow than the 4mm orifice allows — BP-3P-0006 offers 6mm orifice with G1/4 thread. (3) You need flange mount for better vibration resistance — BP-3P-0004 provides the same 3 passages with flange mounting. (4) You need 4 or more channels — BP-8P-0001 provides 8 passages. The upgrade cost is typically $15–$90 more, but it prevents seal failure from over-pressure or flow starvation.
We design custom rotary joints for any number of passages, pressure, thread type, and mounting style. Free 3D STEP file with every inquiry. Typical custom lead time: 10–14 days.
Request Custom Design →Technical Note: All pressure ratings, speed ratings, and material specifications referenced on this page are based on Begapunk BP-series standard pneumatic rotary joints tested under controlled laboratory conditions. Actual performance depends on operating conditions, media quality, installation practices, and maintenance schedule. For applications outside standard ratings — including high-pressure hydraulic above 1 MPa, continuous water immersion, food-grade, or cleanroom environments — consult Begapunk factory engineering before specification. Last updated: June 11, 2026.